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Got a few sand throughs on my latest guitar,nitro and thinking an airbrush would be the answer, reccomendations please.

One word: NO. An airbrush wouldn't move enough volume of material. Consider a Preval sprayer to spot-spray what's in the gun. Or brush it on, and it doesn't need as much thinning as spraying.

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Peter Havriluk

Perhaps a tape off… then one of the spray cans ? Level sand and buff?


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What finish is it?

nitro

This little spray gun will handle sand throughs and spot repairs and won't break the bank:
https://www.harborfreight.com/air-tools ... 92126.html
Adding a regulator at the gun can help you dial things in:
https://www.harborfreight.com/125-psi-a ... 62695.html

I like to use the Stew Mac rattle cans for nitro touch ups.

That’s what I do too.

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Steve Smith
"Music is what feelings sound like"

I’ve used an airbrush for this type of thing before and it works fine from my point of view.

I've used an airbrush successfully for touch-ups on nitro. It takes a bit of getting used to, as the lacquer tends to dry before it hits the target, so a very deft hand is required to get the amount you want exactly where you want it. You may be better off with the small spray gun that Clay suggested, if it behaves more like a normal gun, but I've not tried one.

However, if you have "a few sand-throughs" you're probably better off respraying the whole guitar.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

After trying several airbrushes, I found one I really like. It is the Iwata Eclipse HP-CS. It sprays lacquers and other finishes (including waterbase) wonderfully.
It's well made and not cheap. Great for sand-throughs and spot spraying. Go to their website and look at the specs they give you. Great info.

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Formerly know as Mandodiddle.

As is clear from the replies there are different ways to do this.

Unless you are well set up for spraying it does make sense to use rattle cans. Last time I used masking so the spray went where it should. Razor blade scraping and some careful sanding. Then as Trevor suggests an overall respray to tie it all in.

Gosh it is annoying though when you thought you’d got it just right!

Dave

No on the air brush As mentioned above you have to rebuild the lost finish. I use a touch up gun for this and apply about 4 yo 6 coats I don't bother masking off you can level sand this later .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I have several Pasche air brushes and an assortment of tips that spray lacquer very well.

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wah
Wah-wah-wah-wah
Wah

I'm dealing right now with sand-thrus that reveal themselves as high spots while block-sanding. My problem isn't applying finish to the bald spots but building up the surrounding area to allow some coverage on the former high spots. I agree with the advice to use a small spray gun. Airbrushes are artists' tools, and what I need is some means to get a large amount of finish laid down, exactly what an airbrush won't do.

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Peter Havriluk

If the wood itself is creating a "high spot" you may be better off sanding it down and feathering it out with the rest of the wood and then refinishing a larger area. Trying to build enough finish material up and over a high spot in the wood and then leveling the finish is difficult (sometimes impossible) to do unless you are doing an extremely thick finish (think - epoxy encapsulated live edge tables).

The more 'rinse and repeat' coating cycles I apply, the more reason I find to continue. I feel I'm auditioning for Sisyphus' job. And all that sanding keeps the finish thin, except for the low spots. Bur each cycle shows smaller low spots.

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Peter Havriluk

One other thing to keep in mind - some finishes are prone to eventually check and crack when too thick. DAMHIKT
A few small thick spots will -probably- be O.K., but as you say it does feel like rolling that stone up hill.

Any of the quality HVLP guns - either turbine or conversion - should be able to be dialed back such that they may be used for spot work... I've been using one of the guy's old 3-stage turbines and a spare T75G for touch-ups...just roll the fan back to round, dial down the airflow, and tweak the material knob to give a very controlled area of application. Harbor Freight sells a jamb gun and a $10-on-sale HVLP gun (#62300) that can be dialed back to shoot thinned lacquer for touch-up work. Both need to be well-cleaned prior to use, but are very adequate for lacquer work and have lower CFM requirements than one might assume.

If the sand-through goes through the sealer used, you may have to reseal to prevent a dark or light spot

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For the times they are a changin'

- Bob Dylan

^^^^^^^^^^^^^
What Woodie said.

Its pretty cool just how much the Fuji T75G can be dialed back for touch ups, which I’ve done.
I’d use the Fuji before my my Sata Minijet (which is pretty much collecting dust).