Thin lacquer coats

The Achilles' Heel of Luthiery
Post Reply
Stray Feathers
Posts: 699
Joined: Sun Sep 08, 2013 11:39 pm
Location: Ladysmith, BC

Thin lacquer coats

Post by Stray Feathers »

I've had issues in the past trying to get enough lacquer on, based on recommended .008 - .010". I've just finished spraying two guitars and two ukuleles, and finally got to .009", but it took 19 coats to do that. I'm assuming I'm spraying thin coats, but I am not getting any sandy spots, and yet I do have some runs and curtains, so I am reluctant to try to apply it more heavily. I did calculate that I am using about 4 oz. for one coat on one guitar, of 75-25 mix, so 3 oz. of lacquer.I'll continue this way until I get more experience I guess, but, as Doc Watson sang, " . . .it gets teejus, don't it . . ." Bruce W.
phavriluk
Posts: 573
Joined: Mon Jul 09, 2012 9:49 pm

Re: Thin lacquer coats

Post by phavriluk »

Here we become separated by a common language....I'm a simpleminded sort and what I've done is applied a cross-coat (cover in one direction, second wet cover 90 degrees away, it helps to minimize 'stripes'). Let it dry enough to scrape, do it again. And again. And again. Block sand to suit. Minimum buildup, thorough coverage. Stop when there's n o more shiny spots after scraping.

I've found this ain't like painting cars, I can't throw on a bunch of lacquer and then sand it once at the end. But I get very little buildup and I stop when I run out of need for more finish.
peter havriluk
tippie53
Posts: 7027
Joined: Fri Mar 03, 2006 7:09 pm
Location: Hegins, Pa
Contact:

Re: Thin lacquer coats

Post by tippie53 »

what are you using ? gun? can?
you know I have videos on this ?
https://www.youtube.com/results?search_ ... eek+finish
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
Stray Feathers
Posts: 699
Joined: Sun Sep 08, 2013 11:39 pm
Location: Ladysmith, BC

Re: Thin lacquer coats

Post by Stray Feathers »

John, I am using (as it happens) I think similar equipment to yours: Fuji Mini Mite 3 turbine, GXPC gun, 1.0 mm spray cap. I've followed procedures you shared in numerous posts here on the forum. I use thin cardboard test patches, which I double-sided tape to the bridge masking (measure cardboard before spraying, then at intervals). My results look very similar to what you show in your video, so I feel like I am doing it right - it just takes me a lot more coats to get there. What I have not done is accurately measured the top thickness before and after all spraying, to see if that reads differently (next time). I think I've used about 57 oz. of lacquer per guitar, so just over 2 guitars per US gallon, and the lengthy lacquer finishing guide by LMII says a gallon should do "3+" guitars. So I seem to be using more. I am careful with overspray but maybe there is still too much; my spray pattern may be a little bigger than yours (you say "fist size?) Bruce W.
tippie53
Posts: 7027
Joined: Fri Mar 03, 2006 7:09 pm
Location: Hegins, Pa
Contact:

Re: Thin lacquer coats

Post by tippie53 »

yes you are using way too much
feel free to call me
To help next time
place some tape at the fretboard extesnion and a business card at the sound hole. I use foam rubber and a deli cup then you can measure before and after spraying. I do a guitar on about 8 to 10 oz of finish
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
Stray Feathers
Posts: 699
Joined: Sun Sep 08, 2013 11:39 pm
Location: Ladysmith, BC

Re: Thin lacquer coats

Post by Stray Feathers »

John, thanks for your input on quantity - I'll have to figure that out. But I am doing as you suggest, with small cards on the area masked for the bridge:
You do not have the required permissions to view the files attached to this post.
tippie53
Posts: 7027
Joined: Fri Mar 03, 2006 7:09 pm
Location: Hegins, Pa
Contact:

Re: Thin lacquer coats

Post by tippie53 »

good
you should have more coverage that you are stating call me if you need to
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
Post Reply