Finishes

[Nick_Black]

hey, I'm starting to build a guitar (well, I just got the wood) purpleheart neck (neck thru body) with white ash body wings. I was thinking nitro finish, becouse thats what everybody seems to like, plus purple heart is pretty heard so it dosn't really need a thick finish, (but the ask is gonna soak it up like a thirsty horse.. from what I've heard) but anyway, my question.

what other options do I have for finishes
advantages/disagevantages (I jest read somewhere that nitro aperently scraches easy)

any info sites on using nitro (or some other finish maby?)

any sugestions will be greatly apreciated, thanks

 

[danw]

I know you're waiting to hear back from the luthiers on this one, but I'd be interested to hear more about this, too. I don't have spray equipment, so that takes a lot of the options out for me. So far I was looking at spray-can lacquer at Stewart MacDonald:

http://www.stewmac.com/shop/Finishi...vents/1/ColorTone_Aerosol_Guitar_Lacquer.html

and a water-based lacquer at LMI:

http://www.lmii.com/CartTwo/thirdpr...eader=KTM+Product+Line+%96+Water+based+Finish

I like the fact that the latter could actually be brushed on if need be, and it seems to be less toxic than nitro, but I haven't heard much about the quality of either one. My current project is made of cheaper materials, so I'm probably going to do something of the hardware-store variety on this one, but I'm hoping to make the next project a little better quality.

Oh, and man, that's going to be pretty. Purpleheart and ash. Looking forward to pics when you get that put together.

 

[cnix]

I have built 2 guitars from kits, and on both I used Tung Oil. This will not be colorful, but will be a nice finish. I did not have any type of compressor / with spray options at the time. I also thought that spray cans would look like crap, I could be wrong, but I did not want to mess up my "creation". Here is one of the guitars I built from a kit with 6 coats of Tung Oil.

http://s72.photobucket.com/albums/i183/cnix50/?action=view&current=CarvinKit2015.jpg

If you want radical, you had better invest in some equipment.

Good luck with your finish.

Charlie

 

[Nick_Black]

thanks alot for the great links!

danw: yeah I was also thinking spray can. that water bases stuff almost looks too shiny, and unfortunatly you have to purchase those "how to" video's from the first one... but great links none the less.
looking forward to seeing your prodj. too

cnix that is indeed a nice finish, and one I am now interested in. I have a heavy duty compressor, and I think I've got some decent spray atachments too.. (my brother painted his jeep with it.. so I'm not shure If I could still use it... depending if he cleaned it or not....

anyway's thanks for the sugestion and the pick!



one more question.. do you have to tape off the fret board? do it before you put on the fret board? or just spray over the fret board?

thanks

 

[Fusioninspace]

I do a fair amount of woodworking and finishing for furniture, cabinetry, etc. I was thinking of eventually finishing a raw wood guitar using an oil based polyurethane. I've had REALLY good results when I take my time and follow these simple procedures...

1. Sand the surfaces down to as smooth as you can get it. Start with 100, then 150, 220, maybe even to a 350 or something. You don't have to spend a long time with each. In fact you could probably do a solid guitar body in 5 to 10 minutes with each one. Just make sure you get every nook and cranny. You a sanding block for the flat parts and a loose piece for the detail work.

2. Clean the dust off. In fact spend the next hour cleaning out your shop/prep area of dust... And I mean clean. You don't want anything... and I mean ANYTHING floating around the room after this.

3. Stain if desired. I prefer oil-based wiping stains.

4. Here's the secret part... Mix thinner and poly (50:50) - Gloss is probably what I would use for a guitar. But that's just a personal choice. Mix slowly, your greatest enemy at this point will be bubbles in the poly. I think this is generally referred to as a sealer. The idea is that the thinned poly will soak into the wood and also provide a better surface for the full strength poly to stick to.

5. Apply the primer using QUALITY brush. On my projects I tend to buy a 5 to $10 brush for just that project. The sealer will not run like full strength poly - but still be carefull. The idea is to get an even coat on there and let it soak in.

6. When you're done, dip the brush in sealer and put it in a zip-lock bag. You actually don't have to "clean" the brush at any point during this process. Let it set until the next day.

7. Put your first coat of full strength poly. The key here is to NEVER have to wipe off extra poly off the brush. When you do it makes bubbles/foam in the can and on the brush. This is bad. The bubbles stay as bubbles and will cloud the final finish. When you prep the can, slowly mix the contents with a mixer (I use an old screw driver dedicated to mixing poly). Just dip the very tip of the brush into the poly. For the first couple of dips, apply the poly to a practice piece of wood to get the sealer off and to get you warmed up a bit before hitting your creation. You can do the dip in thinner or full strength poly/zip lock bag thing again here.

8. Let it set overnight or even longer - you want the poly to harden well for the final wet sanding.

9. Optional: Repeat step 7. Not sure this will add anything significant to the final product. I've tried both a single and double coat at this point and it doesn't seem to matter.

10. Wet sanding. Here's where the rubber meets the road. Use 330-600+ wet/dry sand paper... CAREFULLY. The idea is that you take down any surface imperfections/bumps. Get lots of water on the surface - don't worry, it's now sealed in poly! Soak the sandpaper and gently sand down the surface. Be extremely careful on edges. It takes no time at all for this part - you can probably do the entire body in less than a couple of minutes.

11. Cleaning - Clean up the surface with a moist cloth to get all the poly dust off. Dry before proceeding. In fact, I tend to just let it set overnight again.

12. Final poly - Similar to step 8. This can be your last step if you like what you get. Let it set a day or two before you start using it. The poly needs time to throughly harden.

13. Polishing compound/car wax. This is a great way to finish off your project and protect it. Use polishing compound to get those microscopic bumps off the poly and then a simple poly car wax to give it the final sheen.

I've been extremely pleased with the results of many wood working projects using this technique. You'll get a very deep looking luster and it will be extremely durable/scratch resistant.

The manufactures use their techniques because if gives good results and is fast. This method takes several days, but will yield similar results.

Good luck!

 

[donkeystyle]

hey, I'm starting to build a guitar (well, I just got the wood) purpleheart neck (neck thru body) with white ash body wings. I was thinking nitro finish, becouse thats what everybody seems to like, plus purple heart is pretty heard so it dosn't really need a thick finish, (but the ask is gonna soak it up like a thirsty horse.. from what I've heard) but anyway, my question.

what other options do I have for finishes
advantages/disagevantages (I jest read somewhere that nitro aperently scraches easy)

any info sites on using nitro (or some other finish maby?)

any sugestions will be greatly apreciated, thanks

the theory behind nitro is not only does it yellow and age in an interesting way, but it's wood based, so it (in theory) doesn't get harder or stay softer than the wood which allows the wood to resonate to it's full potential.

I personally don't know if there is a real difference between nitro and polyurethane, but I know light claims it's a pretty significant difference.

Nitro does dent a whole lot easier than poly, and it scratches a little easier.

Some polyurethane is really soft and some is really, extremely hard. As you would imagine it will affect the tone of the guitar.

I imagine the softer urethanes will look good longer than the harder ones (the hard ones will chip easier), but they will soften the attack of the guitar and deaden the sustain a bit. The hard stuff will probably make the attack brighter and also deaden the sustain. This isn't from experience, I'm just making a semi educated guess.

They are both really bad for you, so you need to be using a respirator and have decent ventilation.

Muttley and light will have more to say and either confirm or deny my guess'.

 

[muttley600]

As this one has been covered so many times in the past I was going to let Light field this one first this time, and then agree with him, but before we get to far into it here is my advice.

1. Do some searching here there is loads on the subject. You'll find that Light and myself STRONGLY advise against using nitro in a home setup unless you really know what you are doing. It can be very dangerous and for a small one off project there are much better options.

2. The Stew mac and LMI waterbased products can give excellent results if you use them correctly. They can be a bit more fiddly than nitro but they are worth the effort.

3 if you don't have spray facilities or are unsure about using rattle cans (they can be a bit unpredictable in the way they behave) then consider a brush or wipe on finish.

4. Tung oil is a good finish and natural. Even better is Tru oil. Despite the name it is not a true oil finish, it is closer to a violin type varnish and is entirely safe and very easy to get a good finish if you dedicate the time to it and are not after a mirror gloss. I offer it a finish option on many of my instruments I like it that much. It's a linceed oild based varnish with some modern polymers added.

5. I have never used oil based polyurethane on an instrument so I can't comment. I don't know what specific brush on finishes you guys in the States have available, but here Rustins Plastic Coating is very good. Many makers from small to medium have used it in the past as an alternative to hard polyesters. In theory just about any finish can be applied with a brush and then cut and buffed. Some are easier than others.

6. Before you even consider you finish you need to think about what sort of look you want. The timbers you have there provide some challenges if you want a flat clear finish. Ash is very open grain and will need some careful prep and filling if you want it flat and the grain filled. Purple heart can bleed colour into the finish and adjoining wood with some finishes. When you get to it pipe up and I'll give you some tips depending on what finish you opt for.

7. Whatever you do test on scrap first.

8. Whatever you do test on scrap first.

9. Whatever you do test on scrap first.

10. Go back and re-read points 7, 8, and 9, they are very important.

I'll step back and let Light steer you away from nitro as well now, but before I do, donkeystyle who told you this?

the theory behind nitro is not only does it yellow and age in an interesting way, but it's wood based, so it (in theory) doesn't get harder or stay softer than the wood which allows the wood to resonate to it's full potential.

It's rubbish. Not getting at you, it just it aint true.

As to the effect of a finish on an instrument. You are going to notice differences on acoustic instruments more than electrics and you can never really tell how much effect it has even then. As a rule you want as little as possible to give you a durable lasting protection to the wood. In the case of your first instrument go with whatever is easiest and keep it simple first time.

Having said that if any finish does kill the tone of your wood it would be polyester. I'm not to keen on the Urethane finishes I've seen either but on a first instrument thats not your biggest concern IMHO.

 

[Roguetitan]

if you want a natural finish use tung oil , Boiled Linseed oil or tru oil gunstock finishing kit.
if you want a high gloss painted finish use a polyurethane based spray paint it is flexible and dont crack like other finishes. if you spray it on flat the paint will lay down and produce a nice smoothe finish.
if you are wanting a translucent blue or red ect. finish Testors model car paints work well for these types of finishes. That is the least expensive method of applying a nice finish to your project.
it is either that or spend several hundred bucks for a compressor and a good paint gun and other miscelaneous painting supplies.

Nitrocellulose finishes are a pain in the ass!

thats my .02

 

[jimistone]

the theory behind nitro is not only does it yellow and age in an interesting way, but it's wood based, so it (in theory) doesn't get harder or stay softer than the wood which allows the wood to resonate to it's full potential.

What does "wood based" mean?

Nitro is good IMO because it's easy to level, cut, and buff...it's easy to spot repair the finish when you get a bad ding...it's usually sprayed on thin and supposedly allows the guitar to resonate better (I have never seen convincing proof of this)...and a nitro paint job wears easily which gives a guitar the relic look with time (very desirable these days).

A poly paint job still looks brand new after 30 years and if you ding it it's nearly impossible to spot repair. Also, if you ever want to take a guitar back down to the wood for a different paint job at a later time....Nitro comes off very easily.
Taking a poly finish off is pure hell. Aircraft stripper dosen't even lift that stuff worth a crap. You can let the stripper pool up on the finish for 2 freakin' hours and there MIGHT be one tiny spot half the size of your finger tip starting to life a bit.
I'm in the middle of taking a poly clear finish off a Korina Epiphone V...IT SUCKS!

As far as yellowing goes...If you don't want yellowing just use Deft laquar for the clear (walmart carries it). Deft won't yellow, but if you want the yellowing you can use the clear nitro laquar that yellows.

 

[Zaphod B]

What does "wood based" mean?

Jimi! Good to hear from you. How ya been?

 

[jimistone]

Jimi! Good to hear from you. How ya been?

I have been doing OK.
Thanks for asking.
I have really been busy lately and haven't had much time to post...but I figured it would be fun to post my opinion about nitro guitar finishes and get flamed.

 

[Nick_Black]

WOW there's ALOT of good/interesting/useful info on this page, HANKS ALOT GUY'S (and/or girls?)
+ Rep for everyone


Edit: I actualy think I might go with the tru oil, it looks (after googleing a bit) like the finish I'm looking for.

just one more quetion, do you spray the frets too?
or do you tape them off?

 

[jimistone]

WOW there's ALOT of good/interesting/useful info on this page, HANKS ALOT GUY'S (and/or girls?)
+ Rep for everyone

just one more quetion, do you spray the frets too?
or do you tape them off?

You can coat them with vasoline when you're ready to spray...the paint sits on the vasoline and dosen't stick to the frets.

You can wipe the frets off when the paint stain/paint/clear dries. Just don't get any vasoline on the wood.
Or you can tape off the frets too.
Or you could paint the frets and clean them up later.

There are alot of different ways of doing things.,

 

[muttley600]

WOW there's ALOT of good/interesting/useful info on this page, HANKS ALOT GUY'S (and/or girls?)
+ Rep for everyone


Edit: I actualy think I might go with the tru oil, it looks (after googleing a bit) like the finish I'm looking for.

just one more quetion, do you spray the frets too?
or do you tape them off?

Mask them off if you want a non lacquered f/b. If you want a lacquered fingerboard tru oil is probably not the best choice. Doing a decent lacquered fingerboard is a pain in the butt whichever way.

If you going with tru oil you need to think about grain filling as it doesn't have great grain filling properties (actually one of it's plus points). You can avoid colour bleed on the purple heart by sealing with shellac/french polish which will give you a good base for the tru oil in any case. Once it is sealed sand it back and rub on a very thin coat being carefull not to drag any remaining colour off the darker woods into the ash. If you don't mind the finish dropping into the grain then you don't need to worry about grain filling. To get a good tru oil finish sand it down to at east 1000 grit going through the abrasive grades from 240 on. The more time you spend on prep the better the results will be.

 

[Nick_Black]

jimistone: thanks I didn't think about vasoline.

muttley600:, what kind of finishes do you use on your fretboard? (I know I don't realy need a finish for purple heart, but it'll be nice to know)

and what are your opinions on using shellac as a finish? it doesn't seam as natural looking as the tru oil, but it doesn't seam as fake shiny as some other finishes...

Edit: reading a bit more shellac dosn't seam that great...(as a finish, I think I will seal my guitar with it like you sugested (practicing on scraps first of course) )

 

[muttley600]

jimistone: thanks I didn't think about vasoline.

muttley600:, what kind of finishes do you use on your fretboard? (I know I don't realy need a finish for purple heart, but it'll be nice to know)

and what are your opinions on using shellac as a finish? it doesn't seam as natural looking as the tru oil, but it doesn't seam as fake shiny as some other finishes...

I don't do lacquered f/b's but if I did I'd go with the hardest finish I could find. Wear resistance is what you want in that case. I'd even consider finishing the neck separate from the body. With a neck through thats not easy. On the few lacquered f/b,s I've done they have been repairs on fender stuff so have used whatever was on them to start with, normally nitro. What fingerboard timber are you thinking of using, because unless it's light coloured such as maple I wouldn't finish it. Just feed it with a non drying oil of you choice once you are done.

Shellac is French Polish so it's probably one of the most natural and finest looking finishes out there. It's so natural everything involved in a basic french polish regime is edible, alcohol and insect poo basically. Tru oil is a polymerised linseed oil as I said so it is very close to a good violin varnish but better for guitars in many respects. All finishes can look great when done correctly it's really a matter of getting the look right and the durability you feel you need.

 

[Zaphod B]

but I figured it would be fun to post my opinion about nitro guitar finishes and get flamed.

It never fails!

 

[Zaphod B]

If you going with tru oil you need to think about grain filling as it doesn't have great grain filling properties (actually one of it's plus points). You can avoid colour bleed on the purple heart by sealing with shellac/french polish which will give you a good base for the tru oil in any case. Once it is sealed sand it back and rub on a very thin coat being carefull not to drag any remaining colour off the darker woods into the ash. If you don't mind the finish dropping into the grain then you don't need to worry about grain filling. To get a good tru oil finish sand it down to at east 1000 grit going through the abrasive grades from 240 on. The more time you spend on prep the better the results will be.

So then what's the protocol, Muttley - the order of business for using Tru-Oil?
Do you seal > pore fill > sand to 1000 > stain > Tru-Oil? Or some other order?

 

[muttley600]

So then what's the protocol, Muttley - the order of business for using Tru-Oil?
Do you seal > pore fill > sand to 1000 > stain > Tru-Oil? Or some other order?

The regime depends a bit on what timber you working with and what finish your after, satin, matt, gloss etc.

My usual process would be something like this but I might change it if I had open grain timber, a sunburst to do, translucent, Sometimes I'll do something to "pop" the grain on highly figured stuff, essentially-

Finish sand to 1000 grit. wetting the final coat to raise the grain a little.
Knock the raised grain off with 1000 grit.

Next fill according to timber, might be loads might be none at all.
re sand to 1000 grit. I sometimes go as high as 4000 as it helps the finish level and any little scratches etc are a no no under a thin finish.

I'll then stain with a water based aniline dye if required or do the burst etc.
then seal the whole thing with shellac. A few wash coats carefully applied locks everything in the prep down before building the finish.

Next comes LOTS of VERY thin hand rubbed coats of tru oil. I can get two maybe three a day on depending on a few things. By thin I mean thin a tablespoon full will cover the whole instrument.

I'll put at least a dozen on then let it harden for day and very lightly scuff out any nibs and load up some more, maybe another five or six coats. By now I should have a very thin very shiny finish. I'll let it dry for a week and use OOOO wire wool to knock the gloss off or then use a fine burnishing cream if I want a mirror gloss. The latter is hard to do with tru oil but with care it is possible.

As I say the process will vary depending on what I'm working with and a bit of judgment from me. It is an easy finish to do and can look fantastic. The biggest problem is keeping dust off it as it dries so cleanliness is paramount, and the other thing is not to rush it. Another great thing about tru oil is it is easy to touch in or repair.

I do a handful of these type finishes every year and always enjoy them. It's as satisfying to do as french polish without some of the possible pitfalls for the first timer.

 

[Zaphod B]

The regime depends a bit on what timber you working with and what finish your after, satin, matt, gloss etc.

This actually looks like a regimen that can be learned by a non-professional such as myself. Can the shellac wash coats be applied by wiping rather than spraying?