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Dirty Nose!

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DynaSoar

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Here's a tip I've seen a couple times in less than obvious places. I think it should be in every kit that uses plastic or composite parts.

These parts can have stuff on them to help them break free of the mold. I'm betting that if they're machine manufactured they could also have some oil reside on them

WASH these parts with soap and water first. Sanding is good, but only if you get it all. You might not. If you wash them first, you definitely will. Your sanding may even be reduced. I think I now know why a couple nose cones I've painted the same way as all the others just refuse to take the paint well.
 

rstaff3

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I've seen this recommended fot the larger cones (AT, LOC, etc), but never on smaller ones. I should add this to the thread about your personal boo-boos. I often forget to do this.

Good reminder!
 

powderburner

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As a long-time builder of static-display plastic kits, I assumed everyone already knew this. It is certainly true that molded plastic parts need to be washed (or rinsed or soaked) in warm soapy water. Even a 13mm plastic nose cone.

This also applies to resin parts, fiberglass parts, and any component that comes from a mold where a release agent is used. And it's not a bad idea to use a damp paper towel for a quick wipe-down of cardboard BT materials and even balsa sheet fin stock to remove dust and other debris.
 

wwattles

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Does a standard tack-cloth (for dust removal) work, or does it have to be soapy water (for dissolving purposes)?

WW
 

Mad Rocketeer

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What's best to use for this? when you say "soapy", do you mean actual soap? soap can leave a film behind. (Remember the old Zest commercials?) :) I'd think Dawn diswashing liquid would be good. It's a heck of a grease-cutter anyway. How about alcohol? Would this clean the plastic or dissolve/weaken the plastic itself?
 

powderburner

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For plastic model kits, I used to use a flat tray (my Mom's tupperware always came in handy, and wouldn't get contaminated or anything) and a couple drops of liquid dishwashing soap, then filled with warm water. I would put the parts trees in one at a time and give each face of the tree a gentle scrubbing with an old toothbrush. After washing all the individual parts trees, I would puzzle/stack them all back into the tray and let it sit for an hour before rinsing them off.

It's just a sort of habit that I got into, I really don't know how necessary it is to do this. Some of my friends never did this initial cleaning and did not seem to have problems with their kits. Who knows? It's easier to go ahead and do it (I'm talking five minutes' worth of work) and not worry about it again, IMHO.

I don't think you should use alcohol.
 

DynaSoar

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Originally posted by wwattles
Does a standard tack-cloth (for dust removal) work, or does it have to be soapy water (for dissolving purposes)?

WW
If it's oily or waxy, a cloth will spread it but a detergent would dissolve it.

I plan on using a bowl of water with a few drops of Dawn and a plastic dish scrubber. "Rinse And Repeat!"
 

not a lib

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I use rubbing alcohol-70%, for all plastic cones. It cleans the cone so the paint holds good. It never fails! The paint holds. Been doing it for years!
not a lib:cool:
 

Mad Rocketeer

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I usually buy the 91% alcohol we can get here. Our grocery store chain (H.E.B.) carries 50%, 70-something%, and 91%. I may avoid using alcohol for pastic cleaning altogether, but if I do use it, I'll probably at least dilute it some. Could just pour some in the Dawn-water mix, but that would probably dilute it to uselessness.
 
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