Author Topic: Advice on stripping unknown finish  (Read 272 times)

Online Twisted Trees

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Advice on stripping unknown finish
« on: August 20, 2019, 10:44:18 AM »
I have been given an old mahogany bowl circa 1940's / 50's it has an almost black finish on it from accumulated grime.

Obviously not a professional piece, there are clues! Actually its a bit ugly! with 12mm wall thickness, so I have scope without changing the actual shape to recut the surface.

So far I have cleaned it with white spirit which shows some mahogany trait rather than just black, My temptation now is to sand off the finish and also re-sand the bowl, going to cost in abrasive as it will clog quickly especially if it is varnish, the foot has some damage which I have scope to re-cut.

But before I do, I wondered if any of you had a better approach. It's not old enough to be a hands off minimal restoration, want it back to shiny new finish, and though it is not pretty it's a nice piece of timber that could do with being somewhere for another 50 years before it gets burnt.


Offline bodrighywood

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Re: Advice on stripping unknown finish
« Reply #1 on: August 20, 2019, 11:14:03 AM »
I would go over it with a curved scraper and lightly take the top layer off before abrading. Also make sure you are wearing some sort of mask if possible as finishes from that era were not exactly friendly.

Pete
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Online Twisted Trees

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Re: Advice on stripping unknown finish
« Reply #2 on: August 20, 2019, 11:30:56 AM »
Good plan Pete,  scraper will get me back to the wood quickly, and yes filter mask must be used with old finishes especially unknown ones!

Offline Paul Hannaby

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Re: Advice on stripping unknown finish
« Reply #3 on: August 20, 2019, 02:17:03 PM »
Try methylated spirit and wire wool to remove the old finish and grime.

Offline bodrighywood

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Re: Advice on stripping unknown finish
« Reply #4 on: August 20, 2019, 03:28:35 PM »
Try methylated spirit and wire wool to remove the old finish and grime.

Some of the old varnishes react with meths and can give off fumes. OK to wipe down and get rid of grease maybe but wouldn't advise for removing any varnish or lacquer.

Pete
« Last Edit: August 20, 2019, 11:34:39 PM by bodrighywood »
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Online Twisted Trees

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Re: Advice on stripping unknown finish
« Reply #5 on: August 20, 2019, 09:23:53 PM »
Sorry got grandchild distracted!

I do use Meths but am pretty sure this is not shellac finish, having  plenty of wall thickness I am going with the light scrapper then abrasive on this one, if it was thin walled then I would go with the solvent / chemical generally after cleaning a piece pn the base to see what works out of eye sight first!

This as I said is not a professional piece, has a screwed on plinth to hide the scruffy way it was attached to the faceplate! and that plinth was a solitaire board before it was used as a plinth! just need to put a small bead on that to hide the fact it has been dropped, then I will re-attach with a bit more care than was used previously.

Got grandchild for the rest of the week, but will put up a picture or 2 when it is done.