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I just built a jig to hold my guitar body in order to spin it as I foam brush the top, back, and sides at the same time. Been a long time since I finished a guitar and applied a light coat of EnduroVar, went back to check and the sides ran immediately and I can see some fun sanding coming up. Thought I put on a light coat but it ran anyway.

Will probably figure out a system that works but what do you all do to keep some of the 4 sides from running? Spin it around? Wait for it to set up while spinning?

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At some point Bruce Petros was putting his guitars on a barbecue spit. Don't know if he still does.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Which direction does your jig hold the body, vertically or horizontally?

Do you you thin your EnduroVar with water or extender for brushing it on?

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Horizontal and I apply the Enduro straight from the can...

I'll re-apply today and turn a bit while it sets up. Top alone and back alone is no problem but each side has a vertical surface of some kind...

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According to GAL (118, p18), Greven is applying under a heat lamp.

VERY interesting... also see mention of a heated room in this video www.youtube.com/watch?time_continue=2&v=FXr9jYoikcA

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Jay is using EM6000 which stays put. It's the easiest to apply for sure! I just picked up a quart of enduro-var to see if I can make it fly. I'd sure like to lose the blue-cast.

Knew he was using EM6000 - did not know it 'stays put'.

I'm trying a little different tactic by coating the top and back at the same time, spinning and keeping horizontal. Will next coat the sides and see if I get enough on to build and keep it from running by watching carefully and spinning as needed. BTW not hard to heat my shop to 75-80 here in SoCal. See if that makes any difference.

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Thank You and Best To All

FWIW, KTM-SV lays down with no blue cast. No idea how it compares in any way to em6000 or endurovar in other aspects as I gave up on WB a long time ago...

It does stay put. In fact, straight EM6000 sets up too fast for brushing so you have to add their retarder to keep it liquid long enough to brush on. With the right amount of retarder, the "open time" can be lengthened just enough that brushing it on is doable while keeping the viscosity high enough that it doesn't run. I do thin coats which helps prevent runs. I also use a bristle brush which I found gives me more control over the application than I was able to get using foam brushes.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

THANKS

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Thank You and Best To All

I spray Endure Var exclusively (at the moment), with the holder horizontal.
Spray one side, rotate and then the other side, then rotate several times until it looks to be settling down.
After the coating on the sides self levels and starts to look "stable" , then I go on to do the back, rotate, then the top, and continue rotations periodically.
I then watch it, rotating it occasionally if required until it has "flashed off" after which it can be hung up.
Only problems with runs/sags is if I lay it on much too heavy.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Thanks Colin,

I have a spray rig but no real booth nor the patience to spray, clean, spray, clean, spray, clean, for the 15 (or more) times needed to finish a guitar. May revert to using the sprayer if the brush method fails but it's so easy to sand back level and clean up a single foam brush at a time. Maybe I'll try your schedule, sides first, with the foam brush.

Do you have a heated space for spraying?

This may sound a bit silly but I have my heat gun set up in a holder (as well as a dedicated small heater) that blows across the room and heats my small space really fast. Just tried brushing at about 80 F and everything flashed off quickly with no runs but didn't lay down at all. No real surprise, but maybe there's a middle ground...? Or maybe a small spray both is in my future.

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Thank You and Best To All

Yes, heated shop, like it about 70-75. 6 coat schedule for EV gloss enough if spraying, don't know about brushing. Short time between coats can mean gun doesn't need cleaning every time.
Only need to run water though the gun to clean it anyway.
Full clean up only after guitar finished.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

VERY helpful Colin appreciate your time to reply.

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Thank You and Best To All

OK, here's something a bit different. Tried coating the sides first and while brushing WB the usual M.O. is to brush then stop as soon as you get an even coat so the WB can level. In this case I just kept brushing (1 1/2" foam brush) the single side and as you can guess the brush started to drag a bit, which leads one to believe the EV has flashed off enough to not run. The common wisdom at this point is to stop brushing or may even be that it's too late already but instead I kept brushing.

The brush was dragging pretty well at this point but the brush marks were very small (foam brushed sized) and the coat was certainly not going to run so I went on to the other side. Started with medium full brush and just kept on brushing. A couple times with just the right touch and timing it was getting somewhat burnished like a french polish. Brushed until very dry brush and dragging with a very light touch.

Back to the other side etc. Spent 1/2 an hour coating and re-coating one side then the other using this dry brush technique. Maybe 10 coats? Not sure how well it built but there's only very shallow brush marks that should sand very easily. Could be as serious flaw in this technique as time will tell but it did allow for multiple coats in a single session.

There does come a time using this method when you know you are done as the build can be seen and one is essentially putting on a pretty thick single coat with the inherent downsides but I'll sand later today and check conditions.

Shop 76 F and 40 RH.

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Do you have any idea how many wet mills you are shooting per coat?

Thanks, M

I tried measuring wet coat thickness with a gauge, but have not been very successful, so far.
From the final thickness on the soundboard (which is 2.5-3 thou, at 28% solids) wet coats are around 2.5-3 thou each coat.

First 3, gloss base coats, are all sanded back P320 after spraying, I measure ~1-1.5 thou mid way.
Then I've been shooting 2 coats of satin on top, giving 2.5-3 thou total thickness.
If I want gloss, I shoot 3 gloss top coats and then dry a week, sand flat, and buff.
(sorry, thou = mils, - mils confuses me because I think millimetres)

Jeff Jewitt's recommended (via GF) schedule I posted (just after you did) in this thread here -
http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=51192&p=673989&hilit=+schedule#p673989

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Just a quick follow up in case there's any interest. The above method seemed to work but is essentially a long process that puts on a single, thick layer of finish with its inherent weaknesses, mainly long dry time, but other than that it might save some time.

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Thank You and Best To All