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  #1  
Old 08-21-2014, 12:23 AM
70man 70man is offline
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Default What the best way to remove Nitrocellulose laquer

Hi ,I've been looking to find a way to remove Nitro from a guitar,so it can be refurbished.Could someone point me in the right direction,and if there is a product ,what is it's chemical composition not a brand name,as I know I wont be able to get a branded product here,because I don't reside in the States.
Thanks
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  #2  
Old 08-21-2014, 07:27 AM
charles Tauber charles Tauber is offline
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You can effectively use any one of or combination of a chemical paint stripper, coarse sandpaper and a cabinet scraper.

Your local hardware or paint store will sell paint strippers. If you instead use sandpaper, start with 80 grit to do much of the work before switching to 120, then 180 and 220.

If you use a paint stripper - and neutralize after stripping - afterwards, sand starting with 120.

Regardless of your chosen method, ensure that you fully remove all of the scratches of the previous grit of sandpaper before going on to the next.

Chances are that refinishing your guitar is a lot more work than you think it will be.

Last edited by charles Tauber; 08-21-2014 at 07:32 AM.
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  #3  
Old 08-21-2014, 10:04 AM
John Arnold John Arnold is offline
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Most any paint stripper will do the job, but you must keep it off any plastic bindings or rosette. It will melt them just as efficiently as the lacquer.
You can also remove lacquer with plain lacquer thinner or acetone. It takes more work (rubbing and constant reapplying), but there is less danger of damaging plastic parts.
Be aware that there is risk involved in using many of these chemicals. Lacquer thinner and acetone are highly flammable. Many paint strippers contain methylene chloride. While it is not flammable, breathing the fumes is known to cause an irregular heartbeat, and it is a suspected carcinogen (as are most chlorinated hydrocarbons).
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Old 08-21-2014, 10:24 AM
Frank Ford Frank Ford is offline
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To echo John, here are some thoughts.

I'm interested in your choice of words - "refurbish" isn't a word I use, because its meaning so vague. So, for more specific recommendations, I suggest you give complete details about the project - make, age, materials, and, most important of all - your goal. Photos help here, too, of course.

As with just about any technique, there's no best way. And, of all the processes in lutherie, none is more challenging, difficult, tricky, unpredictable, frustrating or otherwise indescribable as getting a perfect, thin, glass-like polished lacquer finish.

That said, it's not impossible to do a decent job, provided you don't work at the Collings factory and have to pass their final inspection (insert your own "smiley" here).

Any regular paint remover will strip nitrocellulose lacquer nicely, although the different products vary a lot in viscosity, so I'd choose the least runny one I could get. Solvents such as acetone, methyl ethyl ketone, butyl acetate or lacquer thinner will dissolve lacquer, but they can be difficult to work with because of their volatility and low viscosity.

YOU MUST KEEP PAINT REMOVER AND ALL OTHER LACQUER SOLVENTS COMPLETELY OFF ANY PLASTIC ON ANY INSTRUMENT.

If the lacquer is quite new, some judiciously applied heat may loosen it easily. My old pal, Michael Hornick once showed me the entire, unbroken film of lacquer that he'd taken off a freshly finished guitar neck using a heat gun held at a distance. The finish was still all in one piece! From heel to the end of peg head with no blistering, no cracking - it looked like the nitrocellulose equivalent of a recently shed snake skin.

Well, that's about it for now from the Department of Early Warnings. . .
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  #5  
Old 08-22-2014, 10:42 AM
arie arie is offline
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fire is always a popular choice:



that pesky lacquer will be gone in no time. nothing beats results...
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  #6  
Old 08-24-2014, 04:12 AM
70man 70man is offline
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Quote:
Originally Posted by arie View Post
fire is always a popular choice:



that pesky lacquer will be gone in no time. nothing beats results...
Hahahahahaha ah yeah No.That's the worst suggestion yet
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  #7  
Old 08-30-2014, 03:24 PM
sfden1 sfden1 is offline
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Quote:
Originally Posted by Frank Ford View Post
I'm interested in your choice of words - "refurbish" isn't a word I use, because its meaning so vague. So, for more specific recommendations, I suggest you give complete details about the project - make, age, materials, and, most important of all - your goal. Photos help here, too, of course.
The above from Frank Ford is key, and I'd be interested in your responses. For instance, if the guitar is an old Martin or Gibson, removing the original finish could significantly affect the value of the guitar, no matter how beat up the current finish is, something to be aware of. So, make, model and age (and photos) would be good to know.

Also, refinishing the guitar to something that looks nice is not an easy task. Do you intend to do that yourself, or have it done by someone with more experience? If the latter, why not have that person remove the existing finish?
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Old 08-30-2014, 04:24 PM
Staredge Staredge is offline
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I was going to suggest



but fire seems to be a little easier to obtain.
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  #9  
Old 08-30-2014, 08:18 PM
Howard Klepper Howard Klepper is offline
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Quote:
Originally Posted by 70man View Post
Hi ,I've been looking to find a way to remove Nitro from a guitar,so it can be refurbished.Could someone point me in the right direction,and if there is a product ,what is it's chemical composition not a brand name,as I know I wont be able to get a branded product here,because I don't reside in the States.
Thanks
It's pretty safe to say that if you need to ask, you shouldn't do it.
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  #10  
Old 08-31-2014, 05:47 AM
Quickstep192 Quickstep192 is offline
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I'm far from an expert, but I've often read that luthiers and furniture makers like nitro because even after years, new coats will "burn in" to old coats, making nitro infinitely repairable. This makes me wonder if there are alternatives to removing the finish.
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  #11  
Old 07-14-2017, 02:01 PM
EastTexasRed EastTexasRed is offline
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Default If you need to ask, you should ask

Quote:
Originally Posted by Howard Klepper View Post
It's pretty safe to say that if you need to ask, you shouldn't do it.
I can't see why an amateur shouldn't have a stab at refinishing a guitar, and sometimes the knowledge held by luthiers isn't available except by asking. Of course, it's probably not wise to try something like this on a high end guitar but it's not obvious what sort of guitar is under discussion here. I'm an amateur and I've got two 12 strings (both 1975, one a Fender F-55-12 and the other an Epiphone PR-650-12) and a really cheap Encore 6 string. They're all great to work on because it doesn't matter if I make a few mistakes here and there. I've been learning how to make my own nuts how to level frets etc. Most of my advice comes from watching Dan Erlwhine videos and sometimes you have to ask questions as well.

I thought this question was interesting because I really dislike hard, high-gloss finishes. I think it was Dan Erlwhine again who recommended Tru Oil for a good, more natural looking finish. So I was curious as well how to remove nitrocellulose.
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  #12  
Old 07-14-2017, 02:20 PM
joeguam joeguam is offline
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Sorry, I didn't read the entire thread but I've re-finished a couple of instruments that had nitro on it originally, one had plastic bindings. I used lacquer thinner (from Home Depot) in a continuous cycle of:

1. Dab thinner in a small area with a brush
2. Wait a few seconds for it to penetrate and turn gummy
3. Scrape with a credit card

This gets most of the layers removed, then I sand properly using numerous grits as I would normally finish an instrument. I've done this a couple of times in instances where the finish was much too thick for my liking. I've refinished with 10 light coats of TruOil and the sound significantly improved each time. It was like stripping the lacquer freed the wood from a stray jacket and let it vibrate freely.
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  #13  
Old 07-14-2017, 02:27 PM
Sperry Sperry is offline
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After eight fairly good coats on the small wooden top of a bouzouki, I totally flubbed the ninth (I was spraying 3x3). After waiting a week for the lacquer to harden, I used a palm sander, running up to 220. Then hand sanding with the grain. No worries.

Careful not to gouge the wood. Enjoy the project!

If you're spraying again, keep your nozzle clean
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  #14  
Old 07-14-2017, 09:39 PM
mirwa mirwa is offline
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Personally, I dislike any chemical stripper being applied to the surface, it can reak havoc with new finishes.

A heatgun and a scraper work extremely well for removing the bulk, follow up with some 220 rig sandpaper.

Steve
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  #15  
Old 07-15-2017, 08:41 AM
Wozer Wozer is offline
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Quote:
Originally Posted by mirwa View Post
Personally, I dislike any chemical stripper being applied to the surface, it can reak havoc with new finishes.

A heatgun and a scraper work extremely well for removing the bulk, follow up with some 220 rig sandpaper.

Steve
what he said...

the first project I ever sprayed was a bar for a restaurant...I used PPG DCA-468 and really layered it on, wet sanded it and polished it to a show car shine...being that it was my first project I was a bit ignorant of the fact that it would need a lot longer time to fully cure and be ready to actually be put in use...well the night before delivery I noticed the finish was still rather soft and had read that Corvettes that used the same lacquer were run through a baking booth to both reflow the clear and also speed up hardening, so I put a couple of 500W halogens pointed at it with the plan to move them every 20 minutes or so...well, having stayed up 36 hrs straight to pull this polishing off (was being cautious and using a ROS for the polishing as opposed to a buffer that has the danger of toasting the finish) I ate a bit then proceeded to pass out on my recliner for 2 hrs...long story short I awoke and found the finish bubbled up and destroyed...the next day I started removing the finish via various methods and the going was VERY slow, then my brain said "hey, why not do what destroyed the finish"...using the same 500W halogen lights I heated it up and was able to use a chisel to get underneath the finish and literally pull up sheets of it along with the grain filler that was between the sander sealer and top coat...

of course be very careful of how much heat is used as on an acoustic guitar we're talking about woods less than 1/8" thick as opposed to a 3/4" bar top

p.s. DON'T use a chisel on your guitar, use a scraper as mirwa recommends
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