Part stuck in the mold for the first time in 3 years :(

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#1

Well we are making a prototype dodge charger hood for the Dodge Factory D1 Drift car and the skin stuck in the mold. This is the first time a part has stuck in the mold on me. My question is, do you repair parts like this and if so what is your best method? I can easily repair air pockets in parts but never attempted a repair like this. I guess I can always make another one but would love to repair this one. This is right out of the mold. The mold was not really buffed that much because these hood will be mostly painted. Damn these hoods are huge!! tring to us a 50 inch fabric on a 54 inch hood kinda sucks.

You can see where it stuck

#2

If you say that the hood is going to be painted anyway, that would seem to make your life a hell of a lot easier. Just fix it like any ordinary fiber glass repair. Now, if it is only a partial paint and the cosmetics for this section still matter, you would have to weigh the material cost verses repair time. It might turn out that it takes longer to repair this hood than make another, but the material costs will obviously be higher to make a new hood. To repair it, I would just treat it like a mini overlay and build the surface back up to match the surrounding area. The problem with this method I have found is that you have to pay particular attention to removing any surface distortions for that smooth, seamless surface. Tell us how it comes out.

Another thing I remember with the 50’ fabric on larger hoods is to create a centerline on the hood and split the surface layer into two separate pieces creating a “V” weave pattern where they join in the middle. Hood strength would come from subsequent layers and the subframe if you are using one.

#3

For the record, what mould release did you use?

#4

I was using TR high heat popping wax. Like I said this is the first time I have ever had a part stick and would suggest this wax to anyone. I used PVA for a couple months but went back to wax

#5

Have you tried any of the semi pernament releases?

#6

yeah I have used several, but just rather use the wax because I normally never have a problem with it, just my luck it stuck on an expensive part!

#7

In some cases, I prefer to use a mix of semi perm and wax. Use a semi perm mold sealer and then a couple coats of wax. I found that the semi perm release that goes on after the sealer can be too slippery and the wax gives good traction on vert surfaces for the gel coat to cling. But, the flat stuff, the semi perm is smooth sailing, never any problems.

#8

Kyankton,
Are you saying you use the cleaner, sealer and not the release from a semipermanent mold release system and then you use paste wax over the sealer?
it sounds like a good idea.

#9

I am going to have to give that a try

#10

That exactly it! First use the cleaner, then the sealer. I hate using just wax because of the number of applications required, but I like the “grip” the wax gives to whatever resin you are putting down. Don’t go trying this on a large mold and blame me if you ruin it. First, try is on a small sample piece and see how it works for you. Now, that being said, I don’t do this all the time and sometimes I prefer to use the semi perm release instead on flatter surfaces because of the low surface tension. I think that Evan use to sell just the sealer as a semi perm release. Technically, you should use something else over the sealer to assist in the release.