Insulating heatblock using Aramid cloth & kapton or silicone paste?

Having some issues with "cold extrusion prevented" / jams on PLA recently and want to try something new.

I was told wrapping heat block with aramid/Teflon cloth + kapton is a good way to insulate heat from external airflow but cloth and tape seems non user friendly / inaccurate.

Has anyone tried using silicone paste or sugru etc as a way to mould an external skin for the aluminum heat block?

Seems like it would be a tighter fit / better insulation than cloth but I haven't tried yet.
Hoping someone more experienced might help shed some light.

Edited 1 time(s). Last edit at 07/23/2016 12:27PM by CharlieK.

Forget Sugru, it is not able to withstand the temperatures you are printing at.
I use this
[b.bonkers.de]
[b.bonkers.de]

The high temperature silicone (meant for tin casting) i used holds up very well so far.
However, i don't think this will solve your original problem, it will help to maintain temperature better and to prevent injuries. Also it is easier to clean.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]

Wow.

This looks perfect..danke schön!

I've never used a cast before but looking at the pictures I think I just fill one piece of the mold with the putty then place other piece (covered with separator like Vaseline ) inside first piece and squish until cured?

Can cast be PLA or Abs?
Can't wait to try on my E3d V6lite.

Hopefully rebuilding hotend and this silicone cover will stop my hot end jamming problem.

Edited 1 time(s). Last edit at 07/23/2016 03:43PM by CharlieK.

Yes, just fill the outside part of the mold with a few gram of the liquid silicone mix (it usually comes as a two component material) and then slowly press the inner part in until it sits tight in the outer part.
I use ABS printed molds and PTFE spray as a seperating agent, vaseline should work just as well. Make sure to apply it thin though. PLA should work just as well as ABS.

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[www.bonkers.de]
[merlin-hotend.de]
[www.hackerspace-ffm.de]