Rubber (or something like it) wheels

smeagol the vile wrote:

...Im looking at the wheels for the kit, there not plastic...

If the wheels are not plastic, what are they?  Knowing what they are made of will determine what to paint them with.

Steve--IMPORTANT!!!

If you mount the rubber or vinyl wheels onto theirplastic rims, I think you have to paint the rims INSIDE, where the rubber/vinyl will be touching them. There's some weird chemical reaction that can take place over the years with the styrene/runner/vinyl that will eventually literally melt the tires! 

I read about it on this forum, I believe, or another one that I can't remember exactly whwere?

the doog wrote:

Steve--IMPORTANT!!! If you mount the rubber or vinyl wheels onto theirplastic rims, I think you have to paint the rims INSIDE, where the rubber/vinyl will be touching them. There's some weird chemical reaction that can take place over the years with the styrene/runner/vinyl that will eventually literally melt the tires!  I read about it on this forum, I believe, or another one that I can't remember exactly whwere?

Really ? I would think that the paint would cause the reaction for meltdown. I know that if you attempt to paint red lines, sidewalls or raised lettering directly on the tire with enamel paint the stuff will stay tacky for the rest of your life.

I have some really old globby brush enamel (1970's vintage)  painted wheels, and unpainted with tires mounted in the junk box,(most glued with Testors Tube glue)  nothing going into Nuclear Meltdown yet. I wonder if the "rubber" compound has been changed in the last 10 yrs or so ? 

the spinny thing that makes it go is the engine

sorry il get me coat

smeagol the vile wrote:

So you mean paint the inside of the tire, or paint the ENTIRE wheel?

Paint the plastic parts that will be IN CONTACT WITH the rubber/vinyl part of the tire!

Just to be safe.....

Most "rubber" tires are actually some sort of vinyl, and all vinyl compounds contain copolymers (the chemical compound that that give the vinyl flexibility).  If the vinyl is placed in contact with polystyrene, some types of copolymers can migrate, causing degredation of the styrene.  The worst offender in recent memory was the flexible tires in the AMT F7F Tigercat kit.  Fortunately, few model car kits are blessed (or cursed) with these types of vinyl products.  I have built-up kits nearing 50 years old that do not exhibit melted wheels, while a fairly recent kit (Monogram Gambler dirt-track car, unbuilt) has a huge honking tire burn affecting several of the parts.  Real rubber and synthetic rubber tires deteriorate, but do not seriously affect the plastic.

If the part has a pungent "vinyl wading pool" smell, or if it feels slightly sticky to the touch, its probably of the styrene-devouring variety, and should be replaced.  As insurance, I've started dipping the tires in Future (now called Pledge with Future Shine, BTW).  Future was originally made for vinyl flooring, and coats vinyl tires quite nicely.  Future also takes paint a lot better than the raw vinyl, although I still can't recommend excessive flexing.

If you want to be obscessive, (say, a unique tire type/size/style for which there is no replacement) plate any areas of the wheel that may contact vinyl with Bare Metal Foil, which will form an effective barrier to copolymer migration.

Just my .02€

Phil

Silverback wrote:

Most "rubber" tires are actually some sort of vinyl, and all vinyl compounds contain copolymers (the chemical compound that that give the vinyl flexibility).  If the vinyl is placed in contact with polystyrene, some types of copolymers can migrate, causing degredation of the styrene.  The worst offender in recent memory was the flexible tires in the AMT F7F Tigercat kit.  Fortunately, few model car kits are blessed (or cursed) with these types of vinyl products.  I have built-up kits nearing 50 years old that do not exhibit melted wheels, while a fairly recent kit (Monogram Gambler dirt-track car, unbuilt) has a huge honking tire burn affecting several of the parts.  Real rubber and synthetic rubber tires deteriorate, but do not seriously affect the plastic. If the part has a pungent "vinyl wading pool" smell, or if it feels slightly sticky to the touch, its probably of the styrene-devouring variety, and should be replaced.  As insurance, I've started dipping the tires in Future (now called Pledge with Future Shine, BTW).  Future was originally made for vinyl flooring, and coats vinyl tires quite nicely.  Future also takes paint a lot better than the raw vinyl, although I still can't recommend excessive flexing. If you want to be obscessive, (say, a unique tire type/size/style for which there is no replacement) plate any areas of the wheel that may contact vinyl with Bare Metal Foil, which will form an effective barrier to copolymer migration.   Just my .02€ Phil

That was exactly what I was talking about!!! (But didn't know the specifics!)

smeagol the vile wrote:

so wrap some tinfoil around the wheel and put the tire over it and it will be fine?

Bare Metal Foil is ultra thin foil with an adhesive backing. It is used for like covering the trim down the center of the hood or down the side of car and ect. You can find it at most hobby shops.  Next time your out and about buy an Issue of Scale Auto just for something different, and check out all the wonderful stuff out there for autos.