Proper preparation for finishing

ChuckBarnett

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Happy to show pics of the last hurdle -binding top and back!

I've heard that sanding is not best as you have wood pores clogged with sawdust. Better to use a scraper. But then I read that softwoods don't do well being scraped.

Greenhorn...
 

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No problem sanding, in fact pore filling can be achieved by wet sanding with finishes, so it's not necessarily a bad thing. It's true that scraping can give a finer smooth finish, but it's not necessary.
 
Violin makers use a scraped finish and some construct 'sandpaper' from a plant to prep the surface. Scraping to a finish? Never done it and know only a few who have looked at this as an experimental exercise. Sand to 220/240 for sprayed finishes, finer for 'Tru-oil' style finishes. Try shellac at your peril. You will fuss and fuss with this deceptively 'easy' finish that is anything but, despite what you might read here and in other places.
 
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Violin makers use a scraped finish and some construct 'sandpaper' from a plant to prep the surface. Scraping to a finish? Never done it and know only a fe who have looked at this as an experimental exercise. Sand to 220/240 for sprayed finishes, finer for 'Try-oil' style finishes.

Yeah, Pete, that leads into the whole question of what I will do about finish. The very little I've done tells me that I'd be wise to hire that done. Spraying takes experience plus... I'm considering French polishing at this point. Would 240 do fo that?
 
Yeah, Pete, that leads into the whole question of what I will do about finish. The very little I've done tells me that I'd be wise to hire that done. Spraying takes experience plus... I'm considering French polishing at this point. Would 240 do fo that?

Remember, you don't have to pore fill. I do a pore fill, but it isn't written in stone that all those pores have to be filled... I sand out to 320 and use a shellac finish wet sanding after each 3 coats. You also don't have to get all obsessive and "French polish" to get a nice finish. Put it on thin and expect +12 coats to get there. Safe, non-toxic and actually kind of fun.
 
From what little I've learned, pore filling is important for high gloss finishes. I don't know anything about finishing beyond polyurethane. I did roller paint my powermatic 65 with an oil whatever it was (enamel? lacquer??). Turned out pretty decent, especially beneath a fine patina of sawdust! Pore filling supports the finish for a better look. What does it do for French polishing?
 
you dont grain fill soft wood tops
 
And I have a couple of those around the binding. Rosette is clean. That's a good tip, Chuck. What do you use for filler? I apologize once again, this is all new stuff to me.

For me, it is almost inevitable that there will be a small gap somewhere along the binding. Almost always along the sides. I tape off the area very carefully and then fill the tiny gap with a white glue-sawdust mixture. I usually have to do that 2 or 3 times because the glue shrinks back. Remove tape, sand out when dry (overnight) and any gap is virtually invisible to the eye. Only I will ever know. I know where the bodies are buried and I'm not talkin'.
 
And I have a couple of those around the binding. Rosette is clean. That's a good tip, Chuck. What do you use for filler? I apologize once again, this is all new stuff to me.

I'm talking about the ones you can't even see they are so tiny. You may not even see them while you're spraying lacquer. They'll often show up after the lacquer has cured for a while or you discover them while buffing. (We're talking abut trying to achieve a perfect finish-others might not care much about the errant pin hole.) I use medium ca glue as a pore filler and running a swipe around the bindings and rosette will take care of any minute gaps.
 
Great advice Chuck. Those gaps 'grinning' at you half way through buffing are REALLY annoying!
 
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I'll reiterate.
I grain fill the rosette if i've used woods with deep grain.
I fill binding/purfling gaps etc.
I drop fill (with nitro) anything I missed.

But i don't grain fill the whole soft top
 
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