Recommendations for blasting car parts (melted plastic covered)

[02fanatic]

Need some advice on how to most easily clean some metal auto parts that were damaged in our house fire last year. I had parts stored in Rubbermaid containers, and the heat from the fire melted everything. I was able to salvage some parts (that are structurally ok) - metal bumpers, engine intakes, etc., but they are mostly covered with black soot and melted plastic (from the storage containers).

Any ideas how I can remove this stuff so I can restore/salvage these parts?

I am not that familiar with blast cabinets, soda blasting, or other blasting techniques, and before I buy the equipment, I need to know what might work best for this situation.

Many thanks for any help on this,

John

[bbvette]

Hi John - sorry to hear about the mess, I know about Rubbermaid containers for storage, I have a bunch of stuff in the Sterilite ones now. I also do a lot of glass bead blasting for restoration.....my guess is you will have to approach the parts by size and type to some degree. Clearly, bumpers are large, and will have to be done by a pressure blast system, probably with fine sand, but if you are trying to retail chrome, maybe there is a process that would soften the plastic without damage to the plating, you could ask a local plating house if they know of any chemicals. The bad part of the plastic, even on say the intake manifolds, is it is very hard to blast off, and you don't really want to concentrate a flow of abrasive on say a spot and have it crater the aluminum around it. If it is cast iron intake manifold,s that is far easier as they can stand more agressive media. The soot of course is no problem, and you could start with the media say soda if you wish, which is very non abrasive but will never cut the plastic off, but would clean off the soot....to see what you have to deal with better. Sorry for not giving a better answer, but clearly media cabinets are a reasonable way to start this project.....Craig

[02fanatic]

Thanks for the input Craig....I'm wondering if I should use a butane torch, etc. and try to melt the plastic off the aluminum intake runners, bumpers, etc. I hadn't thought of that before....kinda like stuck candle wax you know? Just a thought.

John

[bbvette]

Now that you mention it.......maybe you can do that outside and burn off the plastic, carbonize it, then use a blast media. It just may be the way to go.....Craig

[FrankyVW]

Blasting media will bounce over soft material, you'll need to heat up and scrape it or brush it off with a buffer and wire brush before you blast it. Wear a breathing mask, carbonized plastic and stuff makes hazardous toxic mixes you dont want to have in your lungs, especially if you are asmathic as me!

[wiseguy]

What if you used a heat gun to just get the material in a pliable state so that you could peal it off easier? It might be worth a try.

[chevy truck]

This may be too late for you as it's now Jan of '10. but if others find themselves in this situatiion, why not try using an old CO-2 (carbon dioxide) fire extinguisher or any other compressed CO-2 they can find. perhaps what is used for paint ball guns or something. I imagine the place you re-fill your welding argon/co-2 tanks will have it also. Anyway after almost 50 years in Fairbanks Alaska I've learned how fragile plastic is when cold. The colder the more fragile it is. I would think you could get it good and cold then tap on it with something hard and it should chip right off. Be aware that metal also becomes more fragile too, though not nearly as much as plastic. So don't start whaleing on it with a sledge hammer. I would not recomend doing this to remove plastic from plastic however. Just a thought