Devilbiss finishline pressure question

[Mutz]

Hi, ive never sprayed before; but decided to give it a go.

Problem i have is i have a devilbiss finish line gravity spray gun Think it is the first one. only has 2 adjusters at rear and 1 under air input. top adjuster is fluid, 1 under that is trigger/needle and the one at the bottom appears to be air in.

Now i was told it should give a nice finish with cellulose, but i find it pulsates and leaves a uneven surface.

It has a 1.6 needle setup which im told is correct for celly, im running it at between 45-50 psi, is this the problem, what pressure should it be?

Must be some sprayers on here some where.

[Mutz]

Right ive found a manual and pressure is right!!

Hmmm, just found a thread on another site says should thin 30/70 on last coat, is that correct? (Paint/Thinners) not 50/50 as the other coats ive done? as this will give it a good gloss finish!

[Range Rover Blues]

Yes. My mate taught me to put a mist coat on first, so that the thinners of the second coat has somewhere to go, then finish with a thinner last coat for a better shine.  I've read that some restorers put 7 or 8 coats on, but that's too much paint or too thin to run out properly.
The bottom adjuster, leave it fully open for now.  Trying to remember what the other 2 do, one is the paint flow IIRC and the other is the nedle stop, that control how far you can retract the needle which in turn controls how much pain t comes out of the gun.

[Mutz]

Think i need a service kit as im getting air blowing back into paint canister!!!

Might give up on DeVilbiss, and buy another gun.

Thanks for info RRB.

All these hints help

[Range Rover Blues]

Is it an old gun then?  obviously a gravity feed doens't have a pressurised can, have you stripped and cleaend it? they need thorough cleaning but IIRC the gland which seals the needle is adjustable :-k

I'd be able to tell better is I could see it.

[Mutz]

It is quite old, it has been completley stripped and cleaned, i have adjusted the nut for the rear needle seal just off the point of needle not returning.

But on looking at parts diagram i might be a fluid tip seal missing, as i cant locate it on the gun at all!!!


Its the FLG-611.

Am thinking about getting a Sealey gravity gun, as reasonable price, under £23 on the bay; any thoughts RRB?

The Sealey would be cheaper than getting the parts for the DeVilbiss!!

I will try and email you the PDF manual of the gun.

[Range Rover Blues]

Devilbiss are not cheap to fix, the fact that you can buy a new gun for less than the spares should tell you something about the quality though.

The Sealey one is ok, it won't last as long, it probably won't give you as good a spray pattern as a Devillbiss in good nick, but for what you want to do and for a gun to learn with I think it might be ok.

For £23 you might as well give it a try.

[Mutz]

well its only got to do one 90, so think i will get it anyway.

I will get the repair kit for the Devilbiss, but just want to get on with spraying the bits ive got ready.

Good thing is im spraying the panels before putting them back on, so only small sections at a time.

[Range Rover Blues]

If you spray metallic paint then there's a good chance the differnet panels won't match, all you can do is try.  The metallic flakes lie differnelty andthis effects the way they reflect light.

Try to adopt a consistant technique, like always spray left/right not up/down.

[Mutz]

Not metalic, just plain colour; realised metalic wouldnt be an easy option for a first time spray.

Also plain colour easier to repair when off road damaged.

[Range Rover Blues]

Very true!

Top tip, with a gravity feed gun, empty the bwol after every coat, remix/stir it and add back to the gun just before spraying the next coat.  I clean my gun between coats now too.

If you don't you might get a splodgy/thick bit of piant for the fist second.

[Mutz]

Taken on board, thanks.

[Range Rover Blues]

Got your email BTW, when I've time I'll have a look and maybe ask my mate for advice ;)