I've read many positive comments on this method, and passed them on,
too, but I've never done it myself. I'm about to try it, as it's said to
be safe for styrene. But I have a couple of questions.
How long does it take, typically? Does it just soften the paint, or does
it lift it off the plastic? What about clean up of the stripped part -
soap and water?
Thanks for any and all tips.
Ferrous metals are iron based. Zamac is not a ferrous alloy.
Don't use lye on aluminum alloys; they disappear in the lye solution.
I've used lye to degrease steel parts (ferrous alloy) with no ill effects.
The impurities in many zamac castings perhaps cause it to react in lye as a
ferrous metal. Had some ruined car bodies some 30 years ago that really
did not like lye. Perhaps I should have added "pot metal" to my note.
Ferrous metals do NOT react with lye. Mild steel, tool steel, cast iron,
stainless steel - I've boiled them all in strong lye solutions to remove
oil and grease. The metals were not affected at all. After removing from
the lye and rinsing, the non stainless steels will rust VERY quickly
because the protective oils are gone. But the lye does not affect the
Zamac and pot metals are aluminum alloys. Aluminum and aluminum alloys
are destroyed by lye. You can watch the bubbling and foaming as the
| I've read many positive comments on this method, and passed them on,
| too, but I've never done it myself. I'm about to try it, as it's said to
| be safe for styrene. But I have a couple of questions.
| How long does it take, typically? Does it just soften the paint, or does
| it lift it off the plastic? What about clean up of the stripped part -
| soap and water?
I've used the commercial product Castrol Super Clean (known as CSC in
the automotive modeling world) and after a half-hour all of the paint came
off the 1:24 scale plastic auto body. It softened the paint and I
"scrubbed" it off with an old toothbrush.
Since neither of the first 2 replies saw answered your question (which
was "how does brake fluid work?", not "what else can I use to strip
paint?"), I'll try. It takes as long as it takes. More specifically, it
ain't fast; be patient. It basically softens to paint to the point where
it can be physically removed, so be prepared to use something to gently
scrub it off (a plastic scrubber, f'rinstance). After that, yes, it'll
clean up nicely with soap and water (the brake fluid is water-soluble).
The best argument against democracy is a five-minute
conversation with the average voter.
It's a technique I've used quite often.
I imagine the results will depend on the brand of brake fluid, the type
of paint being stripped, temperature ...
In my experience the paint surface softens for about the first 10
minutes and can be washed off with gentle application of warm water and
a tooth brush.
At about 15 minutes the reaction starts to change and the softened paint
begins to become rubbery. The depth affected seems to increase but the
outer softened layer seems to gain strength.
Further, (some) plastic left in brake fluid seems to change to a more
powdery surface feel, which I'm not happy with.
Because of those two factors, I use different stripping techniques for
diecast materal and for plastics. (or is that 'but for plastics.'? ;-)
- With diecasts I will place them in a bath of brake fluid for 12-24
hours, wash and return until it is clean.
- With plastics I paint on brake fluid and then wash after 10-15 minutes
and reapply until all the paint is removed. 3 or 4 applications has
always been enough.
The time is quite variable. On a hot summer day, with fresh brake
fluid, some paints run off the model and puddle in the bottom of the
pan in a few minutes. Other paints, colder day, fluid which had been
used a few times, and the time can be hours or sometimes, never.
Temperature certainly makes a difference. I've fetched a jug from the
basement and had it work very slowly. But as the fluid warmed, the
action accelerated noticably.
It varies greatly. I recall a couple silver cars with black lettering
where the letters fell off in one piece while the silver paint ran off
in streams. Sometimes the paint dissolves and runs off, sometimes it
turns into a gummy goo which must be scrubbed off, sometimes it
loosens and can be peeled off in sheets, sometimes it just sits there.
I've encountered great differences between manufacturers and between
different colors on the same model.
Unfortunately, I had much better luck 15 or 20 years ago than I do
today. I suspect changes in paint formulae and possibly changes in
brake fluid composition are the cause. These days, I'm disappointed
more often than not. The same can be said for every paint removal
nostrum I've tried. Lye does a very nice job on some paints, doesn''t
do a thing to others. Some folks swear by Pinesol, I've never had any
luck with it. Ditto for Goo Gone. Ditto for Simply Green.
Or even just hot water. I think, but am not certain, that brake fluid
is high molecular weight alcohols. Whatever the substance(s), it/they
mix readily with water.
I liked the part that went, "polyethylene glycol in the concentrations found
in DOT brake fluids reacts violently -producing a large fireball- with some
household chemicals; notably pool care products."
Sounds like a chapter form "The Anarchist Cookbook".
A couple tips.
The active ingredient in the brake fluid is volatile, so be sure to cover
the jar or pan in which you are soaking your component. I find this greatly
extends the useful paint removal life of the fluid.
I prefer to soak bodies in vertical jars or cans rather than horizontal
trays - they seem to take less fluid to submerge the component, and the are
easier to close re. the tip above. I have an old Planters peanut glass jar
that is perfect for a 40' HO boxcar body.
If you find that you don't have enough brake fluid to cover the component
you are soaking, remember you can raise the level by adding fillers to the
jar/tray. It happens that my wife keeps her garden and flower stuff near
the deep sink where I do paint removal, and she has a supply of glass
marbles she once used for some display. I find borrowing some of the
marbles works well to fill a soaking container, particularly if I'm working
on the occasional O scale piece, and so far has gone undetected by spouse.
Also remember that regular brake fluid (the DOT-3 or DOT-4 varieties at
least) are hygroscopic so they absorb water and in doing so change
composition. So that's another reason to use it in a sealed space (such as
an old glass fish tank with a well-fitting cover).
Yep that's a good idea.
Yeah marbles are really good since they're inert as far as brake fluid is
concerned and will have effect on the job at hand.
Craig Dewick - HO-Scale Railway Modeller and Professional Train Manager at
http://lios.apana.org.au/~craigd or firstname.lastname@example.org if you're game!
That is why IMO brake fluid is more trouble that it is worth for
stripping models. I also had bad experiences (softened, discolored
and frosted plastic) when I tried the brake fluid in the past.
There are plenty of less cumbersome methods. I use several chemicals
depending on the job at hand.
If I'm stripping a metal parts I use a strong stripper such as
"Aircraft Stripper". It contains chemicals such as methylene chloride
and it'll strip pretty much anything. There are few others available.
But if those are used on plastic parts they'll turn them into gooey
On plastic I use more delicate strippers. My arsenal includes
Denatured or Isopropyl Alcohol (or a mixture of one of those with a
little acetone), Polly S Easy Lift Off, Scalecoat paint remover,
Castrol Super Clean (or a generic equivalent) and and couple of others
which I don't recall at this point.
Some of those seem to work better with certain types of paints
(lacquers, enamels). I basically experiment. If one doesn't work I
dunk the part in another one until I find one that will do the job.
That is true. However, make sure to get one containing lye. Some of
today's oven cleaner sprays use other chemicals which might not strip
the paint or might actually melt the plastic. Oven cleaner is also a
pain to use as you have to spray it out which results in a fine spray
of very irritating mist (if you're not careful). I prefer using
liquids containing lye, such as Castrol Super Clean (or one of the
generic versions) or "Strip A Kit" from Hangar 3 Arlee (email:
doghaus at montana dot com).
On Sat, 10 May 2008 09:24:32 -0400, Wolf Kirchmeir
The Canadian Tire cheap brake fluid worked for me but getting yellow
paint off one Atlas/Roco ATSF GP-38 took so long the plastic was
affected. The expensive Canadian Tire brake fluid destroyed shells.
"I believe there are more instances of the abridgement
of the freedom of the people by gradual and silent
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