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By Dokkodo
#1198327
How do. I realised yesterday, I know very little about the world of finishing.

I have carved (rather than turned) a yew bowl out of end grain, quite difficult but after scraping and sanding and an initial finish layer, its nearly there.

I applied first a thick coat of osmo, let it soak in, then rubbed it out. Then I applied another thinner layer of osmo, and rubbed that out.

The areas that have taken a nice satin sheen look great, but its far from even, the disparity seems to vary with the grain, less satin where its slightly more porous and vice versa.

I know osmo comes recommended at two coats, can I try another thin one? Or should I move to a final paste-wax layer of some sort, will it be as durable as whats beneath. Ideally itll be food friendly in case this becomes a fruit bowl.

Thanks, be real nice not to have to scrape it all back off, already done that once!
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By custard
#1198502
End grain needs many coats, and the full drying periods between coats, before it stops drinking down the finish. Don't bother thinning, full strength and keep at it.

Yew has a difficult finishing reputation at the best of times, but take comfort in the fact that time is the great healer with Yew, after a few years it will turn the most glorious and deeply patinated tone.

Over Christmas I was visiting my mother and she still has the very first windsor chair that I made back in the late 80's. The spindles are Yew and even though they probably looked a bit bland when first completed, the finish just keeps improving every year

Windsor-First-04.jpg
By Dokkodo
#1198531
Wow lovely chair that :)

Thats good to know, ill let it dry and keep layering up with thin coats until its consistent. The grain colour and texture is already lovely so its great to think itll just get better and better.

Thanks custard
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By will1983
#1198834
You could try wet sanding the surface with 400 grit wet and dry. Apply your Osmo and then sand the surface using the oil itself as the lubricant. Once the required period of soaking in time has passed just wipe it off as per usual. Apparently the resulting oily paste will fill the pores and help the finish to build.

Also when applying oil I try to keep the whole surface wet, reapplying as necessary to those spots that soak up the oil faster than others. This uses more oil but ensures that the thirsty areas always have plenty of oil available to absorb.
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By custard
#1198897
will1983 wrote:You could try wet sanding the surface with 400 grit wet and dry. Apply your Osmo and then sand the surface using the oil itself as the lubricant. Once the required period of soaking in time has passed just wipe it off as per usual. Apparently the resulting oily paste will fill the pores and help the finish to build.

Also when applying oil I try to keep the whole surface wet, reapplying as necessary to those spots that soak up the oil faster than others. This uses more oil but ensures that the thirsty areas always have plenty of oil available to absorb.


I'm sceptical for two reasons.

1. There's a similar technique in traditional french polishing using pumice powder as the abrasive. That works beautifully because you build up an amalgam of ultra fine saw dust, pumice and shellac which sets like concrete. I'm not convinced Osmo and sawdust on their own would form such a durable amalgam.

2. There's a short cut in french polishing where you save time by filling the grain with plaster of paris, oil over it, then apply the shellac. The problem is that after several years the oil migrates out of the plaster and into the wood, leaving white specs in the grain. I'd be concerned that Osmo and sawdust might behave the same way, with the oil migrating into the furniture and the sawdust falling out or looking pale.

If Percy Snodgrass is reading this I'd be interested in his opinion.
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By will1983
#1199044
Custard, this is a technique used in the world of guitar building quite regularly. I did say "Apparently" however as I to am a little sceptical about its effectiveness.

I recently oiled some beech with tung oil and decided to give it a try however as I didn't do a control piece without the wet sanding I am unable to say just how well it worked. The end result was a very smooth tactile surface however and all the pores seem to be filled. I suppose if you were working on a heavily pored timber it cant hurt to give it go, after all, it gives you something to do whilst the oil is soaking in..
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By El Barto
#1199052
custard wrote:Over Christmas I was visiting my mother and she still has the very first windsor chair that I made back in the late 80's. The spindles are Yew and even though they probably looked a bit bland when first completed, the finish just keeps improving every year

Windsor-First-04.jpg


What a beautiful colour. Don't suppose you have any earlier photos of it to compare how it's aged?!
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By custard
#1199078
I don't I'm afraid, but the trajectory of Yew goes something like this.

The Yew in my timber store typically looks like this,

Yew-03.jpg


This is after a few years air drying, freshly sawn Yew is a bit more orange and actually quite garish.

Add a hundred years or more of oxidation and regular polishing and Yew magically turns into this (not mine unfortunately, just Yew antiques randomly pulled from the web),

Windsor_Ch_as437a1260z-4.jpg


windsor-chairs_11904_pic6_size3.jpg


It raises an interesting question. When you're finishing are you more concerned with how your work looks when it first leaves the workshop, or how it'll look decades later? If you take the long view then there are certain timbers and techniques, like Black Walnut and cellulose, that you'd probably avoid; but there are certain timbers and techniques, like Yew or virtually any fruitwood and french polish, rubbed varnish, and traditional waxing, that you'd embrace with open arms.
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By custard
#1199122
marcros wrote:is there a way to speed up that oxidation?


Yes.

Restorers don't fret too much about replicating polished surfaces, the bigger challenge is the unpolished surfaces like backs and undersides.

Yew responds very well to light and intelligent distressing, a base treatment of dilute Nitric Acid, neutralised, followed by spirit stains and pigments, polish then waxed. Just ignore all the guff you read about pig's urine and dragging behind cars over cobblestones.
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By marcros
#1199140
Thanks custard. What does each part of that do?

Nitric acid to lighten it a little, dyes to add brown and pigments to catch in the grain?
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By custard
#1199172
Not quite, the purpose of the acid is to oxidise. Let me illustrate what that means.

Here's some Cuban Mahogany, at the top is a board I bought at auction, it was originally landed in this country in 1908 and had been untouched in dark timber sheds for over a hundred years (I won't bore you with the story here, but it's a great tale of timber treasure hunting). Below it is another board from the same shipment, that I re-sawed sometime in the 1980' or 90's.

Cuban-Mahog-1980's-1908.jpg


Here's some more Cuban Mahogany from the same original source. At the bottom is a board I resawed in the 1980's, at the top is a board a planed down about two years ago,

Cuban-Mahog-80's-2-Yrs.jpg


So all these samples are from exactly the same original source, they've all lived in the same gloomy timber sheds away from direct light, and they're all unpolished. The marked difference between them is basically down to surface oxidation. Dilute nitric acid gives you a century of oxidation in an afternoon. However, it's initially too flat and uniform. So then you have to build up highlights and darker areas, grime in quirks and hollows, high gloss on proud areas, etc, etc.