Assembling painted parts

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ActingLikeAKid

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So GENERALLY, I know that the wisdom is that painted parts don't go together well.

But I'm putting together one of these...

If you can't see (it's not really clear in the pic) there's a ring fin that slots into the main fins. There's no way I could mask things well enough at the bottom to make it work. Right now my plan is to paint everything (I can avoid painting the fin roots, at least!) then assemble everything with epoxy, maybe using a hacksaw blade to try to remove a bit of the paint where the fins will go. Using 5min epoxy because I think white glue would be useless on paint to paint, epoxy might have a better chance. The good news is that the design is structurally sound without glue - the ring fin holds the fins in place against the body. So the glue is mostly just to stop things from wobbling around. Heck, I could probably even use CA if I felt like living dangerously....

Thoughts? Suggestions?
 
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Zeus-cat

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I think carefully filing off the paint would work. Or, you could cut thin strips of masking tape and apply it to the ring before painting and then pull it off before applying epoxy.
 

ActingLikeAKid

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I think carefully filing off the paint would work. Or, you could cut thin strips of masking tape and apply it to the ring before painting and then pull it off before applying epoxy.
Thought about the masking tape idea ... that seems like a ton of really high-precision cutting and placement. (and at least with the filing, it would be assembled first)
 

SCIGS30

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I notice the directions do recommend painting before adding the ring to the slots. Also I don't think you need much glue on the ring, just make sure to glue the fins down and add the required fillets. For glue I would just use plain white glue or if you want a thin whicking PVA glue, try Deluxe Materials Rocket Card Glue. It is a super thin PVA glue that works almost like CA......I said almost. You could also use CA glue, but I would be afraid of making a mess, with PVA glue you can wash it with water from the painted surfaces. I really don't think it will take much glue for an adequate joint. The best thing would be to mask the ring where it will make contact with the fins then paint. Also you will have to jam or mask something in the fin slots as to not get paint in there, that is the correct way. Now if it were me, I would first paint the ring the color I want. Then I would test fit in the slots on the fins before painting the fins. I would not even mess with masking the area where the fin contacts the ring. Since the ring is painted, I'm guessing I will have to enlarge the fin slot to accept the now slightly thicker ring. Once the ring fits, I would jam a sliver of wood into the fin slot and paint away. Once all dry, I would simply glue the painted ring in the slots with pva glue, wiping away excess glue with water.
 

ActingLikeAKid

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I notice the directions do recommend painting before adding the ring to the slots. Also I don't think you need much glue on the ring, just make sure to glue the fins down and add the required fillets. For glue I would just use plain white glue or if you want a thin whicking PVA glue, try Deluxe Materials Rocket Card Glue. It is a super thin PVA glue that works almost like CA......I said almost. You could also use CA glue, but I would be afraid of making a mess, with PVA glue you can wash it with water from the painted surfaces. I really don't think it will take much glue for an adequate joint. The best thing would be to mask the ring where it will make contact with the fins then paint. Also you will have to jam or mask something in the fin slots as to not get paint in there, that is the correct way. Now if it were me, I would first paint the ring the color I want. Then I would test fit in the slots on the fins before painting the fins. I would not even mess with masking the area where the fin contacts the ring. Since the ring is painted, I'm guessing I will have to enlarge the fin slot to accept the now slightly thicker ring. Once the ring fits, I would jam a sliver of wood into the fin slot and paint away. Once all dry, I would simply glue the painted ring in the slots with pva glue, wiping away excess glue with water.

Cool, thanks for the tips. The slots are REALLY thin; I was thinking that a couple of index cards would mask them well (and if I'm clever about it, make a nice stand for painting, too). The slots are big enough that I can get some sandpaper in them, so that if/when they don't fit after a coat of paint on the ring, I can just sand them out.

This is going to look cool when it's done, I think. My kids have demanded orange instead of purple for the NC and fins; it'll be interesting to see how that comes out.
 

neil_w

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$*@&%ing rings.

It does seem like you're in decent shape in this case you don't need so much structural support from the glue. When that's not the case (see aforementioned link) it gets painful. Any area that you mask off to keep clear for gluing will need to be hand-painted later, and getting that done cleanly can be anywhere from hard to extremely hard, depending on the paint scheme.

Good tips from SCIGS30, I'll keep those in mind for future builds.
 

caveduck

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I agree with what SCIGS30 said about not needing to mask in this case. But as far as the glue choice I'd just use a very small drop of medium CA to hold things in place. Lots of serious scale models get assembled with CA after painting. You don't get too much bond strength, but usually enough.
 
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