Antique Mortise & Tenon Joint Question

I am in the process of refinishing a small mahogany dropleaf table that has been in my wife's family since before the Civil War. My father-in-law had it refinished in 1929 and it has seen some very heavy duty since then.

My question concerns the mortise and tenon joints. The legs came off of the skirts relatively easily. I was able to remove the old hide glue from the tenons with a little judicious use of several scrapers.

The inside of the mortises are a different story. I have scraped the walls as well as I could within the limitations of the small size of the holes.

What would be the best glue to use to reassemble the legs and the skirts. I do not want to use hide. :-)

Pinning is also not really a good option.

I usually assemble with Titebond II but was wondering if something like Gorilla would be better in that it would expand and fill any voids left from the scraping and maybe it would adhere better to the insides of the mortises.

Thanks for any light shed on my query.

Reply to
Bill Waller
Loading thread data ...

IMO, it would be a mistake not to use hide glue. You never want to do something to an antique that is not reversible.

Titebond and Gorilla Glue are both poor choices for this application.

Reply to
Lowell Holmes

... and the reason why you are able to "refinish" at this point can be directly attritubted to the glue that was used heretofore.

It's a shame, because that is exactly what you should use if you value the piece. "Titebond" has a liquid hide glue that would not be my first choice for a hide glue, but much better than anything you've mentioned.

Give it (hide glue), some serious reconsideration ... sounds as if the piece deserves it.

Reply to
Swingman

If you want an adhesive that fills gaps, then it's epoxy and micro-balloons, period, end of report.

Forget garbage glue, AKA: Gorilla glue.

Having said that, don't think I would use epoxy or even TiteBond for this piece of furniture.

I suspect you want to stay with hide glue if you want to maintain the value of the piece.

I'd check with an antique restorer before I did anything.

Lew

Reply to
Lew Hodgett

As a matter of preserving the value use hide.

Otherwise I'd try G2 epoxy--it should stick to just about anything, is gap filling, and has enough flexibility that it shouldn't cause further loosening of the joint due to repeated expansion cycles. Note though that if you use epoxy you are _not_ going to get that piece apart again without breaking something, so be _very_ sure you want to use it.

Reply to
J. Clarke

Epoxy with a microballoon filler is regarded as acceptably reversible in museum conservation circles. It's obviously not as easily reversed as hide, but as far as a strong gap filler goes, it's as good as you're going to get.

This situation should almost certainly use hide. If there are gaps, then shim the tenons and still use hide.

Reply to
Andy Dingley

I see a lot of people posting about how Gorilla Glue will "expand to fill gaps".

It sure does, but the expanded glue has almost no strength. It isn't a gap filling glue.

Sorry Bill, you were the one who posted the comment when I felt a bit testy.

Old Guy

Reply to
Old guy

Just curious, "how they do dat"?

Lew

Reply to
Lew Hodgett

Use hide and veneer to reface inside of mortise. Then assemble using hide.

Bill Waller wrote:

Reply to
SonomaProducts.com

If he's refinishing a refinished piece, he's not concerned about value as an antique, but as a piece of furniture. If that's what the restorer/dealer has to say, all options apply. Me for veneer shims and soluble glue for the tenons, though it's hard to believe that they were not pinned in the past. If so, bore out the pins, fill the holes in the tenons with wood and glue, and draw bore the reconstruction to help things along.

Reply to
George

formatting link
conservators reckon that the filled epoxy is suficiently non-adhesive on its own, others apply a barrier coat of Acryloid B-72 first.

I'm sorry about the rest of the day you've now lost to reading back-issues of JAIC 8-) I wish they had up to date ones on that site too.

Reply to
Andy Dingley

Hmm--reading that they say that they're going for shrinkage of the wood resulting in failure of the filler, not the wood. For what they do that may be desirable, but Hoadley suggests, based on his own tests, that for maximum longevity what one really should be going for is a filler with enough elasticity to accomodate shrinkage of the wood without either failing. Hoadley used RTV in his tests--that stuff in my exeperience isn't all that strong and I do wonder if using the same test as they used it could also be separated without damaging the wood (beyond leaving it coated with cured silicone, which in itself is a problem).

Reply to
J. Clarke

Remember that they're museum conservators, not furniture restorers. They're trying to make an exhibit fit for visual display, not make a chair fit to sit on again. They care about reversibility as #1 and looks as #2, but mechanical strength is far behind.

OTOH, I use phenolic microballoons in West System epoxy a lot as my standard filler for "Nakashima like" work. Maybe not chairs, but I've got tabletops that are held together by nothing else and I haven't had any problems.

Reply to
Andy Dingley

I agree, twice-refininshed and the collector-value is likely in the toilet.

Hide glue was used back in the day largely because it's what they had. Modern adhesives are in may cases superior.

If this were a chair, because of the frequence of chair joinery failure and the fact that you (often) have to disassenble the entire thing to fix a single joint, I could see using hide glue. Reversability is important in that case.

By contrast, a leg/apron M&T joint is not likely to ever fail using a modern glue. In fact, it is likely that the original joint failed *because* it was hide glue.

-Steve

Reply to
Stephen M

Maybe not in 100 years.

LOL ... not exactly profound, but hard to argue with. :)

We'll only know for sure in a few hundred years.

Good point.

That's one "ever" that likely can't ever be proved. :)

It could just as easily have been caused by sloppy joinery, improper application of the original glue, bad batch/mix/temp of glue, or a combination of the above.

There are a number of 300+ year old furniture pieces, and musical instruments, still going strong on hide glue.

Reply to
Swingman

Snip.

Or was it the expertly rendered joinery which held together in spite of failing glue?

In any case it's a really good question to which I have yet to get a definitive answer.

Please don't make me cite, because I can't, but....

Aliphatic resin glue has been around for over 50 years. I believe that hide glue has been shown to degrade within that time frame.

It is theoretically possible to simulate age with temperature and humidity cycling and exposure to additional oxygen. Have the Franklin (Titebond) or Elmers guys done this in the lab? My guess is that they have, but gaining access to that data might be tough.

I'll e-mail the Franklin guys and just for grins. I'll probably get nothing but it's easy to try.

-Steve

Reply to
Stephen M

Why? A good restoration with traditional materials and a moderate amount of care doesn't depreciate the value of the piece other than once losing the "original" cachet. If you do it right you can repeat this process as often as you like.

I don't have any furniture more than 200 years old but I can walk into town and see several housefuls of pieces that are pushing 400 years. These have repairs on repairs on repairs, all done with hide glue (A couple are my work). Their "value" depends on their state, not on a simple count of fixes "One's OK but two's only fit for eBay".

Pinned tenons aren't common in chairs and smaller leg timbers. You find them in tables, but a lot of casework won't have them. I'd be reluctant to add draw-bored pins too, because in this width of timber there's a real risk of splitting the hole out sideways.

Reply to
Andy Dingley

Well that was quick, but sadly, uninformative.

Thank you for your inquiry. Our experience with Titebond Original Wood Glue shows that a properly assembled bond will last indefinitely. As you have seen, Titebond Original Wood Glue has been out on the market for over 50 years and we have never seen any bond failures due to the age of the dry glue. I do not have or am aware of any long term studies regarding bonds created with aliphatic resin glues. Creating a strong bond with Titebond Original Wood Glue requires clean gluing surfaces and tight fitting joints. It is also important that clamp pressure is applied along the entire glue line while the glue is still wet and will flow easily. I hope this information is helpful to you.

Sincerely,

Marc Bergdahl Technical Specialist Franklin International

Reply to
Stephen M

Haven't you ever watched the Antiques Roadshow on PBS? If you haven't, go see it a few times. The appraisers will have you singing a different tune. "Losing the 'original' cachet" has a MAJOR impact on an antique's extrinsic value.

Reply to
Just Wondering

Where did he say that it didn't?

Reply to
Swingman

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.