How much lacquer do you use? - created 07-10-2006

Gleason, Eric - 07/10/2006.16:56:26

I'm just about finished with my clear coats and realizing that I'm burning through lacquer pretty quickly. I'm using an HVLP gun and using between 2 and 3 ounces of thinned lacquer in each coat. Someone on another forum claims to get about 4 complete guitars out of a quart of lacquer.

The gun appears to be set up properly as the lacquer is being atomized very well at 20 psi (which is what the gun's instructions say to use). Each coat is about 2 passes, sometimes 3, and they appear to be fairly wet but far from the point that the lacquer will start to run. I'm using Behlen's lacquer, thinned 3 to 1.

If about 10 coats are necessary for the clear coats, I'm using at least 20 ounces just for the clear, plus some for the color coats.

Is this typical? Is there something I could be doing wrong?

How much you need on the surface depends a lot on how fine your wood preperation is. A dead smooth, fine sanded and pore-filled surface needs little finish. A rougher one, with lumps and bumps(even the ones you can't see) requires much more finish.

2-3 guits per gallon typically. That's McFaddens, pretty much straight from the can and thinned only about 20% at most.

Mike, I am so relieved to hear you say you use that much! I hope that's a typical amount so I can stop beating my head against a wall about how much lacquer I'm using.

FYI, someone on another forum (who seemed to have a reliable source for this information) posted that Behlen is McFadden's retail brand and that it's the same stuff.

Behlen is McFadden's retail brand and that it's the same stuff.

Ha!

Thanks, I needed a giggle today...

Behlen is Mohawk's retail brand(or perhaps the other way around).

McFadden's is McFadden's, and is only available directly, or through a few specific re-sellers.

Mike, 2-3 per gallon? You spraying in the wind or into a big fan(sucking most of the lacquer away from the surface before it can get to it)? Honestly, I could get 2 per quart, usually, Behlen's or McFadden's, for that matter(I've used both).

Whoops! I was wrong, and the guy did say Mohawk!

Mario, can I ask you to help try to shed some light on how Mike and I are using too much lacquer? I believe I have my gun set up well and am spraying fairly lightly, but still using at least 2 ounces per coat for both the body and neck (not each, for both).

I'm using the instructions at this site to make sure the gun is set right and atomizing well:

http://www.hotrodders.com/kb/body-exterior/articles/spraygun.html

1-1/2 to 2oz per coat is about right. How much of that is laying down on the guitar? And how many coats are you putting on? 6 was enough for me with lacquer, and quite often, 4-5 would suffice.

6 coats, really? All the guys at Guitar ReRanch say 10-12 coats. I had what I thought was a pretty thick coat on before, but I still got some sand-throughs when wet sanding.

How did you tell when you had enough clear on?

It's hard to learn to spray the finish on heavier in the places where you know there'll be sand-throughs. Edges...do them first, then fill in the middle. Too much air pressure wastes finish, and it makes it harder to lay the finish on the edges.

Heck I'd tell people to use 12 coats too if I sold the stuff.

The better you get at surface prep and pore filling, the less likely you'll cut through. that said, I cut through about 50% of the time, still, but that's because I'm quite anal about keeping my finish thin. The last guitar top I measured(I measured a chip of finish taken when clearing the area under the bridge) came out at .0015". That is one and a half thousanths.

6 coats of nitro would leave me at around .002-.003 most of the time.

And as Mark says, shoot a little more at the edges.

When you've done enough of them, you'll soon see if you're cutting through at the same area each time. If so, study -why- that is happening. If you're always cutting through at various places, look at your final surface prep, or look at adding coats.

Yes, 10-12 will gar-an-tee a great looking finish, but it uses up lots of lacquer, takes lots of time, and kills tone(on acoustic instruments). But it looks great, even for the first timers.

Mario most of my guitars are fairly big (Weissenborn style) and resonators so I'm not worried about a super-thin finish. I tend to do 9-12 fairly thin coats and sand about 2/3rds of that off.

Thinking about it I probably underestimated how many I get from a gallon, but at only 2-4 guitars a year it's hard to keep track. I just did 2 electrics and started with about 3/4 of a gallon. I still have about 1/3 or a little more left so maybe 4 is more accurate. I spray outdoors and just started using a decent HVLP. The guns I used before tended to waste a lot.

Also - lacquer sold in spray cans has lower solids content, so more coats would be needed for the same finish thickness. And that commercial site is largely selling to inexperienced finishers, so a little "buffer" (ha) in the thickness is probably a good idea. I'm not surprised at the 8-12 coat recommendation.

I think I usually do 10-12 coats.

David, how much lacquer do you use in 10-12 coats?

Eric, it's been a while since I finished an instrument! I'm just getting back into building after a long hiatus. I was using catalyzed lacquer which I bought in gallon cans... so I'd mix up a batch in the spay gun cup. I may have used two cups worth... but I'm guessing as I don't remember clearly. Of course it also depends how mow you spray and how much you thin your finish.

My friend John Gagliano would be able to answer this... he's a wiz at spraying... he probably sprayed most of our instruments anyway... let me give him a shout out.