Originally shared by René Jurack
Shopping at ALDI got me a thing for tinkering with my 3D-Printers 
250°C safe, “guaranteed no stickiness” and “uncutable”. I did try the last immediatly, and sure could cut it 
Now I know, where E3D got their material choice from. It feels like exactly the same silicone. (I still don’t like the E3D covers)
Hi René,
if you don’t like the E3D covers, maybe you will like mine! I made my own moulds on a CNC machine. The silicone covers I made look quite good:
http://forums.reprap.org/read.php?252,584458,709778#msg-709778
(scroll down to my second post for a picture of the fully assembled silicone cover)
http://forums.reprap.org/read.php?252,584458,709778#msg-709778
@Folke_Schwinning I know about your metal mold. I am at home in this forum 
Now it is just the question: how much for a custom one for me? 
In my opinion the e3d silicon covers are much to close on the tip. Probably the number one reason for them popping off.
Like Folke I just wrap up the block to retain most of the heat and leave the nozzle exposed. The amount of temperature drop on the nozzle will be minimal compared to a fan blowing in the whole heater block.
And anyone that sells anything as un-cutable or indestructible does not understand the capacity for humans to destroy things 
@Pieter_Koorts hehe, I always say if you make something idiot proof someone will make a better idiot.
@Rene_Jurack Sadly, I do not own a CNC mill and don’t have access to these machines anymore. 
However I can make as many silicone covers for the E3D-v6.0 as I like. If you still have a v6.0, I can make and send you some covers.
Has anyone tried adding glass micro-spheres added to the silicone to make it a better insulator?
@Daniel_Kruger Do you need more insulation?
How it’s so wonderful here
@Taylor_Landry I doubt it would hurt.
@Michael_Scholtz I have used SmoothOn materials and they work well.
I wonder if something like this on the backside of the bed heater would help on getting up to and maintaining bed temp?
It could as well as any thermal insulation
I’ve used smooth-on to make chocolate molds. It flows like honey.
If you don’t need your extruder cover to be pretty, what I would do is a tube of high temperature silicone caulking (temperature range varies, http://www.canadiantire.ca/en/pdp/imperial-high-temperature-silicone-red-304-ml-0642712p.html), print out a a model of my extruder, and smear on the caulking onto the model to harden. Caulking is much cheaper than smooth-on. You may need some release agent to get it off, I haven’t tried caulking on pla yet.
@Scott_Calkins I did it like this: http://well-engineered.net/index.php/en/29-heated-printbed-of-the-dice-sealed and it works really well. But it was primarily to insulate the 230V-AC, not the temp.
This stuff works great.
