Stripping Paint Off A Very Rare Shell

[dazaa 0]

Ok so i have an almost impossible to find nichimo stratos lexan shell which has been badly painted on the outside, however the original (impossible to find) decals are still on the inside of the shell. Is there any way to strip the pain t off the outside without damaging the decals? The paint is quite thick but can be scratched off with a screwdriver so shouldnt be to hard to remove. Should i use easy off oven cleaner? Obviously cant use brake fluid as that would ruin the inside of the shell.

Regards

dazaa

[dimblum 1]

Your in troubled waters with this one. The only chemical found to strip paint from Lexan (polycarbonate) without fogging the clear finish is Nitro Fuel. Even if you use it, you will probably have to keep it submerged for a day or more (depending on how thick the paint is), so the decals are going to go - bye bye.

Chemicals like Easy Off (Lye) will wreck a polycarbonate shell by fogging the clear surface and weakening the shell. Same thing with Brake Fluid.

To my knowledge, no decent chemical has been discovered to remove paint from a clear polycarbonate shell without damaging it in one way or another

[Origineelreclamebord 45]

you could try to seal off the inside of the shell with a plastic bag and tape, silicon sealant (if that doesn't melt away in nitro fuel) or anything else you can find to seal off the inside of the shell to make it water/fuel proof

[redzone 212]

didnt willychang post a link to a site with lexan paint stripper spray a coupla weeks ago?

[WillyChang 1814]

have no evidence either way, but methink everything on that site is best bought only on 1st April

[mb_c11 0]

Depending on the type of paint, you could use pure or near pure alcohol (ethanol). Alcohol-based (duh...) paint will dissolve in it. Put the body in a tub and fill the tub with pure alcohol. After a while, carefully rub off the paint with a paper towel soaked in alcohol.

The stickers should remain unharmed, but to be safe try applying some alcohol to one first.

The body will not fog.

Just be sure to do this outside or in a well-ventilated area, otherwise you'll go drunk just from the alcohol vapors . Perhaps you should also wear gloves, as the alcohol will dry out your skin.

[siriussr@gmail.com 0]

Go to tower hobbies and search trinity body blast. Apparently it works pretty good and nobody knows about it. I haven't had a chance to use it yet though.

[Live Steam Mad 17]

I used O'Donnell glow engine racing fuel (Car, 16 per cent Nitromethane) to strip my Kyosho Optima (lexan). Got it from my local Hobby Shop, Vulcan Hobbies. Perfect results. Shell stayed utterly clear. Use washing up gloves though and eye protection, and do it outdoors like I did. Nitromethane causes cancer.

Cheers,

Alistair G.

[RETRO R/C 59]

I have stripped MANY bodies with great success with Nitro fuel. The biggest secret is to get RACING quality fuel in a highish (25 to 30 %) Nitro. The reson for this is tha the high percentage of QUALITY RACING nitro stips the paint. Lower oil content fuels are best. 8% oils are usually the norm for high end racers (pre-blended).

Just get the highest nitro , lowest oil content fuel that you can afford - it usually wipes off after a soaking - or evn just dab an area with rag with the fuel on it - sometimes it just rubs off.

Cheers

Darryn

[Live Steam Mad 17]

Exactly, good point Darryn.

"Straight" glow engine fuel has had in the past nominally 20 per cent Castor oil and 80 percent Methanol. NO NITROMETHANE!!

Therefore "straight" fuel won't be good for paint stripping! The Methanol is the actual "fuel" - note, no gasoline (petrol) is used. The oil is simply for engine lubrication.

Nitromethane makes the engine make more horse power because "the oxygen content of Nitromethane enables it to burn with much less atmospheric oxygen in comparison to hydrocarbons such as gasoline. 14.6 kg of air is required to burn one kg of gasoline, but only 1.7 kg of air for one kg of nitromethane. Since an engine's cylinder can only contain a limited amount of air on each stroke, 8.7 times more nitromethane than gasoline can be burned in one stroke".

It seems that it is the Nitromethane itself that strips the paint. (sidenote : maybe this is why the similarly named Nitromorse paint stripper works? (I never looked that one up).

Therefore the best would be as Darryn says, a "racing" type fuel, because this generally has 8 per cent Synthetic oil (you need less Synthetic oil in high performance fuel as Synthetic oil protects the engine just as well at a lower oil content than with Castor oil) so less oil content therefore more Methanol, and of course the more per cent Nitro. the better for paint stripping. Thus 30 per cent Nitro. racing fuel would in theory work best.

However Nitromethane is very expensive and can easily double the price of the fuel compared to straight fuel. That's why I bought the 16 per cent O'Donnell fuel as I simply got the lowest Nitro. fuel that my local hobby shop sold as I am a cheapskate. It still stripped paint easily on my Optima's Lexan body.

Cheers,

Alistair G.

[dazaa 0]

After all of that great info I simply rubbed the whole shell down with fine wet and dry. It lost the shiny lexan finish but didn't fog it too badly, more like scratching rather than fogging. Be warned it will make your fingers bleed, you will never get your shell back to pristine condition and you can't get in to all the corners. Im probably going to leave the shell as it is now with all the different layers of paint left in the corners and the decals and original coulors just about noticable underneath.

dazaa

[Live Steam Mad 17]

If you paint the Lexan on the outside, maybe you can add a coat of clear (gloss) to bring back the shine?

Cheers,

Alistair G.

[caddy shack 0]

I use 30% nitro never had any problems, ive even stripped pro painted body shells that have had nitro blocker used on them.

Also theres this company its local to me www.delta-ag.co.uk they do two diffrent products, one thats good for lexan & the other for abs shells, but its around 8.00 per ltr if you look in buggymunchers showroom you can see how it worked on his vintage lancia body.

.

[DavidKY502 0]

Do a search here or google maybe for repairing plastic windshields. I swore can across an article how to take the scratches out of them to where the look like new. Thoose are plastic lexans plastic figiure have to be worth a shot to try it.

[HunterZero 76]

Use some 2000+ grit wet sandpaper, then Novus #3 and #2 plastic polishes and a bit of elbow grease, and you should be able to restore the finish.

I've had great success with nitro fuel on older PC paints, but no luck trying to shift modern fuel-proof Tamiya PS paint. I've tried up to 20% fuel. Has anyone been able to shift PS paint with higher percentage nitro, or anything else? I am looking at going down the sanding route.

I did notice that if you spray more PS paint on, the thinner in it 'dissolves' previous coats so it will bond - however, I am also pretty sure that it etches the polycarbonate and would damage it if used as a stripper.

Wish they made a fuelproof polycarbonate paint system with a paint stripper specifically for that paint.

- James

[Live Steam Mad 17]

I've had great success with nitro fuel on older PC paints, but no luck trying to shift modern fuel-proof Tamiya PS paint. I've tried up to 20% fuel.

Holy cow! I'm just off to try that right now with my PS paint bought for my Frog in the last year.

Cheers,

Alistair G.

[HunterZero 76]

Holy cow! I'm just off to try that right now with my PS paint bought for my Frog in the last year.

Well - Let us know how you get on!

I did try one brand of acetone free nail polish remover on a piece of scrap. It didn't seem to fog the lexan, but was very slow going removing the PS paint, and didn't seem to remove it all. I didn't try for too long, if I'd used it for longer, it still may have fogged the lexan.

- James

[buggymuncher 1]

I think you may be OK on this one as the paint is on the outside. As Caddyshack said, the company is in warwickshire ( I think they do mail order) and the product you want is Delta Eliminator.

If you seal off the inside of the body, lay it in a tray and keep "basting" it with this stuff the paint will dissolve completely. I've used it on several shells and it works absolutely perfectly. Don't get it on the stickers though, as it will remove the colours.

Good Luck !

[Live Steam Mad 17]

Well - Let us know how you get on!

I did try one brand of acetone free nail polish remover on a piece of scrap. It didn't seem to fog the lexan, but was very slow going removing the PS paint, and didn't seem to remove it all. I didn't try for too long, if I'd used it for longer, it still may have fogged the lexan.

- James

Oh Dear

It seems that it is true. Tamiya PS paints are now impervious to Nitromethane.

I got some 3" long Lexan strip off my scrap from my Frog body (re-re I think since it had protective film on it) and pealed off the film and then sprayed it half with PS-1 White (masked off other half) and then PS-11 Pink and then left it for a whole day to harden indoors (about 17 deg. C ambient). Then tonight I went to dip it into some O'Donnell racing fuel (16 per cent Nitro.) and whereas on my 2nd hand Optima body the paint almost fell off the moment it touched the Nitro. (started to dissolve and run off straight away) at about 17 deg. C ambient (done outdoors, last summer), this time it had no effect whatsoever, though admittedly it was done at about 3 deg. C ambient in my back porch with the door wide open.

So I went to scrub it off with a smoker's toothbrush (best kind, hard bristles) and again no effect. 10 minutes of hard scrubbing and rubbing my fingers over it hard with rubber gloves on and again nothing. Not even the slightest hint of pink paint or even slightly pink liquid coming off.

Conclusion... Nitro. doesn't work on Tamiya PS paints bought a year ago.

I have left it overnight to soak in the Nitro. I'll check it again in a few days' time but I don't think there'll be much change

Any ideas on what might dissolve modern Tamiya PS paints, without fogging the Lexan? I did try White Spirit on another 2 tone Frog test spray (exact same paints) a few weeks ago and it did seem to be a very, very partial solvent for it but it was more mechanical removal than chemical I suspect and only a tiny patch was tested.

Cheers,

Alistair G.

[Live Steam Mad 17]

Test now complete. It's 6 days later and the **** 16 per cent O'Donnell fuel hasn't had the slightest effect on Tamiya TS1 White or TS11 Pink on my test piece. I took it out of the Nitro' bath and scrubbed it and there was not the slightest hint of pink paint coming off. In addition the Nitro' fuel had even greatly softened the Lexan and it was now very flexible and had lost it's rigidity

So that's settled, there's no way to strip this paint off with this method. I wish someone knew of a solvent for this paint.

Cheers,

Alistair G.

[HunterZero 76]

Short of finding a brand of acetone free nail varnish remover that works without fogging the lexan, I think we're SOL.

Although I did find that spraying more PS paint will attack the existing PS paint sprayed down. However I am also sure that the thinner used in the PS paint doubles as an 'etch' agent for the paint, and will attack lexan.

Otherwise, it's sandpaper time.

- James

[Live Steam Mad 17]

To continue with my test piece ( polycarbonate from Frog ) the PS paint is not showing the slightest sign of dissolving in Methylated Spirit ( Meths ) either

I would try with Tamiya Lacquer Thinner but I've run out and I'm trying to obtain a fresh supply. If and when I receive this I'll try it on this test piece.

Cheers,

Alistair G.

[HunterZero 76]

How about mineral spirits or turpentine?

- James

[TamTom 367]

I always use Tiger Entfetter (Tiger degreaser) which is sold here in Austria. It is water based and do not harm to any plastics at all. Only aluminum, copper and brass do not like the Tiger degrease. You can even have your lexan body in there without the decals beeing off after the bath. I use to soak my parts up to 3 weeks or even more when I do not have time in the Tiger degreaser and then wash the remaining paint off with water and a tooth brush. It works great.

[Blacque Jacque 4]

Just a thought...........

Has anyone tried caustic soda / sugar soap ? the powdered stuff sold in DIY shops for degreasing.

I know it works for TS type paint, but I've seen it mentioned in conjunction with poly paint.