VIDEO- Pore Filling Koa with Epoxy (Z-Poxy)

Beau Hannam Ukuleles

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Epoxy used in this is Z-Poxy PT-40 (a self leveling finishing epoxy).
I've heard from some luthiers they got shrink back of the Z-poxy pore filler after buffing, then those luthiers tried WEST systems and got no shrink back.

I've also heard from other luthiers that they got shrink back after using WEST system......

So, aim for minimal heat when buffing with any pore fill.

Also, I pretty sure the pin holes above the pores were caused by leaving the epoxy too thick on the first coat. It's caused by opposing surface tensions of the wood and epoxy on the first coat.


 
You do great videos!

I've found that if the epoxy is getting pinholes or bubbles trapped in it, passing a torch or heat gun over it quickly can help get the air out and level things off before the epoxy cures.
 
I have been having a hard time finding the lighter amber zpoxy. I don't like the darker amber. I have been using smiths finishing epoxy. It's ok but I do like the zpoxy better.
 
Beau, thanks for sharing our expertise with all of us. Questiion: What set up do you use to control humidity in your shop.
I have a mini split system that works well for dehumidifying when running but when it has reached temp and has cycled off the humitdity rises again usually to 60 pct.
The system gets it down to the low 50s when running.
I live in South Carolina where it is hot and sticky in the summer. Any ideas other than moving??
 
I use this (plus two other types- ill do a video on it- but this little thing gives out pure humidity (fog/steam). the others just blow air through a wet filter (which only works if the filter gets wet, which it cant if its really dry....so its a crap design
 
I don't like the amber caste of Z Poxy nor its stinky odor. I use Smith Industries 20min cure epoxy with silicone 'bubbles' as a thickened first coat (the silicone fills the pores and you get no bubbles) and then unadulterated mix for second application. With this method I have had now problems with air pushing the lacquer out of the pores. I also use a squeegee to get the mix into the pores and before it cures rub hard across the grain with a cotton/polyester rag. See what I am doing? Combining modern and traditional techniques... it's why I think that if you have a background in a variety of craft/handworking/engineering skills you have a bit of a head start in this game.

I spray lacquer directly onto it and have had no adhesion problems... the secret is not to sand out to a super fine grit. 220 is fine, 320 max - go beyond that and you will get adhesion problems.

OH and well done Beau for this excellent public service. I did it once - you do it better.
 
Subsribed. And thanks for adding this video here.It's interesting to note that different luthiers have had varying experiences with shrink back when using different epoxy systems. Some have reported shrink back with Z-Poxy pore filler but not with WEST Systems epoxy, while others have had the opposite experience. It's a reminder that achieving the best results often involves factors like minimizing heat during buffing and applying the epoxy in thin coats to prevent issues like pinholes above the pores.When it comes to the best adhesives, i mostlly go with this one https://www.aerospheres.com/products/adhesives/loctite-super-glue-precision-5-gram-tube/. Tried few different products and this one seems to be the best on the market.
 
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