Paint Removal made easier with a Sconic cleaner and Super Clean Purple

Since I buy a fair number of poorly painted miniatures off eBay  that I strip the paint off to repaint I also spend a fair bit of time removing the paint.  Over the years I have tried a variety of different removal agents listed from mildest to most toxic / caustic: Simple Green, Rubbing alcohol, acrylic brush cleaner, Super Clean Purple, Poly-S paint remover, spray on paint remover or furniture stripper, acetone and lacquer thinner.    The more toxic substances (oven cleaner, spray on paint remover and Lacquer thinner) seem to work best but they are dangerous and unpleasant to work with.  Some cleaning liquids work better than others depending if the figure was primed with solvent based paint, or if enamel or acrylic paint was used and varnish.  In terms of effectiveness balanced with not creating a toxic hazard Super Clean Purple has become my go to choice, with oven cleaner for really stubborn paint coats. You need to wear gloves with all of them plus adequate ventilation and / or a respirator mask for Oven Cleaner and the more toxic liquids.  There is often a considerable amount of scrubbing that needs to be done with an old toothbrush or other stiff brush plus digging out paint from crevices with a dentists tool or etching tool. It also usually takes 6  to 24 hours including soaking time.

I was curious if the sonic cleaners I have read about would make the process easier.  So I purchased Magnasonic Professional Ultrasonic Jewelry Cleaner with Digital Timer and used it with purple Super Clean liquid in the bath to see how it would work on an old figure I wanted to strip.

Below is the test Figure, a Dark Elf Assassin RPG figure from the mid to late 1980s.  Not sure about the paint used, my guess is acrylic with no  primer.

Back of test figure

Front of test figure

 The test figure was put in the Magnasonic cleaner, by opening the top and putting the figure in the plastic basket that fits inside the metal bath, then I added just over a cup of Super Clean purple (instructions say to add a cup of liquid to avoid damage to the machine) and turned on the machine for the full 480 seconds maximum time.

Magnasonic cleaner in progress,

 I must admit when I pulled the figure out after the timer went and it stopped I was a bit disappointment, I was hoping for a bare metal figure, but instead most of the paint was still on the figure.

Just out of the cleaner

However once I took the toothbrush too it the paint came off much easier than it would have if it had just soaked in Super Clean or oven cleaner over night.  I also rinsed the figure with hot water.

Cleaned briefly with a toothbrush front

Cleaned briefly with a toothbrush back

However as you can see there is still some paint on the figure in more recessed areas so I put him back in the cleaner for two more sessions and most of the paint came off after another few brushes with the tooth brush and rinsing with water. However there was some blue paint remaining in a deep recess beside the figures left arm that holds the crossbow, it was too deep for a toothbrush to reach. See picture below.

Remaining blue paint.

So I pulled out an etching tool, similar to a dental tool and scratched off the paint. Normally this is a difficult time consuming job as the paint comes off in little pieces. But in this case it came off easily in one or two scrapes in one piece.

Figure cleaned of paint,
etching tool above.

So while the sonic cleaner is not a miracle tool that strips all the paint off on its own,  it makes the job of scrubbing the figure with an old toothbrush much easier and less time consuming as the sonic waves break the paint to metal bond.  The job took roughly 30 minutes so a big improvement over the past methods that required overnight soaking and a lot more scrubbing and scraping.  The bath is large so you can certainly fit a lot more figures in at one go as the bath holds 600ml..

As an added bonus the sonic cleaner reduces the soaking time from 8 hours to less than 30 minutes which might mitigate against damage to lead figures.  Why?  It has been claimed that Super Clean can damage old figures (pre 1987?) with a high lead content as it causes a phosphate chemical reaction that etches the lead darkening or tarnishing the figures and sometimes leaving phosphate deposits. Therefore it is claimed high lead content figures should only be soaked in it for a short period of time then rinsed off with water, see:

https://www.dakkadakka.com/dakkaforum/posts/list/756071.page

Based on personal experience I can say that Super Clean sometimes darkens or tarnishes older lead figures, but I have never seen any phosphate deposits, visible etching or evidence that paint adhesion is less successful on darkened or tarnished lead figures.  I am also dubious about the veracity of the  claim that Super Clean causes phosphate etching as the product is labelled as "phosphate free". It seems unlikely that a phosphate free cleaner can cause phosphate etching, but that is a question best answered by a chemist so if there are any chemists reading this please comment.  Keeping all this in mind it might be best to err on the side of caution and limit the soaking time of  high lead content figures in Super Clean.

Of course once you finish removing the paint you should rinse the figures in water, then completely clean figures with dish-washing liquid and water or TSP cleaner and water then rinse in water again to ensure you have removed any traces of whatever paint remover and cleaner you were using.  Let the figures fully dry and prime them.

I am not sure if it is a good idea to keep the Super Clean in the sonic cleaner's bath long term, plus I may wish to use other cleaning agents in it.  Accordingly I have removed  the Super Clean purple from the sonic cleaner bath and stored it in a jar as it can be reused many times.  This was problematic as there is no spout on the bath so pouring out the Super Clean into a jar can be a messy job with lots of spillage, a turkey baster or large syringe is a good tool to use for this to avoid pouring.

Update May 28-29, 2020: Using Simple Green in the sonic cleaner on a 1985 high Lead content figure.

Based on the potential (if unsubstantiated) claim that Super Clean purple might damage older high lead content figures I used Simple Green in the Sonic cleaner to remove paint from this Citadel C29 Jabberwock monster miniature sculpted by Nick Bibby cast in 1985. It likely has a higher lead content compared to later figures.

The Jabberwock at the start

The Jabberwock appears to have been primed with a brush on water based white primer (maybe Citadel smelly primer or Gesso) then painted with acrylic paint (Citadel?).

Jabberwock in the Sonic cleaner

Simple Green

Simple Green added into the bath of
 the sonic cleaner

480 seconds of cleaning

 After this initial cleaning I removed the miniature and scrubbed it with a toothbrush.  Practically not paint came off, the Simple Green is proving to be much less effective than the purple Super Clean.

After one sonic and tooth brush cleaning with simple green

I put the Jabberwock back in the cleaner and gave it two more sonic cleaning sessions at 480 seconds and let it soak for 4 hours and scrubbed it vigorously with a tooth brush and rinsed in hot water.  As you can see below a lot more of the paint came off but some still remained.

After two more cleanings, a four hour soak and scrubbing.

I left the miniature to soak overnight (12 hours) and then game it another 480 second sonic treatment and scrubbing with a tooth brush, then a brass wire brush and scraped some of the  hard to get at recessed areas  with a dental tool, this removed most of the paint but there is still some on his back between the wings as you can see below.

Another sonic treatment, 8 hours soaking and
cleaning with tools in the background.

The miniature is now soaking again in Simple Green and I will attack the remaining paint tomorrow.  There is no doubt Simple Green is not as effective as Super Clean but it does not seem to tarnish the metal.  You still need to wear gloves and have good ventilation using Simple Green.

Update May 30, 2020

Another 24 hours of soaking in Simple Green and two more sonic cleans plus scrubbing and scarping have made little difference to the recessed areas where the green paint remains.

Green paint remains near wing

Green paint remains on back

Green paint under wing and by neck

 

Time to try something else, I have applied some Easy Off oven cleaner, the main active ingredient in it is Sodium Hydroxide.  I will let it sit in a baggie for a few hours.

After so more scrubbing and work most of the paint was gone  other than some under the wing that was particularly stubborn, it may be green stuff or coated in glue.  I noticed some areas were a light grey, possibly primer or oxidation caused by the oven cleaner.  I tried to remove this with acrylic paint remover, acetone, alcohol and Super Clean but only scraping removed whatever it was.

right side

left side

Head showing some grey oxidation or primer.

Drying

While trying to get the remaining green stuff off the half of the wing glued to the miniature broke off, likely weekended by the oven cleaner or acetone. Blog to be continued as Assembling and Painting the Jabberwock.