[biotechee]

Well, if I decide to keep my PU splitter, I will need to repaint it. I'd like to remove the old paint, of course, before I attempt to paint it the new color.



What is the best way to go about removing the old paint without damaging the polyurethane? I am nervous about using solvents for fear of "melting" the polyurethane.



Do I just need to sand it off?



Thanks in advance



P.S. Hopefully I put this in an appropriate area- I didn't locate anything more suitable- might have missed it.

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[PorscheDude]

Sand it. Use 220 grit to start with.

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[flash]

yup - if you're going to do it yourself, sand it - time consuming process, as it has to be hand sanded, not DA or orbital



if you want to pay somebody, a body shop can send it out to a bumper dipper and get it off - probably about $200

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[biotechee]

Sand it I shall!



Bumper dipper would be easier, but I'm in no rush to spend the money for that.

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[flash]

understood - i've had problems with that before too - the last time i did a bumper cover, they didn't completely remove the chemical - 4 days after it was painted, the paint literally fell off

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[biotechee]

That would seriously piss me off!



There's a very well respected body and paint guy near my house... I had them do my Jetta trunk lid for me.



He does a ton of local dealership business... Since the Jetta trunk lid was easy, he agreed to do it. I think he is becoming more of an insurance shop lately so I'm bummed about that.

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[flash]

lol - no worries



there were a LOT of problems with the body shop that did it - against my better judgement, after having had problems with them before on a different car, i went ahead and gave them another chance - should have trusted my instincts



the ultimately got dinged for it - it was an insurance claim - i took it to a different shop, at the direction of the insurance company and got it taken care of - the insurance company then pulled the first shop from their recommended list

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[jeff968]

Another option is a professional non-chemical stripper. I have a guy near me call american dry stripping who uses low pressure stripping methods such as walnut shells. It is like sand-blasting and won't damage the underlying material but it does a great job at getting in the corners. You would have to spend some money though.

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[biotechee]

yeah- I've had some smaller parts blasted before with walnut shells- works like a charm. the splitter is pretty big though so finding someone local with reasonable rates is going to be difficult.

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[PorscheDude]

Sand it, it will only take an hour or 2.

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[jlm968]

Chemical stripper, available at any parts store, and don't expect it to be a 2-hour job. More like an afternoon, and then a second application the following day if you have a lot of paint/primer to deal with.



Sanding is not the right way to do this job; if you're not careful sanding, you could dig into the plastic and just create more work for yourself.



I've had a lot of vehicle bodies and parts dipped in my day. I don't know of a facility that will work with plastic or fiberglass, as the dipping itself is generally akin to an electroplating process in reverse and thus only works on metal. Parts come out so clean that rust spots can begin to form immediately if a protective powder is not applied immediately; and you have to get an etching primer on the part(s) quickly. Again, I don't think they'll dip plastic parts.

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[flash]

they do, at least PU parts like bumper covers - had it done a few times now - only the last one was a problem - as i said though, it isn't cheap, and the body shop sends it out to a place where that's all they do

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[968Syncro]

I'd be very careful with sanding! I refinished the bumper cover recently, and the problem is that the paint and polyurethane are different hardness, the paint is a much harder material. So if you get through the paint, and mistakenly keep going, you start to wear down the plastic. If you create heat from the friction, the plastic starts to ball up into tiny globules, and you will get a really uneven surface with high spots where there is a bit of paint left, and low spots where you've started to wear away the plastic. (at least this was my experience with the bumper cover). I left the old paint on, and only repaired spots. So the process was: sand, ooops....then fill, then prime, then sand, then ooops... too far, need more fill, then dry, then prime, the sand, then ....ooops just a tiny bit too far,..... you get the idea. (I am a layman!). If the splitter is a hard plastic than the bumper cover you might have better results, but certainly don't use sanding to remove paint from the polyurethane parts.



Roland

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[jlm968]

I've never found anyone who would dip plastic parts, so I don't know about the expense. I get metal body parts dipped frequently because it's so thorough and a time-saver for me. I had an entire '69 GTO dipped for $900 (main body, trunk, doors, hood, fenders, grill support, etc.), while we bead-blasted the frame in our own shop.



Here's link to a product many bodyshop supply stores carry for stripping plastic partsBulldog:

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