Molding help

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#1

I am having trouble understanding the molding process for an object that has a flat side, and a not so flat side. Take for example an object I am attempting to mold, a fuse box cover for a toyota celica. This is a small rectangular object. The top side is rather flat, but the back side has a rectangular shaped seal and 2 raised areas bout 1/2 inch deep that serve as guides for mounting the cover. These guides fit into slots already on the car engine. My question is how to mold the backside of this object? I have sucessfully molded the top side of the fuse box using a plaster type material.

Even if I was able to mold the back side of the fuse box with a type of RSV silicon rubber or somthing of that sort, how would you create the carbon fiber part of that uneven surface, while having a top side that is flat? Even if I made 2 seperate parts, one of the top side and one of the back, and tried to bond them togather, there would be a gap in the space between the flat side and the raised guides on the back side.

Has anyone been able to create a part similar to this? Any help/ideas would be great.

#2

Can you post a picture of what you’re talking about?

#3

I was able to mold it with RSV rubber, which is really expensive stuff. I will get you the Pictures by this weekend. I want to try and make a mold of the plastic part out of fiberglass. Is this possible? How do you keep the fiberglass/resin from bonding to the plastic? Thanks.

#4

epoxy and plastic doesnt bond well because the epoxy will shrink breaking the initial bond between the two. why dont you make a cover that can be placed over the top of thebox. then just glue it down. then you could make covers for coolant resivior and fuses ect.

#5

resin will not bond to the plastic. So if you’re molding off of a plastic part, all you need is some mold release wax.

#6

Thanks evan I am going to give that a shot.

Dallas: We could do that very easly, the only problem is I think people want the real thing. This is a product we are trying to manufacture and sell. Would you purchase just a cover? Or would you want to replace the whole piece?

#7

well yes i would buy a cover. thats made of the real thing. still looks good too.