Nozzle size - what’s it all about?

[rtfoe]

There you have it Max...it's not rocket science so knock yourself out. :tongue-out3:

Cheers,
Richard

[Guest]

Ah Steve, I like the way you tell it as it is! Reading on the lines, as well as in between them, has been most instructive; liking your work!
I’m just having a break from trying to clear some work space to make a start, but it’s worse than I thought!! I’ve got two sackfuls of stuff and there’ll be another couple yet I reckon! It’s years of ‘bits and pieces’, you know, the the sort of stuff that’ll ‘come in handy even if I never use it!’ But, on the bright side, I’ve found some handy small artists brushes along with oil and acrylic paints I’d forgotten I had! Back to the grind after a coffee and cake; I have to keep my strength up!

[Guest]

While taking my break I just found this pic, on eBay of all places. For those who don’t recognise it (and I suspect that won’t be many) it’s an SE5a. It happens to be the best I’ve found so far. Thought I’d share.
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[Guest]

Well, I’m on the verge! Sufficient space now made, my new cutting mat put down and my compressor connected for the first time. I first had to cut the moulded on plug off, because it wouldn’t go through the plug hole on my bench! My first half panic came when I couldn’t work out which way the adjuster moved to reduce pressure, but having remembered that stillp Peter had given me a manual link, I checked and found that it’s counter intuitive, and indeed counter clockwise, to reduce the pressure! So having checked that the auto tank pressure cutout works, and that when I press the trigger, air comes out, I decided I’d leave the inaugural spray until tomorrow. The excitement is almost palpable!

[stillp]

:thumb2:

[yak face]

No worries.

The 'over thinking' also puts people off. The thinning of paint is not absolutely critical. I used to be a chemist, I know what exact measurement means, and thinning paint for spraying it definitely is not!

You just need to experiment to find a consistency which will give the coverage you want, and pass through your brush freely. In my experience almost every pot or tin of paint is different, so giving ratios is pointless. Experimentation and experience are the only way to get it right most of the time. I do it by eye and the look of the paint in the cup. At the risk of sounding like a smarty-pants, I honestly don't remember the last time I got it far enough off to cause any problem

Don't be afraid to up the pressure you spray at. I was originally, many years ago, given some lessons by an airbrush artist rather than model maker and that is where I learned to spray at the relatively high pressures I use. Many airbrushes won't even work properly at the pressures I see touted about on some modelling forums!

Once you find the magic formula for the consistency of the medium you are spraying and the pressure you spray at, stick with it. There is no need ever to alter it and potentially provoke all sorts of issues. I continually see people advocating extra thinning and ridiculously low pressures to spray Luftwaffe mottle for example. Bollocks! I've been spraying it for years in exactly the same way as I spray everything else.

The acres of camouflage on the 1/24 Spitfire float plane were sprayed in EXACTLY the same was as the squiggle on this little Ba 349 Natter.

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Good luck and have fun. After the initial learning curve you will find that airbrushing is not a dark art, in fact it is a doddle and great fun.

Cheers

Steve

Couldnt agree more Steve! i personally use the same methods as you , spraying at anything from 30-40 psi and not worrying about exact ratios. As you say , heavy thinning and spraying at mega low pressures just doesnt work for me and can cause all sorts of problems . My view is if you want a faint line or gentle mottle etc then dont press the trigger too hard and dont pull it back too far , these airbrushes are infinitely adjustable so its just a case of practising . above all though do what works for you and dont be fooled into thinking that theres only one way to do it, cheers tony

[Guest]

Okay, finally had a play. It was a mixed morning, probably because I started out with a couple of old Thayer and Chandler brushes I bought years ago but never got around to using. They are both side feed brushes and there were problems with both. But, I learned something none the less, and that was you have to pull as well as push!
Connecting up the brand new Chinese cheapy, I first put some water through it and, satisfied that it worked okay, I then put in a mix I’d made a day or two earlier. This was a well thinned (with distilled water) Windsor and Newton acrylic. I’m aware that this was a bit risky, but I had it to hand and went for it. It worked! I now played around with different pressures and distances before being called for tiffin. I had a quick clean up by tipping out the mixture, wiping out the bowl, blowing through some distilled water, and then repeating this sequence a couple more times before disconnecting the brush and taking it through to the bathroom where I removed the tip and gently used an old toothbrush to clean the nozzle and needle. I also had a scrub inside the bowl, but at this point realised I didn’t have anything to get into the ‘well’ (I’ve got small brushes coming). I’ve left a little water in the bowl and will check it out further tomorrow. Unfortunately I’ve been otherwise engaged this afternoon, and I’m hoping it can wait. The next major thing I learned was that the acrylic smells awful (well at least my ‘mixture’ did)! So this, I think, confirmed that painting is going to have to be confined to my workshop, particularly as I’ll be using enamels. I also realised that even this very short session should have been conducted with a mask on. A little more patience would have seen me wait for my new booth and mask:sad::sad:.
The story continues. I may start a new thread.

[Dave Ward]

Max,
cotton buds! Essential part of the tool set, cleaning, applying, removing. Imagination the only limitation. Get a big tub from Pound shops/Tesco really cheap
Dave

[Guest]

Max,
cotton buds! Essential part of the tool set, cleaning, applying, removing. Imagination the only limitation. Get a big tub from Pound shops/Tesco really cheap
Dave

Thanks Dave! I’ve got loads of ‘em, just totally forgot. As from now they’re on the bench!
Cheers
Max

[Mr Bowcat]

Max, IPA (isopropyl alcohol) is your friend for cleaning airbrushes. I get mine by the gallon from https://darrantchemicals.co.uk/isopropyl-alcohol.

I tend to blow through a cup of IPA then put the whole brush in a container (plastic take away type) with enough IPA to cover it. I just leave it in there until next use and just blow some tap water through before I add paint.

Edited to add: And interdental brushes are good for getting stubborn deposits out of nozzles.

[stillp]

Does IPA work with enamels Bob?

Pete

[Mr Bowcat]

I'm not to sure Pete, I use acrylics. I have used it to clean car primer which is pretty tough stuff, so it might work with enamels??

[Guest]

Max, IPA (isopropyl alcohol) is your friend for cleaning airbrushes. I get mine by the gallon from https://darrantchemicals.co.uk/isopropyl-alcohol.

I tend to blow through a cup of IPA then put the whole brush in a container (plastic take away type) with enough IPA to cover it. I just leave it in there until next use and just blow some tap water through before I add paint.

Edited to add: And interdental brushes are good for getting stubborn deposits out of nozzles.

Hi Bob thanks for that, I’ve got a can of IPA that I use for lens cleaning. So I know that it acts as a degreaser, and evaporates quickly, but what does it do to acrylic?

[Mr Bowcat]

Having just had already up it looks like IPA will work on enamels, but maybe not as well as other products. Have to admit I missed the part in your earlier post when you said you were using enamels. Doh!

It will clean acrylics straight out, no problem. Plus less nasty fumes with acrylics. I spray in the house (with a spray booth) so anything too pungent is a definite no for me.

[Guest]

Having just had already up it looks like IPA will work on enamels, but maybe not as well as other products. Have to admit I missed the part in your earlier post when you said you were using enamels. Doh!

It will clean acrylics straight out, no problem. Plus less nasty fumes with acrylics. I spray in the house (with a spray booth) so anything too pungent is a definite no for me. :smiling3:

Yeah, the first mistake I made was not realising that the Gunze Mr Colors were ‘solvent based’ which I’m assuming are enamels?