Stripping Primer with Alcohol

[StevenGuthmiller]

I have never used alcohol for stripping paint & I had a few questions for those of you that have.

I've used Super Clean, oven cleaner & brake fluid for stripping paint & have settled on Super Clean as the stripper that works the best for me.

However, I've always had problems removing primer cleanly with Super Clean & was wondering if anyone has had luck with isopropyl for that purpose.

Also wondering how safe it is for styrene.

Is it safe to let parts soak in isopropyl alcohol without damaging the parts? & for how long?

& finally, I'm pretty sure I've heard guys say to use 91%.

Is that what I need?

I have not used brake fluid in many years because I don't like dealing with the mess & disposal, but has anyone had luck with brake fluid for removing primer?

DOT 4?

 

Steve

[Jhedir6]

For styrene IPA is fine, I've not had any damaged parts and I've left stuff in to soak for weeks. I currently have an Audi R8 that had some sort of extraterrestrial paint on it that has been awful to strip in my IPA bath for like 3 months now and still no softening of the plastic. On resin, DO NOT use IPA it will soften resin to the consistency of mild cheese, and quickly too. I use 91% simply because that's what I was able to find. I've heard others using 93%, I'm guessing 93% would just work abit quicker.

As for primer, it depends on the type and manufacturer. I find on some kinds SC works best and on other types IPA works better. I have one bath of IPA and one of SC and just swap if I find one isn't working.

I've never used brake fluid so I can't help with that.

David

[Ace-Garageguy]

91%-93% is generally the strongest that's available commercially in drugstores and the like. 70% is more commonly available, but it's pretty much useless as a stripper...though it works very well as a cleaner.

I quit using brake fluid after a couple of older models became extremely brittle following a prolonged soak to soften an automotive urethane clear.

I realize neither of these deal with your specific questions, but more info on a thread is often helpful.

[Snake45]

92% alcohol works like a champ on some paints--old AMT and Pactra and new Testor lacquers, for example, and many water-based acrylics. Others not so much. It does NOT harm styrene including clear styrene. It might or might not work on enamels, if you let it soak long enough.

Put some alcohol on a rag or paper towel and rub it on the paint. If you get ANY paint on the rag, the alcohol might strip that paint eventually.

Not long ago I primed a '65 Chevelle wagon with Walmart primer, and then painted it with Walmart or Krylon (don't remember which) "quick dry" dark blue enamel. didn't like the way the paint came out so I dropped it in a tub of alcohol. The blue paint came right off and the primer was completely untouched--I didn't even have to re-sand it.

[Miatatom]

What brand of primer are you using? My favorite is Tamiya but it's almost impossible to remove. I use 91% IPA for !lacquer removal.

[StevenGuthmiller]

What brand of primer are you using? My favorite is Tamiya but it's almost impossible to remove. I use 91% IPA for !lacquer removal.

I usually start with a coat of Testors gray primer because it covers body work, etc. better than the Duplicolor sandable primers that I like to use.

Then I usually use several light coats of Duplicolor.

In the past, I've had good luck removing lacquer paints with Super Clean, but the primer can be a bear to remove fully.

Seems like the Duplicolor primer comes off pretty well in Super Clean, but the Testors stuff is very patchy.

Sometimes it comes off pretty well, other times not so much.

So, I thought if anyone had good luck stripping primer with anything else, I would strip what I could in Super Clean & finish off the primer with whatever works better for that.

Maybe I'll just have to pick up some IPA & give it a try.

I have several bodies laying around with primer left on them after stripping paint.

 

Steve

[peteski]

91%-93% is generally the strongest that's available commercially in drugstores and the like. 70% is more commonly available, but it's pretty much useless as a stripper...though it works very well as a cleaner.

Eh, those are weak! I get the "good: stuff, IPA99 at a local True Value hardware store (in the paint thinners section).  It is 99% IPA and sold in gallon containers. Not very expensive either.  Works even better than the others and still just as safe on Polystyrene or ABS.

[slusher]

I usually start with a coat of Testors gray primer because it covers body work, etc. better than the Duplicolor sandable primers that I like to use.

Then I usually use several light coats of Duplicolor.

In the past, I've had good luck removing lacquer paints with Super Clean, but the primer can be a bear to remove fully.

Seems like the Duplicolor primer comes off pretty well in Super Clean, but the Testors stuff is very patchy.

Sometimes it comes off pretty well, other times not so much.

So, I thought if anyone had good luck stripping primer with anything else, I would strip what I could in Super Clean & finish off the primer with whatever works better for that.

Maybe I'll just have to pick up some IPA & give it a try.

I have several bodies laying around with primer left on them after stripping paint.

 

Steve

Steve have you tried to sand it some and then soak it in Super Clean? I have removed primer in Purple Power that way before they weakened it..

[Miatatom]

I get the "good: stuff, IPA99 at a local True Value hardware store (in the paint thinners section).  It is 99% IPA and sold in gallon containers. Not very expensive either.  Works even better than the others and still just as safe on Polystyrene or ABS.

I didn't know there was 99%. I'll have to look for that. Thanks for the tip.

[Longbox55]

Eh, those are weak! I get the "good: stuff, IPA99 at a local True Value hardware store (in the paint thinners section).  It is 99% IPA and sold in gallon containers. Not very expensive either.  Works even better than the others and still just as safe on Polystyrene or ABS.

I would advise some caution with that. I've used it on a few different bodies I had to strip, and have found that it can soften the plastic in some cases. I mainly had issues with newer Revell-Monogram kits (the hood on the GMC snowplow kit to be exact) softening when soaked in IPA. Found the issue when I scrubbed the hood with a soft nylon brush, which gouged the hood. So far, I haven't had any issues with other brands of plastic, and it hasn't caused any issues with soft parts from action figures.

I'm not saying don't use it, only to be careful with scrubbing.

[MeatMan]

I saw a gallon of 99% at the barber shop I frequent this past week and meant to ask him where he gets it.

Purple power gets the primer off for me sometimes if I use a stiff brush, but it never gets it all.

[Miatatom]

I would advise some caution with that. I've used it on a few different bodies I had to strip, and have found that it can soften the plastic in some cases.

Thanks for that info Longbox55!

[peteski]

I didn't know there was 99%. I'll have to look for that. Thanks for the tip.

If they don't stock it at your local friendly hardware store, then can custom order it for you.

[Mike_G]

Pure denatured alcohol can be found in the paint section of most any home improvement store- the stuff I have is made by Kleen-strip and is called "SLX"

I normally use DOT3 brake fluid for stripping primer

[StevenGuthmiller]

I normally use DOT3 brake fluid for stripping primer

How does it work Mike?

 

Steve

[Mike_G]

How does it work Mike?

 

Steve

It works pretty good on stuff that isn't fazed by alcohol, you still need to scrub the primer loose with a toothbrush but the brake fluid works- I get the cheapest stuff available