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  #16  
Old 02-14-2018, 07:08 PM
LouieAtienza LouieAtienza is offline
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Originally Posted by charles Tauber View Post
None that I've used. The latest I've used are Target 6000 and 7000: you don't want to sand through them, else you'll have witness lines.
I was trying to be careful in my wording. Didn't intend to convey that that subsequent layers would meld with the existing. Rather that subsequent layers react as such to previous ones that there is a chemical bond formed, not simply a bond due to abrading the surface or such. From woodweb:

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A qualifying waterborne lacquer will exhibit good to excellent clarity, good to excellent chemical resistance and a high degree of burn-in, or remulsifying capabilities when layered upon itself, or upon a coating that will allow the solvent structure of this film to chemically attach itself to the wb lacquer, much like a solvent-based lacquer. Generally, an acrylic system is used to create this film-forming agent due to their ability to remulsify into themselves when the appropriate co-solvents are used to promote platicization and coalescing.
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  #17  
Old 02-15-2018, 07:43 AM
Ned Milburn Ned Milburn is offline
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Originally Posted by LouieAtienza View Post
Not with waterborne lacquers.. they are designed to cut in, at least as i understand it.
As I understand it, once water-based finishes cure, they don't cut in. And this is consistent with my limited experience with water based.
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  #18  
Old 02-15-2018, 08:23 AM
LouieAtienza LouieAtienza is offline
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Originally Posted by Ned Milburn View Post
As I understand it, once water-based finishes cure, they don't cut in. And this is consistent with my limited experience with water based.
Like a catalyzed urethane finish (which is whay I use) you spray the first coat, allow it to "set up" so to speak, then spray a flash coat on top. Because they're usually high solids cintent you don't have to build it like nitro lacquer. Also waterborne works best with HVLP system, where nitro is usually sprayed with high pressure conventional guns...
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  #19  
Old 02-15-2018, 08:51 AM
redir redir is offline
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Maybe that was my problem all along as I used to brush waterborne on. But then the KTM that LMI sold back in the day had instructions on using foam brushes. Brushing probably requires more aggressive sanding and as such I have gone through the layers more times then I care to remember. But still, my guess is that it's nothing like the chemical melting properties of Nitro.
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  #20  
Old 02-15-2018, 10:01 AM
LouieAtienza LouieAtienza is offline
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Originally Posted by redir View Post
Maybe that was my problem all along as I used to brush waterborne on. But then the KTM that LMI sold back in the day had instructions on using foam brushes. Brushing probably requires more aggressive sanding and as such I have gone through the layers more times then I care to remember. But still, my guess is that it's nothing like the chemical melting properties of Nitro.
If brushing, I've had luck adding a little Floetrol (ir Penetrol if oil finish). Helps it flatten out a little better. I think brush works better, but the idea is not to brush the finish on, but let it flow off the brush.
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  #21  
Old 02-15-2018, 10:08 AM
Alan Carruth Alan Carruth is offline
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My understanding is that wb finishes are emulsions; microscopic droplets of finish, with a minimal amount of solvent, suspended in water by use of an emulsifier. This is the general scheme of mayonnaise, and Titebond glue. With the limited amount of actual solvent they should have some limited ability to 'burn in', which will depend a lot on the finish, the solvent, and the emulsifiers used.

My experiences with water borne finishes has been uniformly negative, although I admit it was also some years ago. I hope they have made improvements.

At the moment I'm using an oil-resin varnish; Murdoch's Urealkyd-500 floor varnish, made by Sutherland-Welles in Vermont. They use tung oil and resins produced from the waste products of the Cabot cheese plant. They also employ a citrus-based solvent. It has it's drawbacks, but I'm learning to work with it. As such things go the witness line issue is minimal, and it can be touched up to some extent. It's almost as hard as nitro. The main issue has to do with curing on some oily woods, with part of the problem being that it doesn't always sort out by species. Fortunately, this stuff is fully compatible with CA, which can be used to stop out areas, such as ebony fingerboard edges, that are problematic.

Everybody is looking for the 'perfect' finish. It doesn't exist. All you can do is find the one that has the qualities you need and drawbacks you can live with.
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  #22  
Old 02-15-2018, 10:24 AM
LouieAtienza LouieAtienza is offline
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Originally Posted by Alan Carruth View Post
My understanding is that wb finishes are emulsions; microscopic droplets of finish, with a minimal amount of solvent, suspended in water by use of an emulsifier. This is the general scheme of mayonnaise, and Titebond glue. With the limited amount of actual solvent they should have some limited ability to 'burn in', which will depend a lot on the finish, the solvent, and the emulsifiers used.

My experiences with water borne finishes has been uniformly negative, although I admit it was also some years ago. I hope they have made improvements.

At the moment I'm using an oil-resin varnish; Murdoch's Urealkyd-500 floor varnish, made by Sutherland-Welles in Vermont. They use tung oil and resins produced from the waste products of the Cabot cheese plant. They also employ a citrus-based solvent. It has it's drawbacks, but I'm learning to work with it. As such things go the witness line issue is minimal, and it can be touched up to some extent. It's almost as hard as nitro. The main issue has to do with curing on some oily woods, with part of the problem being that it doesn't always sort out by species. Fortunately, this stuff is fully compatible with CA, which can be used to stop out areas, such as ebony fingerboard edges, that are problematic.

Everybody is looking for the 'perfect' finish. It doesn't exist. All you can do is find the one that has the qualities you need and drawbacks you can live with.
On some oily woods like cocobolo, I'd put a coat of shellac on first. Sticks to oily wood, and oil finish sticks to it. I spray it on however, so that I don't discolor any surrounding wood.

Does that varmish have a cheddar scent?
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  #23  
Old 02-15-2018, 10:25 AM
charles Tauber charles Tauber is offline
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Originally Posted by Alan Carruth View Post
My experiences with water borne finishes has been uniformly negative, although I admit it was also some years ago. I hope they have made improvements.
Most of my experiences with water borne finishes haven't been great. Target 7000 was a total disaster, and seems to have been discontinued. Target 6000 worked very well sprayed, HVLP. Ned brushes it on with good results.


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Everybody is looking for the 'perfect' finish. It doesn't exist. All you can do is find the one that has the qualities you need and drawbacks you can live with.
Very true. For me it's the one I hate least.

I recently finished a table top with a solvent-based wipe-on poly. Easy to apply, looks good, very resiliant, hard to screw up, but smells awful and produces headaches, out-gassing for weeks. I haven't tried it on instruments, but it would probably be a viable finish along with Fred's build with hand tools for beginners.
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  #24  
Old 02-15-2018, 03:11 PM
redir redir is offline
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Originally Posted by LouieAtienza View Post
If brushing, I've had luck adding a little Floetrol (ir Penetrol if oil finish). Helps it flatten out a little better. I think brush works better, but the idea is not to brush the finish on, but let it flow off the brush.
That is the skill of the master. It's something you read in books on how to apply finishes but I'd swear it takes a decade to learn.

I'm not sure what the stuff was but there was something I added to the finish that made it flow better for brushing. It definitely helped but I could never get it right.

Incidentally I had a guitar come back into my shop for a bridge repair that was going on 15+ years old and was finished with KTM and it looked terrible. I really wanted to refinish the guitar for the customer but fortunately he liked the tone of it so much he was willing to live with it.
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  #25  
Old 02-15-2018, 05:02 PM
Wozer Wozer is offline
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Quote:
Originally Posted by LouieAtienza View Post
Like a catalyzed urethane finish (which is whay I use) you spray the first coat, allow it to "set up" so to speak, then spray a flash coat on top. Because they're usually high solids cintent you don't have to build it like nitro lacquer. Also waterborne works best with HVLP system, where nitro is usually sprayed with high pressure conventional guns...
??

I sprayed my first things with a conventional gun about 20 years ago...then had a big project where the savings in materials by using a Binks Mach1-SL paid for the gun, so I got it and can't be happier...less wasted material floating away into the exhaust (and of course tending to get on the project in a negative way) and a smoother finish.

can't say I understand where you are getting the concept that lacquers are usually sprayed with a conventional gun. admittedly the Mach1 is a conversion gun, still...point being I know of loads of people using HVLP systems for lacquers
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  #26  
Old 02-15-2018, 05:11 PM
Shuksan Shuksan is offline
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Originally Posted by charles Tauber View Post
None that I've used. The latest I've used are Target 6000 and 7000: you don't want to sand through them, else you'll have witness lines.
I've been using EM6000 for six years and have had the "opportunity" a few times to repair sand through and a couple chip outs. There were no witness lines and the repairs were invisible. Maybe the product has improved.
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  #27  
Old 02-17-2018, 02:52 PM
LouieAtienza LouieAtienza is offline
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Originally Posted by Wozer View Post
??

I sprayed my first things with a conventional gun about 20 years ago...then had a big project where the savings in materials by using a Binks Mach1-SL paid for the gun, so I got it and can't be happier...less wasted material floating away into the exhaust (and of course tending to get on the project in a negative way) and a smoother finish.

can't say I understand where you are getting the concept that lacquers are usually sprayed with a conventional gun. admittedly the Mach1 is a conversion gun, still...point being I know of loads of people using HVLP systems for lacquers
Well, I had a cabinet shop about 8 years before your experience with that Binks. I had a 2001 and Model 7. At the time, these were great guns. The HVLP stuff at the time gave us trouble with not enough volume of lacquer in the mix. We'd switch to a larger nozzle and had issues with orange peel. We even tried a turbine system, but the turbine produced heat in the air that make spraying lacquer tricky. For waterborne finishes they worked better for us, because those finishes stayed wetter longer.

Of course technology had increased immensely since my first experiences, and with new regulations and the crazy cost of coatings nowadays it has for the better. I have a FINEX conversion gun now that works well, though my Home-Cheapo touch up gun has a finer atomization, and leaves a smoother finish.
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  #28  
Old 02-17-2018, 06:24 PM
Alan Carruth Alan Carruth is offline
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LouieAtienza asked:
"Does that varmish have a cheddar scent?"

Nope; smells like citrus when you open the can, and varnish later on.

I tried stopping out with shellac; didn't work very well. CA is better with this stuff. It also has a closer refractive index to the varnish, so it doesn't look 'veiled', and is a bit harder than shellac, and closer to the varnish in that respect.
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  #29  
Old 02-18-2018, 12:28 PM
LouieAtienza LouieAtienza is offline
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Quote:
Originally Posted by Alan Carruth View Post
LouieAtienza asked:
"Does that varmish have a cheddar scent?"

Nope; smells like citrus when you open the can, and varnish later on.

I tried stopping out with shellac; didn't work very well. CA is better with this stuff. It also has a closer refractive index to the varnish, so it doesn't look 'veiled', and is a bit harder than shellac, and closer to the varnish in that respect.
I'll have to try the CA. CA does react with the oils in the wood and hardens them, which I think is a good thing; many cuemakers use CA to finish oily woods.
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  #30  
Old 02-19-2018, 03:23 PM
jessupe jessupe is offline
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I could literally go on for days about this subject. I have years of experience working with chemical companies "test driving" different coatings for their industry. This "side work" came from years of sanding and finishing hardwood floors, through this experience I came to work with many of the lead chemist's for many of the top finish companies, Loba international,Bona, Sherwin Williams, RPM, Betco, Quaker Color to name a few, and through this work and experience, I came to understand a couple of things.

1. virtually every chemical solvent is detrimental to your health
2.you are being used as a guinea pig
3.while many of these formulas work, barring msds sheets and known chemical interactions with the human body, these people have no idea of what the long term exposure consequences are. What ever they are, they will be minimized on the lables.

About waterbase finish, and absolute chemical crap shoot.

Carbodomide, Isocyante, Poly Functional Azridine are the primary catalyst's used in waterbase finish. Everyone of them is a sensitizer to both skin and lungs, so great less VOC offgasses into the atmoshphere, but you now get to play russian roulette with your health based on chemical companies being mandated to drop voc levels. Emulsion finishes which use simple oxygen crosslinking to dry often times use glycol esters in order to bind oil/water solvents together, they are seriously nasty chemicals, most 1 part waterbase finishes have just as bad of chemical stews as the 2 pak, Methyl pyrrolidone and Triethylamine are not "happy" chemicals for example.

at any rate I would sum this up as this, what I learned over all my years was this;

The best varnishes in the world were created/ "invented" in the 1400's, perhaps earlier. These are the varnishes that modern chemistry basically went to war against and had a massive propaganda campaign against.

These varnishes were sold to you as "inferior" when compared to the varnishes that "modern chemistry" has created for you, an absolute lie sold to yo by the petro chemical industry who had no other goal than to be able to use and sell the byproducts from petroleum.

Again the "ancient" varnishes beyond being much safer, as the solvent is turpitine, are far superior in so many ways that its not even funny. The primary advantages of the ancient varnishes are.

1. chemical saftey compared to other solvents
2. durability, these are the varnishes that are applied to "Italian" violins and other wooden objects . Many of these violins are pushing 4-500 years old and still have perfect varnish that not only has remained stable {no chipping, peeling, checking, cracking } over this extended period of time, but most importantly, the solids once converted in the cooking process remain absolutely transparent after all this time.
3. these varnishes refractive indexes are the most similar and or transparent to natural wood, therefore any chatonoyance in wood grain will be celebrated more so than with other solid bases

These varnishes primariliy use 3 simple ingredients, Linseed oil, Turpintine, and various Conifer resins. This is advanced alchemy that uses some very cool tricks in the cooking process to infuse minerals and metals into the varnish that once cooked, bind all compounds into an irreversible formula to make a varnish that will remain stable and transparent for hundreds of years.

These varnishes can be purchased, or they can be made and perfected by one at home with some basic precautions.

Basically if I could sum it up; the entire modern coatings industry is a lie that revolves around profit and a bunch of early propaganda that was instilled in order to make these varnishes I'm talking about go "byebye".

And I would say that they were very successful at driving people away for using, understanding or wanting these old formulas. They were very good at making you think that old stuff sucks and this new "better living through chemisty" products are better, the proof of this is somewhat in the pudding in that in the entire world there are a mere handful of people who manufactuer these linseed,turp,pine sap varnishes.

The other very appealing thing about these old world varnishes is their application benefits.
1. touch ups can be done without leaving a shorline {things blend and become invisible, you can;t tell where the touch up was done
2. Thick looking, but absolutely the thinnest layers can be applied.

These products are applied by hand, and when I say hand, I mean HAND. You take a brush, dip in the varnish, pat some finish blobs on the work, then with a raw hand, you quickly swirll and smear the varnish on to the wood. Then simply pat it out, it has self leveling properties that rival oil modifiesd urethane, so it lays down super thin but also drys very even.

I would encourage anyone who does their own varnish to look into it, not only does it provide a superior final product, but it is much, much safer to use.
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