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Here's an example of what I ended up with. This was level sanded with P600 then I shot 2 coats of PolyWhey thinned with about 5 to 10% distilled water. After drying for 6 days I final sanded with P1000, P1500, and P2000. Final sanding was wet with mineral spirits. Finally I polished with Novus #2 and buffed with an ROS buffer pad. I don't have a buffer yet. I'm plenty happy with the gloss - as good as I ever got with EM6000, fewer coats, and less work.

I could see some witness lines when I started final sanding but they seem to have vanished - for now Also, the drop fills that I did are completely blended in.

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Steve Smith
"Music is what feelings sound like"

How many coats total?


Sent from my Nexus 7 using Tapatalk 2

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Formerly known as Adaboy.......

7 coats total IIRC. I'll check my notes tomorrow and write down the finish schedule I used; it was pretty typical for a waterborne finish though.

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Steve Smith
"Music is what feelings sound like"

OK...you've convinced me. I ordered some to try. I have long been looking for a non toxic.

Steve, how much product did it take to do a guitar?

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I've got just about 1/2 of a quart left so it took about 1/2 quart minus the 1/2 cup or so I dumped out all over my bench The 3M disposable cups are pretty flexible

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Steve Smith
"Music is what feelings sound like"

Thanks Steve, good to know.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Not necessarily the way I'd do it next time but here is the schedule I used. I've posted most of this in pieces so I'm just kind of collecting it here:

1. 1 coat ZPoxy fill then sanded back to wood with P220. I hadn't used ZPoxy before and next time I'll probably do 2 applications; I had a few pores that didn't get filled.

2. 2 coats of 2# blonde shellac followed by a very light sanding with P600 then wiped with a damp cloth.

I sprayed with a Walcom EGO HVLP gun set at 2 bar (29 PSI), product feed at 2 1/2 to 3, other controls wide open (per manufacturer recommendations). Temp was between 65F and 70F, relative humidity between 40% and 45%.

3. 4 coats of unthinned PolyWhey at 2 coats per day about 2 hours apart. Lightly sanded with P600 after the second coat. Wiped with a cloth dampened with distilled water after sanding.

4. Level sanded with P600, wiped with damp cloth.

5. Sprayed one coat of unthinned PolyWhey and then contacted the manufacturer about maybe thinning the product as I was getting excessive orange peel. The next day I sprayed 2 coats of PolyWhey thinned 5 to 10% distilled water. The thinned product sprayed much better through my rig as I got a much smoother finish. I did some drop fills in a few areas.

6. After drying for 6 days I final sanded with P1000, P1500, and P2000. Final sanding was wet with mineral spirits. Finally I polished with Novus #2 and buffed with an ROS buffer pad.

Check my OLF Challenge thread for more photos and, in a few days, some photos of the finished guitar.

So far I like this product and I will use it again. Of course only time will tell if it will be a long-lasting finish. Next time I'll thin about 5% or 10% with the distilled water to start and probably spray 6 coats, level sand, then spray 3 final coats. I'll probably do 3 coats per day about 1 1/2 hours apart since it dries faster when it is thinned.

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Steve Smith
"Music is what feelings sound like"

What size tip are you using on your spray unit Steve. 1.5mm?

1.2mm

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Steve Smith
"Music is what feelings sound like"

Steve is providing much more information than can I at the moment since I'm just brushing on to a single board. Never-the-less here's what I got:

This morning, after allowing more than two weeks of curing, I sanded out my test piece going from 320 grit up to 2000 grit. Then I buffed it out only using the fine "white diamond" bar from Lee Valley. Finally I hand buffed it with Novus 2 compound mostly to get rid of the specs left by the previous buffing. The following pictures show the results in various lighting situations:










I think it buffed out nicely and it still does feel harder to me than water based finishes I have used in the past. It has also been very easy. So I am thus far impressed. The next phase of this test is to let it sit for another couple of weeks to see if I see any sign of further shrinking. Then I will attack it physically and chemically to see how durable it is. I am becoming optimistic that the stuff is worth testing on a guitar. I'll keep you posted, and thanks Steve, for showing your results. Your guitar looks good.

Cheers,
Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Pat, that's good info and I'm thinking the more folks that try this the better. I agree with you that it is easier (than EM6000 in my case) and buffs out nicely.

I'm hoping someone will spray something real dark as a test. I might do it after I get this guitar done.

Some more observations:

1. Recall I waited 1 week to buff (gotta get it done for the Challenge), I'm seeing some more shrinking on the top - getting a tiny bit of corrugation. Ideally I think it would be good to wait at least 2 weeks like Pat did or even 3 or 4.

2. Finish will bubble up if you apply too much heat (just like other finishes so not a big surprise). I did this when heating the area before re-gluing the bridge. Fortunately you can sand it back, repolish, and recover somewhat. It can be seen but not unless you look close. I will probably try to touch it up later just to see if that's something we can do with this product. This isn't the first time I've done that on a repair - I think it's time to move the heat gun to the other shop and get a hair dryer down here.

3. On the BRW headplate I'm seeing a very slight bluish tinge - this is under fluorescent T12's and high temp fluorescent task lights in the shop. Outside under a gray sky it looks fine. Haven't had any sun yet so don't know how it looks there. I don't see this bluish tinge anywhere else.

4. Finish will crack if it is stressed too much. I pressed in a tuner ferrule and hole was undersized which caused a couple of 1/8" or so cracks in the finish in line with the grain on the headplate.

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Steve Smith
"Music is what feelings sound like"

this isn't the first time I've done that on a repair - I think it's time to move the heat gun to the other shop and get a hair dryer down here.

Warm the bridge, and not the top, and apply the glue to the bridge-only. Also, it need not be hot, just warm. Hide glue gels at about the same temperature as your body temperature, so if a piece feels even slightly warm to your touch, you know it is well above the gel point. Yet another reason not to over-heat wood before gluing is that if you get it too hot, you're pulling oils and resins to the surface, which will hinder, not help, the bond.

Finish will crack if it is stressed too much.

That's not good news, especially for such a freshly applied finish.... Someone doing the panel tests should also test this finish's ability to expand and contract with the wood by freezing the panel at least 12 hours, then quickly allowing the panel to return to room temperature. And repeat the test at least a few times, especially a few months after the finish was applied to the panel, because most finishes are flexible enough when fresh, yet become too brittle when fully cured. And do test it on a thin panel as we'd use on an instrument.

As always, instruments endure conditions and treatment that is very different than furniture or yachts or floors. Instruments are made with thin, delicate woods, and must travel, which often involves rapid changes in temperatures.

There's much more to think about when considering a new finish than its ability to look good and survive the player's body chemistry....

I'll try the freeze/thaw test at some point.

Steve, once when I was pushing in some tuner ferrules into a guitar head with a BRW veneer, I cracked the actual veneer along the grain. Lesson learned about making things overly snug. Have you looked close to confirm that it wasn't just the finish that cracked?

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Mario, that's good to know about the bridge - I'll do it that way next time. I'm in the habit of putting glue on both surfaces when I can (although not usually with HHG), it helps me to control squeeze out better while still being confident that I don't starve the joint. First time I glued on the bridge I put the glue on the cold body only; I won't make that mistake again, part of the glue gelled before I got the bridge down which resulted in very poor coverage and a failed joint. There's a photo in my Challenge thread.

Pat, I'll have to check it under magnification - it's quite possible. Obviously I've been moving pretty fast to meet the Challenge deadline and have not been as careful as I usually am.

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Steve Smith
"Music is what feelings sound like"

I'm glad some of yas have tryed it .
I will use it from on every guitar from now on!

I will still seal with shellac first.
Guitar parts(backs/tops/sides)are to thin to apply any
water base finish to.

They have a wipe-on Polywhey finish that I just
tried on every wood in the shop.
Plus I applied it over Shellac .

It's self leveling!
(It drys level)
Looks great !
And drys hard .

Gee -it doesn't get any better then this.
Plus it low V.O.C.

Enjoy!
Mike

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Mike Collins

Mike, does the whipe-on product come in gloss?

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

YES!

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Mike Collins

I have almost completed my second guitar and I decided to give the polywhey a shot. I used em6000 on my first earlier this year. I have the same Walcom gun Steve has so I pretty much followed his finishing schedule with a few exceptions. I used system 3 epoxy porefill and left a thin layer on rather than sanding back all the way to the wood. I had a bad experience trying to do that on my first guitar. I did not use any shellac, I just sprayed the poly over the epoxy. I am not very good with spraying yet (I'm slowly getting the hang of it) so keep that in mind as you read this. Thus far, I can agree that this stuff is easy to work with. The hardest part for me was getting my gun dialed in correctly. I did end up thinning every coat about 10% and I put about 10 coats on. The first two of those ended up being very dry due to me not knowing what I am doing. I also agree that it is very forgiving. I had two instances where I sprayed a bit too heavy and thought I was going to be sanding out runs but it leveled itself out very nicely.

My only issue now is that I level sanded after 6 coats and forgot to thin my 7th coat so I ended up with more orange peel than I should have at this point. I may spray an extra coat or two in case I have to do some extra leveling in the end. I plan to let it cure for at least 2 weeks and then I'll post an update.

If any of you that have tried it have also tried KTM-SV, how would you compare the two? I've used KTM-SV so that is my reference point. One nice feature about KTM-SV is that you can go spray to buff in 1 week if desired. One thing that seems to be appealing about this product (from the responses here) is that because it dries slower, burn in may be better that KTM-SV (at least for finishing after building.....possibly not for later repairs).

Does this finish have any problems drying/curing on oily tropical woods? Tha tis one achilles heel of KTM-SV. The fix is to seal the wood well before spraying but it can get you in trouble if the seal isn't perfect (miss a spot with the sealer).

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Formerly known as Adaboy.......

I ordered a quart & it arrived today.

Would you spray it in your basement?

I've got a mask to protect myself, but what about the "stink factor".

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Kevin,

I spray in my basement also. My wife has a nose like a bloodhound and can normally tell if I open up a can of kerosene down there but she hasn't said a word about this stuff. I would say any odor completely gone 10 minutes after spraying in my experience.

Jeff

Mike,
What do you pore fill with?
Thanks,
Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

They sent me some of the wipe on PolyWhey to try too. Glad to hear you like it, I'll give it a shot. I've got a small area on the challenge guitar that needs to be repaired so this will be a good opportunity to see how it works.

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Steve Smith
"Music is what feelings sound like"

Pat I'm going to use this product now.
Even if I have to take more time and need to add more coats.
I've been using the stew-mac clear sealer.

I like no color added to my woods-just a enhancement of
the natural wood grain.
Hence the clear filler.
I will still seal with Blond shellac.
http://www.shellac.net

Mike

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Mike Collins