![[Valid RSS]](images/valid-rss-rogers.png "Valid RSS")
This is a valid RSS feed.
This feed is valid, but interoperability with the widest range of feed readers could be improved by implementing the following recommendations.
line 86, column 0: (18 occurrences) [help]
<script type="text/javascript">
line 89, column 8: (8 occurrences) [help]
<br/>]]></description>
^
</channel>
^
<?xml version="1.0" encoding="UTF-8"?><rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/"> <channel> <title>Glass nozzles for extruders</title> <description>I have been playing with the glass work. I have one basic nozzle that could be put on an extruder right now, but I want to play with some improvements. First, some pictures. [img]http://objects.reprap.org/mediawiki/images/a/ab/Glass_nozzle_tip_orifice_2.png[/img]This is the tip of the glass nozzle, after using a stained glass diamond grinder to remove enough of the ‘blob’ at the tip to break into the funnel that forms when the tubing get hot and the surface tension pulls it together. This makes it easy to get almost any size opening you want, you just need a wire or probe that will just fit the opening you want, and continue grinding until it fits. [img]http://objects.reprap.org/mediawiki/images/7/7b/Glass_nozzle_tip_side_view.png[/img]This is a side view of the tip. You can just see the funnel inside the glass pointing down towards the opening. Other people have posted that the greats resistance to plastic flowing out of the extruder is not the PTFE or the brass 3mm sections, but where it narrows done to 0.5mm. This automatically makes a very smooth, gentle transition from full width to reaching the narrowest section right at the end, so this should greatly reduce internal pressure and torque needed by the stepper motor. I am looking forward to putting one together to see. [img]http://objects.reprap.org/mediawiki/images/8/84/Glass_nozzle_1_side_view.png[/img]Here is the full length of the first practice piece. All three images (with annoying captions) we made using my new, USB microscope camera. It is cheap, and has an INCREDIBLY narrow depth of field, so this photo was hard to keep from being blurring somewhere. [img]http://objects.reprap.org/mediawiki/images/d/dc/IMG_7584.JPG[/img]Here is a full length shot with a tape measure for scale.You can see that this piece is about 2 inches long, or a little over 5 cm. [img]http://objects.reprap.org/mediawiki/images/e/ea/010810140016-01.jpg[/img]So far, I have scrounged most of the tools from other jobs. When I found that a propane torch could not soften the boro-silicate, I first clamped an old, used oxy-acetylene torch to the table, and worked the glass in the flame by hand. I tried a hammer to roll it against the steel table, but that did not work as well at making the funnel as just holding it vertically and heating the bottom. I also tried a screwdriver the shape it, but also got nowhere. [img]http://objects.reprap.org/mediawiki/images/d/da/010810140200-01.jpg[/img]Someone suggested using MAPP gas. I don’t think MAPP gas alone will melt the boro-silicate, but probably would work on standard window pane glass, or ‘soft’ glass. If you want to make your own glass nozzles, and don’t plan on making too many, this is an inexpensive way to get going. In the US, Home Depot sells a complete MAPP plus Oxygen torch package for $60. But it will only run for 20-30 minutes before you run out of something and have more cans of gas. A new can of Oxygen is $9 for 1.5 cubic feet, whereas to refill the welding tank, I think it was $35 for 40 cubuc feet. Obviously, the cheap start becomes expensive after awhile. I plan on practicing some more, and have several improvements I want to try to accomplish. First is that the other end of the nozzle needs something to keep it from sliding out of the clamp when the filament is pushed into it. I plan on heating the other end and widening it into a flange, just like the plunger end of a hypodermic syringe. Next, I am trying to find a way to heat the tubing and embed the nichrome wire directly into it. This has not gone well so far. If the wire gets into the flame, it just burns up and disappears. If I try to get the glass hot and then push the wire into it, I quickly find I need 3 or 4 more hands! At the very least, I want to make some thermocouples and embed them in the glass so that the temperature reading will be more accurate. I may have to live with applying the nichrome wire with Kapton tape, just like on the brass nozzles. Mike</description> <link>https://reprap.org/forum/read.php?1,53676,53676#msg-53676</link> <lastBuildDate>Sat, 11 May 2024 00:57:29 -0400</lastBuildDate> <generator>Phorum 5.2.23</generator> <item> <guid>https://reprap.org/forum/read.php?1,53676,189364#msg-189364</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,189364#msg-189364</link> <description><![CDATA[ I observed you attempt to put the heater inside a capillary tube of glass. Looks interesting. How about simply making a section of your extruder out of the spiral rather than wrapping it around another glass. I think the guys that made the tips for the experimental glass tips would have the skill to do this quite well. I would expect that they could construct an extruder that was heated wrapped so that the wires came out in a convenient location and so that the heating was right at the tip. This is properly the job for a skilled glass operation. It would be 3 segments. 1 the upper segment is just glass tube with a proper entrance. The second segment is the heater spiral. The third segment is the tip that extrudes. I would think this could be made pretty strong and pretty good. If the top segment were made with a proper taper in it the risk of leaks into a PEEK mount is just about zero. I think you guys are onto something here. <br /><br />I also suggest you look at ultrasonic heating because it can be applied right at the site of need and help fuse to the work piece allowing plastic extrusion in a true 6 axis application. --- This has real possibilities!]]></description> <dc:creator>Paul Noel</dc:creator> <category>General</category> <pubDate>Sun, 03 Mar 2013 21:53:21 -0500</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,70900#msg-70900</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,70900#msg-70900</link> <description><![CDATA[ ok rocketscientist: it took me a while, but I finally have one of the glass nozzles you sent me attached to an extruder.<br />I have a thin ptfe sleeving tube (thanks to Have Blue who kindly ordered it from mcmaster carr and posted it to Australia) whose OD almost perfectly matches the ID of the glass. This tube is pushed in all the way to the melt zone. It was too tight to push in until I lightly sanded it which prevented it from suctioning on to the glass. This tube both makes PLA easier to push through if it goes glassy and also takes up a bit of the slop (the ID was a bit big for 3mm filament). I now print with a fan blowing on the workpiece, so any heat that may have been convecting up the tube inside my carriage is now whisked away. I was able to make a successful print:<br /><div id="div_acd35fc1301f01f2645c4092210ae7a0" class="mod_embed_images" style="width:140px"> <div id="imagediv_acd35fc1301f01f2645c4092210ae7a0" class="mod_embed_images_image" style="width:140px; height:120px"> <a href="http://i53.tinypic.com/2vcib0n.jpg"> <img src="/forum/thumbcache/0aa/be2/76d/4ea/643/01a/382/ab3/967/2f7/29_800x400.gif" width="140" height="120" id="image_acd35fc1301f01f2645c4092210ae7a0" alt="2vcib0n.jpg" title="2vcib0n.jpg"/> </a> </div> <div class="mod_embed_images_info " id="info_acd35fc1301f01f2645c4092210ae7a0" > <a id="link_acd35fc1301f01f2645c4092210ae7a0" href="http://i53.tinypic.com/2vcib0n.jpg">2vcib0n.jpg</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('acd35fc1301f01f2645c4092210ae7a0', '/forum/thumbcache/0aa/be2/76d/4ea/643/01a/382/ab3/967/2f7/29_800x400.gif', 'http://i53.tinypic.com/2vcib0n.jpg', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Fi53.tinypic.com%2F2vcib0n.jpg', '', 70900, 800, 400, 'Loading image ...', false);</script><br/>]]></description> <dc:creator>Greg Frost</dc:creator> <category>General</category> <pubDate>Tue, 18 Jan 2011 08:08:54 -0500</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,67156#msg-67156</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,67156#msg-67156</link> <description><![CDATA[ Buback,<br /> I have attempted to make to make the type of glass nozzles you requested. Some have a lip slightly up from the end so that two plates can sandwich the lip between them. Others have a flange at the end that I worked harder on getting perfectly flat and perpendicular. I also chucked several of them in the lathe and tried to square up the rounded edges and and make the addition more circular. As the photo bellow illustrates, this is not easy. If one of these designs should prove useful, I will have to work on improving the manufacture of that shape.<br /><br />Greg,<br /> I have no idea how the heat is getting up the glass. When I work the glass, the hot end is just at the edge of a dull red glow, and the other end I am usually holding in my hand. I can only guess that with time, the heat slowly makes its way up. That still means that very little heat energy is getting to the cold end, and it would not take much of a radiator to cool it. Perhaps try a brass grommet that will slide over the glass tube and crimp it just enough to be a tight fit. Or use the high temperature adhesive that I think Makershed sells.<br /><br /><div id="div_21047d88b024344cbeb590973e4bc10a" class="mod_embed_images_extended" style="width:533px"> <div id="imagediv_21047d88b024344cbeb590973e4bc10a" class="mod_embed_images_image" style="width:533px; height:400px"> <a href="http://www.reprap.org/mediawiki/images/0/0e/Replacable_tip_glass_nozzles.JPG"> <img src="/forum/thumbcache/dc9/9c4/cc0/ee5/3c2/b52/d9b/943/169/699/af_800x400.png" width="533" height="400" id="image_21047d88b024344cbeb590973e4bc10a" alt="Replacable_tip_glass_nozzles.JPG" title="Replacable_tip_glass_nozzles.JPG"/> </a> </div> <div class="mod_embed_images_info " id="info_21047d88b024344cbeb590973e4bc10a" style="display:block"> <a id="link_21047d88b024344cbeb590973e4bc10a" href="http://www.reprap.org/mediawiki/images/0/0e/Replacable_tip_glass_nozzles.JPG">Replacable_tip_glass_nozzles.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('21047d88b024344cbeb590973e4bc10a', '/forum/thumbcache/dc9/9c4/cc0/ee5/3c2/b52/d9b/943/169/699/af_800x400.png', 'http://www.reprap.org/mediawiki/images/0/0e/Replacable_tip_glass_nozzles.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Fwww.reprap.org%2Fmediawiki%2Fimages%2F0%2F0e%2FReplacable_tip_glass_nozzles.JPG', '', 67156, 800, 400, 'Loading image ...', false);</script><br/>]]></description> <dc:creator>rocket_scientist</dc:creator> <category>General</category> <pubDate>Sun, 28 Nov 2010 22:28:42 -0500</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,66723#msg-66723</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,66723#msg-66723</link> <description><![CDATA[ I adapted a wades extruder for mounting the glass nozzle to and attempted to print something, but it was pretty much a disaster. The heat traveled all the way up the glass nozzle and softened the carriage (which I only had fastened in one place anyway), this caused the (PLA) extruder to buckle and the print became quite inaccurate. I also noticed that whenever the extruder stopped for a while, it had trouble starting up again. I think this is because as the heat traveled up the glass is further while it was stopped, it softened more of the filament. Because the filament is not a snug fit, it expands when the extruder starts again rather than pushing more out the extrusion tip.<br /><br />Having seen this, I think the top of the glass will need some form of cooling (aluminium housing and fins and a fan?)<br /><br />Has anyone in the US been able to order the PTFE sleeving from McMaster discussed earlier in this thread that will go around the filament and inside the glass tube? That would help with the expansion of the filament and would also make it slide out easier. McMaster don't ship outside the US, so if someone can get some, I'd like to try it.<br /><br /><div id="div_a51d8fa9c348c8d8ddf5fe5d3ca5c914" class="mod_embed_images" style="width:400px"> <div id="imagediv_a51d8fa9c348c8d8ddf5fe5d3ca5c914" class="mod_embed_images_image" style="width:400px; height:300px"> <a href="http://reprap.org/mediawiki/images/thumb/6/6c/Glass_Extruder.JPG/400px-Glass_Extruder.JPG"> <img src="/forum/thumbcache/275/883/db2/03b/c84/1e5/6dc/c5d/461/77e/d3_800x400.jpg" width="400" height="300" id="image_a51d8fa9c348c8d8ddf5fe5d3ca5c914" alt="400px-Glass_Extruder.JPG" title="400px-Glass_Extruder.JPG"/> </a> </div> <div class="mod_embed_images_info " id="info_a51d8fa9c348c8d8ddf5fe5d3ca5c914" > <a id="link_a51d8fa9c348c8d8ddf5fe5d3ca5c914" href="http://reprap.org/mediawiki/images/thumb/6/6c/Glass_Extruder.JPG/400px-Glass_Extruder.JPG">400px-Glass_Extruder.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('a51d8fa9c348c8d8ddf5fe5d3ca5c914', '/forum/thumbcache/275/883/db2/03b/c84/1e5/6dc/c5d/461/77e/d3_800x400.jpg', 'http://reprap.org/mediawiki/images/thumb/6/6c/Glass_Extruder.JPG/400px-Glass_Extruder.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Freprap.org%2Fmediawiki%2Fimages%2Fthumb%2F6%2F6c%2FGlass_Extruder.JPG%2F400px-Glass_Extruder.JPG', '', 66723, 800, 400, 'Loading image ...', false);</script><div id="div_cfd9e341cf79644bc8d61cc9a1a63924" class="mod_embed_images" style="width:400px"> <div id="imagediv_cfd9e341cf79644bc8d61cc9a1a63924" class="mod_embed_images_image" style="width:400px; height:300px"> <a href="http://reprap.org/mediawiki/images/thumb/c/cf/Glass_Extruder2.JPG/400px-Glass_Extruder2.JPG"> <img src="/forum/thumbcache/193/f12/f6c/7ff/2bf/a57/423/a34/d68/b71/ed_800x400.jpg" width="400" height="300" id="image_cfd9e341cf79644bc8d61cc9a1a63924" alt="400px-Glass_Extruder2.JPG" title="400px-Glass_Extruder2.JPG"/> </a> </div> <div class="mod_embed_images_info " id="info_cfd9e341cf79644bc8d61cc9a1a63924" > <a id="link_cfd9e341cf79644bc8d61cc9a1a63924" href="http://reprap.org/mediawiki/images/thumb/c/cf/Glass_Extruder2.JPG/400px-Glass_Extruder2.JPG">400px-Glass_Extruder2.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('cfd9e341cf79644bc8d61cc9a1a63924', '/forum/thumbcache/193/f12/f6c/7ff/2bf/a57/423/a34/d68/b71/ed_800x400.jpg', 'http://reprap.org/mediawiki/images/thumb/c/cf/Glass_Extruder2.JPG/400px-Glass_Extruder2.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Freprap.org%2Fmediawiki%2Fimages%2Fthumb%2Fc%2Fcf%2FGlass_Extruder2.JPG%2F400px-Glass_Extruder2.JPG', '', 66723, 800, 400, 'Loading image ...', false);</script><div id="div_65398b7e82628d2b8e1a79b2ec51646b" class="mod_embed_images" style="width:400px"> <div id="imagediv_65398b7e82628d2b8e1a79b2ec51646b" class="mod_embed_images_image" style="width:400px; height:300px"> <a href="http://reprap.org/mediawiki/images/thumb/f/f2/Glass_Extruder_Printing.JPG/400px-Glass_Extruder_Printing.JPG"> <img src="/forum/thumbcache/63b/c96/058/939/1c5/239/c19/75f/089/1e8/29_800x400.jpg" width="400" height="300" id="image_65398b7e82628d2b8e1a79b2ec51646b" alt="400px-Glass_Extruder_Printing.JPG" title="400px-Glass_Extruder_Printing.JPG"/> </a> </div> <div class="mod_embed_images_info " id="info_65398b7e82628d2b8e1a79b2ec51646b" > <a id="link_65398b7e82628d2b8e1a79b2ec51646b" href="http://reprap.org/mediawiki/images/thumb/f/f2/Glass_Extruder_Printing.JPG/400px-Glass_Extruder_Printing.JPG">400px-Glass_Extruder_Printing.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('65398b7e82628d2b8e1a79b2ec51646b', '/forum/thumbcache/63b/c96/058/939/1c5/239/c19/75f/089/1e8/29_800x400.jpg', 'http://reprap.org/mediawiki/images/thumb/f/f2/Glass_Extruder_Printing.JPG/400px-Glass_Extruder_Printing.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Freprap.org%2Fmediawiki%2Fimages%2Fthumb%2Ff%2Ff2%2FGlass_Extruder_Printing.JPG%2F400px-Glass_Extruder_Printing.JPG', '', 66723, 800, 400, 'Loading image ...', false);</script><div id="div_c72346679a3be00108d37ca605c6ae4b" class="mod_embed_images" style="width:400px"> <div id="imagediv_c72346679a3be00108d37ca605c6ae4b" class="mod_embed_images_image" style="width:400px; height:300px"> <a href="http://reprap.org/mediawiki/images/thumb/3/3b/Glass_Print1.JPG/400px-Glass_Print1.JPG"> <img src="/forum/thumbcache/73f/4d7/a3f/564/0a1/c8d/23d/239/8da/4ac/ee_800x400.jpg" width="400" height="300" id="image_c72346679a3be00108d37ca605c6ae4b" alt="400px-Glass_Print1.JPG" title="400px-Glass_Print1.JPG"/> </a> </div> <div class="mod_embed_images_info " id="info_c72346679a3be00108d37ca605c6ae4b" > <a id="link_c72346679a3be00108d37ca605c6ae4b" href="http://reprap.org/mediawiki/images/thumb/3/3b/Glass_Print1.JPG/400px-Glass_Print1.JPG">400px-Glass_Print1.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('c72346679a3be00108d37ca605c6ae4b', '/forum/thumbcache/73f/4d7/a3f/564/0a1/c8d/23d/239/8da/4ac/ee_800x400.jpg', 'http://reprap.org/mediawiki/images/thumb/3/3b/Glass_Print1.JPG/400px-Glass_Print1.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Freprap.org%2Fmediawiki%2Fimages%2Fthumb%2F3%2F3b%2FGlass_Print1.JPG%2F400px-Glass_Print1.JPG', '', 66723, 800, 400, 'Loading image ...', false);</script><div id="div_25937b2a9f279c23fc2744576ab10ca6" class="mod_embed_images" style="width:400px"> <div id="imagediv_25937b2a9f279c23fc2744576ab10ca6" class="mod_embed_images_image" style="width:400px; height:300px"> <a href="http://reprap.org/mediawiki/images/thumb/d/d8/Glass_Print2.JPG/400px-Glass_Print2.JPG"> <img src="/forum/thumbcache/aa5/e7e/894/cab/d2e/bd6/4c4/5f2/d86/4c8/31_800x400.jpg" width="400" height="300" id="image_25937b2a9f279c23fc2744576ab10ca6" alt="400px-Glass_Print2.JPG" title="400px-Glass_Print2.JPG"/> </a> </div> <div class="mod_embed_images_info " id="info_25937b2a9f279c23fc2744576ab10ca6" > <a id="link_25937b2a9f279c23fc2744576ab10ca6" href="http://reprap.org/mediawiki/images/thumb/d/d8/Glass_Print2.JPG/400px-Glass_Print2.JPG">400px-Glass_Print2.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('25937b2a9f279c23fc2744576ab10ca6', '/forum/thumbcache/aa5/e7e/894/cab/d2e/bd6/4c4/5f2/d86/4c8/31_800x400.jpg', 'http://reprap.org/mediawiki/images/thumb/d/d8/Glass_Print2.JPG/400px-Glass_Print2.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Freprap.org%2Fmediawiki%2Fimages%2Fthumb%2Fd%2Fd8%2FGlass_Print2.JPG%2F400px-Glass_Print2.JPG', '', 66723, 800, 400, 'Loading image ...', false);</script><div id="div_392776196cf0be1c0fd09886b6886688" class="mod_embed_images" style="width:400px"> <div id="imagediv_392776196cf0be1c0fd09886b6886688" class="mod_embed_images_image" style="width:400px; height:300px"> <a href="http://reprap.org/mediawiki/images/thumb/e/e5/Glass_Print3.JPG/400px-Glass_Print3.JPG"> <img src="/forum/thumbcache/634/c27/665/ef3/888/28d/6fe/e5c/cd9/d97/aa_800x400.jpg" width="400" height="300" id="image_392776196cf0be1c0fd09886b6886688" alt="400px-Glass_Print3.JPG" title="400px-Glass_Print3.JPG"/> </a> </div> <div class="mod_embed_images_info " id="info_392776196cf0be1c0fd09886b6886688" > <a id="link_392776196cf0be1c0fd09886b6886688" href="http://reprap.org/mediawiki/images/thumb/e/e5/Glass_Print3.JPG/400px-Glass_Print3.JPG">400px-Glass_Print3.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('392776196cf0be1c0fd09886b6886688', '/forum/thumbcache/634/c27/665/ef3/888/28d/6fe/e5c/cd9/d97/aa_800x400.jpg', 'http://reprap.org/mediawiki/images/thumb/e/e5/Glass_Print3.JPG/400px-Glass_Print3.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Freprap.org%2Fmediawiki%2Fimages%2Fthumb%2Fe%2Fe5%2FGlass_Print3.JPG%2F400px-Glass_Print3.JPG', '', 66723, 800, 400, 'Loading image ...', false);</script><br/>]]></description> <dc:creator>Greg Frost</dc:creator> <category>General</category> <pubDate>Sat, 20 Nov 2010 22:05:58 -0500</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65802#msg-65802</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65802#msg-65802</link> <description><![CDATA[ moon rabbit,<br /> it looks like someone will need to acquire a few and see if the inside diameter is large enough for the 3 mm plastic filament to pass, or perhaps shift to the 1.8mm filaments. My sister works for a microscope stain and medical lab reagents house, and they might have some use once pipettes that she can pull for me to test after they have finished with them.<br /><br /><br />Mike]]></description> <dc:creator>rocket_scientist</dc:creator> <category>General</category> <pubDate>Tue, 09 Nov 2010 13:16:09 -0500</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65800#msg-65800</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65800#msg-65800</link> <description><![CDATA[ Here's a useful wikipedia article on glass to metal seals. it's very informative.<br /><br /><a href="http://en.wikipedia.org/wiki/Glass-to-metal_seal" target="_blank" rel="nofollow">Glass-to-metal seals</a>]]></description> <dc:creator>Buback</dc:creator> <category>General</category> <pubDate>Tue, 09 Nov 2010 12:54:44 -0500</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65740#msg-65740</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65740#msg-65740</link> <description><![CDATA[ I just happened onto this site, looking for info on embedding nichrome in borosilicate, and your pictures of the nozzles you made look a lot like the tips of the volumetric pipets I use at work. An 0.1 ml volumetric pipet from Corning or Kinble will have a very tiny, perfectly round hole in the tip. You'd just need to cut it off. You can often find these on eBay or at surplus sales. Some have tempered tips for extra strength.<br /><br />Example: [<a href="http://compare.ebay.com/like/250471970614?ltyp=AllFixedPriceItemTypes&_dmd=Gallery&var=sbar&rvr_id=165383165328&crlp=1_263602_304692&UA=WVF%3F&GUID=5053578212a0a0e205408790ff2d1fbb&itemid=250471970614&ff4=263602_304692" target="_blank" rel="nofollow">compare.ebay.com</a>]]]></description> <dc:creator>moon_rabbit</dc:creator> <category>General</category> <pubDate>Mon, 08 Nov 2010 22:55:35 -0500</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65320#msg-65320</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65320#msg-65320</link> <description><![CDATA[ yes i forgot to mention that the flanged nozzle is my preferred choice. it should be the strongest and simplest of the metal nozzle designs.<br /><br />I also want to post about the cold end attachment i'm using. <br />Wade's has a 16mm diameter by 10 mm tall cavity in the bottom, where the filament exits the extruder. I filled this cavity with leftover M8 washers. (I don't know if they are standardized at 16mm OD, but mine were)<br /><div id="div_8fe48720fcdd8bc9123f15c2e95b35ec" class="mod_embed_images" > <div id="imagediv_8fe48720fcdd8bc9123f15c2e95b35ec" class="mod_embed_images_image" > <noscript> <div> <a href="http://lh5.ggpht.com/_Rq679ttrduQ/TNDhLxv5nYI/AAAAAAAAEK0/eH6l_C-jPKc/s400/DSC04946.JPG"> <img src="https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTNDhLxv5nYI%2FAAAAAAAAEK0%2FeH6l_C-jPKc%2Fs400%2FDSC04946.JPG" id="image_8fe48720fcdd8bc9123f15c2e95b35ec" alt="DSC04946.JPG" title="DSC04946.JPG"/> </a> </div> </noscript> </div> <div class="mod_embed_images_info " id="info_8fe48720fcdd8bc9123f15c2e95b35ec" > <a id="link_8fe48720fcdd8bc9123f15c2e95b35ec" href="http://lh5.ggpht.com/_Rq679ttrduQ/TNDhLxv5nYI/AAAAAAAAEK0/eH6l_C-jPKc/s400/DSC04946.JPG">DSC04946.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('8fe48720fcdd8bc9123f15c2e95b35ec', 'https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTNDhLxv5nYI%2FAAAAAAAAEK0%2FeH6l_C-jPKc%2Fs400%2FDSC04946.JPG', 'http://lh5.ggpht.com/_Rq679ttrduQ/TNDhLxv5nYI/AAAAAAAAEK0/eH6l_C-jPKc/s400/DSC04946.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTNDhLxv5nYI%2FAAAAAAAAEK0%2FeH6l_C-jPKc%2Fs400%2FDSC04946.JPG', '', 65320, 800, 400, 'Loading image ...', false);</script><br /><br />The glass tube is 8mm and fits perfectly in the washers, centered on the filament exit.<br /><div id="div_54711096b120c2a92bb127addb4bb817" class="mod_embed_images" > <div id="imagediv_54711096b120c2a92bb127addb4bb817" class="mod_embed_images_image" > <noscript> <div> <a href="http://lh6.ggpht.com/_Rq679ttrduQ/TNDhLlwDgZI/AAAAAAAAEKw/YgTSZ3G8W4A/s400/DSC04945.JPG"> <img src="https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh6.ggpht.com%2F_Rq679ttrduQ%2FTNDhLlwDgZI%2FAAAAAAAAEKw%2FYgTSZ3G8W4A%2Fs400%2FDSC04945.JPG" id="image_54711096b120c2a92bb127addb4bb817" alt="DSC04945.JPG" title="DSC04945.JPG"/> </a> </div> </noscript> </div> <div class="mod_embed_images_info " id="info_54711096b120c2a92bb127addb4bb817" > <a id="link_54711096b120c2a92bb127addb4bb817" href="http://lh6.ggpht.com/_Rq679ttrduQ/TNDhLlwDgZI/AAAAAAAAEKw/YgTSZ3G8W4A/s400/DSC04945.JPG">DSC04945.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('54711096b120c2a92bb127addb4bb817', 'https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh6.ggpht.com%2F_Rq679ttrduQ%2FTNDhLlwDgZI%2FAAAAAAAAEKw%2FYgTSZ3G8W4A%2Fs400%2FDSC04945.JPG', 'http://lh6.ggpht.com/_Rq679ttrduQ/TNDhLlwDgZI/AAAAAAAAEKw/YgTSZ3G8W4A/s400/DSC04945.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Flh6.ggpht.com%2F_Rq679ttrduQ%2FTNDhLlwDgZI%2FAAAAAAAAEKw%2FYgTSZ3G8W4A%2Fs400%2FDSC04945.JPG', '', 65320, 800, 400, 'Loading image ...', false);</script><br /><br />I cut a strip of aluminum to fit on the bottom of the wade's, and drilled holes to match the screw holes. I drilled a 8mm hole to match the, now 8mm, cavity. I did this by using a piece of masking tape as a template; stick the tape to the bottom of the extruder, poke a pen through the tape where the mounting screws go the mark the edges of the cavity, unstick, and match the mounting holes to the holes in the aluminum. I then used a large countersink bit i happen to have to make the M8 hole conical.<br /><div id="div_ab1d0688950b50322129896d3af57b0a" class="mod_embed_images" > <div id="imagediv_ab1d0688950b50322129896d3af57b0a" class="mod_embed_images_image" > <noscript> <div> <a href="http://lh3.ggpht.com/_Rq679ttrduQ/TNDhMIqO5xI/AAAAAAAAEK4/Vfbf3tif6Us/s400/DSC04947.JPG"> <img src="https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh3.ggpht.com%2F_Rq679ttrduQ%2FTNDhMIqO5xI%2FAAAAAAAAEK4%2FVfbf3tif6Us%2Fs400%2FDSC04947.JPG" id="image_ab1d0688950b50322129896d3af57b0a" alt="DSC04947.JPG" title="DSC04947.JPG"/> </a> </div> </noscript> </div> <div class="mod_embed_images_info " id="info_ab1d0688950b50322129896d3af57b0a" > <a id="link_ab1d0688950b50322129896d3af57b0a" href="http://lh3.ggpht.com/_Rq679ttrduQ/TNDhMIqO5xI/AAAAAAAAEK4/Vfbf3tif6Us/s400/DSC04947.JPG">DSC04947.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('ab1d0688950b50322129896d3af57b0a', 'https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh3.ggpht.com%2F_Rq679ttrduQ%2FTNDhMIqO5xI%2FAAAAAAAAEK4%2FVfbf3tif6Us%2Fs400%2FDSC04947.JPG', 'http://lh3.ggpht.com/_Rq679ttrduQ/TNDhMIqO5xI/AAAAAAAAEK4/Vfbf3tif6Us/s400/DSC04947.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Flh3.ggpht.com%2F_Rq679ttrduQ%2FTNDhMIqO5xI%2FAAAAAAAAEK4%2FVfbf3tif6Us%2Fs400%2FDSC04947.JPG', '', 65320, 800, 400, 'Loading image ...', false);</script><br /><br />I made another ring to use as a ferrule on this end.<br /><div id="div_52e9d86610f17cffa0a0a7510ce4ab59" class="mod_embed_images" > <div id="imagediv_52e9d86610f17cffa0a0a7510ce4ab59" class="mod_embed_images_image" > <noscript> <div> <a href="http://lh3.ggpht.com/_Rq679ttrduQ/TNDhMpG4DeI/AAAAAAAAEK8/m8FgLBdgezI/s400/DSC04948.JPG"> <img src="https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh3.ggpht.com%2F_Rq679ttrduQ%2FTNDhMpG4DeI%2FAAAAAAAAEK8%2Fm8FgLBdgezI%2Fs400%2FDSC04948.JPG" id="image_52e9d86610f17cffa0a0a7510ce4ab59" alt="DSC04948.JPG" title="DSC04948.JPG"/> </a> </div> </noscript> </div> <div class="mod_embed_images_info " id="info_52e9d86610f17cffa0a0a7510ce4ab59" > <a id="link_52e9d86610f17cffa0a0a7510ce4ab59" href="http://lh3.ggpht.com/_Rq679ttrduQ/TNDhMpG4DeI/AAAAAAAAEK8/m8FgLBdgezI/s400/DSC04948.JPG">DSC04948.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('52e9d86610f17cffa0a0a7510ce4ab59', 'https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh3.ggpht.com%2F_Rq679ttrduQ%2FTNDhMpG4DeI%2FAAAAAAAAEK8%2Fm8FgLBdgezI%2Fs400%2FDSC04948.JPG', 'http://lh3.ggpht.com/_Rq679ttrduQ/TNDhMpG4DeI/AAAAAAAAEK8/m8FgLBdgezI/s400/DSC04948.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Flh3.ggpht.com%2F_Rq679ttrduQ%2FTNDhMpG4DeI%2FAAAAAAAAEK8%2Fm8FgLBdgezI%2Fs400%2FDSC04948.JPG', '', 65320, 800, 400, 'Loading image ...', false);</script><br /><br />it's secure and looks great. it only adds 3mm to the height of the wade's<br /><div id="div_be915608c67259265be24c92efe6b6f2" class="mod_embed_images" > <div id="imagediv_be915608c67259265be24c92efe6b6f2" class="mod_embed_images_image" > <noscript> <div> <a href="http://lh5.ggpht.com/_Rq679ttrduQ/TNDhMhUKxuI/AAAAAAAAELA/GCQsPZZsT0E/s400/DSC04949.JPG"> <img src="https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTNDhMhUKxuI%2FAAAAAAAAELA%2FGCQsPZZsT0E%2Fs400%2FDSC04949.JPG" id="image_be915608c67259265be24c92efe6b6f2" alt="DSC04949.JPG" title="DSC04949.JPG"/> </a> </div> </noscript> </div> <div class="mod_embed_images_info " id="info_be915608c67259265be24c92efe6b6f2" > <a id="link_be915608c67259265be24c92efe6b6f2" href="http://lh5.ggpht.com/_Rq679ttrduQ/TNDhMhUKxuI/AAAAAAAAELA/GCQsPZZsT0E/s400/DSC04949.JPG">DSC04949.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('be915608c67259265be24c92efe6b6f2', 'https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTNDhMhUKxuI%2FAAAAAAAAELA%2FGCQsPZZsT0E%2Fs400%2FDSC04949.JPG', 'http://lh5.ggpht.com/_Rq679ttrduQ/TNDhMhUKxuI/AAAAAAAAELA/GCQsPZZsT0E/s400/DSC04949.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTNDhMhUKxuI%2FAAAAAAAAELA%2FGCQsPZZsT0E%2Fs400%2FDSC04949.JPG', '', 65320, 800, 400, 'Loading image ...', false);</script>.<br /><div id="div_5026683b7436b7c527ea34aaebbc4528" class="mod_embed_images" > <div id="imagediv_5026683b7436b7c527ea34aaebbc4528" class="mod_embed_images_image" > <noscript> <div> <a href="http://lh6.ggpht.com/_Rq679ttrduQ/TNDhLcVQ_bI/AAAAAAAAEKs/HQW7xYh1sB8/s400/DSC04935.JPG"> <img src="https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh6.ggpht.com%2F_Rq679ttrduQ%2FTNDhLcVQ_bI%2FAAAAAAAAEKs%2FHQW7xYh1sB8%2Fs400%2FDSC04935.JPG" id="image_5026683b7436b7c527ea34aaebbc4528" alt="DSC04935.JPG" title="DSC04935.JPG"/> </a> </div> </noscript> </div> <div class="mod_embed_images_info " id="info_5026683b7436b7c527ea34aaebbc4528" > <a id="link_5026683b7436b7c527ea34aaebbc4528" href="http://lh6.ggpht.com/_Rq679ttrduQ/TNDhLcVQ_bI/AAAAAAAAEKs/HQW7xYh1sB8/s400/DSC04935.JPG">DSC04935.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('5026683b7436b7c527ea34aaebbc4528', 'https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh6.ggpht.com%2F_Rq679ttrduQ%2FTNDhLcVQ_bI%2FAAAAAAAAEKs%2FHQW7xYh1sB8%2Fs400%2FDSC04935.JPG', 'http://lh6.ggpht.com/_Rq679ttrduQ/TNDhLcVQ_bI/AAAAAAAAEKs/HQW7xYh1sB8/s400/DSC04935.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Flh6.ggpht.com%2F_Rq679ttrduQ%2FTNDhLcVQ_bI%2FAAAAAAAAEKs%2FHQW7xYh1sB8%2Fs400%2FDSC04935.JPG', '', 65320, 800, 400, 'Loading image ...', false);</script><br /><br />tightening it too much makes it bow a bit too much, could probably do with one less M8 washer. both the plastic and aluminum bow. <br /><div id="div_b79b78aac1a6ac8aa2bc5dd046298aa2" class="mod_embed_images" > <div id="imagediv_b79b78aac1a6ac8aa2bc5dd046298aa2" class="mod_embed_images_image" > <noscript> <div> <a href="http://lh5.ggpht.com/_Rq679ttrduQ/TNDhMxJV7sI/AAAAAAAAELE/_enEMKFoY2U/s400/DSC04950.JPG"> <img src="https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTNDhMxJV7sI%2FAAAAAAAAELE%2F_enEMKFoY2U%2Fs400%2FDSC04950.JPG" id="image_b79b78aac1a6ac8aa2bc5dd046298aa2" alt="DSC04950.JPG" title="DSC04950.JPG"/> </a> </div> </noscript> </div> <div class="mod_embed_images_info " id="info_b79b78aac1a6ac8aa2bc5dd046298aa2" > <a id="link_b79b78aac1a6ac8aa2bc5dd046298aa2" href="http://lh5.ggpht.com/_Rq679ttrduQ/TNDhMxJV7sI/AAAAAAAAELE/_enEMKFoY2U/s400/DSC04950.JPG">DSC04950.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('b79b78aac1a6ac8aa2bc5dd046298aa2', 'https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTNDhMxJV7sI%2FAAAAAAAAELE%2F_enEMKFoY2U%2Fs400%2FDSC04950.JPG', 'http://lh5.ggpht.com/_Rq679ttrduQ/TNDhMxJV7sI/AAAAAAAAELE/_enEMKFoY2U/s400/DSC04950.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTNDhMxJV7sI%2FAAAAAAAAELE%2F_enEMKFoY2U%2Fs400%2FDSC04950.JPG', '', 65320, 800, 400, 'Loading image ...', false);</script><br />I currently have the mounting holes on the aluminum tapped for M4 screws. it's a bit annoying when attaching to the carriage, but helps keep everything tight until it is attached to the carriage. And you will need M4x20 screws; 16mm screws are just a bit too short and don't engage the captive nut.<br /><br />very little heat moves up the tubing, but the aluminum and stack of washers should dissipate the heat that does.<br/>]]></description> <dc:creator>Buback</dc:creator> <category>General</category> <pubDate>Wed, 03 Nov 2010 00:48:42 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65316#msg-65316</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65316#msg-65316</link> <description><![CDATA[ Running the glass bead around the middle of the tub will take a little practice, but once perfected would make the strongest connection. You could even put springs on the vertical bolts to handle thermal expansion. The second approach should work, and will likely work better with roughed up edges for the ferrul to grip. On the other hand, the flange at the end is easier, I just need to work on getting it straight and even. And that should be the strongest. <br /><br /> <a href="http://www.mcmaster.com/#washers/=9juvta" target="_blank" rel="nofollow">PTFE washers</a> are inexpensive from mcmasters. The larger outside diameter would fit well against the flanged end. I will see if I can get you one of each to experiment with.<br /><br />Mike]]></description> <dc:creator>rocket_scientist</dc:creator> <category>General</category> <pubDate>Tue, 02 Nov 2010 23:35:14 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65269#msg-65269</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65269#msg-65269</link> <description><![CDATA[ yeah i'll have to use some sort of gasket. i'm getting leaks; damn thermal expansion!<br /><br />I was hoping that the compression fitting would allow the use of unworked glass, but it seems like it will be a hassle to work out all the kinks. the aluminum expands slightly too much, so i have to tighten the fitting a bit too much, which will eventually lead to fractures in the glass. <br /><br />I think it is a great low skill level solution, since at most it only requires cutting the glass to length (which is tricky, but probably only takes a couple cuts to get a adequate piece). the problem is that, being low-cost/low-skill level, it will inevitably require more maintenance.<br /><br />For further development, i'm going to try isolating the compression fitting a bit from the heater. i'm hoping that if i keep it cool enough it won't expand enough to slip off. <br /><br />I've attached two other designs for evaluation. just quick MS paint doodles. please take a look and tell me what you think.<br />-block3.jpg - in this design, there is a glass bead around the tube. rocket_scientists work shows that this should be pretty easy to do, with the right equipment. definatly not a low-skill option, and would require a finalized design in order to put the bead in the right place. <br />-block4.jpg - this design isolates the compression fitting further up the glass tube in order to keep it cool.]]></description> <dc:creator>Buback</dc:creator> <category>General</category> <pubDate>Tue, 02 Nov 2010 12:37:33 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65208#msg-65208</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65208#msg-65208</link> <description><![CDATA[ Just had an idea. When pressing the replaceable orifice against the glass, it is hard to get a precise fit to prevent leaks. What about using PTFE or PEET washer as a gasket? It should be good through the entire temperature range, and compliant enough to seal the gaps if everything to smooth and clean.<br /><br />Mike]]></description> <dc:creator>rocket_scientist</dc:creator> <category>General</category> <pubDate>Mon, 01 Nov 2010 14:21:29 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65057#msg-65057</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65057#msg-65057</link> <description><![CDATA[ I think that would be ok, but but i see a couple problems to overcome:<br />-The ring has to be big enough to slide over the end of the tube. the compression fitting then has to squeeze it into the notch, which might be a lot of travel. <br />-I just assemble the plates, start the screws so it doesn't fall to pieces, and then set it on a table, orifice-down. then i push down on the glass and tighten the screws. this ensures that the glass is butted against the bottom plate and there are no gaps. A notch would have to be ground in very closely to where the ring will sit in order to prevent a gap. If you have the ability to do this, and a block of aluminum, i'd forgo the ring entirely, grind two troughs 180 degrees opposed, and just put two screws into the block<br /><br /><br />That being said, on lunch break i went home and abraded the glass some with a diamond dremel bit, and then really cranked down on the screws. wired it all up and i got some extrusion, and the block didn't slide off. At least not yet. Also, last night i put a drill bit into the block, in place of the glass, and cranked down the screws, hoping the form the ferrule a bit more to match the shape of the cutout it fits in. that may have helped as well.]]></description> <dc:creator>Buback</dc:creator> <category>General</category> <pubDate>Fri, 29 Oct 2010 17:17:14 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65052#msg-65052</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65052#msg-65052</link> <description><![CDATA[ I dont know much about the glass grinding process, but would it be possible to grind a notch in the glass that the compression O-ring could rest in? That would give some mechanical stability for the heater block rather than just relying on friction on the relatively smooth glass.]]></description> <dc:creator>Greg Frost</dc:creator> <category>General</category> <pubDate>Fri, 29 Oct 2010 16:00:10 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65037#msg-65037</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65037#msg-65037</link> <description><![CDATA[ Unless I left some hidden thermal stress, the glass should be quite strong. Especially with a balanced force around the circumference. However, if you break a nozzle following my instructions, I will send a replacement to continue experimenting with. I still think that some form a glass based nozzle is the way we eventually want to go.<br /><br />Mike]]></description> <dc:creator>rocket_scientist</dc:creator> <category>General</category> <pubDate>Fri, 29 Oct 2010 11:05:06 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,65012#msg-65012</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,65012#msg-65012</link> <description><![CDATA[ yeah i understood you, but i still think my available tooling will be a problem. If i don't drill the countersink perfectly centered, the pieces won't butt against each other and the gap will fill with plastic. I think that you would have to make a matched set of glass and nozzle.<br />---<br />I wired up my hot end and gave it a test earlier. The result?: it slid right off after about 3mm of extrusion out the orifice. :-(<br />I think I misunderstood how the thermal expansion would affect the aluminum block. I thought that, if anything, the hole that the glass goes through would get smaller; in other words, it would expand into the hole, almost like the whole block was swelling. I think it's expanding more like a balloon, where it's just scaling up as it expands, and the hole gets bigger.<br /><br />if this is the case I'll have to put a lot more force on the compression ferrule in the cold state in order to get any grip when hot. I don't know how much compressive force the glass can take around it's circumference like that. perhaps i'll try abrading the surface of the glass near the bottom, where it grips, and see if that does any good. <br /><br />this test makes it more likely that a flange will be needed if going with a metal orifice design. I think a compressive fitting at the top will be fine, though, as long as it's far enough away from the heater (how far is that? no clue, yet)]]></description> <dc:creator>Buback</dc:creator> <category>General</category> <pubDate>Fri, 29 Oct 2010 03:06:51 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64994#msg-64994</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64994#msg-64994</link> <description><![CDATA[ Buback,<br /> I wasn't cleat in my last post. In this case, I was referring not to the drawn out nozzles that I have made, but an unmodified glass tube that is ground down to a cone shape so that it will seal against a brass bolt with a similar taper countersink. I have attached a crude drawing of what I was thinking of. I tried doing this in Google Sketch, but it was faster in Word to do a 2D drawing.<br /><br /> I think there may some advantage to this approach. The metal will be better at heating the plastic, and the hottest part of plastic will be the part inside the narrow orifice. The glass will insulate the incoming filament to minimize the melt zone. With an all-glass nozzle, the friction will be less, but the hottest part is in the middle, the tip tends to cool off.<br /><br />I am currently pushing to get my McWire built and running, so I may not work on making one of these for awhile, but I think this variation is worth a test.<br /><br />Mike]]></description> <dc:creator>rocket_scientist</dc:creator> <category>General</category> <pubDate>Thu, 28 Oct 2010 16:41:38 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64978#msg-64978</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64978#msg-64978</link> <description><![CDATA[ rocket_scientist Wrote:<br />-------------------------------------------------------<br />> I have a glass<br />> grinder, so I can grind down the flange to 8mm. I<br />> can also make you one with a tapered tip that id<br />> larger than 1mm so that different nozzle plates<br />> can be pressed against it and still seal fairly<br />> well.<br /><br />That would be great! I'm not sure about the tapered tip though; while it's a great idea, i don't have the tooling to match the taper. <br /><br />Once my mendel is printing i'm hoping i can improve some of the tools i have at hand.<br />--<br />A solid block would defiantly be better. Once i can find a thick piece of aluminum i'll try it. here's a revised sketch(attached). <br /><br />For the screw in nozzle: it might be difficult to drill into a bolt with such a tiny bit. I was thinking a larger diameter anyway, like 8mm. some leftover studding would work, but the steel drilling would still be a problem (maybe. I don't have much experience with drilling such small holes). Brass M8 bolts?<br /><br />if you cut or grind two flats on the part of the nozzle that protrudes from the block, you could use a small crescent wrench, maybe even the same size as the wrench included with a dremel.<br /><br />the removable nozzle would also make cleaning out clogs easier.]]></description> <dc:creator>Buback</dc:creator> <category>General</category> <pubDate>Thu, 28 Oct 2010 11:39:15 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64942#msg-64942</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64942#msg-64942</link> <description><![CDATA[ Buback,<br /> Do you need a different nozzle? I have a glass grinder, so I can grind down the flange to 8mm. I can also make you one with a tapered tip that id larger than 1mm so that different nozzle plates can be pressed against it and still seal fairly well.<br /><br />The idea of putting a metal plate on the very bottom to create the orifice and heat the plastic right at the tip is good. I will have to try one of those too. For a screw in orifice, you can not use a set screw because it has the inside hole for the allen wrench. But a very short hex head bolt could be drilled for orifice size and then screwed into the bottom plate. I have some thicker blocks of aluminum that I can drill to fit over the glass, and have threading on the bottom to take a short bolt with an orifice drilled into it. Then the heater resistor and thermocouple can be bolted to the block of aluminum, and maybe some tape or insulation wrapped around that.<br /><br />Mike]]></description> <dc:creator>rocket_scientist</dc:creator> <category>General</category> <pubDate>Wed, 27 Oct 2010 19:18:26 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64928#msg-64928</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64928#msg-64928</link> <description><![CDATA[ An update on my previous ideas:<br />My mendel is done! it sings and dances, but still needs a hot end. <br />Here is my progress so far.<br /><div id="div_3be643818120401d0638a5011d0d6d14" class="mod_embed_images" > <div id="imagediv_3be643818120401d0638a5011d0d6d14" class="mod_embed_images_image" > <noscript> <div> <a href="http://lh3.ggpht.com/_Rq679ttrduQ/TMhiQPDasWI/AAAAAAAAEJ8/-s5ML0FJ2t0/s288/DSC04934.JPG"> <img src="https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh3.ggpht.com%2F_Rq679ttrduQ%2FTMhiQPDasWI%2FAAAAAAAAEJ8%2F-s5ML0FJ2t0%2Fs288%2FDSC04934.JPG" id="image_3be643818120401d0638a5011d0d6d14" alt="DSC04934.JPG" title="DSC04934.JPG"/> </a> </div> </noscript> </div> <div class="mod_embed_images_info " id="info_3be643818120401d0638a5011d0d6d14" > <a id="link_3be643818120401d0638a5011d0d6d14" href="http://lh3.ggpht.com/_Rq679ttrduQ/TMhiQPDasWI/AAAAAAAAEJ8/-s5ML0FJ2t0/s288/DSC04934.JPG">DSC04934.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('3be643818120401d0638a5011d0d6d14', 'https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh3.ggpht.com%2F_Rq679ttrduQ%2FTMhiQPDasWI%2FAAAAAAAAEJ8%2F-s5ML0FJ2t0%2Fs288%2FDSC04934.JPG', 'http://lh3.ggpht.com/_Rq679ttrduQ/TMhiQPDasWI/AAAAAAAAEJ8/-s5ML0FJ2t0/s288/DSC04934.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Flh3.ggpht.com%2F_Rq679ttrduQ%2FTMhiQPDasWI%2FAAAAAAAAEJ8%2F-s5ML0FJ2t0%2Fs288%2FDSC04934.JPG', '', 64928, 800, 400, 'Loading image ...', false);</script><br /><div id="div_32e85fa1addb0badef23fbd667465d25" class="mod_embed_images" > <div id="imagediv_32e85fa1addb0badef23fbd667465d25" class="mod_embed_images_image" > <noscript> <div> <a href="http://lh6.ggpht.com/_Rq679ttrduQ/TMhiQfawbuI/AAAAAAAAEKE/mqjHHVvyXBU/s288/DSC04933.JPG"> <img src="https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh6.ggpht.com%2F_Rq679ttrduQ%2FTMhiQfawbuI%2FAAAAAAAAEKE%2FmqjHHVvyXBU%2Fs288%2FDSC04933.JPG" id="image_32e85fa1addb0badef23fbd667465d25" alt="DSC04933.JPG" title="DSC04933.JPG"/> </a> </div> </noscript> </div> <div class="mod_embed_images_info " id="info_32e85fa1addb0badef23fbd667465d25" > <a id="link_32e85fa1addb0badef23fbd667465d25" href="http://lh6.ggpht.com/_Rq679ttrduQ/TMhiQfawbuI/AAAAAAAAEKE/mqjHHVvyXBU/s288/DSC04933.JPG">DSC04933.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('32e85fa1addb0badef23fbd667465d25', 'https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh6.ggpht.com%2F_Rq679ttrduQ%2FTMhiQfawbuI%2FAAAAAAAAEKE%2FmqjHHVvyXBU%2Fs288%2FDSC04933.JPG', 'http://lh6.ggpht.com/_Rq679ttrduQ/TMhiQfawbuI/AAAAAAAAEKE/mqjHHVvyXBU/s288/DSC04933.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Flh6.ggpht.com%2F_Rq679ttrduQ%2FTMhiQfawbuI%2FAAAAAAAAEKE%2FmqjHHVvyXBU%2Fs288%2FDSC04933.JPG', '', 64928, 800, 400, 'Loading image ...', false);</script><br />(you can see that there is a .5 mm gap between plates 4 and 3. This is because i haven't cranked down on the screws; i'm scared of breaking the glass. the other 3 plates have no gaps between them. what looks like a gap between plates 1 and 2 is actually just a shadow from a horrible cutting job.)<br /><div id="div_a0c582df4e555b43c6fc06ed63cb0cbb" class="mod_embed_images" > <div id="imagediv_a0c582df4e555b43c6fc06ed63cb0cbb" class="mod_embed_images_image" > <noscript> <div> <a href="http://lh5.ggpht.com/_Rq679ttrduQ/TMhiQu1OMEI/AAAAAAAAEKM/PkUoOqfiipo/s288/DSC04930.JPG"> <img src="https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTMhiQu1OMEI%2FAAAAAAAAEKM%2FPkUoOqfiipo%2Fs288%2FDSC04930.JPG" id="image_a0c582df4e555b43c6fc06ed63cb0cbb" alt="DSC04930.JPG" title="DSC04930.JPG"/> </a> </div> </noscript> </div> <div class="mod_embed_images_info " id="info_a0c582df4e555b43c6fc06ed63cb0cbb" > <a id="link_a0c582df4e555b43c6fc06ed63cb0cbb" href="http://lh5.ggpht.com/_Rq679ttrduQ/TMhiQu1OMEI/AAAAAAAAEKM/PkUoOqfiipo/s288/DSC04930.JPG">DSC04930.JPG</a> </div> </div> <script type="text/javascript">mod_embed_images_loadimage('a0c582df4e555b43c6fc06ed63cb0cbb', 'https://reprap.org/forum/addon.php?1,module=embed_images,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTMhiQu1OMEI%2FAAAAAAAAEKM%2FPkUoOqfiipo%2Fs288%2FDSC04930.JPG', 'http://lh5.ggpht.com/_Rq679ttrduQ/TMhiQu1OMEI/AAAAAAAAEKM/PkUoOqfiipo/s288/DSC04930.JPG', 'https://reprap.org/forum/addon.php?1,module=embed_images,check_scaling=1,url=http%3A%2F%2Flh5.ggpht.com%2F_Rq679ttrduQ%2FTMhiQu1OMEI%2FAAAAAAAAEKM%2FPkUoOqfiipo%2Fs288%2FDSC04930.JPG', '', 64928, 800, 400, 'Loading image ...', false);</script><br />(i drilled the hole for the resistor after i took this last picture, and even though the holes don't look like they line up, they do when properly aligned)<br /><br />As you can see, i only am using 4 plates (badly cut, but i only have a hacksaw to work with)<br />the top two plates are for a homemade compression fitting. i used a piece of copper wire, but it is too thick so i had to work it down to size. Not ideal. i'll get smaller wire eventually.<br />the 3rd plate is a spacer. if you add another spacer, you could place two resistors on each side of the tube horizontally,, drilling a hole between these two spacers. But my arm was tired from cutting the other 4, so i put my resistor vertically :-)<br />The bottom plate is tapped for 2 m3 bolts. I drilled the center, where the orifice will go, about half way through with a 3mm bit (actually whatever the closest fractional SAE bit is)<br /><br />my drill press is laughable and just barely adequate for the big holes. I have a .4 mm drill bit for the orifice, but am scared to use it :-)<br /><br />Maybe a jeweler has an adequate drill press? I'll call around.<br /><br />One benefit of this design is that the bottom plate can be switched out in order to change orifice size. it would be even better to have a screw in orifice. If i can get a drill press good enough for these micro bit sizes, i'll experiment with that. <br /><br />The filament is also in direct contact with the aluminum, and the orifice is aluminum, which seems like it will transfer heat better.<br /><br />Rocket_scientist sent me a flanged glass tube to experiment with the "flange inside the block" idea, but the flange has about an 10 mm diameter. ideally, it would be 8mm or less, and only as tall as one layer (3mm). i think a perfect flange would be ground to the proper dimensions.<br /><br />The compression fitting holds very well, though, so i don't know if it's worth the extra labor. however, i haven't tried heating or extruding yet. i may find that the compression fitting breaks the glass, or the pressure of the filament slides off the block.<br /><br />(Also, i was naive to think that a conical bit, like a countersink bit, would drill. all it does is spin and spin, since there are no cutting faces at the apex.)<br/>]]></description> <dc:creator>Buback</dc:creator> <category>General</category> <pubDate>Wed, 27 Oct 2010 15:49:12 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64336#msg-64336</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64336#msg-64336</link> <description><![CDATA[ Driving it with DC on nichrome is basically what we are doing now. If I could get the wire embedded in the inside of the glass tube, I would be happily promoting that. It would be a great way to do it with glass. But I have not yet figured out how to embed the nichrome wire in the glass without burning up the nichrome in the torch flame, let alone putting it on the inside without adding ridges to increase the friction of the plastic going through. Nichrome is an alloy of nickel, chrome, and copper so I doubt it can be electroplated on. I think we will have to stick with copper electroplated on for the smoothest induction heated element.<br /><br />Mike]]></description> <dc:creator>rocket_scientist</dc:creator> <category>General</category> <pubDate>Wed, 20 Oct 2010 20:34:16 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64325#msg-64325</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64325#msg-64325</link> <description><![CDATA[ Well, I'm hoping to <i>avoid</i> heating the glass directly, in order to achieve a sharper hot-cold transition zone...]]></description> <dc:creator>jbayless</dc:creator> <category>General</category> <pubDate>Wed, 20 Oct 2010 17:33:26 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64323#msg-64323</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64323#msg-64323</link> <description><![CDATA[ Could you do induction as you are planning with a high resistance primary driven at high frequency?<br /><br />eg: Would you gain any effect making the primary out of nichrome, thereby having the option to heat the glass on the inside AND the outside?<br /><br />Just thinking it might be possible to drive this with DC to get the glass close to temp/warm, then drive it with high frequency AC to keep it there using induction heating.<br /><br />I've not tried this, so it may not even be possible. Was just a thought.]]></description> <dc:creator>Cefiar</dc:creator> <category>General</category> <pubDate>Wed, 20 Oct 2010 17:29:10 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64313#msg-64313</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64313#msg-64313</link> <description><![CDATA[ Not only is there the skin effect, there's also the fact that you can just pump a ton of current through the copper until it heats up. Having a small number of turns on the primary winding will induce a small voltage in the secondary, and for a low-resistance secondary, that should result in an extremely high current.<br /><br />I'm stil working through the math. I hope to soon have a closed-form expression for the power in the secondary, and the voltage across the primary, as a function of all the relevant parameters.]]></description> <dc:creator>jbayless</dc:creator> <category>General</category> <pubDate>Wed, 20 Oct 2010 13:49:09 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64304#msg-64304</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64304#msg-64304</link> <description><![CDATA[ Good point nophead! I remember most of the diagrams should copper tubing, not copper wire, to make up the 20 turn primary. Since the same frequency occurs there, it would also need as much skin as it can get without being heavy.<br /><br />I still think that what ever conductor is deposited on the inside of the glass must be thick to carry the thermal load, even if the skin effect makes the effective electrical resistance high. It will also need to be thick to keep from peeling off the glass due to differential thermal expansion.<br /><br />The next question is, is it possible to make a SPIRAL pattern of silver, and run one end out the tip and the other out the big end and plate it with enough copper to do straight resistance heating? <br /><br />Mike]]></description> <dc:creator>rocket_scientist</dc:creator> <category>General</category> <pubDate>Wed, 20 Oct 2010 10:54:11 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64274#msg-64274</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64274#msg-64274</link> <description><![CDATA[ Induction heating can heat good conductors, you just have to use a high frequency to exploit the skin effect. That means all the current flows in a very thin layer at the surface regardless of how thick the material is. At a few tens of kHz the skin effect dominates.]]></description> <dc:creator>nophead</dc:creator> <category>General</category> <pubDate>Wed, 20 Oct 2010 05:24:28 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64269#msg-64269</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64269#msg-64269</link> <description><![CDATA[ That's a good point, unless the film is thin enough to offset. And I think silver is an even better conductor.<br /><br />Not sure whether the plating would carry enough heat from an external coil to the tip and interior of the nozzle to be worth it.<br /><br />I'll leave a few experiments on my TODO list, but it's probably not worth anyone else's time.]]></description> <dc:creator>crlfe</dc:creator> <category>General</category> <pubDate>Wed, 20 Oct 2010 02:44:08 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64263#msg-64263</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64263#msg-64263</link> <description><![CDATA[ I don't think copper will work. Copper has a too low resistance to be heated by induction. No resistance no heat...<br /><br />Klaus]]></description> <dc:creator>fks</dc:creator> <category>General</category> <pubDate>Wed, 20 Oct 2010 01:53:58 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64149#msg-64149</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64149#msg-64149</link> <description><![CDATA[ I had not thought of chemically plating silver on the inside of the glass. That would maintain the efficient shape of the glass. And once a good layer of silver has been deposited, you can switch to electroplating copper onto the silver to get a less expensive thick layer to carry all the heating current. That would make the inductive heating approach work well for everything accept monitoring the temperature, and we are current wondering if that can be done with non-contact IR thermometer, so that would complete the system. Still seems overly complex to me, but I will see about giving it a shot when I get the chance.<br /><br /> I have looked for IR sensors, and they seem to be a bit expensive. But if I buy a whole unit, with digital read out from Harbor Freight, then I can get something that will cover the whole temp range needed for $25. I will hopefully be posting a hack into the HF thermometer to get either an analog or digital signal to the control electronics posted soon.<br /><br />Mike]]></description> <dc:creator>rocket_scientist</dc:creator> <category>General</category> <pubDate>Mon, 18 Oct 2010 17:32:13 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64135#msg-64135</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64135#msg-64135</link> <description><![CDATA[ If you are looking to order in quantity, you can just have something custom made. I got a quote from a company called chemglass a couple weeks ago:<br /><br />Tapered, Borosilicate Type Glass Tubes, 6mm OD x 3mm ID x 60mm Overall Length, Will Have Tapered End With a 0.4mm ID +/- 0.2mm, Other End Will Be Open and Fire Polished<br />it would be $3.50 each for 200+<br />On the other hand, they quoted $96 for a sample of 3 pieces minimum]]></description> <dc:creator>Buback</dc:creator> <category>General</category> <pubDate>Mon, 18 Oct 2010 14:32:08 -0400</pubDate> </item> <item> <guid>https://reprap.org/forum/read.php?1,53676,64129#msg-64129</guid> <title>Re: Glass nozzles for extruders</title> <link>https://reprap.org/forum/read.php?1,53676,64129#msg-64129</link> <description><![CDATA[ I'll have to wait and prod a chemist friend to get exact specs and samples to test. However they should be dirt cheap: the closest match I found on my quick search was the Chase 63A14673-010, which runs $75 per 1000.<br /><br />Edit: Not to say that it's a particularly good match. However something 10x the price is still peanuts.]]></description> <dc:creator>crlfe</dc:creator> <category>General</category> <pubDate>Mon, 18 Oct 2010 13:36:12 -0400</pubDate> </item> </channel></rss> If you would like to create a banner that links to this page (i.e. this validation result), do the following:
Download the "valid RSS" banner.
Upload the image to your own server. (This step is important. Please do not link directly to the image on this server.)
Add this HTML to your page (change the image src attribute if necessary):
If you would like to create a text link instead, here is the URL you can use:
