tongue and grove instead of jointing board.

[Kevin McMichael]

I am building a large tool chest out of cypress. I bought some very rough shorts for the project and have started to plane the boards for glue up. Would it be practicle to tongue and groove the boards and glue them up? I have never heard of anyone gluing a tongue and grove joint...why not? It would give more gluing surface.

[Derek Cohen]

Hi Kevin

There is no reason I am aware of that says you cannot do as you plan - although I do not see a reason to do so in the first place, unless you are thinking that the t&G will act like biscuits to keep the edges flush when joined. Be aware, however, that you do need to joint each board first simply because the edges still need to be joined - and the edges of the boards formed are referenced from the jointed edge. The whole idea of a T&G joints is that it is designed for movement, and not to be glued.

I once (about a dozen or more years ago) made a sideboard top this way. But since then have only used this method to float a butt-joined panel, such as ...

http://www.inthewoodshop.com/Furnitu...tedChests.html




Regards from Perth

Derek

[Chris Hachet]

I am building a large tool chest out of cypress. I bought some very rough shorts for the project and have started to plane the boards for glue up. Would it be practicle to tongue and groove the boards and glue them up? I have never heard of anyone gluing a tongue and grove joint...why not? It would give more gluing surface.

It is probably overkill to do this... I have four teenage children living in my house and my kitchen and family room furniture sees amazingly hard use...I have yet to have something come unglued.

I have glued up panels with plain butt type joints for work shelves...If a four hundred pound refrigeration compressor or the short block to a small block Chevrolet bee eight does not kill a butt style glue joint , I am not sure what will.

[Chris Hachet]

Oh, and nice score on the cypress!

[Stanley Covington]

In response to your question "I have never heard of anyone gluing a tongue and grove joint...why not?:"

I understand you reasoning. I suspect most woodworkers have had the exact same thought at some time. I know I tried it once.

Here's the reason: Literally thousands of years of history, and lots of modern academic and industry studies, have shown that two seasoned and stable boards properly jointed, edge glued, and clamped, have more strength than the wood fibers themselves. This means that, in most cases, a board made from two properly edge-glued boards will be stronger than a single board of the same width. Modern glues have nothing to do with this.

"Properly" is the critical qualifier.

A T&G joint adds a discontinuity in the glue line that can actually weaken the joint. And a T&G joint is much more difficult to fabricate to the level of precision necessary to develop the same psi strength in the glueline as can be achieved with less effort and material using the ordinary edge-glued joint.

But materials science aside, if you like T&G joints, have fun. Just remember that the T&G joint's advantage lies in its ability to assemble long boards edge to edge while allowing for expansion/contraction, and controlling warping, all while keeping out dust and bugs. A wonderful joint indeed. But glue does not improve it in its classical role.

Stan

[Lonnie Gallaher]

I have a mid-twentieth century maple chest of drawers that was made by a high end factory that all of the case and drawer fronts have T&G joints. I do not remember the maker, but the maker's furniture does have a collector following.

BTW, the glue joints in the top are starting to fail.

[Jim Koepke]

That makes me the odd man out. I have glued T&G joints.

Maybe it was just because I was having fun with the match cutter on a Stanley 45.

Mostly my use has been on long boards for large projects.

jtk

[Stanley Covington]

That makes me the odd man out. I have glued T&G joints.

Maybe it was just because I was having fun with the match cutter on a Stanley 45.

Mostly my use has been on long boards for large projects.

jtk

What were the long boards used for?

Stan

[Jim Koepke]

What were the long boards used for?

Stan

Book shelves and a storage locker.

jtk

[Frank Drew]

If the ends of the glued-up panels will show, I think a simple butt joint looks better than even a perfectly fitted tongue and groove joint; strictly personal taste, I know.

[jamie shard]

In response to your question "I have never heard of anyone gluing a tongue and grove joint...why not?:"

I understand you reasoning. I suspect most woodworkers have had the exact same thought at some time. I know I tried it once.

Here's the reason: Literally thousands of years of history, and lots of modern academic and industry studies, have shown that two seasoned and stable boards properly jointed, edge glued, and clamped, have more strength than the wood fibers themselves. This means that, in most cases, a board made from two properly edge-glued boards will be stronger than a single board of the same width. Modern glues have nothing to do with this.

"Properly" is the critical qualifier.

A T&G joint adds a discontinuity in the glue line that can actually weaken the joint. And a T&G joint is much more difficult to fabricate to the level of precision necessary to develop the same psi strength in the glueline as can be achieved with less effort and material using the ordinary edge-glued joint.

But materials science aside, if you like T&G joints, have fun. Just remember that the T&G joint's advantage lies in its ability to assemble long boards edge to edge while allowing for expansion/contraction, and controlling warping, all while keeping out dust and bugs. A wonderful joint indeed. But glue does not improve it in its classical role.

Stan

+1 Great reply Stan!

[Don Dorn]

If the ends of the glued-up panels will show, I think a simple butt joint looks better than even a perfectly fitted tongue and groove joint; strictly personal taste, I know.

Agreed. That is the only reason I don't use the T&G. On larger glue ups, I used to use biscuits just for the sake of alignment, but even that prevents me from "rubbing" them together to create the suction that I believe is necessary for proper edge gluing.

[lowell holmes]

What's neat about this hobby is that you can make the joint you want to. If you want t&g joints, do it.

I would make it a simple glue joint.

I don't use biscuits either. I have large jar full of biscuits and a biscuit jointer I never use.

A few grains of sharp sand in the glue joint will keep it aligned while clamping.

[Chris Fournier]

No real need so I'd avoid the trouble and lavish joinery on another detail in the project.

[Stanley Covington]

A few grains of sharp sand in the glue joint will keep it aligned while clamping.

Now that's one I haven't heard before. I suppose it would work brilliantly, but does the sand in the glue line cause problems with plane and planer blades, or do you use a surface sander after glue-up?

Thanks,

Stan