Which spray gun?

Can anyone suggest what size and type of gun would be suitable to paint a 5" gauge locomotive? I am thinking gravity feed touch up size of gun, and conventional, not HPLV, as my compressor is small, but this is guessing and advice would be appreciated, including nozzle sizes.

You don't say what type/size compressor you have, but a touch up gun with a 0.8mm nozzle would be about right.

That type of gun would give paint delivery not so different to an aerosol but in a flat pattern not conical.

Most general use body shop guns are 1.2 or larger. these will deliver to much paint unless used with great care. On an engine which has lots of nooks and crannies a smaller gun will allow for a little more build up in the corners without leaving runs all over.

Saying that, smaller parts you intend to spray you could use an air brush with a 0.5 nozzle and get a reasonable spray pattern and finish.

This is all very subjective and although I have done a small amount of paint spraying I am by no means an expert.

John

Edited By John Bromley on 22/11/2014 10:30:00

Edited By John Bromley on 22/11/2014 10:37:32

The best advice on painting a loco can be found in Chris Vine's book, "How (not) to paint a locomotive". There are some photos of his remarkably well finished loco here.

Russell.

I have a 2.5 HP 24 L tank compressor and I do have Chris' book. He went for an HVLP gun, pretty high end, I think.

Gravity feed is the right way to go. Go to a professional paint place and seek their advice. don't buy the cheapest and learn how to clean it before you use it.

They are not difficult to use but need a lot of learning to get it right.

Hi Simon

Another thing you have to think about is what paint you are going to use, the viscosity is very important I did paint spraying for 6yrs at a Ford main agents and used a suction DeVelbiss also high end, but I use a standard 1ltr gravity fed Draper and achieve good results. Very good advice by Al Learn how to clean it a lot of jobs can be spoilt by a part blockage or hard bit of paint being sprayed out.

Stan

Thanks for the replies. I'll also ask the member of our club with the best painted engines. I know he uses two-pack. Others use enamels, whatever that means these days.

Simon

Warning !

Two-pack paint includes various types of polyurethane, epoxy and acrylic systems, consisting of a base component, in combination with a hardener or catalyst. Quite a toxic concoction that can cause a series of health issues; therefore, two-pack paint is only to be applied by those people with appropriate knowledge and training.

Paul.

Simon

Take Pauls advice don't go down the Two-Pack road, you need air fed mask and full protective clothing to spray it, the hardener is Isocyanide the stuff that killed all those Indians when the Union Carbide plant exploded. Even with all the proper PPE we had to have hospital checks every 12months Cellulose used with paper mask is far safer and can still be bought in solid colours.

Stan

A hint on getting rid of orange peel.

Let the paint dry out, completely, then rub down using fine wet&dry, wet naturally, to get a nice smooth satin finish, taking care of edges of course.

Now the trick to bring it up all bright and shiny, is to use ordinary automotive polish on that smooth surface.

Couldn't believe the result when I first tried it on my Simplex.

Geoff - Still waiting for that heavy downpour.

What paint did you use on the Simplex though? I've been doing a bit of research on the net about automotive paints. I gather that acrylic enamel is probably the go, one-pack. It takes ages to harden up, so there would be no cutting back and polishing that. I have sprayed guitars I made with nitrocellulose. You simply build enough coat so it can be cut back flat and level and then polished with grades of polishing compounds. Tedious but easy. I gather lacquer is too soft for locos and not durable. What paint type is Phoenix, but the way? Not that it could be shipped to Australia due to hysterical safety obsession.

Simon

Your compressor is fine for a touch up gun there are loads of gravity fed 100 ml cup capacity on e bay for between £10 and £25

this one is just like mine

http://www.ebay.co.uk/itm/BERGEN-Mini-HVLP-Gravity-Feed-Spray-Gun-115ml-plastic-Cup-0-8mm-Nozzle-B8704/141470599076?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D28111%26meid%3D3683fb38b4b24ba595fd9d6ceb7ac486%26pid%3D100005%26prg%3D11472%26rk%3D1%26rkt%3D6%26sd%3D151168393547&rt=nc

it easily sprayed a 48" span Lancaster i made for the museum. I also used warbirds water based paints from Fighteraces and got excellent results. Light years ahead in terms of time, practicality and finish compared to trying to use an air brush.

Hope that helps

Regards Clive

Simon

Forget the enamel paints none of these can be wet and dried as the paint hardens from the outside and the inside remains soft for a long while, nitro cellulose dries through and can be wet flatted and re polished with compound or even metal polish, so if you are unlucky and get a run it can be rubbed out as for lacquer you can buy cellulose lacquer or blending clear.

Stan

Simon,

It was bog standard Humbrol, sprayed on with one of their cheap plastic guns.

As Stan mentions, it needs to be left for some time to dry out thoroughly and harden.

The time waiting didn't bother me as I was busy with the mechanical parts at the time.

A quicker drying solution though if in a hurry.

Geoff - Carport dripping with condensation