what is the best Varnish to use

[newbe]

I am at a stage now to sand and varnish the guitar
What is the best varnish to use

[thetragichero]

so i'm guessing you're going for a natural or dyed look instead of a solid color? what equipment do you have? if you have a compressor and a paint sprayer attachment (even the cheap harbor freight guns aren't horrible for guitar work) varathane waterbased polyurethane (use gloss and if you wish a satin finish you can not do a full finish sand and polish regiment) is very forgiving to work with and depending on temperature and humidity you can lay fairly thick coats and reapply 30-60 minutes later. there is an epic thread on the talkbass forum with folks who use the varathane. you want even coverage but you've gotta stop before it gets cloudy/blue or it'll run (i have a heavy hand so i find instead of hanging vertically to dry doing a side at a time (alternating) and drying horizontally works better for me)

[newey]

Aug 12, 2021 21:24:55 GMT -5 thetragichero said:

if you have a compressor and a paint sprayer attachment

I'm with TragicHero on the hanging vertically thing, I always get runs that way. As for sprayers, those Preval sprayers (that use the disposable propellant canisters) work decently for guitars. As with any finishing job, surface prep is everything.

Also, plan to let the finish sit for several days before you start sanding, etc. You can sand it sooner, but you probably shouldn't

Unfortunately, our resident refinishing guru, cynical1, isn't around much anymore to help with this sort of inquiry. But if you go back through his posts in response to refinishing questions in this sub-board, you'll probably get a good feel for what he'd recommend.

[reTrEaD]

Aug 12, 2021 21:31:52 GMT -5 newey said:

I'm with TragicHero on the hanging vertically thing, I always get runs that way.

If you get runs on vertical surfaces, you're doing it wrong. Apply several thin coats rather than few thick coats. Most products are fairly viscous and it's difficult to make a wet application that isn't too thick. The weight causes sags and runs.

Thin the product according to manufacturer's recommendation so you can apply a wet but thin coat.

Hanging vertically reduces the likelihood of dust settling on the surface. Also, the solvent released as the coating flashes can condense and fall onto horizontal surfaces if you don't have proper ventilation. These micro-droplets can cause tiny defects.

[col]

What is the best varnish to use?

Apparently, black varnish is best.

[newbe]

I have only done this once before and the finish is very good but lots of work.
I do not have a spray gun or compressor
Johnsons clear gloss varnish diluted with mineral spirit. never used Johnsons before but should be ok I hope.
I will be diluting polyurethane clear gloss varnish 50/50% and apply as wipe on then wire-wool first coat. second coat wipe on then wet and dry 1200 grit. Third coat wipe on then wire-wool. Fourth coat wipe on again wet and dry 2400 grit. Fifth coat see how its buffs up and if ok then finish, if not wet and dry 2400 grit then apply another coat and so on until finish is like glass.

[newey]

That sounds like a good plan, newbe. Just leave plenty of time in between coats and sanding/steel wool- days, not hours . . .

[reTrEaD]

Aug 16, 2021 13:51:14 GMT -5 newbe said:

I have only done this once before and the finish is very good but lots of work.
I do not have a spray gun or compressor
Johnsons clear gloss varnish diluted with mineral spirit. never used Johnsons before but should be ok I hope.
I will be diluting polyurethane clear gloss varnish 50/50% and apply as wipe on then wire-wool first coat. second coat wipe on then wet and dry 1200 grit. Third coat wipe on then wire-wool. Fourth coat wipe on again wet and dry 2400 grit. Fifth coat see how its buffs up and if ok then finish, if not wet and dry 2400 grit then apply another coat and so on until finish is like glass.

Hi newbe

I have no experience doing wipe-on finishes, so I'm unable to confirm your plan is valid. A couple of things seem unusual to me. Wire-wool of unspecified grade and the use of 1200 grit wet or dry sandpaper so early in the process. I'm accustomed to block sanding with 400 grit between the first two coats, 600 grit between later coats, then 1200 grit followed by polishing compound (if if any abrasives are necessary after the final coat). Then again, I use automotive products, sprayed on, and have never used more than 10% thinner.

Mineral spirits evaporate more slowly than Acetone or Lacquer thinner, so expect your flash times to be long.

Also, many of the Polyurethane products I've seen recommend Water as a thinner. But since this is a 'polyurethane varnish' perhaps mineral spirits is the correct thinner ... I don't know.

You said 'Johnsons'. Do you mean Johnstone's? That's a tradename used by PPG Industries for a line of coating products in the UK. Perhaps you can contact them and get recommendations for use of the exact product you'll be using?

Barring that, you might want to test your process on a large scrap of wood. That way, if there are any issues you can identify them before having a less acceptable coating on your guitar.

[thetragichero]

^^^^^ all good advice

[newbe]

thanks for the advice and I will follow them
Johnstones 309309 clear gloss is the product and its oil based so mineral spirit is being used.
I will try a test piece first.

[gckelloch]

Sorry to come late to the party. If you aren't invested in your plan, Tru-Oil makes a nice velvety-looking/feeling finish that doesn't crack. It takes ~20 coats to build up a deep rich luster, but no sanding is needed between coats and they can be applied in as little as 3 hours between each with a 1-week final curing. It's used on gun stocks and not available in California.

[newbe]

I have started a test piece and after the second coat its looking very good. the wood pores still need to be filled but I assume another two coats should do it. Johnstones varnish diluted and wipe-on is working well and will be carrying on for another 5 coats then see how it looks.
Sanding and wire wool is bringing up the shine as well but the sanding prior to varnish was the key, 2000 grid gave a very smooth wood finish. I do know that if used 600 grit and started varnishing then the varnish sinks in better as the pores of the wood are more open (the rougher the wood the better for the initial varnishing) but its the thin layers built up so I can still feel the wood quality and still have a very high shine. By the way I am in the UK so some varnishes are hard to get or not available in UK.
Thank you for all your help

[cynical1]

Yeah, I'm a bit scarce lately, but this one caught my eye.

First off, definitions. Varnish is merely the specific combination of resins, oils, and solvents. Originally, it was just tree sap and alcohol. Polyurethanes are the formula with a plastic resin added. Regardless of content, it still serves the purpose of protecting wood from contaminants. You can do this with shellac, lacquer, tung oil...etc. What finish to use is typically determined by the wood used, purpose of the finished piece and where it lives while performing said function...

I was interested to see you plan on reducing the varnish 50\50 and wiping. I've done necks this way with urethane for a long time and find it preferable to spraying them. You'll still need to hang them to dry, but as long as you're stingy with the application runs tend to be minimal. You will need to apply twice the number of coats, but that just makes sense. Wiping a gloss for 3-4 coats and then 2 final coats of satin, steel wooled after curing, will give you a very fast playing neck with a pop to the grain...

For the money and time, lacquer is a truly great finish for guitars. Sure, the sweat takes its toll over the years, but lacquer has an advantage that varnish doesn't...each successive coat "melts" into the previous one...thereby allowing seamless repairs and refinishes.

If you want a super high gloss mirror finish, lacquer is your best bet. I have gotten the best results with 600 grit wet or dry through 1500 grit. After that, just some rubbing and polishing compound followed by a swirl remover is all you need to get a mirror finish with lacquer.

This changes with varnishes, especially polyurethanes. They are designed to take abrasion, so buffing them out is an exercise in testing the theory.... You will never get the same shine much above the original on varnishes by buffing, as they are not designed to be polished out.

I have never been, and remain, no fan of any oil finishes on guitars...especially on the neck. Enough said on that one.

There's a lot more to it than that, but my fingers are getting tired...

Happy Trails

Cynical1

[gckelloch]

Aug 29, 2021 14:08:33 GMT -5 cynical1 said:

Yeah, I'm a bit scarce lately, but this one caught my eye.

First off, definitions. Varnish is merely the specific combination of resins, oils, and solvents. Originally, it was just tree sap and alcohol. Polyurethanes are the formula with a plastic resin added. Regardless of content, it still serves the purpose of protecting wood from contaminants. You can do this with shellac, lacquer, tung oil...etc. What finish to use is typically determined by the wood used, purpose of the finished piece and where it lives while performing said function...

I was interested to see you plan on reducing the varnish 50\50 and wiping. I've done necks this way with urethane for a long time and find it preferable to spraying them. You'll still need to hang them to dry, but as long as you're stingy with the application runs tend to be minimal. You will need to apply twice the number of coats, but that just makes sense. Wiping a gloss for 3-4 coats and then 2 final coats of satin, steel wooled after curing, will give you a very fast playing neck with a pop to the grain...

For the money and time, lacquer is a truly great finish for guitars. Sure, the sweat takes its toll over the years, but lacquer has an advantage that varnish doesn't...each successive coat "melts" into the previous one...thereby allowing seamless repairs and refinishes.

If you want a super high gloss mirror finish, lacquer is your best bet. I have gotten the best results with 600 grit wet or dry through 1500 grit. After that, just some rubbing and polishing compound followed by a swirl remover is all you need to get a mirror finish with lacquer.

This changes with varnishes, especially polyurethanes. They are designed to take abrasion, so buffing them out is an exercise in testing the theory.... You will never get the same shine much above the original on varnishes by buffing, as they are not designed to be polished out.

I have never been, and remain, no fan of any oil finishes on guitars...especially on the neck. Enough said on that one.

There's a lot more to it than that, but my fingers are getting tired...

Happy Trails

Cynical1

I'm glad you mentioned about oil finishes on necks. I'm making a Baritone "Jagcaster" and I was considering using some Tru-Oil to seal the roasted Maple neck, but I think I'll just stick with the periodic Howard Feed-N-Wax applications, which I've been using with success for a few years on all my bare guitar woods. It leaves a nice silky feel that doesn't get tacky.

I will go with Tru-Oil on the body just for the ease of application. I think the satiny patina and natural grain texture looks nice, and feel isn't really a concern for the body. I may want to fill the Black Limba grain with a dark green to match the Jade stone dot inlays on the neck. I need to find something Tru-Oil will stick too and not melt. So far, I'm thinking of just dying and sanding in either Tru-Oil or mineral spirits. I also want to use a lighter greenish dye over that b4 applying the clear Tru-Oil coats. I assume I'd also need to mix mineral spirits for that rather than water? I don't know much about finishes.

[sonikelectrik]

For what it worth, my 0.02. 

ReFinished my sons BCRich earlier this year and used a product called SprayMax 2K from Amazon. It’s a rattle can clear coat. It went on really well, really sticky, so even hung vertical for 360 coverage there were no runs. And no waiting around for thin wet drippy coats to dry before applying the next coat. 1 can did about a dozen thin coats n the body. He went with satin so I can’t say how well it polishes, but the recommendation I found do say it polishes up nice if that’s your thing. 

Nothings more convenient than a rattle can so this was a no brainer to try

hope that helps someone down the line

[gckelloch]

Sept 1, 2021 10:54:39 GMT -5 sonikelectrik said:

For what it worth, my 0.02. 

ReFinished my sons BCRich earlier this year and used a product called SprayMax 2K from Amazon. It’s a rattle can clear coat. It went on really well, really sticky, so even hung vertical for 360 coverage there were no runs. And no waiting around for thin wet drippy coats to dry before applying the next coat. 1 can did about a dozen thin coats n the body. He went with satin so I can’t say how well it polishes, but the recommendation I found do say it polishes up nice if that’s your thing. 

Nothings more convenient than a rattle can so this was a no brainer to try

hope that helps someone down the line

It helps me, as I don't really have the space to oil finish a guitar body over a week. Ace offers a 2K spray finish for ~1/4 the price of others. Wonder what the difference is?

[newbe]

Thanks for all the advice.
I have done a test piece using 50/50 mineral spirit and polyurethane. After 8 coats I have the finish I want and you can see your face in it and the wood grain is magnificent.
I have now started the guitar so this will take about a month to apply the finish and leaving the coats to dry hard before any rubbing down is carried out, about two days to dry before the next coat can be applied.
Word of warning, the fumes given off are chocking so a well ventilated area is essential.

[gckelloch]

Sounds good, but I think I'll go the 2K spray route for convenience. 2K is "catalyzed" polyurethane. It is a very tough and hard autobody finish used on many production guitars. Inhaling it can be deadly as it catalyzes in the lung, but I have an attic and a mask with filters. I think I will use it for the convenience. I can spray the body over ~4 hours and maybe even assemble the guitar the next day.

[sonikelectrik]

Yeah this stuff smells BAAAAD. I didn’t know about the catalyzing but I knew the small was bad from the reviews and that is clue enough. I had build a little heave to spray booth in my garage out of scrap wood and an old camping table cloth stapled to the side. That contained the over spray. And a box fan on high blew any spray out the open garage door. And I was wearing an N95 mask (itself a feat during the pandemic, remember all the hoarding)