Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Painting, Finishing and Care. => Topic started by: justboatonic on June 29, 2019, 01:22:43 pm

Title: Airbrushing tips.
Post by: justboatonic on June 29, 2019, 01:22:43 pm
Im biting the bullet and started to airbrush the new parts Im building for my HMS Newcastle. Ive watched more than a few YT vids to get tips about thinning the paint (Tamiya acrylic),ensuring full movement of the dual action airbrush trigger and suitable air pressure (20 - 22psi) etc.

We are not talking huge parts here, it's 1\72 scale and talking parts like Scot Domes cabin, cabin that sits behind the funnel and other small parts. Frankly, Im disappointed with the results  {:-{
I wasnt expecting rattle can coverage from the off but I cant seem to get a spray fan more than about 5mm wide. If I hold the airbrush about 5" from the part, hardly any paint seems to land on it and I get very light coverage. Nearer and I get a line about 5mm tall.
I bought the gun and compressor from an airbrush supplier and discussed with them my needs. They said the unbranded airbrush would be suitable for what I needed ie ship hull and parts spraying. I guess the fact the brush is unbranded speaks volumes!?
So, any ideas or tips?
TIA


Title: Re: Airbrushing tips.
Post by: dougal99 on June 29, 2019, 03:18:08 pm
From my limited experience, it would appear your brush has a fine tip meant for close up, very fine work. I have 2 basic badger brushes with different size tips; with the fine tip I get the same sort of results as you. I also have a better quality single action brush on which I can control the spray with a screw adjustment. I haven't ventured into double action brushes yet (one is sitting in its box in the workshop) so I don't know if you can adjust the flow other than by the trigger. You may need to obtain another tip.
Title: Re: Airbrushing tips.
Post by: deadbeat on June 29, 2019, 04:00:23 pm
I use unbranded cheap airbrushes and are ok for my needs. I have a compressor with a 3l tank, essential for good results, on-demand compressors are difficult to use i found. I usually use a 0.3mm needle at 20psi. I use nothing but Tamiya acrylics with an airbrush, mainly for ease of cleaning the airbrush, I have not had good results with Humbrol acrylics. The most important issue is thinning the paint to the ideal consistance, I use tamiya thinners; it does take a while to get the right feel of dilution, something akin to semi or skimmed milk. There are some excellent tutorials on YT, but trial and error is the only way to learn.
I hope I'm not teaching you to suck eggs, but If your brush has a screw end in the handle this changes the length the trigger can be pulled back, the further back it travels the larger the spray area, also distance from workpiece will change the area covered. I still consider myself a beginner and have just sprayed the camo on my 1/35 AS90 howitzer and I was very happy the the precision I got by going in close and restricting the movement of the trigger.

For much larger areas I would used rattle cans, Tamiya has a good but limited range.
Title: Re: Airbrushing tips.
Post by: Andyn on June 29, 2019, 06:16:05 pm
5mm at 5" away is nothing to do with your nozzle or needle, even the smallest nozzles will do up to around an inch spray pattern (the 0.18mm nozzle in my CM-SB still sprays up to 20mm)


Sounds like your paint is clogging, and from experience 22psi is way too high for anything. I'm spraying at 12psi for Hataka, Vallejo paints and alclad. That high a pressure will completely atomise your paint before it hits the model, especially given how hot it is currently. All you'll end up painting is fur, and at 5" with any airbrush you're mostly painting the air around you anyway


What is your paint mix- how much thinner are you using and are you using flow improver?
Title: Re: Airbrushing tips.
Post by: Howard on June 29, 2019, 06:53:32 pm
Hi Tia,
As has already been said I would never go above 18 psi and normally much lower, you can lean a lot from reading model railway painting plus weathering books as for thinning if not using Tamiya paint and acrylics and there thinners I often use Halfords screen wash as a thinner for other acrylics never use water.
         Regards Howard   
Title: Re: Airbrushing tips.
Post by: jonggd on June 29, 2019, 07:30:16 pm
Hello Tia, Like you am building a T42 in 1/72 scale, and have had the same issue with airbrush coverage. I purchased a trigger action airbrush with a 0.5 mm needle/nozzle and this is much better for spraying larger areas. Jon
Title: Re: Airbrushing tips.
Post by: RST on June 29, 2019, 07:53:01 pm
Was it like the eBay / expo tools airbrush kits?  I started with one, compressor is great but airbrush was pap.  Soon as I changed to an iwata neo the difference was night and day.  I only spray the tamiya acrylics and use their thinner. The Chinese airbrush had a smaller needle than the neo which is 0.3mm if I recall. Just couldn't get any paint through with the finer needles. Tamiya sprays perfect since. The cheap airbrushes are cheap for a reason IMO.
Title: Re: Airbrushing tips.
Post by: justboatonic on June 30, 2019, 06:13:31 pm
5mm at 5" away is nothing to do with your nozzle or needle, even the smallest nozzles will do up to around an inch spray pattern (the 0.18mm nozzle in my CM-SB still sprays up to 20mm)


Sounds like your paint is clogging, and from experience 22psi is way too high for anything. I'm spraying at 12psi for Hataka, Vallejo paints and alclad. That high a pressure will completely atomise your paint before it hits the model, especially given how hot it is currently. All you'll end up painting is fur, and at 5" with any airbrush you're mostly painting the air around you anyway


What is your paint mix- how much thinner are you using and are you using flow improver?
Hi. Interesting comment about pressure because all the vids Ive seen suggest 20-22lbs. I'll see about turning the pressure down.
Also, you say about paint clgging in the airbrush. I noticed when I was cleaning the brush last night after running some cleaner and some bottled water through the airbrush two things. One, I could see a definite 'fan' spray and two, when held against some paper, this fan was quite large and more in line to what I was expecting with the paint.
As mentioned, Im using Tamiya XF and Ive tried to thin to the consistency of milk. Must admit what looks like the consistency of milk might not be! Maybe the plain water run through the brush is an indication the paint is still a little too thick?
Title: Re: Airbrushing tips.
Post by: Stan on June 30, 2019, 07:50:33 pm
Hi I have included just a few picture to show the results you can get when airbrushing your models. I have never had much success with non branded units. If this is your first steps into using this method of painting your models then a single action airbrush will be fine. Dual action guns need time to get to grips with but that's your choice.

Stan. :-)) :-)) :-)) :-)) :-)) :-))
Title: Re: Airbrushing tips.
Post by: justboatonic on July 02, 2019, 06:08:07 pm
Thanks Stan. Lovely boat and finish! Sorry I missed your pm's but have now sent an acknowledgement.
Title: Re: Airbrushing tips.
Post by: Stan on July 02, 2019, 08:45:13 pm
No problem I hope your venture into spraying your models goes alright.
 :-)) :-)) :-)) :-)) :-)) :-)) :-))

Stan