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Cementing problems

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#1 Psychographic


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Posted 27 October 2012 - 10:32 AM

I have two specific problems with cementing parts that I hope I can get help with.

I normally use straight MEK for cementing. I also have Plastruct Bondene for things I need to set faster, both have the same problems.

I have no luck cementing Plastuct Styrene, it might hold but there is no strength whatsoever. and usually it winds up breaking off. I have even sanded it first in case there was a release agent or something preventing the bond.

My second problem is with small diameter rod and half round from Evergreen. This problem is when I try to cement a tight curve the styrene will just snap when the cement is applied.

Any suggestions on either problem?

#2 martinfan5


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Posted 27 October 2012 - 11:22 AM

I use testors tube glue for evergreen and dont have problems, maybe try that and see if it helps

#3 Kris Morgan

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Posted 27 October 2012 - 11:23 AM

Try using a little less glue. Sounds as if you may be using too much? This will cause the plastic to become too soft.

#4 Ace-Garageguy


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Posted 27 October 2012 - 11:34 AM

Some Plastruct products are butyrate plastic rather than styrene, and solvent-type adhesives don't work very well on them. The only reason I noticed was when I had problems similar to yours. As far as I recall, I've not had problems with the solvents you mentioned with straight styrene.

#5 TooOld


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Posted 27 October 2012 - 11:52 AM

You aren't the only one with these problems . Particularly with the Plastruct items . The shapes that I've bought are a dark grey color ( ABS ) and nothing seems to work . Plastruct sells "Plastic Weld" which is suppossed to bond ABS to Styrene to butyrate plastics . I've never bought it because I figured I didn't need another cement sitting around . maybe it is the answer . Lately I avoid buying anythng that isn't styrene .
As for the small styrene rod snapping when MEK is applied , it is very frustrating . I've started to use small dabs of super glue to locate the rod in position , then go back afterwards with the MEK to permanently bond it in place . This seems to solve the problem , maybe since the rod is already stressed and set in place before it is applied .
I hope this helps .

Edited by TooOld, 27 October 2012 - 12:02 PM.

#6 slusher


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Posted 30 October 2012 - 04:18 AM

I use Testors glue in the orange tube for everything l do works excellent...

#7 Jantrix


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Posted 30 October 2012 - 05:50 AM

I use testors tube glue for evergreen and dont have problems, maybe try that and see if it helps

I use Testors glue in the orange tube for everything l do works excellent...

*shudders* Oh man that's nasty stuff. Switch to a Zap-a-Gap type CA glue and you will never look back.

The Plastic Weld from Plastruct does work well with Plastruct products but it does take time. I think Bob has the right of it though. Tack it front, rear and in a curve with CA glue and use the solvent for the rest.