What Material to Use As "Buck" for Vacuum Forming?

[hooknladderno1]

Hi Gang,

I want to try to replicate the "lightbar" below via vacuum forming. Having searched, there are several posts and articles on the vacuum forming process, but not much on making the "buck". What do you folks use to build your original when making custom parts to vacuum form?

I appreciate any and all suggestions. Thank you!

David

[krow113]

One answer would be: "Whatever works"

Here I used a Christmas ornament piece to cast a master or buck (which may be the wrong word for what we are discussing) then vac'ed it .I had to keep raising the master until the wrinkles came out:

For a 1/8 scale S&S carburetor velocity stack:

My advice would be to use the existing light bar to make a mold , then cast a master and vac that.You may even be able to suspend the model over the silicone to get the mold.

Thank you ,Steve

Edited November 28, 2013 by krow113

[DrGlueblob]

Clever idea, Steve. I use basswood or tupelo for medium to large bucks. Both woods shape easily. I've also tried plaster bucks from a latex mold with mixed results.