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I've only done tru oil open pore on mahogany/ spruce or on maple/spruce over a sprayed shellac burst. Always pleased with the result. Have my first rosewood getting towards finishing, red spruce over dalbergia spruceana with cherry binding. Neck is I can't remember which mahogany substitute which I'm going to stain darker and do an open pore finish. Does rosewood look as good as mahogany with an open pore finish? If pore filling is recommended do you recommend using the oil and sanding method?

Thanks all.

Pics hopefully

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Oil based finishes on oily wood like rosewood can be a real hassle.

The oils in the wood often prevent the finish from drying. It can stay gummy for weeks, maybe forever.

Undercoating with shellac provides a barrier and will allow the TruOil to dry properly.

I'd suggest brushing a couple coats of dewaxed shellac and sanding it back to a relatively smooth surface and then wipe on a thin coat of shellac to seal any wood exposed thru sanding. Then hit that coat lightly with 400 grit and start your tru oil.

Be careful not to sand thru the shellac on corners or the drying issues may show up there.

Make up a couple test tiles with your RW and try your intended finish schedule to make sure everything works.

If you do end up with a spot that doesn't want to dry, I've had luck wiping off the sticky with naphtha or mineral spirits, spot coat with shellac and resume with TOil.

TruOil is one of my favorite finishes.

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Brian R, Wood Mechanic
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Thanks Brian, that sounds great. Any idea how much shellac roughly I should mix and what ratio? Just to be clear, your technique will give me semi filled, sealed pores?

Mike

The barrier coat of shellac doesn't need to be thick as much as continuous. I usually use a 2 pound cut because I want it to do some pore filling. But you can use a 1 pound cut and it will be fine. I think maybe 4 ounces should be plenty to seal a guitar body and have a little left for touch-ups.

Just make sure it is dewaxed shellac.

If you are using light colored bindings or anything you probably want to wipe a thin coat of shellac over the lighter woods as the alcohol can pick up color from the RW and stain the light wood. As your pad picks up color just use a fresh spot, even a paper towel will work for that. Following coats done lightly at the intersection of RW and bindings should not pick up more color.

Any finish will do some pore filling but they will still show - harder to get rid of pores than keep them.

Do a little practice on a RW cutoff and you'll find what works quickly.

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Brian R, Wood Mechanic
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Ok brilliant, it's coming together in my head...

I'm thinking about the top edge of my cherry binding, if you see the pic there's no purfling between the cherry and spruce, would you put a coat of shellac over the spruce top as well?

I always run a thin coat of shellac around the top to protect it from tape or glue and in the rossette. It gets sanded back in the process of finishing the top anyway. But if it still shows I pad on a thin coat of shellac to even it out regardless of the top coat.

With TruOil I do pad on a couple thin coats of shellac to the top and scuff sand it before TruOil. I just don't want the TruOil soaking into the top. But in reality, TruOil dries so fast it really doesn't soak in like other "oil" finishes. A nice thin even coat of shellac on the top will ensure a nice topcoat.

Understand, finishing is probably my biggest struggle and I'm not a pro, but this is what works for me.

Good luck

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Brian R, Wood Mechanic
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That back is going to look really pretty when you get some finish on it!
I have done Tru Oil and also Hard Wax oils over rosewood. I think Brian's advice is spot on and I can't think of much more to add. I also did partial pore filling by wet-sanding with shellac. That RW dust slurry will really colour your bindings and any of the soundboard that it gets in contact with, so it is a great idea to have them sealed with some shellac before you start on the back. Then sand the RW stains off the bindings and soundboard, and reapply fresh clean shellac before you start with the oil. This is one of the most satisfying parts of the whole build.

Ok thanks people, I brushed on a couple of coats with a foam brush, I'm even worse I think with a bristle brush. I'm sanding back, then I need to 'pad on a single thin coat' is that right? Please explain or direct me to what and how exactly I'm doing when padding? Is this the same as FP padding with oil and everything?

Mike, by "padding", all I mean is using a pad of some fabric folded into a "pad". I like an old linen shirt, some like t-shirt material, or even a quality paper towel. I fold the pad so the raw edges are inside to reduce lint. It is similar to french polish but only in the pad applicator. No need to add oil to the pad or to spirit off oil with alcohol or anything like that. Some folks like to thin the T-Oil with naphtha or mineral spirits for the final coats.

Make your pad and then load the pad with some T-oil and wipe it on. It takes some practice to know how fast to move and how much or little to overlap. If it gets sticky you are moving too slow.

You can lay down a couple thicker coats and then go with thinner coats. Quit when you like it. I've used anything from 3-4 coats to 20-30 before I was happy with the look.

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Brian R, Wood Mechanic
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Eugh, thanks sorry, I was asking about padding the shellac undercoat but I was totally unclear. I brushed two SHELLAC coats and sanded them back to wood leaving shellac only in the pored. Now I need a shellac undercoat as I understand it, before tru oil.

Yes, doesn't have to be a thick coat but complete. 2 thin coats might ensure complete coverage. But no oil as in FP. Just wipe on a couple thin coats of 1 pound cut or there about.

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Brian R, Wood Mechanic
N8ZED