Official Luthiers Forum!

Does anyone know of any good books or video instructions on guitar finishing? This seems to be where I have the most issues. Currently I’m using a wiping varnish ( waterlox ) with marginal results. Haven’t ever tried laquer but thought about using the spray cans on the next build.

I've found Dan Erlewine's book to be pretty helpful. He focuses on more run of the mill finishes, and doesn't really get into any of the more advanced modern stuff.

https://www.stewmac.com/How-To/Books/Gu ... -Step.html

Another vote for Erlewine's book and all the great vids at StewMac. Robbie O'Brien also has some great video's - particularly pore filling options. I used rattle cans on my first several guitars 13 years ago, pretty much following Erlewine's schedule and they came out beautifully and have lasted very nicely.

Do you remember approximately how many cans were needed to finish the body? I was thinking of cans but I’m also not opposed to spending up to 500 on a hvlp rig.

One thing about the StewMac finishing book (which is excellent): It is geared for spray finishing, and not for hand applied finishes. That's where the OP is headed, so that's fine here. I just would not want folks to think the book covers all sorts of finishing methods; it clearly doesn't. But it is a great resource on a lot of topics that would be useful to all finishers.

Probably 5. That is one of the big problems with rattle cans - there is a lot of propellant and probably a lot of reducer for a give amount of lacquer. The coats go on thin and at least I didn't have as much control over the quality of each coat as I do with a spray gun - in other words there might be more orange peel or dryish areas that needed more level sanding. I know I put on somewhere around 20 or more coats with rattle cans - now its more like 12 to 15 with a gun.

For convenience it can't be beat and I keep a couple of cans of StewMac's lacquer for touch ups and small projects where I don't want to fool with the gun. Here are a couple of old pictures of my first guitar - the guitar actually looks better than my photography skills. And thats bear claw in the top, not scratches





My finishing has improved, I'm using some other products and methods, but I think that was pretty good for a newbie who knew nothing and just followed Dan's instructrions.

Don is correct, the book is primarily about spraying two different products - solvent and water born lacquers. He touches on many of the other finish options - oils and shellac but doesn't go into detail or really say much about them. These finishes are very popular with some builders - I'll be honest, I tried the popular gun stock oil on a couple of barn wood electric guitars and thought it was just fine, but the next time I worked with "good" wood I went back to my good old nitro. I have also tried several different water born lacquers and while I mostly have been happy, I still came back to nitro on the last few guitars.

edit to add - I don't know if you get the SM Trade Secrets - this might be helpful

https://youtu.be/u93PJtzVOXw

"I was thinking of cans but I’m also not opposed to spending up to 500 on a hvlp rig".

For a first foray into spray finishing guitars I would suggest buying a $99 pancake compressor and a $15 HF jamb gun. You won't get a perfect "off the gun" finish but you can get something that can be buffed out as well as most other sprayed finishes. The smaller high pressure guns don't waste a lot of finish to overspray if they are adjusted properly. There are some inexpensive HVLP gravity feed guns out there also if that is a "must". The average novice doesn't generally do any better with a more expensive setup and a small cheap compressor is useful for a lot of other things.

I already own a small 2 gal pancake compressor. I didn’t think it had the volume required for a spray gun. I figured HVLP was the way to go but maybe not for laquer?

I don't own a HVLP rig, I could be wrong but I think the switch to HVLP is driven by environmental concerns (and regulations), not finish quality. I paid $100 for my gun from Sears 40 years ago and it is still doing a good job.

I have a 5 gallon compressor that hardly comes on while spraying. Maybe a 2 gallon will do the job. I'm sure others will know. If I was you I'd look into getting a decent gun for the material you anticipate spraying, and a serviceable buffing wheel with the $500.

_________________
Joe Beaver
Maker of Sawdust

Sounds like a good idea

" I think the switch to HVLP is driven by environmental concerns (and regulations), not finish quality."

Environmental regulations were the push that many needed to go to HVLP, but originally it was and is sold as a way to waste less finish material. HVLP equipment generally gives a better "transfer rate" (when adjusted properly) than high pressure guns. Often it doesn't atomize as well. Larger droplets create less overspray which means more material ends up on the work but also requires more time for the finish to flow out.
Because we generally buff out our finishes a high quality "off the gun" finish is not really required, unlike a cabinetmaker or auto body shop that doesn't want to touch the finish after it is applied. An inexpensive small volume (8oz cup) jamb gun and a 2 gallon pancake compressor will work fine for spraying a small item like a guitar.
www.ebay.com/itm/HVLP-Mini-Spray-Paint- ... 0005.m1851
I use a high pressure siphon feed gun similar to this one:

www.ebay.com/itm/Husky-Siphon-Feed-Deta ... Swi7Zcj9~z

I think it has a reasonable transfer rate and atomizes the finish a little better than some of the HVLP guns, but again that is not a big deal for a buffed finish.
Even if you eventually buy a better gun, a cheap spray gun will still have its uses. I've never felt the need of a better spray gun but I do have several cheap ones with $5 HF regulators connected at the gun to adjust the air pressure.
For spraying a few guitars "al fresco" the small compressor and jamb gun might be handier than most setups. It's not hard to get carried away on expensive spray equipment and spray booths and explosion proof fans, and for a professional it might be necessary, but for the average amateur guitar maker I think it costs more than it comes to. YMMV

Ok, sounds like an inexpensive jam gun is the way to go for the next build, and for sure pick up the StewMac finishing book. Now as far as buffing goes, the large buffing wheel motor assemblies I’ve seen made for guitars are very expensive. Could someone get good results using an automotive type buffer? I have a 6 inch black and decker random orbit polisher, never really got great results with it on a vehicle but never tried it on anything else.

FWIW, I am now using a 3hp 8 gal compressor that I bought at a yard sale for fifty bucks. Added a good water filter and regulator and an inexpensive gravity feed gun. I shoot outdoors on a nice day, minor issues with dust and bugs. I have a pretty poor motorized buffer but I mostly use foam pads in a drill motor. I'm getting decent results

A 2 gal pancake compressor works fine. You just have to be patient and let the pressure catch up with your spraying. But that's not a big deal if you are not in a production environment.

No need for a big buffer either. I finished my first few guitars with the Stewmac polishing pads and compounds.
https://www.stewmac.com/Materials_and_S ... _Pads.html
https://www.stewmac.com/Materials_and_S ... ounds.html

You can get the pads for cheaper at an automotive supply store or on line. But they do a good job. It helps to have a plug in drill as you can drain a battery pretty quickly on a cordless. Just keep the speeds down so you don't cook your polishing compounds and wash the pads after use. Also best to have different pad for each grit of polishing compound. It's an easy way to get into good buffing results without spending a lot of cash. I still use them for touch up or repairs.

_________________
Tony Thatcher
Bozeman, Montana

Another tool I have used is a 5 inch random orbit palm sander with buffing bonnets I buy at the auto parts store. If it is variable speed so much the better. Since it is an electric motor I try not to use too much water and go at a lower speed. Buffing is the last step after hand sanding the finish flat with multiple grits of sandpaper

One way to cut down on bugs in the finish when spraying out doors is to cover the work with a large cardboard box after spraying.

I know that this thread is a week old, but figured what the heck, I'll throw in my nickels worth. the OP's original question was about book or video instruction. I found a good video series by Jeff Jewitt of Homestead finishing products. It is for spray finishing nitro Lacquer, and is very thorough, with a step by step approach. I purchased and downloaded it via Robbie O'briens website. It is worth looking into if you want a showroom quality lacquer finish. I wish it had been available years ago.

_________________
"It is easier to fool a man, than it is to convince him that he has been fooled"
Mark Twain

You can find finish info specific to guitars from nitro to UV cured poly on my blog. https://howardguitars.blogspot.com/2015/01/welcome.html

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

With spraying there's only so much you can learn from books and videos. Buy a decent gun (I use a SATA MiniJet IV with 1.2 mm nozzle for shellac, nitrocellulose, and water based lacquer) and a small compressor (a pancake compressor is sufficient for guitars) and start practicing. Understand the safety issues. Protect your lungs, don't poison your family, and don't blow yourself up.

Set up a spray area with good lighting and practice until you get the basics correct (gun travel speed and distance of gun from the work are both critical and you need to get a feel for how room temperature and finish viscosity and all the other factors come together). Don't worry too much about a spray booth if you are working with water based finishes; the great thing about spray finishing is that the finishes dry so quickly that overspray and dust are not big issues for finish quality. I spray and then open up my garage door for ~60 seconds to exhaust the overspray that is hanging about and keep the shop clean, then close the garage door.

If the finish off the gun isn't great, then sandpaper is your friend.

Bob Flexner, Michael Dresdner, and Jeff Jewitt's reference books and videos are all quite good. The Fine Woodworking "Spray Finishing" book is quite good. You'll find good videos on YouTube if you're willing to sort through hundreds of bad videos. These will help you understand what you're doing wrong when practicing.

If you decide to try rattle cans (I wouldn't), then make sure you buy rattle cans with good nozzles. The typical spray paint nozzle is awful. Automotive spray cans usually come with a much better nozzle. I've never bought them, but I think Mohawk sells specialty wood finishing cans that come with good nozzles.