Best Conversion Varnish???

[Rôckhewer]

Hi there happy Luthiers!
I'm a woodworker by trade, but finishes are not my forté.
(we use Danish oil on the specific products we make at my shop)
I am convinced that I want to use a high build Conversion Varnish on my current build.
I want a deep gloss coating that is hard and crystal clear... But that dries quick, builds quick & thick... and can be sanded and buffed out....quicker than nitro that's for sure...
It makes alot of sense that such a finishing product would be post catalyzed...(if that's the right term for : I add the catalyst)
And everything I've read about CV makes me feel like it is exactly what I want.

Questions:
Which brand/type/formulation....etc... Should I use??
And where do I find it??
And how much should I need for just one bass.??

Thanks in advance for any knowledge anyone is willing to share

P.S. I'm in Arizona & it is starting to get hot.
But I have evaporative coolers in my shop....so it's about 80° in the spray booth....

 

[wraub]

Hey, it's only supposed to be 106 today...

 

[Bruce Johnson]

I'm using Varathane Water-Based Floor Varnish on all of my instruments these days. It has the perfect characteristics, in my experience. Very fast drying, completely clear, very hard and tough, easy to dry-sand and buff up to a high gloss, and fairly easy to spray.

Much more info about it in this thread:
Using water based products for instrument finishing, Target Coatings 9000 6000 and Varathane WB | TalkBass.com

A companion product is Varathane's 3X water-based varnish. It's very thick, made for brushing on. It dries hard, fast, and is easy to sand. It makes a great base "sanding sealer" under the Varathane Floor Varnish.

 

[Rôckhewer]

P

I'm using Varathane Water-Based Floor Varnish on all of my instruments these days. It has the perfect characteristics, in my experience. Very fast drying, completely clear, very hard and tough, easy to dry-sand and buff up to a high gloss, and fairly easy to spray.

Much more info about it in this thread:
Using water based products for instrument finishing, Target Coatings 9000 6000 and Varathane WB | TalkBass.com

A companion product is Varathane's 3X water-based varnish. It's very thick, made for brushing on. It dries hard, fast, and is easy to sand. It makes a great base "sanding sealer" under the Varathane Floor Varnish.

Bruce,
Thanks for responding to my question.
Do any of the water based products that you use need to be catalyzed?

I didn't get very far reading that thread when I saw this:

With water based topcoats applied to wood alone, the grain does not pop, and darker woods look pale and pasty. To counter that problem, one must "pop" the grain with some sort of oil based product or shellac.

Have you had this problem /effect?
Or should I just keep reading the thread....

 

[Bruce Johnson]

P
Bruce,
Thanks for responding to my question.
Do any of the water based products that you use need to be catalyzed?

No, none of these finishes need to be catalyzed. That's one of the great things about them. They are "cross-linking", which I understand to mean that they self catalyze as soon as enough of the water carrier evaporates. The Varathane, in particular, is amazing stuff. It dries rock hard in a few hours. I've actually been able to sand it an hour after spraying, when needed. It's ready for final level-sanding and buffing in 6 hours.

P
I didn't get very far reading that thread when I saw this:
Have you had this problem /effect?
Or should I just keep reading the thread....

I'm not sure that I see this as a problem. These water-based finishes like the Target EM9000 and the Varathane Floor Varnish are almost perfectly clear. That is, they have no built-in tint. Most traditional oil-based finishes have an inherent amber tint. So, if that's what you are used to, then these water-based finishes will appear bluish and won't pop the grain. Well, yeah, that's because they are clear. If you want tint, you add some amber tint to the Varathane. Not a big deal. You can add as much as you want, in whatever shade you want. You don't need to use some other kind of finish underneath it, just to get the amber tint.

 

[Rôckhewer]

To me.... It has more to do with light & surface reflectivity than anything else. Its like....if I flood the surface of the wood with mineral spirits, that wet look is what I'm interested in because the light is able to get into the wood and reflect off the natural chatoyant nature of the curl.
So you think that by "popping the grain" they mean that the amber coloring in oil, for instance, is depositing in the end grain of the curl and creating some of the shadowing effect that occurs... Like when a trans tint is applied /sanded back....etc...?

 

[Hopkins]

To me.... It has more to do with light & surface reflectivity than anything else. Its like....if I flood the surface of the wood with mineral spirits, that wet look is what I'm interested in because the light is able to get into the wood and reflect off the natural chatoyant nature of the curl.
So you think that by "popping the grain" they mean that the amber coloring in oil, for instance, is depositing in the end grain of the curl and creating some of the shadowing effect that occurs... Like when a trans tint is applied /sanded back....etc...?

Whatever the stuff @Big B. is using is probably a really good place to start as he gets fantastic results with it. Other than that I cant help much, as I am a 2k Urethane guy. If you decided to go with a 2k, Shopline JC60 is about $80 a gallon with a quart of hardener included. It works very well. Shopline is a lower line of PPG

 

[Bruce Johnson]

Yes, that's exactly what "popping the grain" is. You use some kind of a dark tinted relatively thin (low viscosity) finish. The idea is that it will sink into the end grain, but be rubbed or sanded off of the harder side grain. This creates a shaded contrast which brings out the 3-D effect of the figured wood.

This can be done several ways:

You can apply a thin dye (like Trans Tint) directly to the bare wood. This gives the most dramatic effect, but it's also the most dangerous. It's real hard to control the darkness, and easy to get uneven blotches. And the dye sinks deep into the wood. It can't really be corrected without heavy sanding.

A variation of that is to first apply a thin coat of thinned (low viscosity) clear shellac to the bare wood. Then apply the dye over the shellac. The shellac sinks into the wood and creates a barrier that prevents the dye from sinking in too deep.

Another popular method is to use a tinted, fairly thin finish, wiping it on the bare wood. For example, mix some amber dye into some of the clear Varathane. Wipe that onto the bare wood, pushing it into the end grain and wiping the excess of the side grain. Because it's thicker (in viscosity), it's a more controllable process. The dye is suspended in the finish. It's easier to get it even.

Or, you can tint the Varathane (or other finish) and spray it onto the bare wood. Let it dry and gently sand it back, leaving the dark end grain, but cleaning the tinted finish off of the side grain.

All of these methods are different ways of "popping the grain". They all must be done starting on bare wood They won't work if the grain has been filled and sealed.

After the grain is popped, you continue on with the rest of the finish. It can be clear or tinted, depending on what you want.

 

[Rôckhewer]

Yes, that's exactly what "popping the grain" is. You use some kind of a dark tinted relatively thin (low viscosity) finish. The idea is that it will sink into the end grain, but be rubbed or sanded off of the harder side grain. This creates a shaded contrast which brings out the 3-D effect of the figured wood.

This can be done several ways:

You can apply a thin dye (like Trans Tint) directly to the bare wood. This gives the most dramatic effect, but it's also the most dangerous. It's real hard to control the darkness, and easy to get uneven blotches. And the dye sinks deep into the wood. It can't really be corrected without heavy sanding.

A variation of that is to first apply a thin coat of thinned (low viscosity) clear shellac to the bare wood. Then apply the dye over the shellac. The shellac sinks into the wood and creates a barrier that prevents the dye from sinking in too deep.

Another popular method is to use a tinted, fairly thin finish, wiping it on the bare wood. For example, mix some amber dye into some of the clear Varathane. Wipe that onto the bare wood, pushing it into the end grain and wiping the excess of the side grain. Because it's thicker (in viscosity), it's a more controllable process. The dye is suspended in the finish. It's easier to get it even.

Or, you can tint the Varathane (or other finish) and spray it onto the bare wood. Let it dry and gently sand it back, leaving the dark end grain, but cleaning the tinted finish off of the side grain.

All of these methods are different ways of "popping the grain". They all must be done starting on bare wood They won't work if the grain has been filled and sealed.

After the grain is popped, you continue on with the rest of the finish. It can be clear or tinted, depending on what you want.

Thanks for all those different ways to achieve a popped look.
But I was just trying to decide whether I even needed to go to such measures to get a deep definition of the curl on my bubinga top... And if my understanding of a plain clear gloss finish is correct....
Like I said:....
It has more to do with light & surface reflectivity than anything else. Its like....if I flood the surface of the wood with mineral spirits, that wet look is what I'm interested in because the light is able to get into the wood and reflect off the natural chatoyant nature of the curl.
Here's a pic of my top wood after wetting with mineral spirits. All the lighter color is actually very shiny / chatoyant / or curly grain.

 

[Big B.]

I've been using the Sherwin Williams conversion varnish branded as Sher-Wood. The finisher at my shop is one of the most respected in the Austin area and it's what we use for our finishes. So far I have found it fairly easy to work with though I suggest a trial run on another project before you spray a guitar.

 

[Bruce Johnson]

Thanks for all those different ways to achieve a popped look.
But I was just trying to decide whether I even needed to go to such measures to get a deep definition of the curl on my bubinga top... And if my understanding of a plain clear gloss finish is correct....
Like I said:....
It has more to do with light & surface reflectivity than anything else. Its like....if I flood the surface of the wood with mineral spirits, that wet look is what I'm interested in because the light is able to get into the wood and reflect off the natural chatoyant nature of the curl.
Here's a pic of my top wood after wetting with mineral spirits. All the lighter color is actually very shiny / chatoyant / or curly grain.

When you pour the mineral spirits on, it quickly evaporates off of the hard side grain, making it lighter in color, while it stays soaked into the end grain longer, keeping it dark. That's why you get the contrast in lighter vs darker tones, for a few minutes. It isn't surface reflectivity. Look at the picture. It's the same effect that you are trying to get with the "popping" methods; darkening the end grain. Just putting a clear finish on there won't do that.

 

[Rôckhewer]

Thanks.
Makes sense.
I just read that entire thread and learned quite a bit.
I hope the WB varathane floor...is better than the OIL base varathane in the rattle can...
Cause I tried that on another bass, over Danish oil that was cured for about a week. It seemed very soft ...it had sufficient cure time to be sanded...but it was just generally soft crap.

Anyway...what I wanted to ask was what type of buffer you use?

I understand polishing....lots of different materials. I was a granite & marble fabricator for years.
I understand buffing compounds etc...
And.. I have done automotive paint ...(wet sanding/ buffing out clear coat).

But I have never buffed out clear coat polyurethane on wood.

So exactly what type of buffing apparatus are you using to get a gloss finish...
Cotton, muslin, felt...? Arbor type... Loose sewn...etc...? Or some kind of bonnet type...? Like on an automotive buffer?

 

[Rano Bass]

I've been using the Sherwin Williams conversion varnish branded as Sher-Wood. The finisher at my shop is one of the most respected in the Austin area and it's what we use for our finishes. So far I have found it fairly easy to work with though I suggest a trial run on another project before you spray a guitar.

Are there any special settings on the spray gun needed to spray conversion varnish? I want to experiment with it but first I want to learn a little bit about any learning curves to avoid.

 

[Bruce Johnson]

Thanks.
Makes sense.
I just read that entire thread and learned quite a bit.
I hope the WB varathane floor...is better than the OIL base varathane in the rattle can...
Cause I tried that on another bass, over Danish oil that was cured for about a week. It seemed very soft ...it had sufficient cure time to be sanded...but it was just generally soft crap.

Anyway...what I wanted to ask was what type of buffer you use?

I understand polishing....lots of different materials. I was a granite & marble fabricator for years.
I understand buffing compounds etc...
And.. I have done automotive paint ...(wet sanding/ buffing out clear coat).

But I have never buffed out clear coat polyurethane on wood.

So exactly what type of buffing apparatus are you using to get a gloss finish...
Cotton, muslin, felt...? Arbor type... Loose sewn...etc...? Or some kind of bonnet type...? Like on an automotive buffer?

(Also posted on the WB finishes thread)

I use two different buffing methods.

1.) My Scroll Bass necks have lots of intricate curves and delicate areas. So I usually clamp them down stationary to the bench in holding fixtures. I do the buffing with a hand held variable speed electric drill, using various buffing wheels mounted on 1/4" arbors. Most commonly used are 6" dia loose sewn cotton buffing wheels. I use them single-stack (nominally 1/2" thick), and I have some that I've trimmed down to be thinner. I also have some smaller diameter ones to get into tighter areas. I keep different wheels for the different grit compounds. The drill has a keyless chuck, so it's real quick to swap them. I run the drill at 500 to 1500 rpm, depending on where I'm polishing.

2.) On larger-area parts like bodies, I hold the parts by hand in front of a stationary buffer. The buffer is a motor driven horizontal spindle. You can buy or build them. Mine is an unusual machine which has quick-change spindle shafts. I made up one spindle for it which has a keyless drill chuck in the end. So, it will take any of the same arbor-mounted buffing wheels that I use in the electric drill. It's really handy to be able to rapidly switch a variety of different wheels between them.

The stationary buffer has two speeds, 1750 and 3450 rpm. For buffing finishes, I use 6" or smaller wheels at 1750 rpm. At 6" dia and 3450 rpm, it generates too much heat, and it's too easy to melt the finish. I use the higher speed, with different wheels of course, for polishing metal parts.

Besides the loose sewn cotton wheels, I use some of the wool dome-style buffing pads too. I found some which are made with a 1/4" arbor. They work well for large areas, like backs of bodies.

In general, for buffing these water-based finishes, you want to run approximately 6" wheels or pads at 500-1750 rpm. Whatever your setup, you need to have a really good feel for the amount of pressure you are applying. In most cases, these finishes that we are applying to our instruments are much thinner that a typical automotive finish, and they can't disperse heat well through the wood. So you need to have a delicate feel to avoid building up heat and melting the finish. That's why the variable speed hand-held electric drill is my favorite for doing the intricate areas.

You can use either the electric drill or the stationary buffer for the entire instrument. Each has their pros and cons. I use both.