How to safely strip paint from a promo

[chriscarroll.ogre]

I have just purchased an old promo that was customized and painted at some time. I'd like to strip the paint off, but not harm the old plastic. This promo dates from 1959, so I am not sure how fragile the plastic is. I've read up on the various techniques for removing paint from an injection plastic model, and from a resin model. But are there any special considerations that I need to take in mind for a quite old promo?

Any help at all would be much appreciated! Thanks!

[Ace-Garageguy]

1959 is right in the transition period of promos going from acetate to styrene or ABS (simply a toughened styrene). Art Anderson and a few others on here should be able to tell you what material you have depending on what car it is.

In general, unless an acetate model has been stored in some kind of suspended animation or time warp, by now it will be showing the characteristic shrinking and warping they're prone to.

If the model isn't warped, it's a pretty good bet it's styrene.

I'll leave any further responses to the experts on this information.

[Mark]

Would it be possible to post a picture or two?  No 1959 annual kits (AMT, SMP, or Jo-Han) had engine detail or an opening hood, so most people call all of them "promos" when in fact many of them are assembled kits.  I'm pretty certain the switch away from acetate for promo models didn't start until '61 ('64 for Jo-Han), so if you have something from '59 that isn't warped or distorted then it may well be a kit.

[chriscarroll.ogre]

I haven't received it yet, so I can't post any other pix than the ones the seller had. The model looks butchered to me; but I only want the greenhouse area: roof area, glass, etc. I intend to try to resin-cast a copy of the roof and convert it to a 4 door model, to then have a copy to graft onto 1959 and 1960 Chevy models. All to make a 4 door sedan. 

[chriscarroll.ogre]

As you can see, the roof area is straight, and that is all that I want from it. But I'd prefer to have the paint off of it, especially the 'glass' areas. As long as I can make a decent, straight resin cast of the roof, and have the glass area so that I can vacuum form replacements, I'm happy.

[chriscarroll.ogre]

Here's what the underside looks like

[disabled modeler]

looks like an old Johan kit to me....I have a 59 Cadillac 4 door like it that is pretty decent still has the body trim in tact...mine has the same chassis.  You should be able to strip it with brake fluid safely...if someone is interested in mine pm me.

[ChrisBcritter]

Yep - that's a built kit, not a promo. That old Jo-Han kit plastic is very hard and can be brittle, so be careful.

[gtx6970]

Yep. like mentioned . Heavily sanded on Johan 1960 Cadillac KIT. Far to straight to be an original promo. Depending on what kind of paints on it, I would start with brake fluid and see what they gets me. If that doesn't work I would advance  to Wesley bleach white or Castol Super clean

 

 

1960 Johan  Promos were still acetate ( as a fun fact  Johan promos were acetate up to and including 1963s )

1964 they were Stryene

 

here is your typical view on a 1960 Promo ,,,of any particular promo

Edited December 30, 2016 by gtx6970

[chriscarroll.ogre]

Thanks all for the help! I didn't know that about the kits vs the promos. Good to know. There was an opportunity to buy a warped promo with a mostly straight roof, but I passed it up to get the straighter one I posted pics of. I got it at a bargain price, too! I think I'll try the more gentle solutions first, then if necessary work my way up to tougher ones as necessary. I read somewhere that Simple Green was a gentle soak. Anyone tried that stuff?

[espo]

Thanks all for the help! I didn't know that about the kits vs the promos. Good to know. There was an opportunity to buy a warped promo with a mostly straight roof, but I passed it up to get the straighter one I posted pics of. I got it at a bargain price, too! I think I'll try the more gentle solutions first, then if necessary work my way up to tougher ones as necessary. I read somewhere that Simple Green was a gentle soak. Anyone tried that stuff?

This roof may work for your Chevrolet build IF it is a pilard four door sedan. The hardtop body style used a flat top type roof  with the top hanging over the rear window.  

[Art Anderson]

This roof may work for your Chevrolet build IF it is a pilard four door sedan. The hardtop body style used a flat top type roof  with the top hanging over the rear window.  

The hardtop roof is also too low in height--about 2.5 scale inches lower in real life than that of the sedans.

 

[Tom Geiger]

Also note that those early Johan Caddys were an odd size, not really true to 1/24 or 1/25 scale.  Measure it all off before you cut anything.  That roof may not match up to the modern kits, which are usually right on scale.

[chriscarroll.ogre]

Good points, all around. I just received the Caddy, and it does look more like an old kit than a promo, so that's reassuring. The chassis and front and rear chromed pieces fell right off with the screws removed, but the interior tub and glass are seriously glue-bombed into place.

Now I'm a little concerned about how to safely unglue these pieces. I'd read that some of the stuffs used to dip a model in to strip the paint can also remove the glue. I'm hoping that the stuff that was recommended to me, called LA's Totally Awesome!!!, might loosen the glue, too. If it doesn't work, I've got Simple Green I can hit it with, too.

BTW, just out of curiosity, I poured a little 91% alcohol onto a blue shop rag and rubbed on a lower body part for ten to fifteen seconds, then rinsed under cold water. The following image shows the results. I am very impressed!

[Snake45]

BTW, just out of curiosity, I poured a little 91% alcohol onto a blue shop rag and rubbed on a lower body part for ten to fifteen seconds, then rinsed under cold water. The following image shows the results. I am very impressed!

That's a common reaction with many of the old AMT lacquers (and the new Testor ones).

[disabled modeler]

Just take your time on her....the guys are right and very good advise.  I stripped an old 60 Ford HT promo once in brake fluid...was a bad idea due to the weaker plastic they used for it. Yours should be the better stuff and easier to strip with out and damage to it.

[Mark]

DON'T use brake fluid on early Jo-Han plastic!  My own experience with that combination had the plastic turning extremely brittle, to the point where it is not workable.

One guy I used to know did a lot of building "to order" for a doctor who was in one of the Oldsmobile clubs.  This guy did great paint jobs, but on the occasion where he didn't like his work, into the brake fluid it went, even still wet.  When he quit building, I bought his kits and parts.  In there was a '68 4-4-2 body that got the strip treatment; the detail on the whole thing is washed out and the plastic is more brittle than usual for Jo-Han.  I might be able to save it as a funny car body, but that's about it.  This guy was bugging me to sell him my '68 kit; I'm glad I kept it because it might have suffered the same fate as this one.

I once bought a built '65 Chrysler hardtop with the intention of stripping/rebuilding it.  Apparently it had gotten rebuilt at least once in the past.  I didn't use brake fluid on it, but even so parts of the body literally crumbled and fell off when I pulled it out of the strip tank.  Other than the body, the parts are all still in good shape.  The windshield from that one got set aside for an unbuilt '66 convertible that I picked up for cheap on eBay.  That one had a cracked windshield that probably scared some bidders off, because Modelhaus didn't offer replacement glass for it, at least at the time. 

[Art Anderson]

Also note that those early Johan Caddys were an odd size, not really true to 1/24 or 1/25 scale.  Measure it all off before you cut anything.  That roof may not match up to the modern kits, which are usually right on scale.

Tom (and all), The JoHan '59 and '60 Cadillac Fleetwood 60 Special 4dr sedans are a mixed bag as for dimensions.   While the overall length of the models in question is too short, and the body is exactly 1/8" (three scale inches too narrow), believe it or not, the "greenhouse" (roof from the bottom of the windshield to the bottom of the back window is right on the money for length.  I know, as when I mastered the '59 Biscayne 2dr (all GM two- and 4dr 6-window sedan bodies used the same roof stampings as well as the same A & C posts!), I took copious measurements off the real 1:1 '59 Biscayne 4dr sedan that was in my driveway at the time (1994-95).  I simply widened the Cadillac sedan roof with a strip of .060 X .125 inch Evergreen styrene, used the windshield frame & header from the AMT Trophy Series '59 El Camino for the correct height ('59 GM sedan roofs are right at 2.5" higher than the harddops and convertbiles).  I also had to widen the JoHan rear window glass by .125", and use that and the El Camino windshield as vacuum-forming masters.

Art

[chriscarroll.ogre]

Great info and tips, Art! Thanks a bunch. None of that work seems to be extreme. I look forward to the challenge of making it work!

[chriscarroll.ogre]

UPDATE: After an overnight soak (about 21 hours at this point), this is the results of a dip in LA's Totally Awesome general purpose cleaner and degreaser. In picture two you can see how the paint is bubbling up and even coming off as dust into the liquid. In picture three, you can see the results of just a few seconds rubbing with a finger in rubber gloves. I'm pretty darned impressed!

The cleaner seems to have no impact on the glue, 'tho. Looks like I'm gonna have to cut my way thru all that glued-together plastic after all.

[ratdoggy]

Cool. I know for a fact that the Dollar General store has the Totally Awesome on the shelves!

 

[chriscarroll.ogre]

Two days's soak and some gentle scrubbing with a toothbrush has all the paint off except for minute amounts down in crevices, like the window trim and door panel lines. I think it did weaken the glue a bit, too, because it came apart with only a little bit of effort. LA's Totally Awesome totally works!

[crowe-t]

I like to use 91% Isopropyl Alcohol to strip paint.  It's safer to use and doesn't seem to affect the plastic.