Thread: Silky Oak I'm not loving the pores I'll have to say.

Hopefully Neil will see this thread, he wrote the book on finishing.

Sorry should have added these earlier

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I would use pumice powder, here's a link to a video on the method How to fill the grain using pumice powder before French polish your guitar. - YouTube

Will that matter if I'm pumicing shellac rather than the wood layer as I'd have a time getting back to the wood level with the current finish I have on there?

You can start filling now (each new layer will still soften your previous build up of layers) and keep filling each layer until the grain is filled.

Originally Posted by InsertTabA

I'm wondering should I thicken the mix or should I be sanding back between? I've tried the fine sawdust and plaster of paris method on test pieces and didn't get what I was after.

Do Both .
Your building a body and trying to fill grain which is deeper pit holes . Thicker shellac is good for this .

After a session dries off cut it back, sand it . As hard as you can with oil and turps on a 320 paper without going through and touching wood .
Then start another body. Shellac with circles and figure eights . Add pumice if you want to . Ive never used pumice at wood level . Its an additive I use while between layers of shellac.

Three good body's with three good cut backs should see you getting to the stage of using thinner shellac to finish the shine .

Maybe a little late to the party, because this needs to go on before any finish, but Aqua Coat is a fabulous product. Used by many luthiers. Wipe on, sand off after (from memory) 30 mins, apply again if you really need it.

Thanks to all helping it's making me more confident with some of the decisions.

Just a question re the sanding with 320 oil and turps, should I clean down before the next coat or is the aim to get some of the slurry to do some of the pore fill?

Originally Posted by InsertTabA

Just a question re the sanding with 320 oil and turps, should I clean down before the next coat or is the aim to get some of the slurry to do some of the pore fill?

Yes, clean and dry it off. Your just building a body and cutting back each time and Linseed oil and mineral turps 30 to 70 or 20 to 80 is just for keeping sand paper free and cutting the dry shellac good . Its not good at all to leave any slowly drying between the coats .

You can cut back and fill with other things that fill grain with the slurry but its a little more involved. And it speeds things right up if done correctly .

After the first few coats of shellac. If you rub back and use water with a few drops of PVA glue added and you make sure the slurry is a touch darker than the wood grain colour by adding oxide colours . You dont wipe it all off but spread it evenly and let it dry. You have to turned it to mud basically. With a glue hardener. Then when its fully dry you cut that back straight with 320 and oil and turps. This mud is now particles of coloured shellac in the grain being held by the dry glue . But the dry glue is thin enough that when its re wet with shellac later the shellac soaks in and re sets it making it one with the rest. Its a balancing act of the right ingredients that makes it work . And it works well . I do this sort of thing from the dry wood up using a couple of differing methods and by the time Im nearing the final shine at the end the grain filling is sorted with not much extra hard work needed by bodying with thicker shellac.