Oil finish to top - with bridge on, or not?

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John higgon
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Oil finish to top - with bridge on, or not?

Post by John higgon » Sat Jul 22, 2017 10:42 am

I'm planning to apply a TruOil finish to my spruce top. When using shellac I apply sellotape to the bridge area, polish the bridge and top separately, then remove the sellotape and glue the bridge in place. That's my preferred approach to the planned oil finish, but I'm wondering whether the oil will penetrate underneath the sellotape and then cause problems with the gluing - it is oil, after all. Safer to glue the bridge on first, then finish the top and bridge together? Or can I use the sellotape method?

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Michael.N.
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Re: Oil finish to top - with bridge on, or not?

Post by Michael.N. » Sat Jul 22, 2017 10:55 am

You can try sealing the top with a few applications of very dilute clear shellac - 1/2 lb cut. Not French polished but padded on in straight lines, just enough to seal the top. If it raises the grain cut back with fine paper and do another thin coat. Then you can mask your bridge and apply the tru oil. If you wish to apply tru oil direct to the soundboard I doubt that it will creep much under the sellotape providing that it's rubbed firmly down with the thumb and you aren't flooding the tru oil on.
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John higgon
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Re: Oil finish to top - with bridge on, or not?

Post by John higgon » Sat Jul 22, 2017 11:08 am

Thanks, Michael. But sealing the top with shellac and then adding oil on top? Will that work...? Won't the shellac stop the oil getting into the wood? I don't know much about finishing, so please forgive me if this is a stupid question.

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Michael.N.
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Re: Oil finish to top - with bridge on, or not?

Post by Michael.N. » Sat Jul 22, 2017 11:15 am

Yes it will work, just keep the shellac thin and don't allow it to build too much. You want it to seal the wood, not to form a finish on top of it.
Try it on scrap wood first but I've used the method many times.
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John higgon
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Re: Oil finish to top - with bridge on, or not?

Post by John higgon » Sat Jul 22, 2017 1:57 pm

Lovely! Thanks for the tip, Michael. :bye:

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James Lister
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Re: Oil finish to top - with bridge on, or not?

Post by James Lister » Sat Jul 22, 2017 5:07 pm

Nothing wrong with Michael's suggestion, but you would also be fine either oiling straight onto the top with the bridge area masked, or oiling after gluing the bridge. I've done both and never had a problem - any seepage of the oil under the tape is minimal.

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Re: Oil finish to top - with bridge on, or not?

Post by Douglass Scott » Sat Jul 22, 2017 5:20 pm

Above suggestions sound good. Just want to add that I don't see any drawback to gluing the bridge on first, since it getting in the way is not an issue if you're oiling the soundboard. If you were French polishing the top, the bridge gets in the way big time. So I'd glue it on first to be sure to get the best glue joint possible.

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eno
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Re: Oil finish to top - with bridge on, or not?

Post by eno » Sat Jul 22, 2017 5:35 pm

I used Liberon oli finish recently on back and sides of one of my restoration project and I did not like it at all conpared to FP (that luckily I put on the top), it smells terrible and still stinks after a few weeks, and it looks plasticky. FP is so much better with its aroma and natural glowing look. I will never use oli finish again.
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Mitsuru Tamura No.800 1969

Jon Gillard
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Re: Oil finish to top - with bridge on, or not?

Post by Jon Gillard » Sat Jul 22, 2017 6:20 pm

eno wrote:
Sat Jul 22, 2017 5:35 pm
I used Liberon oli finish recently on back and sides of one of my restoration project and I did not like it at all conpared to FP (that luckily I put on the top), it smells terrible and still stinks after a few weeks, and it looks plasticky. FP is so much better with its aroma and natural glowing look. I will never use oli finish again.
Kevin Aram's GAL article is really helpful, regarding oil finishing, needs cutting back with 0000 wool and can then be micromesh finished to satin or gloss as preferred
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eno
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Re: Oil finish to top - with bridge on, or not?

Post by eno » Sat Jul 22, 2017 11:14 pm

Jon Gillard wrote:
Sat Jul 22, 2017 6:20 pm
Kevin Aram's GAL article is really helpful, regarding oil finishing, needs cutting back with 0000 wool and can then be micromesh finished to satin or gloss as preferred
Yes, I have his article and was following his method. But it didn't help with the smell :D
Paulino Bernabe 'India' 2001
Masaru Kohno No.6 1967
Rokutaro Nakade 1967
Mitsuru Tamura No.800 1969

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Michael.N.
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Re: Oil finish to top - with bridge on, or not?

Post by Michael.N. » Sun Jul 23, 2017 9:10 am

The smell is from the tung oil. It does look like plastic if you build it into a full gloss finish. I guess that it contains polyurethane. It's really no different to many other Danish oil finishes, most of which seem to be based on tung oil. That's the Liberon though, there are plenty of other types of oil finishes/varnishes. Tru oil is based on linseed oil so smells a little more pleasant. Linseed and pine resin (colophony) varnishes smell much nicer.
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Re: Oil finish to top - with bridge on, or not?

Post by Jon Gillard » Tue Jul 25, 2017 9:02 pm

eno wrote:
Sat Jul 22, 2017 11:14 pm
Jon Gillard wrote:
Sat Jul 22, 2017 6:20 pm
Kevin Aram's GAL article is really helpful, regarding oil finishing, needs cutting back with 0000 wool and can then be micromesh finished to satin or gloss as preferred
Yes, I have his article and was following his method. But it didn't help with the smell :D
Need free face mask with next edition :)
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eno
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Re: Oil finish to top - with bridge on, or not?

Post by eno » Tue Jul 25, 2017 10:07 pm

Jon Gillard wrote:
Tue Jul 25, 2017 9:02 pm
Need free face mask with next edition :)
Yes, I used the mask. I can tolerate the smel when I do the finish, but what I don't like is that it still stinks after a few weeks and I smell it when I play it. Hopefully it will go away eventually.
Paulino Bernabe 'India' 2001
Masaru Kohno No.6 1967
Rokutaro Nakade 1967
Mitsuru Tamura No.800 1969

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geoff-bristol
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Re: Oil finish to top - with bridge on, or not?

Post by geoff-bristol » Tue Jul 25, 2017 11:04 pm

Never done a full oil finish - but have always done necks on violin family - 'just the area one handles' - with a shellac seal, several coats. sand smooth and rubbed with tung oil. Straight tung is a natural drying oil ( not sure where the polyurethane thing is coming from ? )

It needs to be rubbed fequently and often. Then once handled it becomes super smooth and good to touch and feel. I do my guitar necks the same - just from the heel area to the nut.
Any oil finish on spruce can be real problem if it absorbs into the wood. It just does not dry well. Seal it with shellac first.

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Michael.N.
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Re: Oil finish to top - with bridge on, or not?

Post by Michael.N. » Wed Jul 26, 2017 7:17 am

The Liberon doesn't act like pure tung oil. I suspect it contains a modern resin like substance (poly) or one of the oils has been modified, perhaps like an alkyd.
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