The main issue is the heat of the engine bay. We have tried filaments that can be done with a Bambu printer that has the highest temp ratings and they do not survive. Up to about 230 degrees all is ok, but once you exceed 250 then they start deforming. I doubt TPU will be ok. Believe me if you saw the number of test pieces on my desk you will think I am terminal cover obsessed.
From some testing we have done, black car, heat soaked engine bay, AZ mid summer we would like to be able to handle about 280 degrees.
The issue is most extrusion machines melt the filament to print the part, but now we don't want it to melt again. Once you move away from extrusion the price jumps.
If someone in AZ or some other hot place has a need for some, I am prepared to print a set and send them out for real world testing. Just shoot me an email at
christo@sleeoffroad.com.
We even went so far as to make a change to the newest terminals to better accept the covers as designed but they will still retrofit to the old terminals.