Official Luthiers Forum!

Hi everyone, I'm new to the forum and this is my first post. I have used Aquacoat pore filler and also BSI epoxy to fill pores on mahogany and walnut. I gave up on the Aquacoat, as it shrinks back too much and requires several applications. The epoxy is messy but works far better and normally only takes a couple of coats.
I would like to darken the mahogany with the Stewmac water based dyes, but also pore fill. I have done this on a mandolin using the Aquacoat pore filler and said dyes. The result was ok but not ideal, so would like to use the epoxy and same dyes. I'm afraid that if I dye first and then epoxy on top, that I would end up sanding through leaving a patchy finish. I realise I may have to practise the technique on some scrap, as I have seen a member of the Mandolincafe forum do this successfully after a lot of experimentation.
I'm not ruling out using the Aquacoat, but wonder what the best way of doing it in the hope of achieving a better result than last time.
If anyone has any tips or advice, I would be most grateful.
Many thanks Mike

You can add dye to the epoxy.
I have found that wiping the epoxy with a paper towel can produce a pretty smooth surface that requires minimal sanding.
I had the same poor results with aqua coat.

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wah
Wah-wah-wah-wah
Wah

Thanks Dan, I shall experiment with that.

I have tried many filling methods and nothing works better than old fashioned, oil-based, paste wood pore filler that is tinted to a dark chocolate brown. Apply to mahogany that has been sealed with a coat of thinned lacquer. It brings out the beauty of mahogany grain like nothing else.

aqua coat
always worked well for me.. You did seal first didn't you ? I use 2 applications as it dries in 30 min.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I love Aquacoat. Are you saying that it shrinks back after many years or between coats? 2-3 Aguacoats typically is good enough for me on porous woods.

I've tried most and now use Aquacoat. The Aquacoat tints well with StewMac ColorTone liquid stain.

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Steve Smith
"Music is what feelings sound like"

I've stained mahogany only once, but the method I used was similar to what you are thinking of doing and it worked so I'll describe what I did.

The person I built the guitar for wanted the color of the mahogany neck to match the color of the Indian rosewood body. I applied the dye (Behlen Solar-Lux) to the neck by wiping it on. I used z-poxy on top of that as pore filler and, like you, I was concerned about sanding through the z-poxy and getting blotchy color. I dealt with that by applying 4 coats of z-poxy instead of the usual 2 or 3 coats and, instead of level sanding each z-poxy coat to about 90% completion, I level sanded the first three coats to only about 40% and then fully level sanded after the fourth z-poxy coat was on. I applied the z-poxy by wiping it on with a gloved fingertip. No sand through except for a tiny spot along an edge of the headstock. I was able to fix that by applying stain to the spot with a Q tip. If I was going to do it again, I would do it the same way except that I use System Three Silver Tip epoxy now.

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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

I stain mahogany all the time to match other woods, usually rosewood. I apply a stain made from transtint dye (Colortone) dissolved in DNA to get the color I want. Then I pore fill with Zpoxy, usually two or three applications. The first is full strength, I sand it back level with the wood surface being careful not to remove wood. The stain isn't affected because it has absorbed into the wood. I'll do one or two further application of Zpoxy highly diluted with DNA - that soaks into the wood a bit and really pops the grain. Seal and lacquer over that.

This is Madagascar rosewood





This is cocobolo (a bit redder than the Mad rose)





I've done the same with brown and it came out OK. As with any finish question experiment on scrapes of the same wood.

I've also used tinted paste pore fillers - StewMac used to sell it in several colors.

Thanks everyone for your replies. I'm encouraged by the methods shared regarding the epoxy use, but I also note your comments about the Aquacoat. I shall experiment with both before I decide which way to go on an actual instrument.
DNA is not something we have here in the UK, but I'm led to believe our Methylated Spirits is a good substitute. Please correct me if I'm wrong.
Cheers Mike

I use Isopropyl alcohol in preference to Methylated Spirits (mixed with methanol, emetics and other adulterants) because it is easily obtained in 99.9% pure form (<£20/5liters on Ebay) and it's vapour is less toxic, and less unpleasant to work with.
Main uses for me are for shellac (grind in coffee grinder first) and diluting epoxy for wash coats. And for hand sanitizer...

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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.

Mike, industrial denatured alcohol (IDA) is available in the UK but you usually need a government permit to purchase it. This is easily available and cost free from HMRC.

https://www.bonnymans.co.uk/product-pag ... hol%20(IDA)%20also,which%20leaves%20no%20residue%20behind.

If I remember correctly I completed the form online, I use it for french polishing and gave that as the reason for my application.