Grain filling problem

[DMP]

I’m trying to finish my rosewood tenor with shellac, but first I need to fill the grain. Problem is, I can’t remove the sawdust that’s filled the grain after sanding. It’s lighter in color than the rosewood itself and doesn’t look good. I plan to use Aqua Coat, but before I apply that, how do I get that sawdust out of the wood grain? Thanks for any suggestions. I’ve never used rosewood before, so this is a new problem for me.

 

[sequoia]

What I do: Take a strong shop vac and really suck that stuff out. Carefully so as to not scratch or mar the wood. Then I wipe down with spirits (I use denatured ethanol but many use naphtha if you can get it which I can't because I live in California). This also takes some of that rosewood sap out which can color your filling compound.

 

[BR Ukuleles]

Vacuum or compressed air.

If you use any type of solvent like alcohol or accetone you have to be extremely careful as Rosewood color will bleed like you will not believe into anything lighter coloured, like purfligs, bindings, spruce. You've been warned.

I would try your Aqua Coat on a scrap bit with some some of the same saw dust in the pores that you have on the body. It may wet that out and become far darker than when it's dry. This will happen if you use CA as a pore filler, as well as some other fillers.

 

[sequoia]

Rosewood color will bleed like you will not believe into anything lighter coloured, like purfligs, bindings, spruce. You've been warned.

Yup, yup and yup... I once got some rosewood color on a maple neck. I ended up "staining" the entire neck with rosewood bleed to cover the spot. Actually turned out rather attractive. Making lemonade if you end up with lemons. But DO NOT get any on a spruce top or you will be in deep do do... Another thing I neglected to mention is that using a solvent on wood (even rosewood) may tend to raise the grain if you haven't done a "raise the grain" sanding step. If it does happen, lightly sand again with fine (~320) paper and repeat solvent wash until you get smooth. Usually 2 or 3 times depending on wood.

 

[Moore Bettah Ukuleles]

The sawdust in the pores will likely turn as dark as the surrounding wood once you use any grain filler, sealer or finish.

 

[Brett S.]

use a brush attachment on your vac

 

[Beau Hannam Ukuleles]

A better solution is to:
1- Hand sand the back with 220 or 320.
2- Leave the dust in the pores and,
3- Flood it all with thin ca glue.

At this stage, you can either sand the ca flat and pore fill, or sand it back to wood and pore fill.
Either way, you will need to wipe with naptha to remove all the white ca dust before pore filling and finishing.

This will do three things-
1- Deal with (fix) any invisible micro cracks.
2- Seal the wood.
3- Partially fill the pores.

After this you can proceed with whatever pore filler then finish you are using.

After the back has been ca'ed, do the same with the sides.

ps- this is a good and safe way to go about all things rosewood if you are selling an instrument professionally- if you are making it for yourself....it might be a bit of overkill.

 

[DMP]

Some great ideas here. Thanks. One question: I’m in California, so naphtha is out. What’s a good alternative?

 

[dsorlien]

Some great ideas here. Thanks. One question: I’m in California, so naphtha is out. What’s a good alternative?

I think we can still get Klean Strip VM&P Naptha from Amazon shipped here. I bought some about 2 months ago and it arrived quickly.

 

[Beau Hannam Ukuleles]

Some great ideas here. Thanks. One question: I’m in California, so naphtha is out. What’s a good alternative?

Denatured alcohol

 

[tonyturley]

A better solution is to:
1- Hand sand the back with 220 or 320.
2- Leave the dust in the pores and,
3- Flood it all with thin ca glue.

At this stage, you can either sand the ca flat and pore fill, or sand it back to wood and pore fill.
Either way, you will need to wipe with naptha to remove all the white ca dust before pore filling and finishing.

This will do three things-
1- Deal with (fix) any invisible micro cracks.
2- Seal the wood.
3- Partially fill the pores.

After this you can proceed with whatever pore filler then finish you are using.

After the back has been ca'ed, do the same with the sides.

ps- this is a good and safe way to go about all things rosewood if you are selling an instrument professionally- if you are making it for yourself....it might be a bit of overkill.

Beau, I watched your video on pore filling with CA. What were you using to spread the CA? Sort of looked like a cotton swab to me. At some point later this year, I'll be pore filling Red Oak back & sides. I don't plan on completely leveling the pores, but I do want to have some level of filling, as Red Oak is so open.

 

[Beau Hannam Ukuleles]

Beau, I watched your video on pore filling with CA. What were you using to spread the CA? Sort of looked like a cotton swab to me. At some point later this year, I'll be pore filling Red Oak back & sides. I don't plan on completely leveling the pores, but I do want to have some level of filling, as Red Oak is so open.

HI,
The cotton swab looking stuff was actually Bounty kitchen towel - some towel kicks off the ca glue way quicker (don't use viva)- bounty seems good.

I no longer grain fill with CA glue as the fumes are just too much and linger for hours in the workshop- I do still use CA to stabilize problematic woods like Brazilian rosewood.- I flood the wood with thin ca which deals with any invisible micro cracks- but this isn't a pore fill.

If I want a clear pore fill, I use either West Systems epoxy or Zpoxy PT40- It's self leveling finishing epoxy (LMI also sell it). Pore filling prep is a 2 or 3 day process- don't rush it if you want a flat finish.

https://www.amazon.com/gp/product/B0006O8ESK/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

 

[Jardin]

I just thought I would put it out there that you can just use Everclear or grain alcohol instead of all the chemicals....I worked at a printing press as a young artist and because of the over-exposure to acetone and such I became chemically sensitive and therefore make my instruments with little to no chemicals and Grain Alcohol works great.....What cracks me up is it is not legal in some places yet the nasty stuff is....

P.S. after re-reading this it sounds a little judgemental and that is not my intention.... You do you as they say nowadays. I just try to be ecologically minded and health conscious as it can be very hard to live in this world full of chemicals when you get migraines from all of it....So for those who want the option, here is one solution.

 

[sequoia]

Like Beau (Beau knows) I just use denatured ethanol (camp stove fuel ethanol 99% pure). Stinks but non-toxic vapor. Toxic to drink obviously. Cheap.

Certainly Everclear is the go-to solvent for lots of luthiers. Plus when things go wrong (what could go wrong?) you can add it to your lemonade and drink it. However I have two problems with Everclear:

1) It's very expensive
2) It contains 10% water

 

[Beau Hannam Ukuleles]

Of course, you can also just use water t wipe away ca dust- it just takes longer to evaporate....especially on raw wood. I won't use water on raw wood unless you are raising the grain on purpose.

 

[tonyturley]

Thanks for the info and the link, Beau.