Getting started with finish repairs?

Wallaby

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Greetings and salutations Earthlings :D

I've searched TDPRI bit, read a bunch of posts, watched videos, have very minor experience using a compressor and spray gun 25 years ago. ( A neighbor kid's BB-gun aimed at my driveway visqueen spray booth one summer afternoon ended that experience negatively :/ )

I'm interested in finding learning resources. Videos, classes, books, etc. to get started with finishing and finish repairs.

As I progress and increase the range of repairs and things I do with guitars, I can see that until I learn to at least touch-up or overspray repairs there is a border I can't cross, where actual finishing is needed.

E.G. - a bound fingerboard with fret-sprout-related binding cracks could possibly have its binding replaced. But not by me. I'm not capable of repairing the finish once the new binding is installed.

Videos I watch make it look easy and slick, a few minutes with an airbrush and voila! And I know it isn't easy :)

My humble request, if you have any advice, sage words, links to good training resources, secret handshakes - I'd love to know about them!
 

Peegoo

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Repairman Dan Erlewine's book series on Guitar Repair is a good start.

Using an airbrush, a typical spray gun, or an HVLP setup takes practice, and the learning curve never really levels off because there are so many...contingencies...encountered when doing spot repairs, partial refins, and complete finish jobs.
 

Freeman Keller

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Wallaby, some general observations and comments

- choose one system and get to know it. I personally find that nitrocellulose lacquer is relatively easy, gives good results, is very versatile, and can do both new and repairs. There are obviously other options and I've tried a couple, they will have their own learning curve. I may come back to this later....

- refinishing and finish repairs are much much harder that starting from scratch. Its like building a guitar vs fixing it. I would much rather bind a neck than replace binding on a neck, yadda yadda. When you start from bare wood you are in control of each step and you are usually spraying a large area. With repairs you need to worry about compatibility and mixing solvents and matching colors and a whole bunch of things. I think I do fairly nice new finishes, I futz and worry every time I do a repair

- learn your gun and compressor, keep the gun clean, practice on scrap. I do take the time to empty my gun between coats even if I know I'll be shooting again in an hour. I take it apart and clean it. It never gives me any problems when I do.

- back to my first point, lacquer is probably the easiest to repair outside of FP. You can drop fill with lacquer and new finish will melt in to previous coats. Other than shellac I don't know anything else that does this. It is still hard to match old lacquer with new and in many cases refinishing or repairs may not be the best for an old guitar.

- if you choose lacquer I also recommend staying with one manufacturer's complete line. I have used a couple of different brands and my understanding is that there can be some differences, particularly with solvents. So I try to use the same sealer, clear or satin finish, and thinners from the same manufacturer. I buy generic lacquer thinner for clean up but I use the brand's for thinning my finish.

- still thinking about lacquer, one of the really cool things about it is that you can almost literally do anything you want with it. Thick for an electric, thin for an acoustic. Gloss, semi gloss or satin. You can tint it for transparent color or put pigment in it for opaque. Its fairly easy to do sunbursts and fades. Spray gloss over your color coats to give depth. If you get runs or dust or bugs in your finish let it dry and sand them out.

- solvent (nitrocellulose) lacquer is also toxic and explosive. Wear a respirator, be careful of sparks and such. I shoot outside on a day with good temp and humidity rather than make a spray booth.

I highly recommend Dan Erlewine's book on guitar finishing. Yes Dan was a StewMac employee and his book is oriented around their stuff - actually that is a bonus. There is also a good how to finish guitar at Reranch and Brian Howard's page on finishing problems is well worth book marking


I also have StewMac's finishing schedule book marked and refer to it often. If you follow their steps you will get a good finish.


- last comments are about finish repairs. Some I don't even attempt - most modern catalyzed finishes for example. I might try drop filling with GluBoost but often I don't try. Vintage guitars which might be possible I often don't try either - a refin can cut the value in half. I try to touch up repaired cracks - I tell owners that the repair will be structurally sound but it may not be cosmetically perfect.

- I use a small gravity feed HPLV gun for all of my finishes but for small repairs I sometimes use an airbrush. With nitro you can mist on a coat getting it fairly wet at the repair and when dry you can sand and buff the edges.

- I've also learned to be realistic with my expectations. I would love to be able to lay down as new finish as nice as a $400 MIC import. I would love to be able to touch up repairs as well as Erlewine or Frank Ford or Brian Howard - I can't do it.

ps - you asked about resources. In addition to the ones I mentioned above StewMac's site is full of them. As is Frank Ford's frets.com . Spend some time at the GluBoost site, there stuff is about the only way I know how to fix poly. And then practic....
 
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Freeman Keller

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E.G. - a bound fingerboard with fret-sprout-related binding cracks could possibly have its binding replaced. But not by me. I'm not capable of repairing the finish once the new binding is installed.

This may not be a valid example. I don't think I have ever seen a bound neck where the fret ends actually damaged the binding. I've refretted a lot of bound necks, I've replaced binding but it mostly just came unglued. Some very old guitars with celluloid binds it just crumbles and falls apart, but all of these are pretty major repairs.

I have replaced binding by routing the old stuff off and redoing it, then trying to match the ambered finish over it - that is a bunch of work and has never come out "perfect".
 

Wallaby

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My brain... is exploding - thank you!

Bookmarks are bookmarked and reviewed once already. Planning a little book shopping, reading.

I'm actually pretty handy with shellac, from flake, and french polishing and brushing, retarding, reducing, etc., but for furniture. Hopefully the concepts carry through.

I'm grateful for generous spirits :D
 

trev333

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E.G. - a bound fingerboard with fret-sprout-related binding cracks could possibly have its binding replaced. But not by me. I'm not capable of repairing the finish once the new binding is installed.
Yes, you are..;)

When someone brings me a dump find to repair. I see it as an opportunity to learn how to do it ... with the knowledge it isn't worth much as it is and I can only make it better/playable.

I haven't even got a compressor/spray set up...

SX before.jpg
SX fix1.jpg
SX fix after3.jpg
SX fix2.jpg
SX binding1.jpg
SX finished.jpg
 

trev333

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The only damage was on the bass side.... I didn't touch the treble side...

I matched the white binding to the old binding with shellac... and used black spray can acrylic to touch up the bare wood.... and made a new nut...then gave it a polish..:)

took a while to get it close...
 

trev333

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then there was El Kabong san. :)

a Yamaha nylon string that sounded wonderful afterwards... that went to my guitar class kids at the school.

It is a good feeling repairing these broken guitars and giving them a new life. There's plenty out there that need fixin'...;)

yamaha1.jpg
yamaha2.jpg
yamaha12.jpg
yamaha13.jpg
 

Wallaby

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FYI - I'm reading and attempting to understand the StewMac finishing book ( there was a special ). I got nothing at this point, just seeing how all the parts fit together.
 

Wallaby

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I meant to post this a while ago and just found it in my notes file and realized I hadn't. In the video at 3:30 the neck binding cracks I referred to are shown



I don't think I have ever seen a bound neck where the fret ends actually damaged the binding.
 

Freeman Keller

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I meant to post this a while ago and just found it in my notes file and realized I hadn't. In the video at 3:30 the neck binding cracks I referred to are shown



Oh I didn't say it couldn't happen, I just don't think I've seen it. There is a bit of a difference when fretting over binding compared to no binding, and different again with nibs. With no bind you just run the fret to the edge of the board, clip it off and file it back smooth. If the board shrinks back the fret sticks out. With binding most people put the binding on first, then cut the frets to fit in between. Commercial places frequently automate this so the fret is pretty accurate, I try to leave a very slight gap between the end and the binding. So if the board shrinks there is a bit of gap. Nibs have the binding channel cut but not bound. The frets go in and are filed level with the edge of the channel, then the binding is installed. The top edge of the binding is proud of the board and is sanded or scraped down level. That puts the ends of the frets tight against the binding and could certainly push it out or crack it.

As they discuss in the vid, fretting over binding is a little bit tougher than straight fretting, nibs are a whole lot harder. I've been in discussions at lutherie forums about keeping nibs or nixing them, and this can be a hard choice. Many of the guitars with nibs were the wonder old jazz archtops and hollow bodies and they are valuable instruments. Most people feel that a refret doesn't hurt the vintage value by sanding the nibs off might. On the other hand, if there is any gap between the fret and nib you can push a 10 gauge high E right into the slot.

Tough choices, I have dodged them by not refretting the nibbed guitars that were brought to me. I'm quite happy fretting over binding, most of my guitars are bound, but someone else can have the big bucks.
 




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