Alternate Pore Filler?
 

Besides making guitars, I build skin on frame boats at the Canadian Canoe Museum in Peterborough On Ca where I live.
The nylon or Dacron skin is sealed/waterproofed with a unique 2 part, non toxic, odourless catalysed polyurethane. It stays flexible and doesn't seem to shrink .
I pore filled a piece of Cocobolo, sanded back to the wood the next day, and applied a coat of true oil that day after. Pores are totally filled .
It sands more easily than epoxy, and not as toxic.
Skinboats.org $15us for 12 oz.
Think I will give it a bigger test on white ash.

Interesting!
 

My wife has old friends in Connecticut who built Woden canoes. Man they were beautiful!
I have read of an old technique using egg white pore filler, but I doubt it would like getting wet...

Carry on and remain musical!

Paul

Thanks for sharing the tip Russ. I wonder how it will hold up to the heat of a buffing wheel. That is where I’ve seen some porefillers and incompletely cured finishes shrink back or shortly thereafter in the next few days.

Thanks for the tip.

Is this what you're referring to?

https://shop.skinboats.com/Urethane-...er-goop1-2.htm

Yup. That's the stuff

I visited that museum a few years back! My brother used to live in Peterborough and I was there for his wedding and stopped in. Cool place! One of those places that you think "well how good can a canoe museum be?" and then are amazed!

I recently saw a guitar with the grain filled with gold powder. Looked interesting

JR

Most interesting.

I wonder if high flexibility might indicate high damping?

Yes, the Canadian Canoe Museum is amazing. New visitors are always saying that.
Gold powder pore filler, sounds really interesting. Love to see that.
I don't think the elasticity would cause any dampening since it only fills the pores and doesn't penetrate the wood like oil. But I have been wrong before, or so I've been told. Lol

I buffed the Cocobolo test piece on a high speed buffer with a rag wheel, and there was ne effect, pores remained totally filled.
I did a test on a larger piece of white ash, and it worker just as well.
The one difference in working it, is that because it remains slightly flexible, it doesn't scrape well, but sands more easily than epoxy.
My main reason for this experiment is my dislike of working with epoxy. The smell, off gassing and dust. There are a lot of things in guitar making that are unhealthy, that we all deal with as best we can. If I can remove one from the mix, I am happy.
I feel confident enough to try it on my next build. Russ Parker

Curious, does it wet out and pop the grain as nicely as most epoxies?

it is always interesting to hear about expansion of the arsenal of finishing tricks. Thank you. I never seem to hear about it, but it is entirely possible the do a very nice guitar finish without using pore filler at all. both of the single 0 guitars I am bringing to B.I.G, (B'sox International Guitarapalooza)for instance, have no pore filler. One is from Pernambuco which had nowhere to put the pore filler, but the other is Honduran Mahogany, which has notable pores. It took 2 more coats of finish to get the Mahogany guitar dead flat. Having no pore filler (or clear pore filler but I am anti-epoxy in a wood guitar) looks VERY beautiful to me.

Yes, it wets out the grain well, possibly not quite as well as epoxy, but then they are both sanded off back to the wood.

I have offered wondered about just levelling with finish alone, but didn't know how many more coats I would need. That is great info.

When And if I do pore fill with this polyurethane I will certainly post the process and results.

The company that sells it is a one man operation, and all his products are bio safe. Www.skinboats.org. While his business is a skin on frame Boat building school and store catering to the skin Boat community, I think this might work for guitar finishing. I certainly wouldn't use it for a final finish, as it is thick and would kill the sound, but pore filling, maybe!

Here’s a note on egg white as pore filler: https://homegrownlutherie.wordpress....th-egg-whites/

Russ,
Thanks for sharing but don't rush to judgement quite yet. Heat induced buffer shrinkage of the finish back into the wood pores will not likely show up until sometime in a 1-4 week window.

I also just noticed that this is a polyurethane product. Another test you might want to perform is a bump test, with the sharp corner of a hammer head. You have to hit the wood hard enough to dent it slightly. Polyurethane products, typically have poor adhesion properties, especially if the surface is subjected to an abrupt bump against a sharp object. Many poly products will de-laminate from the substrate or base material and will show up as a white or cloudy circle in the finish. You can often read "cross hatch" test data if the OEM performed that adhesion test? This is a different test than a bump test but it is another metric to which many finish products are measured. The bump test simulates what a guitarist might encounter, if they bumped their guitar against a sharp corner, like a corner of a coffee table. When the finish de-laminates its an easy repair with CA but its a tell tale sign to the repair person that the finish has poor adhesion properties.