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Old 11-16-2021, 01:17 AM
olDave olDave is offline
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Join Date: Sep 2015
Posts: 152
Default Has anyone worked with cast resin models?

(I am not sure at all as to what area these questions should be posted)

If you have built anything from a cast resin kit, I need your help.

I was recently handed a bag of broken parts from a sculpture that had been dropped and damaged, and was asked if I could fix it. Peering through the broken places at the innards, the sculpture sure does look like it was poured into a set of molds, just like you make resin castings. It has thin spots, thick spots, weird finishes on some areas (bubbles?), full-depth color in the material, and the "feel" and "smell" of cast resin. So----

What adhesives can be used? I am thinking that CA should do a good job but would like to know if there are any other, more specialized adhesives recommended.

For the places where all the broken bits were not recovered, and I have gaps to fill, can I use a product like Squadron putty? Or is there something else I should start with?

If I have to do any touch-up painting, can I use something like those little bottles of Testor's paints? (these paints are sold for use on styrene plastic model kits)
I am hoping that Testor's stuff will be chemically compatible with the resin, and won't melt it or anything horrible like that.

Any help would be appreciated

-Dave
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  #2  
Old 11-16-2021, 01:23 AM
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ghrocketman ghrocketman is offline
President, MAYHEM AGITATORS, Inc.
 
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Location: Nunya Bizznuss, Michigan
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A buddy of mine has extensive experience with plastic models including resin.
He told me all 3 liquid plastic cements from Tamiya work.
The Orange-cap regular, the Dark green cap Ultra Thin, and Light green cap Fast-Drying Ultra Thin.
Try those. Any good hobby shop will have at least 2 out of 3.

I keep all three on hand, along with Tenax 7R, Micro Mark "Same Stuff", Plastruct Bondene, Plastruct Plastic Welder, and "old school" Testors Liquid Plastic Cement (which is a 50/50 mix of MIBK and MEK).
I also keep vintage tube-type Pactra plastic cement on hand.
I'm well situated to bond all plastics.
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Old 11-16-2021, 07:41 AM
frognbuff frognbuff is offline
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Join Date: Oct 2012
Location: Colorado Springs, CO
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I have built many resin models.

Yes, CA is the only glue you can use. I use CA, plus CA accelerator, to fill air bubbles. You have to sand IMMEDIATELY, or the CA will become harder than the surrounding resin and will be nearly impossible to sand without damaging the surrounding area.

As for painting, I clean resin thoroughly with soapy water before painting. Then I use my usual paints - Krylon primer, Rustoleum, Testors, etc. Just follow the normal "rules" for mixing and matching paints (to avoid "raisin skin" effect).
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Old 11-16-2021, 10:18 AM
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ghrocketman ghrocketman is offline
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What TYPE of resin are we talking about here ?
I like using CA in about one area alone: constructing WOOD R/C aircraft, where the glue penetrates into the grain.
I hate using it on any plastic unless absolutely necessary. It creates a mechanical bond only, unlike plastic welders.
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  #5  
Old 11-16-2021, 08:32 PM
frognbuff frognbuff is offline
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I honestly don't know the resin type - just that all resin models I've ever made seem to be the same type of resin!

Here's a tutorial link from a manufacturer of resin models:

http://www.realspacemodels.com/building-tips

I'm sure one could email them and find out the resin type as well.
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  #6  
Old 11-16-2021, 10:45 PM
olDave olDave is offline
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Join Date: Sep 2015
Posts: 152
Default Thanks guys

I am going to get some fresh supplies (mostly because my old CA is so old that I don't know where it is anymore) and give it a shot. I am planning to dry-fit the pieces and swab some thick CA on the inside of the joints. I am only going to attempt paint repairs if I finish reassembing all the bits and pieces and find that there are missing areas that have to be puttied and reconstructed.

For a finishing touch, I have a bottle of micro-balloons that I can smooth into any surface cracks or pits, and then fix in place with a bit of CA.

And I never actually volunteered for this, I just stood still a moment too long when they came looking for someone to help.
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Old 11-17-2021, 09:02 PM
frognbuff frognbuff is offline
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Hopefully you're working on a quality model. I've built resin models where the quality easily rivaled styrene kits (Pit-Road Models in Japan is a great example). I've made others that were so crude and awful that I actually gave up.

A fantastic maker of resin SLV models is New Ware Space Models in the Czech Republic. I have purchased their models many times and have never had any issues or disappointment.

https://mek.kosmo.cz/newware/index.htm

A nod to our neighbors to the north in the form of Canada's Belcher Bits models:

http://belcherbits.com/

And of course our own RealSpace models: http://www.realspacemodels.com/

Rocket models are rarely popular enough to warrant the cost of making injection molds, so "resin is the rule" for most subjects!
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