What's gone wrong now?

[Andy T]

No, not really.

As an alternative to MRP, Mr Color and S M S both do some gloss colours in their ranges and are available in the shop, but to be honest the Tamiya ones you have should be just fine when thinned with a good lacquer thinner, you just seem to have got a rogue one.

[Gern]

Done some hexperimenting as suggested by you good folks.

I bought a new jar of Tamiya gloss red and mixed up two batches in cheapo shot glasses. One thinned with MLT and the other with X-20A - both 50/50 as near as I could measure.

I sprayed each mix using both my Infinity CR+ and my Ultra - both with 0.4mm needles and set at 15psi from about 4-5 inches.

All four tests came out nice and smooth and glossy as they should be, although it seems the coverage from my Ultra was marginally better.

I have to conclude that the issues I had must be down to the old paint I used. I don't know if it was just old paint or if it had been mixed/contaminated with the wrong thinners or something.

Now all I got to do is sort out my compressor - starting with regular emptying.

The jury is still out on swapping to MRP, but big thanks to everyone for your help and advice. Onwards and upwards! :smiling:

[Tim Marlow]

Done some hexperimenting as suggested by you good folks.

I bought a new jar of Tamiya gloss red and mixed up two batches in cheapo shot glasses. One thinned with MLT and the other with X-20A - both 50/50 as near as I could measure.

I sprayed each mix using both my Infinity CR+ and my Ultra - both with 0.4mm needles and set at 15psi from about 4-5 inches.

All four tests came out nice and smooth and glossy as they should be, although it seems the coverage from my Ultra was marginally better.

I have to conclude that the issues I had must be down to the old paint I used. I don't know if it was just old paint or if it had been mixed/contaminated with the wrong thinners or something.

Now all I got to do is sort out my compressor - starting with regular emptying.

The jury is still out on swapping to MRP, but big thanks to everyone for your help and advice. Onwards and upwards! :smiling:

Great news Dave. I did a mini in Tamiya Red a few years ago and it came out really well. I found that if I left the paint a week or two to really harden off it could be polished with Tamiya’s finishing compound, coming out with an excellent surface finish that looked real.

[Andy T]

A rocky road but you must be pleased to find out it wasn't you or your tools at fault.

[Gern]

A rocky road but you must be pleased to find out it wasn't you or your tools at fault.

Too right Andy 'cos it's usually me that's b******d things up!

[Gern]

Been having a thunk about all that rust in my compressor tank. Haven't I seen something about compressor tanks with rustproof chrome interiors or am I dreaming?

[Tim Marlow]

Been having a thunk about all that rust in my compressor tank. Haven't I seen something about compressor tanks with rustproof chrome interiors or am I dreaming?

Possibly dreaming Dave. Never seen chrome on a car or motorbike that didn’t rust if you left it unpolished. I’d assume a tank interior would be the same. For rust free I’d go for a stainless steel tank if you could get one, and even that would probably exhibit rouge after a time. I know the stainless kit we used In pharmaceutical production suffered from that all the time.

[Gern]

Possibly dreaming Dave. Never seen chrome on a car or motorbike that didn’t rust if you left it unpolished. I’d assume a tank interior would be the same. For rust free I’d go for a stainless steel tank if you could get one, and even that would probably exhibit rouge after a time. I know the stainless kit we used In pharmaceutical production suffered from that all the time.

So stick to what I've got (with regular emptying) 'til it falls apart then get another?

[Tim Marlow]

So stick to what I've got (with regular emptying) 'til it falls apart then get another?

Sounds good, but keep an eye on the tank for bulges when it’s pressurised. Once it bulges under pressure I’d change it. Splitting under pressure will make you jump if nothing else…..

[stillp]

I'd have thought it's more likely to become porous due to rusting, so it won't pressurise.
Pete

[Tim Marlow]

I’ve seen stainless steel vessels both bulge and become porous as they fail Pete. Bulging is far more common in stainless pressure kit, but you might be right about mild steel becoming porous first. Visible bulging is what the insurance inspectors used to look for before passing the tank for another years use.

[Waspie]

I'd have thought it's more likely to become porous due to rusting, so it won't pressurise.
Pete

That should be the nice thing about Chrome, it isn't porous!! (Good chrome that is). In aviation they use a posh chroming technique called fescallising, (spelt phonetically because I don't know it's correct spelling!! Fescallising is used in undercarriage/shock absorbers!! (The shiny bit!!)

[Tim Marlow]

This has taken a bit of a surreal turn. I can find loads of references to Fescalised metal……but they are all based on the same text and none of them say what it is, or what is actually done to make it……I assume it’s some sort of hardening and polishing process, but is known under another name. As an aside, we used to use Electropolishing after which stainless steel looks exactly like chrome plating. Chrome plating shouldn’t in itself be porous, but it’s only a few microns thick so doesn’t cover that well.