Wednesday, February 07, 2007
Concrete as replacement for PTFE insulator in MK2 extruder?
Considering the amount of nichrome wire I've got, and the fact that I want to extrude teflon/etc, I'm hoping to do some testing with that stuff... Once I get some circuitry working in that department, I might get the chance to go with him to the lab at his company and mess around with some stuff...
The only issue I recall reading about with using it on the extruder head was that it was so heavy and had so much inertia... Given my design, the extruder head is fixed and the platform moves below it, that's not an issue...
For thermal insulation I will try casting conrete in the next days. For electrical insulation, which has na to be stiff I thought about wrapped around glass fibre (silk) or better a silicone tube to put under the nicrome wire.
I haven't noticed any damage to the concrete or the board it is bolted onto, but I've only gotten the chance to fire the heater up for a few hours.
Mix vermiculite in to reduce mass and increase insulating properties.
Put silicone aquarium tubing up the middle so plastic doesn't rub on/melt into the concrete.
Has anyone looked into firebrick repair? I'm thinking someone might have a little kit that would be perfect for a reprapper. ;) So far I've found this:
Seems like a few of these products are worth investigating more.
There is a 1200°F paint in there, could it be better than the stuff Forrest has had problems with?
BTW They also have vermiculite, but no price... I've looked for this before, but only found bigger bags.
Links to this post: