# Acceptable cross-grain joint length



## meskin (Sep 22, 2020)

I am restoring an antique camera, which is basically a box, constructed out of 1/4" mahogany. The problem is that it has two long (6") cross grain joints, which seem to have either separated or were never glued all the way on purpose. I am not sure if I should glue them up or leave as is. Maybe it was not glued all the way to keep the camera from self-distracting by cross-grain movement. The odd thing is that it was originally covered by leather, and the leather was laterally torn along this joint on the left side of the camera! - like the vertical board shrunk and took the glued-on leather covering along with it.

What is the acceptable width for the cross-grain joints like this? I know that jewelry boxes sometimes are constructed in a similar way, and do not fall apart from wood movement. Please see attached photos. Any advice will be greatly appreciated.


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## Phil32 (Aug 31, 2018)

My understanding is that shrinkage is greater in the cross-grain direction. The damage to the leather covering was probably unrelated to the wood movement. I have a current project with a cross-grain joint more that twice the length of your example.


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## meskin (Sep 22, 2020)

Maybe the best course of action is to glue it up using a very flexible glue, like E6000? Not sure how it would adhere to the original hide glue, but it's super-stretchable, and might just keep up with the movement.


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## Loren (May 30, 2008)

Leather cracks and decays when unhydrated for many years, unlike wood. Wood cracks for other reasons.


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## Unknowncraftsman (Jun 23, 2013)

It does look old . 
I would consider that joint a success and leave as is. If you did take it apart you should be able to see if there was glue on part of the joint. But it might not be necessary anymore well seasoned wood eventually gives up its fight.
Good Luck


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## rwe2156 (May 7, 2014)

I would run some CA glue in and call it a day.


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## meskin (Sep 22, 2020)

Thank you so much for all the advice! I will probably use a little bit of either CA glue or e6000 - something flexible, and maybe a tiny wood screw or two. The new leather covering should help also.


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## bilyo (May 20, 2015)

I may be too late but, I'll offer my 2 cents anyway. First, I assume that the camera will no longer be used and will "live" from now on in a climate controlled area. If so, I would leave it alone. Usually, I would not think that a 6" panel would expand/contract enough to be of any concern. However, my guess is that, as a camera box, it has probably been subjected to some fairly extreme changes in temp/humidity while going indoors and outdoors from season to season. I think, as a result, it has taken it's toll on the glue and half of it has failed. However, the T&G has done it's job and has held the joint together. I think that adding glue to the joint now, without first taking the joint apart and cleaning it up, will not be effective as I don't think it will adhere to anything. Also, adding screws or nails is more likely to result in splits due to restricting the small amount of wood movement there is. I don't think a repair is necessary but, if it were, the proper way would be to take it apart, clean it up, add hide glue to the center 2-3 inches, and maybe add some pegs in the glued area. Done.
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## Lazyman (Aug 8, 2014)

As long as they are the same type of wood and the same grain orientation, both pieces should have very similar expansion with moisture changes and with only 6" it any variation would be negligible. Even much wider pieces should not break a joint if same wood and orientation. If the T&G has no other dowels or fasteners holding it together and it doesn't just slide off, it must have some glue on it. Can you move it at all? Fasteners could be on the inside. Does the other side have a similar crack?


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## meskin (Sep 22, 2020)

The grain orientation is vertical on the bottom piece and horizontal on the top piece. The bottom panels have visibly shrunk, - by about 1/32". There is clearly a separation in the front of the joint, - the bottom sides are pulling away slightly. They could have come unglued when the camera was dropped some 70 years ago, or it may have never been glued at full length of the joints. Taking the box apart is out of question because it's like a maze inside, - with some mind-boggling super-delicate joinery. After an extensive deliberation, I decided to use a small amount of e6000 glue, just on the front of the camera, on both sides. I hope it sticks. It will be drying for 72 hours.

I experimented with e6000, - glued two pieces of plywood. the glue area is just over a square inch. It holds strong, but is incredibly flexible, - I can see movement of about 1/16" when I try to rotate them against each other! I hope this is flexible enough.


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## Lazyman (Aug 8, 2014)

It sounds like they built it sort of like a breadboard end on a table or cutting board where they typically only put glue on the middle of the joint? Can you see any dowels or fasteners holding it on?

Just how old is it. If it predates about the 1930s it has a high likelihood of being constructed with hide glue which is reversible, though the complexity you mention could make that a bad idea. I personally would not use a modern glue to repair an antique like that unless there is no other way. I've never used E6000 but that doesn't sound like the right glue for this to me.

What exactly is your goal? Are you doing a full restoration to make it functional or just making it look good? Any info on the brand or model?


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## meskin (Sep 22, 2020)

It's from the early 50's. Assembled with hide glue, for sure. There are parts that may be holding it from the inside, also, the leather covering adds some strength. I do not see any dowels - it's a tongue and groove joint. The woodwork in this camera is a little too advanced for me. The model is a 3×4 Graflex RB Series D. I do hope to restore it for use. Bought it as a "parts' camera years ago, hoping to fix it. somebody attached a metal bracket with big screws, placed right on the joint, which also added to the destruction. It was dropped, and had some bad damage to the gear box, but I managed to unbend it. We'll see how it goes - fingers crossed. People still use them.



> It sounds like they built it sort of like a breadboard end on a table or cutting board where they typically only put glue on the middle of the joint? Can you see any dowels or fasteners holding it on?
> 
> Just how old is it. If it predates about the 1930s it has a high likelihood of being constructed with hide glue which is reversible, though the complexity you mention could make that a bad idea. I personally would not use a modern glue to repair an antique like that unless there is no other way. I ve never used E6000 but that doesn t sound like the right glue for this to me.
> 
> ...


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