need help casting a windshield post

[route66modeler]

Hi, has anyone posted a how to cast a resin repo windshiled post? Thanks for any help. Steve

[Ace-Garageguy]

Do you have a broken post on a resin model? Is a post missing? I have some shots of doing custom posts in conjunction with a radical top-chop, if that would be any help.

[Mike Kucaba]

Long ago in SAE there was an article detailing that.

[davysmodels]

Steve,

cheap and easy - buy some silly putty - make a small cardboard box (3" x 3" x 1/2"). Place the silly puty in the mold box and level smooth. Gently press the original part into the silly putty. Gently remove. Pour in the resin, epoxy (or whatever you are using for the casting material). Allow to cure. Remove the part. Make a few copies. Trim and replace the damaged part. Post pics of your results.

Also - Scale Auto # 89 - Feb - 1994 - page 54 - Promo Rescue - repairs.

If you do not have this mag, I can post pics of the pages.

[Ace-Garageguy]

Only problem with some techniques is that windshield posts are mirror images of each other, so just making a mold of one side and flipping it over doesn't actually work if the post has any curvature.

Also, some materials have very little strength, surely not as much as virgin styrene, and your replacement post will be extremely fragile.

I built these windshield posts from strip styrene, filed to shape. After the liquid cement had dried fully, I roughed up the inside of the ends at the joints and reinforced them with epoxy thickened with milled cotton fiber. Very strong and withstood sanding and polishing of the completed model, as well as repeated assembly / disassembly cycles. Also tough enough that I was able to fit the windshield flush, so it snaps into place.

You could do exactly the same thing on a resin model that's missing a post, but secure the ends with Super Glue Gel instead of the styrene cement. Epoxy-reinforce the joints after the CA is fully dry. Further detail like drip-rails or windshield reveal moldings can be added with very fine strip styrene.

Edited July 30, 2012 by Ace-Garageguy

[route66modeler]

wow guys, thanks for the super info. I do have an old promo I am going to cast off of. Steve

[Gluhead]

x3 on making them out of strip styrene. Plastic is nice and easy to shape, and welding plastic to plastic is usually stronger than the alternatives, without the need to add as much bulk for reinforcement. Besides, it's just good clean building and great practice for making other parts. Go for it!