Cheap B@stard Cold-end, Mark 1
This is what you get when you have a scrap pile, a lathe, and not enough sense. Naturally I’ll put a fan on it and test before putting it in service.
I fully reserve the right to come back here in a day or two, all cranky and upset, and tell y’all I ordered an e3d, but until then, I’m only out about $3 for the tap for the Hot-end.
Well done! I hope it works perfectly!
Without a heat break I think you will have trouble. But looks cool. What material?
Brass. There’ll be a fan blowing over the fins for heat rejection. I say it’s mark 1 because I already see a problem with the inner diameter. I used the J-head PEEK schematic, and it’s dimensions include space for a sleeve and PTFE tube…I’ll try to get them out of the old cold end, but if I can’t get 'em out…another hour and I’ll have Mark 2 ready for testing.
Honestly, I’d keep the PTFE sleeve if you can manage to get them retrieved from the J-head PEEK. If you can manage that, the metal heat break has a chance of working. Maybe.
There’s still some meat that could be removed, and if I made mark 2 a shade longer, I can get the hot end farther from the heat exchanger, kinda like ‘V’ on this Pic:
If I can’t salvage the PTFE from the J-head, I’ll remake the brass part with an ID that matches the PTFE I do have.
I’m curious to see how this turns out.
Good thread guys . I also hope u make it happen good job.
What is the material. Aluminium and yellow metals conduct and stainless has the lowest coeficent of thermal conductivity.
Sorry. Brass. That should work great.
@Mike_Miller that pic of v is the all metal j- head. It was predecessor to the Trinity labs metal magma. Be prepared for much trouble with pla.I use the metal magma and print only abs because I can’t print pla. I am using e3d for the new build. BTW the Trinity hot ends do well with most other plastics (probably issues with pla mixes as well i.e. lay wood or laybrick. But if you use the PTFE sleeve only abs most likely. I have done much research as I once made an all metal hot end too. Brass will have toooooooooo much heat creep. I recommend aluminum or stainless steel for the heat sink and stainless for the best break brass is awesome for the heater block and nozzle
If I was going to adapt a j-head to get rid of the PEEK, I would cut stainless into the same shape as the Mk V PEEK insulator, but with the part around the PTFE turned down to a radius about 1mm larger than the PTFE, only using a larger diameter where necessary for the groove mount on one end and the internal threads for the nozzle on the other. With slots cut in the SS the same shape as the ones in the peek, its thermal conductivity would be greatly overpowered by the effectiveness of a small fan (or possibly just the airflow from moving the extruder around).
Yeah, this is definitely an idle distraction while I come to grips with buying someone else’s R&D efforts. 
After a night’s noodleing I’m also seeing the value of the head rejecting heat in parts, but then isolating that heat with parts that don’t conduct.
Looking up thermal conductivity, (from http://www.engineeringtoolbox.com/thermal-conductivity-d_429.html), Aluminum is 205, Brass is 109, Stainless is 16, and Carbon Steel is 43. Of the four materials, guess which I don’t have?
So, in a perfect world, you’d have the brass hot end, an aluminum radiator (with I have in abundance), and a Stainless insulator.
Incidently, there’s a LOT of materials where I just flat never considered their thermal properties. Delrin/Ascetal, for example, would give it up at 175C, and Acrylic, at 160 (conductivity 0.6)…which is unfortunate, as they’re slightly easier than brass to work with.
Looks like I’ll pick up an equivalent Die to go with the TAP and making a metal sammich to experiment with.
@Whosa_whatsis There’s definitely some experimentation to be had with dimensions, on this first case, I wanted to be sure I left enough meat to work with…there’s nothing like the sinking feeling of spending an hour on a part, only to have the toolbit dig in and either bend it into uselessness, or tear it apart into uselessness.
The MakiBox hot end is just an aluminum nozzle that is heated by a flex heater and an m4 stainless barrel screwed into the aluminium. The barrel threads into an aluminium heat spreader, and the POM for the platform that is directly moved around by the guide rods stays cool enough to touch without any cooling.
