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I will be finishing my first piece shortly. I have decided to purchase a mini-hvlp conversion gun because it should work with a smaller compressor and not nearly as expensive as an hvlp system. After grain filler and sanding up to 200 grit, what are my options of spraying a nice waterbase finish? I will be spraying outside/ in a garage and heard nitro can be explosive without explosion proof lights and fans.

Thanks

good ventilation and no ignition sources and it is relatively safe to spray nitro. explosions will not happen with out a source either active or reactive. I have sprayed several nitro finishes back before I had an explosion proof fan but I eliminated all possible sources if ignition. Wear an approved for volatiles respirator

Oh to address your topic title. I highly recommend KTM9 Clear Waterborne as an alternative to nitro. an uneducated finish person would be able to tell the difference if properly applied. It is my only available lacquer finish any more. Yes it is a bit softer than nitro but it is not a soft as everyone thinks about when thinking of waterborne finishes. I find no bluing and it is self cross-linking, non toxic or flamable

Also no matter which you use you need a .1mm-.15mm neddle and tip on you gun. min 40psi at 5cmf to operate the gun properly so be sure that your compressor will provide the air flow needed at least intermitenly best if continiously.MichaelP39008.6305787037

[QUOTE=MichaelP] an uneducated finish person would be able to tell the
difference if properly applied. .[/QUOTE]

That doesn't sound like much of an endorsement!

Did you mean that an educated finish person would be unable
to tell the difference, or that an uneducated finish person would unable to
tell the difference???

Mike

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Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

[QUOTE=SniderMike] [QUOTE=MichaelP] an uneducated finish person would be able to tell the
difference if properly applied. .[/QUOTE]

That doesn't sound like much of an endorsement!

Did you mean that an educated finish person would be unable
to tell the difference, or that an uneducated finish person would unable to
tell the difference???
Mike[/QUOTE]

It did sound wrong but what I meant was someone that is very familiar working with nito, will notice a slight difference but the general buying public will not. If you work with materials long enough you get very acquainted with their properties, if not you will not. That is what i meant by uneducated. Someone that is not experienced applying and working nito

KTM9 in my opinion is excellentMichaelP39009.4199537037

Ok, I see what you meant, Michael. Thanks for clarifying.

What do you think is the telltale sign for an experienced finisher that it's
different from nitro?

I'd love to do a waterbased finish instead of narsty solvents. It seems like
there's so many different opinions though

MikeSniderMike39009.444837963

_________________
Mike

"The Dude abides. I don't know about you but I take comfort in that. It's good knowin' he's out there. The Dude. Takin' 'er easy for all us sinners. Shoosh." The Stranger

Nitro has no noticeable tint to the film it's self. depending on the lighting you are working under It may appear very very very slight amber hue. All waterborne have a very slight blue tint. KTM9 has the least of any I have worked with. So slight that you almost have to be in blueish fluorescent lighting to even tell. Nito has a different feel to it but then again you have to work with a while to understand what I mean.

I am probably going to get my self in trouble here. but most non-approving opinions I have read about KTM9 came from users that either had problems applying the finish (not the product fault but in experience using it) or from those with a bias against waterborne in the first place. prior to the latest generations of waterborne lacquers tint and witness lines were real issues. Hardness I believe will always be less than Nitro but KTM9 is hard enough to provide a quality finish. MichaelP39009.4673726852

I have both nitro and KTM-9 at home and I want to try different tests... I will be posting pictures soon...

I have seen a KTM-9 finish on one of BobC's guitars (the zootmeister) and the finish was excellent!

If it's properly applied, the results will be outstanding.

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

The posts have been very informative. Would the ktm9 be sprayed and finished in the same fashion as nitro or are the procedures different? I look forward to the pics!

Folks,

See the December 2006 "Fine Woodworking" issue. 13 different water-based finishes were reviewed. The gist of the article is that water-based finishes have come a long way, few exhibit the "blue" tint common in these finishes only a few years ago and they are easy to apply and some are quite hard. Quite a range of performance and color/clarity/sandability, etc. Worth checking out? Dunno. Can't say how these would work on a guitar.

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"Building guitars looks hard, but it's actually much harder than it looks." Tom Buck

This is a brief breakdown of my schedule

3-4 coats per day. Allow to cure for 24 hours. Level lightly. 3-4 coats a day for the second session. level lightly. 2 final coats allow to cure 2 weeks-30 days. Final level and buff.

That is a 8-10 total coats.MichaelP39009.6221527778

Oh I should have also said that after the light leveling I always spray a light coat of DA and allow to flash off before I start that days KTM spraying. This helps the new coats crosslink the best.

What is DA and flash off?

DA is Denatured Alcohol and flash off is the evaporation of the DA

I can't tell from your post if you have spraying experience or not, but since you plan to buy a hplv conversion gun I'm gonna assume you have non to little.. And heres why,,, I did the same thing.. I had sprayer before,, once or twice, but went out and got an astro mini hplv gun,, and put KTM9 on a maple dulcimer. When I practiced on scrap maple, i did not like the finish since it was so clear. In other words the maple did not have a wet look, it just was shiny.. I had decided to seal the maple with epoxy just to get the darked wet look then shot KTM9 in a schedule similiar to MichaelPs above. Now, as I said,, I'm not even at amatuer level,, one or two steps before that.. After curing, leveling and buffing I am thrilled with it. It is clear and mirror like. And overall i thought fairly easy to accomplish too.
Mike

Thanks for the message. I've played with an hvlp spray gun a few times but thats the extent. I am also looking at the mini atro. I'd probaby benefit greatly if you went through the schedule in specific detail. Do you mind?

I have been told 2 different things about thinning the KTM 9.
1) Always use DA, never use water to thin it out..and
2) Always use Distilled water, never use DA to thin it out.
Is either one a particularly better way to go?
What gives?
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

I second the suggestion to read the FWW article on waterbased finishes.

_________________
Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

A slightly different opinion....
I was probably the first person to use KTM-9 as a guitar finish, but I probably won't be the last to stop using it...
While it's an easy finish to use and spray, too many people have had too many issues with it being too soft. A lot of folks have switched away to other things, including me. It is no longer my finish of choice. There was a recent thread on the newer Target Coatings product awhile back, and I will probably give it a try for projects where I'll want to spray myself. Otherwise, I will farm out my future work.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Why do some thin Ktm9? It is at a good spraying viscosity straight out of the can.

I recently had a KTM- finished guitar come back to me with orange-peeling of the finish where the owner's thumb rested in first position. I am going to strip the neck and put on an oil finish. No problems with the body so far.
I have finished my last two instruments with the Stew-Mac Target product. It sprayed, sanded and buffed beautifully. Both were EI rosewood,and have a noticably bluish cast on the body, although not on the spruce tops. I thought I had applied it too heavily on the first try and used fewer and thinner coats on the second, to no avail. It is also rather soft as many have noticed.

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In Markham,Virginia

If this happened then the film was not cured, sprayed on too heavy or in a too humid enviroment and never will cure. Target will do the same thing if sprayed too heavy. In fact any finish will do this. Ktm9 is not to fault here. I have used Stewmac Colortone many times as well it is a good product. to me it does not dry as hard as Ktm9 (when properly applied) but is hard enough. The one area I can confirm a big difference in is tint. The Colortone always has a slight blue tint to the film. Some say they can see a less prevalent blue tint in Ktm9 but I can't and I keep looking. Both are great products.

If you follow Mike Dooling's schedules you will not get a blueish tint to the film of Ktm9 and it will cure fully. But like I said, if not applied in the proper manner and humidity, any finish will not cure properlyMichaelP39013.6954282407

Perhaps the key here is you are finishing your first piece and want some advice. I have only completed 12 guitars and consider myself a beginner and have finished nine guitars with Tru-Oil (and they look very nice but have a very soft finish).

I purchased an HVLP conversion gun and a 3HP, 15 gallon compressor. Set at 50psi, I used StewMac's Water Based Lacquer and sanding sealer and clear grain-filler. I followed their informatiomn sheet directions to spray a spruce and maple steel string guitar and it came out beautifully. I was shocked that my first spray project looked so good! I see no blue tinting and it seems like a very hard finish although only time will tell.

Now I got overconfident and tried nitro on #11. I used an approved respirator mask and goggles and waited till the humidity dropped (I live in Tampa), and sprayed in my garage with the double garage door wide open. This was a mistake! I was overcome by the fumes and my wife complained about the house smelling like lacquer! I stopped this and went back to the water based lacquer to spray a rosewood and spruce steel string. Again, I really like the results.

So as new builders, maybe we should start simpler and have success and then graduate to a real spray booth at a later date.

It was interesting to me that the FWW article did not include KTM-9 or Target products. I have zero experience with waterborne finishes myself. I wonder, though, with all the various manufacturers competing to produce good waterbase finishes these days, if some of these might be as good or better than KTM-9 or Target, which are the only two I ever hear guitar makers talk about. The FWW review of the best products they tested was extremely positive in all regards -- durability, clarity, ease of application, etc.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Turbo411, a couple of things to remember if you decide to use KTM-9...
KTM-9 is a "water-white type of finish. In order to bring out the darker
tones and grain in the wood you will need to use some kind of sealer or
tint under the KTM-9. Epoxy has been recommened. I've been using
shelac as a under coat/sealer and I'm pretty happy with it. Also! blue
masking tape is VERY reactive with KTM-9! Even a few seconds of contact
and the finish becomes pitted.... The brown masking tape doesn't seem
to bother......

It's nice that the water based stuff won't blow-up and, it doesn't stink!
Either the KTM-9 dosn't have a smell or the nitro has ruined my sense of
smell?

Oh, Yeah, I'm new here, I missed being #1000 by 2   

longBob Long39013.8674189815

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"No man ever steps in the same river twice, for it's not the same river and he's not the same man.” -Heraclitus of Ephesus