Removing "dregs" from model

I've have some old heartbraker chronopia models I was going to paint for fun, but some them have this dark rough stuff on their surface. It's on the surface only, iv'e managed to get some of it removed(with paint removing liquid and old toothbrush, but it was slow and lots of work), and seems that the model under the stuff is undamaged. I figured the stuff is dregs from previous cast which got stuck on the following cast. Not sure though.

Anyway, has anyone else had this problem and do you know of any effective ways to remove it?

Can you show a photo?

Really not sure what you mean, casting doesn't generally work like that, it's a fairly 'clean' process and it's rare that metal stays in a mould after the models have been removed.

Ok, I found that some people reffer to it as leadrot, but the thing is, I don't think chronopia models have any lead on them.

http://www.smallcuts.net/articles/leadrot.jsp

That's exactly the same thing I have on my models(and those are chronopia ones too)

Crowmire":28zz2um5 said:

Ok, I found that some people reffer to it as leadrot, but the thing is, I don't think chronopia models have any lead on them.

http://www.smallcuts.net/articles/leadrot.jsp

That's exactly the same thing I have on my models(and those are chronopia ones too)

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Ok, leadrot is a chemical reaction within the actual metal that basically dissolves away the model into a powder. If, as you've said, the model is fine underneath whatever it is you're taking off, it could be the very start of leadrot, in which case scrubbing it off as you've done and hoping is your best bet.

Personally I just bin anything with leadrot as it's incredibly poisonous, and contagious to other models, but some people have had success with completely sealing the model in paint.

damn. I guess I'll just dump them. How does it spread? I've had them on same table as some of my WHFB 3rd ed elves...

Crowmire":2q9untlk said:

damn. I guess I'll just dump them. How does it spread? I've had them on same table as some of my WHFB 3rd ed elves...

Click to expand...

It's not instantaneous, but afaik, the gas given off in the chemical reaction that oxidises the lead can cause a chain reaction in other lead nearby. It generally happens when models are stored in an imperfect environment. Near each other on a table is unlikely to cause any issues.

Ok, thanks. I decided to try the cleaning after all, found some tips. . and this seems to be an issue with the chronopia line... so if there's anyone else with a soft spot for this Target games classic, be cautios when bying models.

warm water and a gentle scrub, file off any really bad bits, paint and varnish.

I had a problem with some Warzone models of about mid 90s vintage

I had stored them in their original boxes in a cupboard against an outside wall - I think they had probably got a little damp due to condensation in the cold cupboard. Where the metal was touching the grey foam they were packed in, they had corroded slightly. This was only where they were touching the foam, and they were slightly rough with a little of the detail sharpness being lost. There was a bit of gritty, white powderiness about the surface. When painted over it was barely noticeable, so it wasn't too bad, but I have never had this with anything else. Some GW and Foundry models were stored in the same place, also some on foam (but old GW foam), and they hadn't had the same problem. The corrosion has not worsened since they were moved. I have thrown all the foam away of that type - it seemed like there was something specific about it. Could this be the same problem that your models have? Interesting that they are same manufacturer.

Lead rot in models was first dicsovered/researched by naval museum curators. They cast some of the chandlery on model boats from lead, especially older ones, and would find them missing or decaying.

It is caused by an acid micro-atmosphere. Basically, inside sealed cabinets you can get acidic air! Cardboard also produces an acid environment, so keeping models in it is a bad idea.

Your best bet for avoiding it is well ventilated cabinets/storage. Or sealing them all individually in grip seal baggies.

The process that happens is that a chain reaction starts off, producing something like vinegar and lead compounds (nasty as Diesel monkey says). The reaction produces more of the acid too, so you get it spreading. To sop it you have to neutralise the acid and remove the "infected" parts. As has been advised, clean it out and give it a good scrub with water. Probably an alkaline scrubbing agent like household cleaner will help. Dry and keep in a neutral environment, or paint and seal.

I found the article, but on the "way back when" archive

http://web.archive.org/web/201102241419 ... ad_01.html

Pretty interesting stuff. Very detailed explanation of the whole process of lead rot.