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Sanded through again. Again. I'm dying here. I've blown right through every deadline I've given myself for this guitar. Help.

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sweat the small stuff.

oh yeah, its the worst part by a long shot! it'll break your lungs and central nervous system too, if you don't have good ventilation and masks!
maybe reset your ideals and stop trying to achieve a modern, deep-n-glassy factory finish...? as long as the sweat and beer stays out of the wood, the finish is perfect.

are you using an eraser or some other sanding block? I know it helped me a lot but I still had sand-throughs. Giving yourself lots of finish to work with helps, so does giving it plenty of time to dry and keeping your sandpaper clean of the little corns that build up on them is imperative. The little corns on your paper end up scratching the finish deeper than the grit of the sandpaper you're using which for me meant going back down several times in grit and I didn't have enough finish left (ouch)

Maybe if you describe how much finish you're putting down, what kind of guitar you're finishing people will prolly just start pouring in help.

I mostly just wanted someone to talk me down. My standards are really high and it's just not going to be easy with the method I'm using. This is only guitar number two, but I did a pretty nice job. My first guitar was nearly flawless from a wood working perspective. It plays and sounds really great. The finish is a joke though. I've already taken this one all the way back down to wood once, so I really just want to get it finished and move on. It will be played by a gigging local musician and will likely see some abuse. Meaning, even if its perfect when it leaves the shop, it won't be for long. It's an OM finished with KTM-SV over Z-proxy. I brushed the finish on and as smooth as it went on, it just took too much leveling and I sanded through in one spot along the back strip in the lower bout area. It makes me sick to my stomach. I will NEVER brush a finish on again. Time for a spray rig.

Ok, so enough complaining. Do I just spot fill and try to feather it in the best I can? It's a spot about 1/2" by 1/4". Smaller, actually. The back and sides are Honduran mahogany and the back strip is quilted sapele. It sits right on the back strip. Can't really see it, but I can feel it. Now what?

Thanks for listening.

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sweat the small stuff.

I brush on shellac and I've never sanded through. Get some of that veneered covered board and practice. You can make as many mistakes as you like. I found brushing on Shellac pretty difficult at first, actually it seemed near impossible.
If KTM-SV can be brushed on (I assume that it can) then it can only be a matter of technique and a bit of practice.

I know this sounds painful but start with a finer grit and good lighting and as soon as you can not see orange peel in that area STOP.
It takes longer and hurts your shoulder but it has saved me many an overspray

I'm not so sure you can blame it on brushing. You can get uneven coating thickness with spraying as well. Sounds possible that your backstrip may be of a harder wood than your back, and that it may be a slight high spot from your final sanding as the soft wood sands faster than the hard. Just as can sometimes happen on the bindings. For a spot that small, I'd just kick the bench and try to do better next time.

Keep at it, finishing is not easy. I am on #17 and still have some issues with every one, but they are getting easier to deal with. Finishing is a huge part of the learning curve but once mastered a great source of pride. I just airbrushed some lacquer on a blemish on the rosette on #17, it will be under the clear pick guard and would never have shown but I would know it was there so I fixed it.

Quit making deadlines, it takes all the fun out of building guitars.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Haha. Normally I would agree, but I started this guitar a touch over three years ago. It is BEGGING for strings.

Thanks for all of the advice. I know I can't solely blame the application method, but I'm pretty sure I could lay down a smoother coat with a spray gun. Maybe I'm fooling myself.

I think I was trying to sand too large of any area. Should have concentrated on smaller areas and using a finer grit would have helped.

Any advice for repair?

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sweat the small stuff.

+1 Fred.

That is not totally true but spraying does make life easier. Don't give up,.the process gets easier with practice. There are a lot of builders who never do any finishing, but if the guys like Joe White stop doing their work they will be in a bad way trying to make their guitars look as good.

My big eye opener was doing my black top guitar, everything shows like it is magnified on black.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Word.

I'm about where Fred is at building wise. Finishing is definitely the hardest part of producing any kind of world class product. I used to manufacture another product and finishing plagued me there initially also.

I'd also advocate learning to spray your finishes. Sure....you can screw up that too...but spraying offers quite a bit more latitude than brushing. Get an HVLP gun and follow the specific instructions of the manufacturer for thinning, orifice size, pressure...follow it all to the letter. Once having become practiced at that you can make adjustments. Don't be afraid to put in some time practicing on test panels....sealing, pore filling, and top coating...start to finish. I learned to use a number of different finishes by mastering the finishing of test panels long before I approached a guitar.

Spraying any topcoat onto a properly prepared, FLAT surface was the thing I needed to get into my head before things started gelling. Spraying the topcoat material down evenly and smoothly is a different issue but the surface prep was the controlling issue for me.

Good luck. I know it's frustrating to face all the work that goes into finishing while having doubts about the outcome. We've ALL been there. I'm not sure how much talent is required to master finishing. I DO know it requires patience and perseverance...but it is QUITE rewarding when you have a handle on it. As you go through the final grits and compounds the guitar blossoms into existence.

Hang in there! You'll get it.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

TBH a spray set up seems very excessive. If it's taken 3 years to get this far it doesn't sound like you are making enough instruments to really justify a spray set up. Using a brush isn't that difficult and it has the advantage of being very simple, no extraction booth required.

+1 to what Todd said, surface prep is the key. And for brushing, level sanding between coats is also key. Two or three coats, dry for a couple of days, DRY sand with 400 or 600 till the shiny spots are gone. You may sand through in a couple of spots, but that tells you where your problem areas are. Then do it again. After three or four iterations, you'll have enough thickness and can let it cure for 3 or 4 weeks. Then final WET sanding will be much easier.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

Quit making deadlines, it takes all the fun out of building guitars.

Fred

It's already been said. 3 Finish Rules
Prep, prep, and Prep
You can't level sand a finish over uneven wood.
My last finish (no 5) was half decent because I tried to bear this in mind from early on during the build, after earlier finish problems.
It was much less painful - still working on it, but I think I can see light at the end of the tunnel.
And I wouldn't discourage you from buying a spray system - it's nice to have a high end system, but an occasional builder don't have to break the bank for a workable HVLP.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I've reached the point where the vast majority of the difficult block sanding occurs before I put anything on the guitar. Once I start spraying I feel like the worst is behind me.

I've brushed and sprayed. I think it's a lot easier to level out a sprayed finish - no brush marks and should be more even. Started out spraying from a $30 Walmart detail gun with this hi-tech spray booth.


Since then I acquired a used explosion proof fan and built a small spray booth in the corner of the shop. I also invested in a decent Walcom EGO HVLP gun and filters for the air. My latest addition will be a desiccant filter that I ordered last week. My total investment is around $1200. Not up to pro standards but it works well for me. It's not so much about being cost effective but about trying to get the quality of work I want.

Edit: I was doing some spraying this morning so I snapped a photo of my "booth". It's not enclosed but I'm spraying waterbased lacquer so I'm not worried about it. The fan does a good job of catching the spray.

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Steve Smith
"Music is what feelings sound like"

Taht's waht I'm talking about.
Although I'm not to sure if you need the frog...

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

IMO, if you're sanding through, you're not putting enough finish on prior to sanding, or you are sanding too aggressively. In the initial coats, don't try to get a mirror smooth finish... just level it.

Like others have said prep and decent spray equipment.A good buffing system is equally important.This can be the final step to begin selling guitars.Even though I only had 5 commissions last year. I never could have got them without a quality finish.

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James W Bolan
Nashville Tennessee

Get an airbrush for this kind of repair. Lay down a layer or two. Then gently sand off any gloss (320-400) and do again. Eventually it will level off and look great. Do not tape off the area.

Todd is right though. Sand throughs can be attributed to "high spots" in the wood, places that were not blocked properly.

Mike

I now start leveling with 600 instead of 400 and I have eliminated sand throughs (for me).
Michael

For small volumes, brushing is fine. You can get as good a final outcome as any spray finish, though it might take more time. If you use foam brushes, though not ideal, there's virtually no cleanup. No booth needed either. Take the time to learn the skill.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

One of our dogs would be traumatized if we lost the frog - it's his favorite place to pee

No argument on brushing. Definitely can get a quality finish that way. Spraying is just easier if you have the equipment IMO.

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Steve Smith
"Music is what feelings sound like"

For a local high spot, is there a safe way to buff it?

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David Malicky