Stripped resin body, now soft.

[aurfalien]

Hi,

I left a resin body in alcohol a bit too long, it got soft.

Whats the best way to harden it back up?

Thanks in advance.

 

Edited June 7, 2017 by aurfalien

[Jhedir6]

First... dont use alcohol to strip resin. Use Castrol Super Clean. 

If the resin hasnt lost it shape try putting it in the freezer. 

Hope it's not ruined

.

[aurfalien]

Hi,

Thank you for such a fast response.

Putting it in freezer now.  Should be ok, thanks for the wishes.

[espo]

Even Castro Super Clean can effect some resins. I lost one that way.   

[aurfalien]

Hi,

Yes that's why I didn't use it, warped some resin I had.

[aurfalien]

Hi,

The freezer worked for the most part.

I found this spray on super glue and will use it to further strengthen the body.

It was really rubbery, now its mostly stiff but still some parts are soft.

 

[russosborne]

you should always ask the manufacturer for their recommendation on cleaning their product.

Russ

[peteski]

True, but when was the last time you've seen a paint stripping recommendation provided in a resin kit?

[aurfalien]

Hi,

The odd thing is that the floor board didn't warp, only the body.  Both are very thick.

[StevenGuthmiller]

True, but when was the last time you've seen a paint stripping recommendation provided in a resin kit?

They will usually recommend a particular product or two for removing mold release agents.

Usually this will be Super Clean or Wesley's Bleche White.

Both work well as paint strippers in most cases.

I've never had problems with resin & Super Clean, but I'm sure it has a lot to do with the composition of the resin.

I've used it on Modelhaus & Flintstone stuff & have never had issues.

 

Steve

[Longbox55]

True, but when was the last time you've seen a paint stripping recommendation provided in a resin kit?

Modelhaus used to put stripping recommendations in theirs. Superclean was their suggested stripping agent.

[aurfalien]

Hi,

The body is mostly rubbery, are there hardeners one can use to stiffen it up?

Will a polyester resin hardener work?

[Zoom Zoom]

IMHO at this point your resin body is junk. Replace it or move on. You compromised the material w/alcohol, there's no magic blue pill that's going to stiffen it back up to be useful.

[Ace-Garageguy]

Hi,

The body is mostly rubbery, are there hardeners one can use to stiffen it up?

Will a polyester resin hardener work?

NO.

"Polyester resin hardener" is actually an oxidizer / catalyst, the most common one being MEKP...methyl ethyl ketone peroxide, and it ONLY has any effect on still-liquid ESTER resins. 

Most "resin" parts these days are very likely to be urethane-based anyway, and once cured, aren't going to be affected any further by catalysts or hardeners...especially those used in resin systems based on different chemistry.

MEKP is also highly toxic and can be dangerous if handled improperly, is corrosive to soft tissue and can cause explosions and blindness.

Edited June 11, 2017 by Ace-Garageguy

[Art Anderson]

Hi,

The body is mostly rubbery, are there hardeners one can use to stiffen it up?

Will a polyester resin hardener work?

As others have stated, no.  Polyurethane resin,  thus compromised, will harden up over time, but if your parts (body shell?) are warped (and almost assuredly they will be) they likely are beyond saving.  I had, on several occasions, a customer or two who did pretty much what you did, with the same results, even with a warning clearly printed on the cover page of every catalog I sent out, and included with every order.  I even bought back (as in replaced) a couple of such bodies, to show potential buyers what would happen with commercial paint strippers.

Art

[aurfalien]

Hi,

Thanks to every one for taking the time to reply.

I've nothing to loose and can be tenacious at times, I am having some success using thin super glue.  I'll update with final results once the day is complete.

The body is the wonderful Fisher 908 so I don't wish to give up so easy.

Edited June 11, 2017 by aurfalien

[aurfalien]

Hi,

I found a solution to save it.

I'm pouring very thin coats of 2 part resin inside the body, small sections at a time.  The set time is quick and I let it sit a few seconds before applying to further avoid running.

This is to give it more structural integrity.  I can deal with the outside using putty etc...

In celebration, I am buying the HRM 917 engine kit from Randy and will build a prototype 908 CanAm sort of thing.

I'm pleased.

Edited June 11, 2017 by aurfalien

[MrObsessive]

Brian, I don't want to be a killjoy, but I'd be suspect of painting over a surface that was once stable, is now compromised by the stripper that you used. Seems to me that the stripper leached into the resin (porous) and softened it up as you described. I'd be wary of those same chemical compounds which may still be "buried" in the resin, making their way through to your paint job over time.

I've not built many resin kits, but this is more of a skeptical approach on my part as I've had strange things happen over the years with a paint job on plastic after it was stripped.

It's up to you, but just a word of great caution where you might want to test your paint in a small area-------wait a bit to ensure there won't be any surprises later. 

[aurfalien]

Hi Bill,

Thanks for the cautionary note.

I'll then plan to use a very good primer/sealer to lessen any possible leaching effect.

[peteski]

While leaching might be a problem, how will paint/primer/sealer remain well-adhered to a relatively soft surface of the body?

[aurfalien]

Hi,

Only one way to find out, which will be soon enough.

There is lots of prep work I am doing in the mean time.  I'll post pics when ready, this should be very interesting.

[Zoom Zoom]

Have you even thought about asking Paul Fisher if he could replace the body for you? 

[aurfalien]

Hi,

Well I'm enjoying trying to fix it and don't wish to spend any more money.  I'm also learning more.

[Snake45]

I'd try to let it dry out for a few weeks, and see if it comes back to normal. If not, I might try coating it with superglue, as I do with common putty to strengthen and stabilize it.

Common naphtha (lighter fluid) will soak into kit styrene, and not melt it, but will turn it crumbly, like a cookie. But let it dry out thoroughly and it's fine. I wonder if something like that might happen here.

[aurfalien]

Hi,

Great idea, I've no issues waiting.

I stopped coating the under body with resin as I did a small area for testing.  I've let it soak in warm water over night hoping to leach out any chemicals.

I noticed the water was a bit different after words so the soak did something.

Will let it dry for a few to see what comes of it.