Help removing plug from mold!

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#1

Ok so I made a two pay mold of an auto body panel. The top released fine as it was a normal metal body panel. The bottom however did not release. The backside is metal coated with a very hard paint type coating. I used two thick coats of pva, but that’s it. I already know I should have used wax, or just a better release agent completely. In any event, now I have a plug stuck in the mold.

I’m going to try soaking it in hot water tonight, and I was going to try heating the back with a heat gun as well. Any other ideas? Worse case would be to cut the mold off of my plug, but that would obviously ruin all of my hard work. The pva didn’t do a great job, but I don’t believe the tooling gel made a solid bond to my plug either. So I think it will come off with enough work.

Any ideas or advice from any of you more experienced guys?

#2

Water. and patience. Quite sticky, so apply some force, and add some patience :wink: Good luck.

#3

A thoroughly waxed part covered with PVA will release fairly easily. Since you used PVA only, water would be the best solution since it is water soluble. If you do a second run, wax the master plug multiple times followed by spraying PVA with a HVLP gun. Ensure that you use a wax that is compatible with PVA, or you can get some fish-eyes in the PVA. As susho mentioned, water-patience, in that order.

#4

Yea I figured water may be the answer…if I let it sit in my bathtub for an hour or so on each side, I’m hoping that does the trick. We’ll see what happens tonight…

#5

High pressure washer works a treat. Have done a few demouldings at my local car wash :wink:

#6

haha, thats funny and then I read who wrote it and it made it even funnier

#7

I think its safe to say everyone ends up hitting a stuck mould with a hose every now and then. sometimes it doesn’t matter how clever you think you are, xxxx just binds up. take it slow and have a laugh while you do it.

#8

And when in doubt, a 100psi blast from a tyre bead seater will sort out even the most stubborn of mould sticks :wink:

https://youtu.be/aLBRMpyU_Z0

Free tip for those playing at home: cover your ears and hold on REAL tight!