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General Modelling Forum => Tips, Tools, and Techniques => Paint, Primer, Thinner, and "Future" ("Klear") Forum => Topic started by: Hornet97 on September 26, 2020, 09:27:43 am

Title: Removing paint
Post by: Hornet97 on September 26, 2020, 09:27:43 am
Hey guys sadly one of my RF-4C models had an unfortunate fall and now needs to be repaired and I was wondering what's the best way to remove the paint from the model without further damaging it? Thanks  :cheers:
Title: Re: Removing paint
Post by: 63cpe on September 26, 2020, 10:49:01 am
I use natrium hydroxide (NaOH) for it. Be sure to wear gloves and safety glasses! Depending on the type of paint to be used it's off in 30 minutes up to 24 Hours.

Step 1. Get the plastic parts in the NaOH. Rub all painted surfaces frequently with old toothbrush (that's why you have to wear the gloves and safety glasses) let it soak for a while.....and presto. It won't do any damage on the plastic but might cause some glued parts to get off.

Step 2. Oh, get plenty of Cola (the regular one) whiting reach. To neutralize the hydroxide. Make sure all hollow also get rinsed on the inside with the cola.
Lemon juice works too, but usually in short supply in the 63cpe houseshold ;-)

Step 3. Rinse with plenty of water (to take the sugar from the Cola out and rests of the hydroxide)

Did many planes this way: the latest is a short skyvan. Biggest till now: B-52 (be sure the SWMBO is gone for some hours ;-)

Cheers!
David aka 63cpe
Title: Re: Removing paint
Post by: Old Wombat on September 26, 2020, 06:57:17 pm
Any weakish vinegar solution would work as a neutralising agent, too, & is probably cheaper than either lemon juice or cola.

Note: natrium hydroxide (NaOH) is also called sodium hydroxide (eg: lye or caustic soda).
Title: Re: Removing paint
Post by: zenrat on September 27, 2020, 03:22:05 am
Brake fluid.  Although parts left soaking in it for too long (weeks rather than days) can become embrittled due to the brake fluid leaching out the plasticisers  from the styrene.

If making ones own Sodium Hydroxide solution (which is bonza at removing chrome plate) by mixing Caustic Soda crystals and water then beware that it is an exothermic reaction and the resulting solution will be hot enough to warp styrene parts.
Don't ask me how I know this.
Also, don't use an aluminium container.

Title: Re: Removing paint
Post by: PR19_Kit on September 27, 2020, 04:01:51 am
Dettol.
Title: Re: Removing paint
Post by: ChernayaAkula on September 27, 2020, 04:43:07 am
Revell Airbrush Clean should also work. It's basically a re-bottling of stuff called Dowanol.
Title: Re: Removing paint
Post by: NARSES2 on September 27, 2020, 05:47:07 am
Dettol.

Really ? Never knew that. It's my "go to" disinfectant
Title: Re: Removing paint
Post by: PR19_Kit on September 27, 2020, 07:21:22 am
Dettol.

Really ? Never knew that. It's my "go to" disinfectant


We had a discussion about it on here when I was doing my son-in-law's Mustang car model. I screwed up the paint on the boot lid (trunk...) and had to strip it off, someone suggested Dettol and I tried it.

Worked a treat, plus the car was wholly germ free as well.  ;D
Title: Re: Removing paint
Post by: Dizzyfugu on September 27, 2020, 08:29:39 am
Brake fluid is a thorough but also very aggressive and messy methid - it not only loosens old paint of all sorts, it also sucks the softener out of the styrene and makes it brittle. Beware!

My personal favorite for stripping paint is a "bath" in oven cleaner foam. Takes a while (1 week recommended, repeat if necessary), but it is much less aggressive than brake fluid and still surprisingly effective.
Title: Re: Removing paint
Post by: major on September 27, 2020, 05:36:45 pm
My personal favorite for stripping paint is a "bath" in oven cleaner foam. Takes a while (1 week recommended, repeat if necessary), but it is much less aggressive than brake fluid and still surprisingly effective.


 :thumbsup: Always worked for me.
Although, Humbrol gloss red is impervious to It, and any other method, other than industrial sandblasting!  :rolleyes:
Title: Re: Removing paint
Post by: Hornet97 on September 27, 2020, 09:50:38 pm
Awesome help thanks for the information guys I'll use it wisely and keep the RF-4C away from the cat afterward  :banghead: :thumbsup:
Title: Re: Removing paint
Post by: Dizzyfugu on September 28, 2020, 12:26:00 am
My personal favorite for stripping paint is a "bath" in oven cleaner foam. Takes a while (1 week recommended, repeat if necessary), but it is much less aggressive than brake fluid and still surprisingly effective.


 :thumbsup: Always worked for me.
Although, Humbrol gloss red is impervious to It, and any other method, other than industrial sandblasting!  :rolleyes:

Yes, glossy enamels can be hard to remove with soda-based cleaners - they need "openings" to creep under the paint layer, so some sanding should help.
Title: Re: Removing paint
Post by: Nils on September 28, 2020, 01:56:35 am
im about to experiment with nail polish remover, Acetone-free of course.
should work i heared.
Title: Re: Removing paint
Post by: Rick Lowe on October 14, 2020, 02:31:32 am
A few years ago those in the US were swearing by Castrol 409. Unavailable here, of course... 

I've recently tried Simple Green, a dishwashing concentrate I got from a hardware store, though it's probably in supermarkets too..

I left the parts wrapped in a paper towel soaked in the stuff for a week, but it worked - you have to use a bit more elbow grease than other methods (a fingernail, a gentle rubbing with a wooden stick) but it works and is a lot less inimical and messy (and staining) than either brake fluid or oven cleaner.

It will even take off auto store spraycan primer, so it's pretty effective. Works on gloss enamel (again, spraycan) too.

And any left over you can use for washing your dishes!  ;D
Title: Re: Removing paint
Post by: Old Wombat on October 14, 2020, 05:50:10 am
So, a quick rinse & the parts are washed clean of oils, etc., too! ;D
Title: Re: Removing paint
Post by: Rick Lowe on October 14, 2020, 05:31:51 pm
So, a quick rinse & the parts are washed clean of oils, etc., too! ;D

Precisely!  :thumbsup:
Title: Re: Removing paint
Post by: dumaniac on October 15, 2020, 03:29:57 am
I didn't know about Detail. I usually use oven cleaner - sodium hydroxide - wear your oldest cloths - it can flick around directly or in running water. Plastics sees completely undegraded.

Dettol sounds great.I remember it as a kit half a century ago.