Thread: Why not polyurathane?

Hi mate, and don't worry I for one won't flame you, afterall, if an item is yours, and you like it, it is also equally your choice of finish to choose.

However, to give you my perspective on such matters, the quick answer is that obviously modern finishes are that, modern, they weren't around in the past and hence in a way such questions can become a little pointless.

The reason why I like, and I suspect most others probably do, is because, such finishes are correct for the period unlike modern poly finishes and yes using such finishes on antiques will devalue a piece. In short it ruins the patina of an old finish on an old piece of furniture or whatever.

Also and from a practical perspective, the problem with modern finishes is that if they get damaged and they can, it is damned hard to repair them without the repairs being obvious, and/or a lot more work. With old finishes such as shellac based, oil based etc, is that they are easy to repair, to repolish them.

Shellac is extremely easy to use, nothing rocket science about it. True French Polishing is also not really difficult to do, it just takes a little work and some experience.

I personally don't like the feel of poly based finishes whereas the sensory feel I get from a shellac/French polished piece to me is completely different and tactile. I also love the look of it. Sure they can be a little more difficult to look after, that is heat, water, alcohol can affect it, ditto it can scratch fairly easily. But on the other hand it is not hard to repair if such damage or wear happens, and ultimately I respect my antiques and so am careful with them. Not all people are though of course.

So that is my take on such things.

Would agree with Horsecroft88 on this. Stuff finished with modern finishes are harder to fix if something goes wrong and look different (there's even a difference between older "modern" finishes like nitrocellulose lacquer and modern polyurethane) and the people who love this stuff, not to mention the dealers, think it makes the object less appealing.

If you're intending for something to be in your home forever and aren't fussed by the perception, then that's fine.

But, the people who buy this stuff, both punters and dealers, see it in equal parts as devaluing the object (or in some cases, destroying it) and occasionally creating an opportunity to buy something really good for pennies because of the non-sympathetic restoration.

Not really a clear finish story but I once saw large Art Deco mirror and frame (mirror intact, manufacturers plate on the back) in a flea market in Paris. It had been spray-painted pale grey. I scratched some paint off and found oak. I got it for 100 Euros ($117).

I managed to ship it back to my (then European) home base in one piece, stripped it, shellaced it and now have something very similar to what I've seen in high-end shops here in Sydney for around $2000 plus.

And I'm just a punter.....imagine how the pros operate.

So, if not for your own sake, then for the sake of your heirs (may they be many but a long way off inheriting) I'd try and stick to the period correct finishes.

And, yes, they are easier to work with which is why most of the dealers still use them, even on stuff that didn't originally have those finishes.

Basically, polyurethane is not an easily reversible finish; to remove or refinish polyurethane generally means sanding back to bare wood, and there's only a certain number of times you can do this before you run out of wood (especially on veneers).

With finishes such as wax, shellac and oil, you can make spot repairs whenever you want to with less effort; they also let you build up the sort of 'passage through time' patina which is so popular on antiques.

Poly also looses its look after a number of years of wear/seasonal cycling and there is no easy solution to overcoming its shabbyness apart from refinishing. Poly might look great for a few years, but it's downhill after that; the older finishes go back to looking great every time you give them a bit of a wax or oil.

Exactly what most have said. Reversibility might not seem good at the moment but the next bloke along could really be cursing you. A luthier who comes on this forum has just finished scraping clean a century (or more) old violin that someone had polyurethaned. If that had been brought in for repair it would have been uneconomic.
Not all old methods were perfect. The use of plaster of paris as a filler is supposed to have been a real problem when associated with thin veneer. It is translucent when it first meets linseed but as the oil oxidises it shows up white again. Sanding is supposedly the only answer.
Always think of the next bloke. That aside, much of the prized patina on old furniture is a mixture of different finishes over the years plus smoke and housemaids' sweat.
Cheers,
jim

OK. Thanks for the replies so far. I was not aware of the fact that poly goes off after a few years and is so hard to repair.

It sounds like I need a quick course on "old style finishing" or "restoring old finishes". Any suggestions?

Walesey

Gee, the main sponsor of the woodwork forums has a book on the subject, that tends to be highly regarded....
A Polishers Handbook

Thanks Master, that sounds like just what I need. I have ordered myself a copy now.

Cheers
Walesey

I have my copy of the book. Now I just have to find the time to sit down and read it!

Cheers
Walesey

No worries Walesey, and if you are unsure of anything, or get a bit stuck, just ask away any questions. In my view there isn't a thing such as a dumb question and there is plenty of experience here and from what I have read, most are really happy to give any practical advice they can. The other thing to do perhaps is check out some of the other restoration threads and/or finishing threads as again there is also plenty of info there which should help. The key to it, is try starting on something small, or that doesn't matter too much. Practice on scraps of wood, or alternative on areas which are not readily seen. It is a learning curve but it generally doesn't take too long to get the hang of the fundamentals. Good luck.