Audi 90 quattro 20valve

Audi 90 quattro 20valve

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Yertis

Original Poster:

18,082 posts

267 months

Monday 2nd March 2015
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Inspired by dr_gn and by the need to clear some space I've decided to get on and tackle what passes for my 'stash'. I did at one time have big stash but flogged it to Plastic Pastimes in Poole in about 1992. This stash is just a few kits that escaped that cull plus some others that I've accidentally purchased over the last 20 years. Most of my modelling gear of youth has long gone, but I have found one of my files and some others that I'll be resurrecting, including my beloved Super '63 airbrush.

So, first up is a model I obtained from HLJ.com, on impulse, about seven years ago. My brother had a real one and I thought it would make a nice gift. I made a total lash-up of starting it though, mainly through receipt of bad advice – someone told me you could spray car aerosols straight onto polystyrene provided you misted it on. Well you can't, and in one or two places the paint started to melt the plastic and the finish just looked grim, all kinds of reactive effects. The second lesson I learned is that tinned model paint has moved on, in the sense that it's gone backwards, and those bits that I brush painted also looked awful. So here the story begins, with a request for some advice. I've bought the brake fluid – how should I handle it to remove the paint? I've thought of total immersion but this is a 1/24 body shell and would need a lot of fluid. Is it OK to paint it on, like Nitromors, and just keep rebrushing and agitating?

Once I've removed the paint I'll be priming and prepping the shell properly, and then digging out the airbrush. Here's the starting point:


Yertis

Original Poster:

18,082 posts

267 months

Tuesday 3rd March 2015
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Thank you dr, let the fun commence...

Yertis

Original Poster:

18,082 posts

267 months

Saturday 7th March 2015
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Let's see how this goes...


Yertis

Original Poster:

18,082 posts

267 months

Saturday 7th March 2015
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Would this work on transparent pieces or would it make them go milky?

Yertis

Original Poster:

18,082 posts

267 months

Wednesday 11th March 2015
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I'll tell you this much – Audi spray-can paint is apparently impervious to brake fluid. It's not budged a bit. If no joy by Saturday I'll be whipping it out an trying something else.

Yertis

Original Poster:

18,082 posts

267 months

Friday 10th April 2015
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For various work related reasons the painted parts stayed in the bath of brake fluid for nearly a month so I wasn't hopeful of finding anything usable left in there at all. But amazingly (to someone not versed in chemistry) everything was fine, the paint washed off to reveal nice clean plastic with only minimal surface damage (from the solvent paint I was trying to remove) and no distortion, although maybe the polystyrene has gone a bit brittle. I'll post up some progress pics tomorrow. Time to buy a new compressor I think.

Yertis

Original Poster:

18,082 posts

267 months

Sunday 12th April 2015
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Here it is. Both A-pillars had cracked across and one of the B-pillars had come away completely. They're now cemented back into place – next job is to restore the surface and get some primer on.


Yertis

Original Poster:

18,082 posts

267 months

Monday 20th April 2015
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Whatever happened to "Liquid Poly 70"? The stuff I've just used smells like nail varnish remover and is quite viscous – I remember liquid cement being a very thin fluid and smelling quite different. Is Mek-Pak and better? (I'm putting in an order to Slaters for some plastikard, to improve the interior.)

Yertis

Original Poster:

18,082 posts

267 months

Thursday 23rd April 2015
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So I got the white primer on and now it's back in the brake fluid reservoir. That Halfords white primer is crap. Next time I'll listen to my own advice and only put on paint with an airbrush.

If the brake fluid doesn't touch the acrylic paint then this one is going in the bin.

Yertis

Original Poster:

18,082 posts

267 months

Thursday 23rd April 2015
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I've been musing on this at work today and have concluded that life is too short to faff around with this all over again. Putting it down to experience and fetching another one over from hlj.com.

Yertis

Original Poster:

18,082 posts

267 months

Tuesday 28th April 2015
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Having made the decision to bin it, but not being one to give up easily, I chucked it back in the brake fluid and went away for the weekend. Got back to find the "primer" had softened somewhat so after a half hours scrubbing with a toothbrush I'm now back where I was, so I'm now off to buy a decent compressor.

Yertis

Original Poster:

18,082 posts

267 months

Friday 1st May 2015
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Red Firecracker said:
Try and get one with a storage tank, and definitely a water trap. I've downsized (or more accurately, started using again after the bog compressor broke) to one of these now;

Yes, that's exactly what I'll be going for. The one I've had since student days was a diaphragm type with a water trap, which was fine for retouching and artwork but did/does have a very slight pulse to the spray.

Yertis

Original Poster:

18,082 posts

267 months

Thursday 16th July 2015
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Well this project is back in motion again, and I'll post up some pics later on. Quick question though – and I've googled around on this – does any one know whether Humbrol Clear needs to be diluted before spraying? It looks slightly syrupy to me but from memory thinning varnish makes it go matt – I appreciate this is based on experience with the old spirit/oil based varnish I was using when I last played this game in about 1980.

Yertis

Original Poster:

18,082 posts

267 months

Thursday 16th July 2015
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Thanks dr. I just found a youtube vid by Humbrol which says it can be airbrushed straight from the bottle, but I'll definitely be giving it a test first, not least because results over some paints (I've used Vallejo acrylics) are, according to "forum-lore", unpredictable.

As an aside it's lovely having an excuse to use the old airbrush again – I think I'm going to stick with the Aerographs because I know their every foible.