Cross grain moulding
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Hello Paul and all,
New member and first post! I am about to start the restoration of an old family heirloom and would appreciate some advice on best practise. This is a very typical piece of early 1800’s West Indian furniture(Barbados to be exact) which I brought to Switzerland about 10 years ago. Its made of Switenia Mahoganie which was the ultimate furniture wood back then. Still is down there but very protected. The rlative humidity in Barbados is always above 80% and so what happened soon after it arrived in Switzerland was what you see in the photo. It did arrive in the winter months so the low humidity level caused the moulding to contract and every few days pieces of it would fall off. Some in whole lengths and others as seen actually split. What made this more possible was the fact that this moulding is formed on widths of cross grain or in other words the grain is running vertically. It was always done this way on these pieces. The base wood of the seat section is pine and the tropical termites have had a go at that. They would never attack the mahogany which they do not fancy. I have all the pieces of moulding which have fallen off and of course they are cupped. So the big question ? Is there a way to straighten them for reglueing ? Should I soak them before glueing and will they remain flat or want to lift again ? I do have some of this mahogany which I can use to make new moulding but of course I would have to make a moulding plane with the profile shown. I would really like to maintain the original if possible. I thought of back cutting the lengths to relieve the stress however there is too little room for that. Do you think a soaking would help solve this problem.
I would love to have your advice on a solution to this problem. This “Single end couch” is a “Leftie” (back board and armrest to the left) I want to make a right hand version replica so I will have to tackle the task of making a moulding plane soon. Thanks for your input.[attachment file=310420]
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This is just a guess on my part, not expertise: Although the moulding grain is crossed vs. the supporting framing, the widths of both are small, just a few inches. It is surprising that there was enough movement to cause failure, but then again the move in location was an extreme change in moisture. If there were my own piece for my own use, I’d be practical about it. I would declare that the piece has a new home, it has had ten years to reach equilibrium, and that it is done adapting. Thus, I’d make any repairs needed for the supporting frame and then simply reglue the moulding. You could hedge your bet in two ways. First, it looks like the moulding tucks under a lip or rebate that protects it from legs and knees at the top. So, you could choose to apply glue to only the bottom half of the moulding and leave, say, 1/32″, gap between the top of moulding and the edge of the rebate. This will give room for movement. The second hedge would be to use some variant of hide glue, even if it’s ready made liquid glue in a bottle. One advantage to this glue is that it probably matches the historical construction (research that), but the other is that the glue would be reversible. So, if it turns out that this was a bad idea, and there’s too much movement, you could reverse the glue, pop off the moulding, and try something more complicated. Bottom line- I’d just glue it all right back on the frame and enjoy the piece. Refrain from shipping it to the Mediterranean afterwards. You may need to take care to scrape off previous glue to gain access to a good gluing surface.
By the way, there was a period of furniture that is sometimes called the “Walnut Period” in which mouldings were formed cross-grain and then applied, just like on your piece. You could investigate that period to learn what precautions they took and what rules of thumb they had for construction. I’d try to find original descriptions rather than modern descriptions of how people reproduced the look.
Thank you Ed, much appreciate your input. Switenia Mahogany is actually a very stable wood with very little movement but these relaively thin cross grain lengths just could not take the central heating shock. You are right, they have now aclimatised to the situation and should no longer move. My main concern is how to reapply them in their cupped (bowed) state. They might snap when clamped. What do you think of my idea to soak them prior to clamping. The piece is probably 200 years old and that glue was what ever they used back then. I like the idea of using hide glue. Many thanks again.
In order to bend wood, it is usually heated, because that softens the “internal glue” that keeps the fibres together. When the wood cools down while being forced into the required shape, the glue hardens again and the shape is stable.
You could try with a single piece, hold it over boiling water (into the steam) for a few minutes and then see, if you can press it flat.
By the way, I would use hide glue for this project. It is quite as permanent as white glue, except if you want to take it apart. Softening hide glue with hot water is a matter of minutes, while doing so with white glue takes days. I had a plane in a bucket for two weeks, because I had to remove the sole, where I had previously glued one end with white glue.
Being in Switzerland, you might understand German. In that case, look for “Lothar Jansen-Greef” on youtube. He provides a lot of information about using hide glue, applying, removing, using it as a filler, etc. And you might learn other useful things too. And you might realise, that even if a piece of the moulding snaps, it is not the end of the world or even the end of that piece…
Dieter
Yes, that sounds like the way to go….steam heat should get them straight and I will use hide glue for sure. Thanks Dieter for the tip and reference to Lothar. I will check him out. How wonderful is youtube !I have good reason to believe this piece was built by my Great Great Grandfather in Barbados 1802-1867. If I get it right it should hopefully see a few more generations.
JohnI’m not sure what to suggest for the cupping. If you introduce moisture, you may go right back to where you were 10 years ago, but I understand the logic of trying to reform the back to flat.
The piece in your photo doesn’t look very cupped. If it isn’t very much, could you flatten the back of the moulding, glue up, and then either live with the discontinuities in front surface or scrape them to a consistent contour and repair the finish? That may be more invasive than you want for a piece you want to preserve as close as possible to the original. If it’s cupped, I guess the front surface isn’t going to be perfect in any case, but that’s not necessarily bad. It’s part of the history of the piece.
I should start by saying if this is a treasured family heirloom, you should probably take it to a professional furniture restoration business, not experiment on it.
But if you’re set on proceeding yourself, I do think making your own molding plane with that profile is a very good idea. You’d then be able to make perfect molding, dead straight, and even better, if the chair sustained further damage to the molding some years down the road, you could then always make more to fix the damage, and more molding planes are always a Good Thing 🙂 maybe you’d use the profile in future pieces. Also, if your ancestors built it, it’s appropriate that you also build some part of it, to continue the tradition.
I’ll say steaming has a risk. When you steam already-finished wood, sometimes the finish cam partially leech out, and usually in a very uneven way. The result is horribly ugly half-finished, blotchy wood, and it’s very difficult to get it to look even ever again. If you had a test piece I’d say test it, but obviously there are no 200 year-old test pieces (right?). If you’re going to sand the moldings down to bare wood and re-finish, then this isn’t a concern.
If steaming is too much of a risk you could try dry heat. There are youtube videos showing how to use cheapie propane torch (like this: https://www.amazon.com/Bernzomatic-TS3000T-Quickfire-Self-Igniting-Torch/dp/B00008ZA0B) and heat the inside of a pipe or empty metal can clamped in a vise. Just leave the torch on, continually heating the can while you work. Press the piece firmly against the pipe / can / whatever, and it’ll quickly get hot enough to where it’ll bend. Don’t press the show side in case of burns, but the heat might still damage the show side, FYI. Get it close to straight, then quickly clamp it to a perfectly straight surface that is very strong before it cools. If you’re going to use hide glue, you need this extra step (clamping to a straight surface to straighten the wood after heat as opposed to clamping and glueing to the piece itself) because the level of heat needed to bend wood will undo hide glue. Once it’s cooled, prep everything for the glue-up to the chair, and take the molding from the clamps and back into the glue-up clamps as quickly as you can, because the piece will spring back a bit once it’s out of the clamps, so don’t give it the time to warp even a little bit.
You may need to gap fill with epoxy or other pigmented wood filler. Epoxy can stand the heat needed to bend wood, not sure about commercial wood filler products.
Just some thoughts — best of luck, and keep us posted with the results!
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