Quote from firepinto on November 18th, 2011, 08:08 PM

Hey Jeff,
Hows the printing going?  Have you been able to get your heated plate fired up yet?  

Nate
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Hi Nate, I have printed nickle gauges, belt tension brackets and small gears, :D none of which have been good.:(  I did some rework on my extruder tip or orifice,:idea: made the very tip a little longer so it won't catch the filament if it curls up, also having trouble with the hotend plugging up,:(  I need to check the temp with a temp meter to see if the temp is what pronterface say's it is. I made another barrel closer to the size of pla filament, I will install the new tip and barrel tomorrow after I run some tests without the heatsink and fan on the hotend, it could be cooling it off to quickly, just have to wait and see. How do you lower the temp, is that in sprinter or pronterface? How is the bobbin coming?:D  I have not done anything on the heated plate yet,:(  I just received some abs filament, when I get the hotend all fixed and printing good without plugging up :D I will be starting on the heated plate, that's it for now, thanks Nate.

Well, nothing I have tried thus far has worked to keep my hotend from plugging up or jamming:( , temperature is fine I checked it with another meter :D. While the hotend is on or heating, I noticed the filament diameter increases before it goes into the barrel of the hotend [ while still in the peek ], the E drive reverses direction, so X and Y can move the hotend to another location, it's at this point the filament cools bit, when the E drive goes back to the filament feed direction, the filament jambs and will not feed any more :huh:, to fix this problem :idea:  I will need to drill another piece of peek with a smaller inside diameter hole so the filament diameter when melting, will be smaller than the inside diameter of the barrel, then hopefully the filament will feed properly. :D

Quote from Jeff Nading on November 20th, 2011, 07:36 AM

Well, nothing I have tried thus far has worked to keep my hotend from plugging up or jamming:( , temperature is fine I checked it with another meter :D. While the hotend is on or heating, I noticed the filament diameter increases before it goes into the barrel of the hotend [ while still in the peek ], the E drive reverses direction, so X and Y can move the hotend to another location, it's at this point the filament cools bit, when the E drive goes back to the filament feed direction, the filament jambs and will not feed any more :huh:, to fix this problem :idea:  I will need to drill another piece of peek with a smaller inside diameter hole so the filament diameter when melting, will be smaller than the inside diameter of the barrel, then hopefully the filament will feed properly. :D

I may have had a similar situation one time, but I left the hot end set to 185 while not printing.  I know my filament gets a small bulb at the end of it when I pull it out of the extruder cold.  Maybe the barrel needs a small cone shape inside?  I never really looked into my makergear hot end to see what it was like inside.  I have mine dialed in really good right now... its like I don't even want to breathe on it till I finish printing these bobbins.:P  

Nate

Quote from firepinto on November 20th, 2011, 07:59 PM

Quote from Jeff Nading on November 20th, 2011, 07:36 AM

Well, nothing I have tried thus far has worked to keep my hotend from plugging up or jamming:( , temperature is fine I checked it with another meter :D. While the hotend is on or heating, I noticed the filament diameter increases before it goes into the barrel of the hotend [ while still in the peek ], the E drive reverses direction, so X and Y can move the hotend to another location, it's at this point the filament cools bit, when the E drive goes back to the filament feed direction, the filament jambs and will not feed any more :huh:, to fix this problem :idea:  I will need to drill another piece of peek with a smaller inside diameter hole so the filament diameter when melting, will be smaller than the inside diameter of the barrel, then hopefully the filament will feed properly. :D

I may have had a similar situation one time, but I left the hot end set to 185 while not printing.  I know my filament gets a small bulb at the end of it when I pull it out of the extruder cold.  Maybe the barrel needs a small cone shape inside?  I never really looked into my makergear hot end to see what it was like inside.  I have mine dialed in really good right now... its like I don't even want to breathe on it till I finish printing these bobbins.:P  

Nate

Hi Nate, I'm uploading a video of my printer finally printing:cool: :D . The work I did on the hotend paid off :P , it works without jamming now. All I need to do is rework the print bed a little to heat it, then I will try printing abs. What do you have your E drive speed set at? You could be right about the cone shape in the barrel.:D

Here,s a new video of my 3d printer printing.https://www.youtube.com/watch?v=dfbtfSxWr30

Made more hotends.

Nate just wanted to show off your hotends, they are both wired, connected them one at a time to my printer and let them heat up to abs temperature to temper the oven cement, they both pull 1.91 amps, the 1.84 was one I built for myself. they are both matched well, pulling the same amperage, 1.91 amps. They work very well heating up. Send photo's later.

Quote from Jeff Nading on November 26th, 2011, 08:19 PM

Nate just wanted to show off your hotends, they are both wired, connected them one at a time to my printer and let them heat up to abs temperature to temper the oven cement, they both pull 1.91 amps, the 1.84 was one I built for myself. they are both matched well, pulling the same amperage, 1.91 amps. They work very well heating up. Send photo's later.

Cool Jeff,  you got the tiny holes done already?  How long does the cement take to temper?

Nate

Here are the photos of Nate's hotends. I have not yet drilled the orifice holes, it took about 10 minutes to temper each hotend.:D

 Nate, here is what I'm going to do to build the heated bed, linked here
http://hydraraptor.blogspot.com/2010/01/hot-bed.html , they say it will use 12 volts @ 9 amps, :cool: so this means we can connect the bed directly to the ramps board, no external power supply, controlling the temp - same as well. I think this will be a good solution, what do you think?:D

Quote from Jeff Nading on November 27th, 2011, 06:43 AM

Nate, here is what I'm going to do to build the heated bed, linked here
http://hydraraptor.blogspot.com/2010/01/hot-bed.html , they say it will use 12 volts @ 9 amps, :cool: so this means we can connect the bed directly to the ramps board, no external power supply, controlling the temp - same as well. I think this will be a good solution, what do you think?:D

I'm going to call Digi-key tomorrow and maybe order the resistors, link
http://search.digikey.com/us/en/products/2-1879073-2/2-1879073-2-ND/2366855

Quote from Jeff Nading on November 27th, 2011, 08:02 AM

Quote from Jeff Nading on November 27th, 2011, 06:43 AM

Nate, here is what I'm going to do to build the heated bed, linked here
http://hydraraptor.blogspot.com/2010/01/hot-bed.html , they say it will use 12 volts @ 9 amps, :cool: so this means we can connect the bed directly to the ramps board, no external power supply, controlling the temp - same as well. I think this will be a good solution, what do you think?:D

I'm going to call Digi-key tomorrow and maybe order the resistors, link
http://search.digikey.com/us/en/products/2-1879073-2/2-1879073-2-ND/2366855

Looks like it could work good.  I see that he had problems with the warm up time being 15 minutes while using 12 volts dc.  He went up to 48 volts AC to speed up the time and get more efficiency.  

I was thinking about creating pockets on the back side of the bed to cement resistors flush into the material.  Not sure how thermally conductive the cement is, but at least then more sides of the resistor have contact with the aluminum.  Maybea better idea is to create channels that those style of resistors could be mounted up side down in.  More contact would mean faster warm up time?  

Before I try try resistors I'm going to pick up a couple of these:
http://www.amazon.com/Kats-24100-Watt-Universal-Heater/dp/B000I8VL3O
I'll have to drive a relay with the ramps and wire a ground to the plate just to be safe from 120 VAC shocks.  A GFCI outlet would be a good idea too.:P  
EDIT: Just researched the Kat's heating pads, they are thermostatically controlled to 159F / 70C.  Not quite the 100C they talk about on that page.  Still would work?  Not sure.

I also want to try to reduce the weight of the plate by drilling pockets either from the sides or from the bottom.  I'll only do that if it becomes a problem.  I have an idea in the works to give our Y motors more power, so that might not be needed.:D  The muscle car of RepRaps?

Nate

Quote from firepinto on November 27th, 2011, 10:47 AM

Quote from Jeff Nading on November 27th, 2011, 08:02 AM

Quote from Jeff Nading on November 27th, 2011, 06:43 AM

Nate, here is what I'm going to do to build the heated bed, linked here
http://hydraraptor.blogspot.com/2010/01/hot-bed.html , they say it will use 12 volts @ 9 amps, :cool: so this means we can connect the bed directly to the ramps board, no external power supply, controlling the temp - same as well. I think this will be a good solution, what do you think?:D

I'm going to call Digi-key tomorrow and maybe order the resistors, link
http://search.digikey.com/us/en/products/2-1879073-2/2-1879073-2-ND/2366855

Looks like it could work good.  I see that he had problems with the warm up time being 15 minutes while using 12 volts dc.  He went up to 48 volts AC to speed up the time and get more efficiency.  

I was thinking about creating pockets on the back side of the bed to cement resistors flush into the material.  Not sure how thermally conductive the cement is, but at least then more sides of the resistor have contact with the aluminum.  Maybea better idea is to create channels that those style of resistors could be mounted up side down in.  More contact would mean faster warm up time?  

Before I try try resistors I'm going to pick up a couple of these:
http://www.amazon.com/Kats-24100-Watt-Universal-Heater/dp/B000I8VL3O
I'll have to drive a relay with the ramps and wire a ground to the plate just to be safe from 120 VAC shocks.  A GFCI outlet would be a good idea too.:P  
EDIT: Just researched the Kat's heating pads, they are thermostatically controlled to 159F / 70C.  Not quite the 100C they talk about on that page.  Still would work?  Not sure.

I also want to try to reduce the weight of the plate by drilling pockets either from the sides or from the bottom.  I'll only do that if it becomes a problem.  I have an idea in the works to give our Y motors more power, so that might not be needed.:D  The muscle car of RepRaps?

Nate

Say Nate, I just wanted to tell you, don't feel obligated to use the aluminum plate I made for you,:D it was just a thought and might not work out, or end up costing more time and money than it's worth, so if you want to buy one of though's really nice heated bed plates go ahead,:cool: you will not hurt my feelings at all,:D I might do the same. I did think of using 15 ohm 10 watt resistors instead of 12 ohm, I think that would speed up the heating process, still using 12 volts.:idea: What do you think? I sent you an email but don't know if it went through, so I'll say it here to, I ordered 2' x  5/8" dia. peek rod today:P $70.00 worth,:( I also got the drill bits I needed .34mm instead of .35mm,:P to drill the holes for the extruder tips, so maybe the extruders will be waiting for you when you get home:D:cool: Hope your doing well.

Quote from Jeff Nading on November 28th, 2011, 07:22 PM

Quote from firepinto on November 27th, 2011, 10:47 AM

Quote from Jeff Nading on November 27th, 2011, 08:02 AM

Quote from Jeff Nading on November 27th, 2011, 06:43 AM

Nate, here is what I'm going to do to build the heated bed, linked here
http://hydraraptor.blogspot.com/2010/01/hot-bed.html , they say it will use 12 volts @ 9 amps, :cool: so this means we can connect the bed directly to the ramps board, no external power supply, controlling the temp - same as well. I think this will be a good solution, what do you think?:D

I'm going to call Digi-key tomorrow and maybe order the resistors, link
http://search.digikey.com/us/en/products/2-1879073-2/2-1879073-2-ND/2366855

Looks like it could work good.  I see that he had problems with the warm up time being 15 minutes while using 12 volts dc.  He went up to 48 volts AC to speed up the time and get more efficiency.  

I was thinking about creating pockets on the back side of the bed to cement resistors flush into the material.  Not sure how thermally conductive the cement is, but at least then more sides of the resistor have contact with the aluminum.  Maybea better idea is to create channels that those style of resistors could be mounted up side down in.  More contact would mean faster warm up time?  

Before I try try resistors I'm going to pick up a couple of these:
http://www.amazon.com/Kats-24100-Watt-Universal-Heater/dp/B000I8VL3O
I'll have to drive a relay with the ramps and wire a ground to the plate just to be safe from 120 VAC shocks.  A GFCI outlet would be a good idea too.:P  
EDIT: Just researched the Kat's heating pads, they are thermostatically controlled to 159F / 70C.  Not quite the 100C they talk about on that page.  Still would work?  Not sure.

I also want to try to reduce the weight of the plate by drilling pockets either from the sides or from the bottom.  I'll only do that if it becomes a problem.  I have an idea in the works to give our Y motors more power, so that might not be needed.:D  The muscle car of RepRaps?

Nate

Say Nate, I just wanted to tell you, don't feel obligated to use the aluminum plate I made for you,:D it was just a thought and might not work out, or end up costing more time and money than it's worth, so if you want to buy one of though's really nice heated bed plates go ahead,:cool: you will not hurt my feelings at all,:D I might do the same. I did think of using 15 ohm 10 watt resistors instead of 12 ohm, I think that would speed up the heating process, still using 12 volts.:idea: What do you think? I sent you an email but don't know if it went through, so I'll say it here to, I ordered 2' x  5/8" dia. peek rod today:P $70.00 worth,:( I also got the drill bits I needed .34mm instead of .35mm,:P to drill the holes for the extruder tips, so maybe the extruders will be waiting for you when you get home:D:cool: Hope your doing well.

Hey Jeff,
I just got to reply to your email.:)  Its been a long day of flying for me.  :P  I think your aluminum bed will work good.:cool:  I just haven't had time to work on it.  Having it thicker will keep the bed from warping from uneven heating.  With some holes cored into it it will reduce weight, but still keep the strength.  I've been finding that these Prusas have touchy X and Y drives.  A lot of people that have round objects that don't come out round are having problems with friction, like belts dragging on washers and such.  I know I had huge friction problems with my old bronze bushings.  So I think your plate will work like it is, I might just optimize it.:D I'm going to design a new Y motor set up for printing bigger heavier objects.  (like a S.M. WFC:idea:):)
I tend to do more thinking ahead than I do actual work on my printer. lol I wish I could pack it in my luggage.:)

Hi Nate, I just found another heated bed that looks more promising, :cool: linked here,
http://garyhodgson.com/reprap/ , there are  other mods as well, good info. Have you made it home yet?  I'm still working on the hotends :D

Quote from Jeff Nading on December 4th, 2011, 06:52 PM

Hi Nate, I just found another heated bed that looks more promising, :cool: linked here,
http://garyhodgson.com/reprap/ , there are  other mods as well, good info. Have you made it home yet?  I'm still working on the hotends :D

That looks very interesting, I'll have to catch up on reading through it all.:cool:  I like that he's experimenting with new axis designs too.  
Still haven't made it home yet.  Just finished an 83 hour week, and starting a new one tomorrow.:P  I haven't even loaded sketchup once this week:exclamation:  The new printer ideas are still stuck in my grey matter for now.:P    
I tried to remote into my printer cpu, but I think I shut it down before I left home.:(  I was thinking about your hot end on your printer.  When you print does it go good at first but then get really thin extrutions?  If it does I was thinking that maybe the screw on tip isn't staying quite as hot as the threaded barrel.  A bit of processor heat sink silver paste on the threads could improve the heat conduction to the tip.  The reason I was thinking that is I've noticed on mine when it is printing fast, sometimes the hot end has some trouble keeping the temp at 185.  It's like the filament is coolant, the faster it flows the colder the hot end gets.  
Have ya had any better luck?

Nate

Quote from firepinto on December 4th, 2011, 08:21 PM

Quote from Jeff Nading on December 4th, 2011, 06:52 PM

Hi Nate, I just found another heated bed that looks more promising, :cool: linked here,
http://garyhodgson.com/reprap/ , there are  other mods as well, good info. Have you made it home yet?  I'm still working on the hotends :D

That looks very interesting, I'll have to catch up on reading through it all.:cool:  I like that he's experimenting with new axis designs too.  
Still haven't made it home yet.  Just finished an 83 hour week, and starting a new one tomorrow.:P  I haven't even loaded sketchup once this week:exclamation:  The new printer ideas are still stuck in my grey matter for now.:P    
I tried to remote into my printer cpu, but I think I shut it down before I left home.:(  I was thinking about your hot end on your printer.  When you print does it go good at first but then get really thin extrutions?  If it does I was thinking that maybe the screw on tip isn't staying quite as hot as the threaded barrel.  A bit of processor heat sink silver paste on the threads could improve the heat conduction to the tip.  The reason I was thinking that is I've noticed on mine when it is printing fast, sometimes the hot end has some trouble keeping the temp at 185.  It's like the filament is coolant, the faster it flows the colder the hot end gets.  
Have ya had any better luck?

Nate

Ya Nate, that is exactly what is happening on my hotend, except it's the barrel end where it screws into the peek, the filament seems to cold, then seizes in the peek at that point. Last night I shortened the peek about an 1/8" it took longer to seize up so I think I will have to shorten it a little more before it works well. I have been using the heat paste, it does help. I'll try shortening the peek more tonight and see if it helps anymore.

Thought ya might want to see this video on ceramic printing with $1 a pound materials:
http://open3dp.me.washington.edu/2009/10/printing-ceramic-on-youtube/

https://www.youtube.com/watch?v=g3Arud2MBhQ&feature=player_embedded

Could be a way to make a certain thirst solving disk.:P  

Hi Nate, I would like to get the recipe for the ceramic they were using and I liked their kiln.:D As for ceramic printing, I found this video the other day, which would work with our printers, I think I might try this later on.:cool:
https://www.youtube.com/watch?v=_c0C8w_LdYM&feature=results_main&playnext=1&list=PLA5738815356F0C7A    . I was more successful at printing last night,:D finally got my e movement calibrated correctly :D, set at 539 steps in sprinter @ 50 mm's,  slowed the mm's per min. down to 139, machined the 5/8" peek rod down, to work with the hotend, so as not to act as a cooling rod. I will have to tighten the belts more to achieve better resolution, then a few more tweaks here and there and I think I might have it. So, the hotends I made for you should work after I machine the 5/8" peek rod to the design I have on my hotend :D, you will be able to mount the hotends two different ways :cool:, I personally like the pin method, if the hot end is cold you can remove it from your extruder in less than one minute :P. Should have your hotends done and shipped on Monday, hopefully before you need them :D.

Quote from Jeff Nading on December 7th, 2011, 12:41 PM

Hi Nate, I would like to get the recipe for the ceramic they were using and I liked their kiln.:D As for ceramic printing, I found this video the other day, which would work with our printers, I think I might try this later on.:cool:
https://www.youtube.com/watch?v=_c0C8w_LdYM&feature=results_main&playnext=1&list=PLA5738815356F0C7A    . I was more successful at printing last night,:D finally got my e movement calibrated correctly :D, set at 539 steps in sprinter @ 50 mm's,  slowed the mm's per min. down to 139, machined the 5/8" peek rod down, to work with the hotend, so as not to act as a cooling rod. I will have to tighten the belts more to achieve better resolution, then a few more tweaks here and there and I think I might have it. So, the hotends I made for you should work after I machine the 5/8" peek rod to the design I have on my hotend :D, you will be able to mount the hotends two different ways :cool:, I personally like the pin method, if the hot end is cold you can remove it from your extruder in less than one minute :P. Should have your hotends done and shipped on Monday, hopefully before you need them :D.

Cool video.:cool:  Looks like it is part of the design to not move the bed for the Y axis, or the clay would fall over.  
Glad to hear your extruder is working!  Now your going to start enjoying your hard work.:)  I can't wait to get started on building the new printer.  I don't know how soon I will start.  I'm going to be pretty much burned out this weekend.  

Nate

Well Nate, hope you are home now and all is well :D, I was still having trouble with my hotend :(, filament cooling off in the peek rod or seizing up in it :(, so I was thinking I would have to drill out the filament entrance end of the peek and install ptfe to keep the filament from seizing up :), then I found this,

http://www.flickr.com/photos/makergear/5519253034/in/photostream/lightbox/
 this is exactly what they did, I was right :P, needless to say I don't have any ptfe :(, I will order some and install it into your hotends, once this is done, I will ship them to you, I hope you will understand, I want to be fully confident that the hotends will work for you before I ship them out, I am sorry for the delay Nate.

Quote from Jeff Nading on December 9th, 2011, 04:09 PM

Well Nate, hope you are home now and all is well :D, I was still having trouble with my hotend :(, filament cooling off in the peek rod or seizing up in it :(, so I was thinking I would have to drill out the filament entrance end of the peek and install ptfe to keep the filament from seizing up :), then I found this,

http://www.flickr.com/photos/makergear/5519253034/in/photostream/lightbox/
 this is exactly what they did, I was right :P, needless to say I don't have any ptfe :(, I will order some and install it into your hotends, once this is done, I will ship them to you, I hope you will understand, I want to be fully confident that the hotends will work for you before I ship them out, I am sorry for the delay Nate.

Hey Jeff,
No problem at all.:cool: I'm gone away every week from now to Christmas.  You got all the time you need.:D  I'm going to do as much as I can on weekends, but I don't really think I'm going to get much done on the new printer till the last week of the year.

I see what  ya mean about drilling out the entrance.  What is the advantage of the PTFE over PEEK?   Do you think any changes in dimensions are needed if 1.75 mm filament is used in the future?

Quote from firepinto on December 9th, 2011, 05:40 PM

Quote from Jeff Nading on December 9th, 2011, 04:09 PM

Well Nate, hope you are home now and all is well :D, I was still having trouble with my hotend :(, filament cooling off in the peek rod or seizing up in it :(, so I was thinking I would have to drill out the filament entrance end of the peek and install ptfe to keep the filament from seizing up :), then I found this,

http://www.flickr.com/photos/makergear/5519253034/in/photostream/lightbox/
 this is exactly what they did, I was right :P, needless to say I don't have any ptfe :(, I will order some and install it into your hotends, once this is done, I will ship them to you, I hope you will understand, I want to be fully confident that the hotends will work for you before I ship them out, I am sorry for the delay Nate.

Hey Jeff,
No problem at all.:cool: I'm gone away every week from now to Christmas.  You got all the time you need.:D  I'm going to do as much as I can on weekends, but I don't really think I'm going to get much done on the new printer till the last week of the year.

I see what  ya mean about drilling out the entrance.  What is the advantage of the PTFE over PEEK?   Do you think any changes in dimensions are needed if 1.75 mm filament is used in the future?

Ya Nate, I just ordered 3' of 3/8" diameter ptfe from small parts.com :), when I receive it, I will be making you an insert for both sizes of filament, all you would have to do would be to change out the inserted ptfe to the size of filament you want to use :D. Also, the ptfe has a kind of lubricating quality about it, things do not bond to it easily, like filament, so, this being the case, I think the filament will not get stuck to it like it does to the peek [the problem I have been having] :cool:. I just drilled the holes in the extruder nozzles by hand :huh:, orifices are .34 mm, # 80 drill bit, they came out good, I can hardly blow though them, they should work well for fine resolution :cool:. The barrels, I machined in such a way so as to seal them selves inside the extruder nozzles when I screwed them in, this worked as well, they do hold pressure, so as not to leak filament between the threads :cool:, the peek holds the same pressure, this is important when extruding plastic correctly. The hotend elements are then screwed onto the barrels with heat sink paste on the treads and between the extruder nozzles and the elements, there should not be any concerns of a cold nozzle. I think you will have some good hotends when all is said and done, at least I hope so.:P:D:cool:

Quote from Jeff Nading on December 9th, 2011, 07:16 PM

Quote from firepinto on December 9th, 2011, 05:40 PM

Quote from Jeff Nading on December 9th, 2011, 04:09 PM

Well Nate, hope you are home now and all is well :D, I was still having trouble with my hotend :(, filament cooling off in the peek rod or seizing up in it :(, so I was thinking I would have to drill out the filament entrance end of the peek and install ptfe to keep the filament from seizing up :), then I found this,

http://www.flickr.com/photos/makergear/5519253034/in/photostream/lightbox/
 this is exactly what they did, I was right :P, needless to say I don't have any ptfe :(, I will order some and install it into your hotends, once this is done, I will ship them to you, I hope you will understand, I want to be fully confident that the hotends will work for you before I ship them out, I am sorry for the delay Nate.

Hey Jeff,
No problem at all.:cool: I'm gone away every week from now to Christmas.  You got all the time you need.:D  I'm going to do as much as I can on weekends, but I don't really think I'm going to get much done on the new printer till the last week of the year.

I see what  ya mean about drilling out the entrance.  What is the advantage of the PTFE over PEEK?   Do you think any changes in dimensions are needed if 1.75 mm filament is used in the future?

Ya Nate, I just ordered 3' of 3/8" diameter ptfe from small parts.com :), when I receive it, I will be making you an insert for both sizes of filament, all you would have to do would be to change out the inserted ptfe to the size of filament you want to use :D. Also, the ptfe has a kind of lubricating quality about it, things do not bond to it easily, like filament, so, this being the case, I think the filament will not get stuck to it like it does to the peek [the problem I have been having] :cool:. I just drilled the holes in the extruder nozzles by hand :huh:, orifices are .34 mm, # 80 drill bit, they came out good, I can hardly blow though them, they should work well for fine resolution :cool:. The barrels, I machined in such a way so as to seal them selves inside the extruder nozzles when I screwed them in, this worked as well, they do hold pressure, so as not to leak filament between the threads :cool:, the peek holds the same pressure, this is important when extruding plastic correctly. The hotend elements are then screwed onto the barrels with heat sink paste on the treads and between the extruder nozzles and the elements, there should not be any concerns of a cold nozzle. I think you will have some good hotends when all is said and done, at least I hope so.:P:D:cool:

Sounds excellent Jeff.:D  I like the idea of the easy swap filament sizes.:cool:  When I created the STL for the Gregs hinged extruder there was a setting for filament size,  but I don't think using a 3mm one for 1.75 should hurt if the hobbed bolt works.  I think your hot ends are going to print some really cool parts some day.;)

I started converting some of my gray matter archives into Sketchup files today. :D I have the Y axis drive train designed and going to try printing it tomorrow.:cool:

Nate

 Nate are you home, I was hoping you could tell me at what speed you are extruding at in printrun, thanks, hope all is well.:D