I need some help. I collect a construction toy that was popular in the 50s and 60s called Elgo American Skyline. You can build extremely realistic HO skyscrapers with these kits, good enough for HO scale railroad layouts. The pieces are injection molded glossy white polystyrene that gleam like polished marble in the completed skyscrapers - very aesthetic. Even today, these pieces are as white and shiny as they were when they were lifted hot out of their molds more than 50 years ago. Unless the kit was in a smoker's home. Tobacco staining has turned the exterior sides of such unfortunate pieces a dull, snot colored yellow. Really makes you think about what was happening to the kids' lungs who lived in such homes whose toys these kits were when they were new. Anyway, I've been trying to get the staining out - and I'm afraid it's soaked right into the molecular surface of the plastic. Nothing touches it, or even diminishes it. I've tried many, many different types of commercial tooth whiteners, bleaches - even an acne cure: no go. I have to be careful because too caustic an agent will destroy the plastic. So no acetone, no lacquer thinnner, no MEK. Yes, I could simply spray paint these pieces (and may wind up doing that), but I'd rather get the stain out if there's any way to do it without injuring the plastic. Any ideas out there? Many thanks - Mark Baird Alameda CA
Peroxide and sunlight. However, I really wonder if it is truly tobacco smoke that is causing the staining. Tobacco smoke tends to be a surface contaminent. Were these things stored in boxes?
Not sure this will work with tobacco, but i've seen several different ways to clean stuff like pasta sauce stains out of plastic: Leave it out in the sun. A single day of sitting in the sun can practically eliminate sauce stains. denture tables. They clean dentures pretty well, why not plastic? baking soda. I've seen it do some amazing things on stained nasty sinks. I don't remember the products name, but i once saw someone clean out a plastic bowl with something (came in a green box) that was designed for cleaning coffee pot stains. cleaned it out like magic! Try them all at your own risk, i can't promise there won't be unintended side effects on the plastic (like pitting or destruction), although most of the stuff doesn't seem to be too caustic.
<div class='quotetop'>QUOTE(Swanny1172 @ Jun 15 2007, 01:18 PM) [snapback]462530[/snapback]</div> Yes - but so are the pristine pieces with no staining at all. The staining is always on the exterior surfaces most heavily, and extant to a lesser degree on interior surfaces. The only factor I can think of the distinguishes a "clean" kit from a stained kit is the environment it came from - else ALL kits would have similar degrees of age tarnishing or embrittlement. I'll give the peroxide and sunlight treatment a go - thanks! MB
<div class='quotetop'>QUOTE(airportkid @ Jun 15 2007, 04:27 PM) [snapback]462536[/snapback]</div> Were the boxes stained with tobacco smoke as well? How about the inside of the box? I just find it hard to imagine cigarette smoke infiltrating a box.
That smoke is invasive as all hell. One of my grandfathers smoked cigars until the day he died... I know it's a bit different, but the smoke is all close enough... anyways, He was real big into miniatures (did it as his "retirement job"), and built my younger sister a very nice doll house (won a blue ribbon!). Even now, 10-15 years after he gave it to her, the thing still reeks of smoke whenever she takes the dust cover off (just a thin piece of fabric). I have no doubt that the cigarette smoke could easily penetrate a porous box and adhere to some plastic pieces.
Try a dab of toothpaste on a microfibre cloth, or just rub it in with your fingers. Baking soda and vinegar might help, too.
Won't sunlight degrade polystyrene? And toothpaste usually has silica, or some other fine abrasive, that may scratch the surface.......I think you like your models shininess too much for that. It sounds like this is of value to you. I'd be careful not to use a cure that may promote further damage. Maybe call Dow and ask them which of their products would be most useful.
I should mention that these kits are plentiful on eBay, they're not rare, so I can afford to be experimentally aggressive finding a solution (the sacrifice of a few pieces is no big deal). Also, any solution that requires hand work on each piece (e.g. hand rubbing or scrubbing) won't be practical, as there are literally thousands of pieces involved. What I need is a vat solution of some kind that I can toss all the pieces into and let sit for however long it takes to whiten them. Many thanks for all the suggestions thus far! To answer the smoke getting into the storage box issue: the pieces aren't stained (I don't think) while in the box, it's when they've been out sitting on display as a finished skyscraper for months or years that the exteriors get stained. Yes, the skyscrapers look that good that they'd be left intact on display for some time. (Also, once built, they're tedious as hell to dismantle). MB [attachmentid=8915] [attachmentid=8916]
Oooooooo, pretty! In that case, what about Oxyclean? I use a similar product that they sell at Trader Joes. It's a natural bleach alternative for chlorine. It's best if you dilute this in really warm/hot water as it'll dissolve much better than in cold. It's successfully removed rust stains from my stainless steel kitchen sink and it's not caustic, stinky or damaging to the environment. If that doesn't work, I would try an acidic solution like vinegar. I'd still stay away from sunlight as that may just yellow the plastic more.
I was going to suggest vinegar as well, just as an off-the-cuff idea. But if the kits are that plentiful on eBay, I'd probably just throw away the stained ones and buy more, after inquiring of the seller as to the condition of the pieces.
Thousands of pieces, you say? OK, skip the toothpaste idea. (The abrasive acts as a polish) Give the finished models a bath in warm soapy water and just paint them. If and when the tobacco stains ever bleed through the paint, you can call it weathering. You want your model railroad to have realistic-looking buildings, don't you? You should be staining them more.
Mark I don't know of any skyscrapers from the mid century which are not stained from pollution, so your pieces are more 'authentic' than if they were pristine. Settle on 'realistic look' and your work is done. Go flying, invite Pinto. Rumor is she gets high on height.
Automotive rubbing compound might work.I used it to polish the clear plastic headlamp covers on a 91 Previa van which had yellowed with age. This is after wet sanding with 2000 grit.
