Fixing/minimizing cracks in clear parts?

[cayman shen]

I have a GI Joe action fogure visor from 1982...think of it as a clear canopy to a model, basically. It has a crack, almost like a stress crack, I guess, as it doesn't go all the way through. Is there any treatment, coating, technique, magic powder I can use to fix it? In desperate straights, is there any good, clear resin I could cast it in without it costing a fortune? The piece is a curved band with a slight ridge on top to make it stop on the lip of the helmet, and two bumps on the side to make it fit onto holes on the helmet. Would a simple silicone mold be flexible enough for me to just pop such a part out of? Where would I get such supplies? Any good samaritan want to help me cast a smll part?

Help!

 

[division 6]

What about dipping it in Future.
most modelers do that to model canopies.

D6

 

[cayman shen]

I know that would clear and shine it up nicely, but does it minimize the appearance of the crack? I'd try sanding/polishing it first, but the crack goes all the way through, even though it hasn't actually seperated the plastic.

 

[Gigatron]

Try the Future. Worse case scenario, it doesn't work, so you soak the piece in some Windex with ammonia and you're back at square one.

You might try some watch crystal cement. Dries clear and rock hard http://www.micromark.com/WATCH-CRYSTAL-CEMENT-TWO-1and3-OZ-TUBES,7468.html

The problem with a crack in clear plastic is that there's almost always going to be a noticeable line where the crack was, causing diffraction and making it noticable.

If you go with the crystal cement, try sqeezing the part together as it dries. Maybe if you can force all the air out, the glue will fill the entire crack and make it seamless.

-Fred

 

[PHArchivist]

Future is your friend...

 

[Peter P.]

Put clear epoxy on it and let it dry in a Vacuum , this will eliminate the trapped air in the crack.I ve tried it and it works perfect!

 

[tgreco]

does Future work if you get ProWeld on clear parts?

 

[Gigatron]

does Future work if you get ProWeld on clear parts?

You'll have to use some Novus plastic polish to remove the initial blemish, but then you can use Future to fill the micro scratches and restore the clarity and shine.

-Fred

 

[tgreco]

sweet

thanks Gig

 

[knightoftheroc]

Put clear epoxy on it and let it dry in a Vacuum , this will eliminate the trapped air in the crack.I ve tried it and it works perfect!

I'd be interested in how you are doing the vacuum thing. I have a ton of equipment from my AC business, including a vacuum pump, and I converted a pressure cooker to serve as a vacuum-able vessel for an experiment once, but I doubt most folks have access to this equipment- I only have it because of being 'in the business'.

I'm sure if you have a "home made" solution others could copy, it would be helpful info, and by "home made", I'm not in any way shooting down whatever you used, only differentiating between made-at-home, versus store-bought.

 

[Peter P.]

Well im "in the business" too
thats why i have access to all this nice little gadgets...
we have a professional glass vacuum dome (not home built),sorry!
If i had build one i would share my info for sure!