Suggestions on Loose vs Traditional Tenon Bench/Breadboard

[Ryan Tea]

Hello all,

I have completed a farmhouse table made from reclaimed chestnut for the top and soft maple base/legs. I want to compliment the piece with some nice benches that look the same, but was interested in attempting loose tenons this time. It took me forever to hand cut the mortises in the 5 inch legs, and quite some time for the breadboard M&T.

So my questions are, I am about to pull the trigger on the Festool 500 or 700.

- Would the 500 be sufficient if I do two tenons on a 1" soft maple apron into a 3" soft maple leg?

- Same question if the 500 would be sufficient for 3" breadboards on 1" thick bench seat top in Chestnut?

The overall benches will be 82"L x 14"W (Two pieces of 7") x 1" thick.

I think the usual M&T calculations won't be perfect for the 500, but I wanted to start out with a much less priced tool if possible.

Thanks!

[Chris Padilla]

If you were to use traditional M&T joints for this, what size would they be? I would find a domino that is as close to that as possible and you'll have your answer as to which machine might serve you best.

[John TenEyck]

Cut the mortises with a spiral up cut bit in your router with an edge guide or collar and template for whatever size loose tenon you desire, and save yourself $1200.

John

[Wayne Lomman]

Why do loose tenons at all? This is not a substitute for traditional mortise and tenon. It is a lower grade substitute for where there is no alternative. John is right - save some money. $1200 buys a lot of timber. Cheers

[Bill McNiel]

Ryan,
Direct answer to your question, the 500 will do quite nicely for your project.
regards-Bill

[Ryan Tea]

Why do loose tenons at all? This is not a substitute for traditional mortise and tenon. It is a lower grade substitute for where there is no alternative. John is right - save some money. $1200 buys a lot of timber. Cheers Well that's no fun....How else am I going to justify to my wife that this is a tool I NEED to get her project done? Haha.

[Ryan Tea]

Ryan, Direct answer to your question, the 500 will do quite nicely for your project. regards-Bill


Thanks Bill !!

[Dimitrios Fradelakis]

You can buy the 700 and use the adapter from
Seneca Woodworking to work with the 500 cutters.

[Jim Becker]

Ryan,
Direct answer to your question, the 500 will do quite nicely for your project.
regards-Bill
While I agree, I'd still suggest the 700 for long term flexibility...and there's a third party adapter system to use all but the smallest 500 cutters for the "small stuff".

[Chris Padilla]

Why do loose tenons at all? This is not a substitute for traditional mortise and tenon. It is a lower grade substitute for where there is no alternative.

And how did you arrive at that, Wayne? Assuming the traditional and loose are EXACTLY the same size, why wouldn't they be equal?

[Chris Padilla]

While I agree, I'd still suggest the 700 for long term flexibility...and there's a third party adapter system to use all but the smallest 500 cutters for the "small stuff".

I jumped for joy when the 4 mm came out. I'm guessing this is the one that the 700 can't handle?

[Chris Padilla]

And Ryan, do a search in here on: domino 500 700

There are some very good threads discussing this very topic.

[Ryan Tea]

And Ryan, do a search in here on: domino 500 700 There are some very good threads discussing this very topic. Thanks Chris, I've been reading. I am also familiar with the Seneca adapter. Unfortunately I think I'm being that guy who had to post just for reassurance. I wanted someone to tell me that id be fine with the 500 and not spend the additional money. But I know deep down I should probably bite the bullet and get the 700, it just has that depth I've always wanted.... :/

[Wayne Lomman]

And how did you arrive at that, Wayne? Assuming the traditional and loose are EXACTLY the same size, why wouldn't they be equal?

Chris, loose tenon has double the reliance on glue, there is no continuity of timber fibres, there is twice the clearance error. Loose tenons may be fine if your reputation for excellence isn't on the line with every job. Cheers

[Wayne Lomman]

Further to the above, I will not offer on this forum anything other than the best advice I can based on my lifetime of experience. Whether anyone takes notice of it is not my problem - experience tells me it won't be many - but it will still be based on experience and learning, not opinion. Cheers

[glenn bradley]

Cut the mortises with a spiral up cut bit in your router with an edge guide or collar and template for whatever size loose tenon you desire, and save yourself $1200.

John

I am with John on this.

344109 . 344110

344112 . 344111

The domino is a cool tool but, I have been routing mortises for so long its a non-issue.

[Art Mann]

I have done mortises, pegged or wedged through mortises, dowels and even pocket screws at different times. I say strong enough is strong enough. If you replace a joinery method that is 3 times stronger than necessary with one that is 5 times stronger than necessary, you haven't increased the value of the piece you are making at all. There is a place for all these joinery methods. Don't go to more trouble than is necessary for the job at hand.

[Robin Frierson]

Well I broke down and bought the 700 and am making some drawer cabinets now with it for my new shop. I recently did a test joint with it on a single 8mm domino and was surprised to see how easy it broke when I put some pressure on it. Snapped right in half. Of course with this lower case I am building there with be 5 rails holding it together so I will be fine. But the jury is still out on this tool for me. I couldn't fit two dominos on the size stock I had. If i was doing traditional I would have had a tenon about 2.5 times the size of this domino. But I suspect it will good enough for what I am doing. Pocket holes would have worked too and been a lot cheaper.

[Chris Padilla]

Chris, loose tenon has double the reliance on glue, there is no continuity of timber fibres, there is twice the clearance error. But the glue is supposedly stronger than the wood...especially modern glues. So I don't see a failure of the glue as a reason why traditional might be better than the loose. Is glue failure a common issue?

[Chris Padilla]

Well I broke down and bought the 700 and am making some drawer cabinets now with it for my new shop. I recently did a test joint with it on a single 8mm domino and was surprised to see how easy it broke when I put some pressure on it. Snapped right in half. Of course with this lower case I am building there with be 5 rails holding it together so I will be fine. But the jury is still out on this tool for me. I couldn't fit two dominos on the size stock I had. If i was doing traditional I would have had a tenon about 2.5 times the size of this domino. But I suspect it will good enough for what I am doing. Pocket holes would have worked too and been a lot cheaper.I think a more valid check would be to make a traditional and loose of the exact same size and then try your test. As you stated, your traditional would have been a lot bigger than the smaller domino and this is in fact why traditional is probably a much better joint as one is severely limited in size with the Domino.

[glenn bradley]

Chris, loose tenon has double the reliance on glue, there is no continuity of timber fibres, there is twice the clearance error. Loose tenons may be fine if your reputation for excellence isn't on the line with every job. Cheers


But the glue is supposedly stronger than the wood...especially modern glues. So I don't see a failure of the glue as a reason why traditional might be better than the loose. Is glue failure a common issue?

Right. the joint tests articles that were everywhere for awhile showed the failure at the joined piece, not the floating (or regular) tenon. It was interesting how the beadlock was always weaker. The nice flat face of a tenon allows a good grip I guess. I only use floating tenons when I am making the mortises by machine so alignment errors are not an issue. YMMV.

[Wayne Lomman]

But the glue is supposedly stronger than the wood...especially modern glues. So I don't see a failure of the glue as a reason why traditional might be better than the loose. Is glue failure a common issue?

Chris, glue failure is more common than you might think. It keeps me in work doing repairs. The failures are sometimes the product and more often the way it was used. The common mentality seems to treat gluing like welding which is totally unrealistic. Glue is a clamp to stop movement in an otherwise structurally sound joint. The exception is if you use a structural glue such as urea formaldehyde or epoxy.

Anyone is entitled to use loose tenons as much as they like but it would be wrong of me to promote them as the best way to construct the joint because they are not. And I have not even touched on the engineering principles.

Off to work now. Cheers

[Marshall Mosby]

Spiral up cut will definitely ease you with mortise cutting.

[Mike Cutler]

Ryan

Either would do it. I think the 700 would be a better option especially if you continue to do projects of this size.

As to the loose versus traditional tenon argument, Look up the posts and threads by Mark Singer. Mark used a very elegant and easy to make loose tenon of his own style. His method is very flexible, and can be adapted to any project.
Mark is/was a very accomplished, and recognized architectural design engineer. He made fabulous houses and furniture that few have the talent to replicate. If I was going to incorporate loose tenons, it would be based on his method
I'm actually not a huge fan of the Domino, even though I have a few of their tools, and I'm a traditionalist when it comes to M&T joinery, but Mark's loose tenon method puts all of the structural integrity back into the joint.
Loose tenons, like traditional tenons, have to follow the rules, or they will fail. In a structural application they need to be pinned, or wedged to ad mechanical integrity to a joint. Glue alone really isn't sufficient for a structural joint.

Wayne
I've done a few restoration also and I've seen just about every type of joint fail in time. A joint should always have structural integrity, because the glue will one day, maybe decades or centuries down the line, fail.
I understand where you're coming from.

[Robert Engel]

Although I agree there is no subsitute for a traditional M/T, I use a mortising machine so I have no dog in the fight.

I have considered a Domino so the pros/cons are of interest to me:

I would say Wayne is correct - yes, glue does fail - but for any kind of joint, even a traditional M/T.

Someone mentioned the size limitation using Dominoes - this could be a problem, albeit a rare one..

As for strength, that depends on the application. I wouldn't use Dominoes to build a chair, for example.

Chris is also correct, glue is stronger than wood. Plus, with a floating tenon 1/2 will be long grain/long grain glueing.

IMO a Domino suits a production shop, not a hobby shop. If an expensive tool spends most of its time on the shelf, then its an expensive tool on a shelf......

I would much rather spend the money on lumber.

[Jim Dwight]

I do not own a Domino but I disagree with the position that a loose mortise and tenon, made by a domino or otherwise, is inferior to a traditional mortise and tenon. It does give you two opportunities to mess up the glue application but if the one side of a traditional is messed up, the joint will fail. And if you do it right, the loose mortise and tenon is as strong. FWW tested joints of the same size in both and got essentially the same joints (I think the traditional was a few lbs higher strength but I believe it is within the accuracy of their tests).

The biggest advantage of the loose cut by a domino is the sides will be relatively smooth and not crushed. A mortise cut by a dull chisel, in a mortise or hand, will have sides that will leave gaps against the tenon affecting strength. It is also more challenging to get shoulders of the tenon which meet the mating piece precisely. I like my shoulder plane and it helps a lot but it is still very possible to have a slight gap - preferably on the inside. It is easier to get a good fit with a domino. But if both are cut correctly, they will be equally as strong.

I've seen failed glue joints too but not with modern glues. The furniture I've made is only decades old but there are no joints with glue failure. I do not believe glue failure is a significant risk with modern glues (I use Titebond II or III).

The only real disadvantage I see for the Domino is the size of the loose tenons. If you have a 500, you can get mortises only about 1 inch long. That is not what I would prefer for a table to apron joint. Or a passage door joint. It should be enough for a cabinet door but for a large one I would prefer a longer tenon. With the 700, it will make mortises nearly 3 inches deep so it should be fine for almost any woodworking. But the loose tenons are, at most about an inch wide. You can use more than one, or make custom tenons but the machine is set up to make the little 1 inch wide mortises. For a cabinet door with 2 inch or 2.25 inch wide frame, you can't easily use more than one so your tenon will be significantly under the size a traditional joint would have been. For the chairs I make, I think the dominos would work. But for some other furniture, I think I would be stuck with having a smaller joint than I want or going back to a traditional mortise and tenon. The machine is expensive, especially if it isn't always useful. But they look nice and I will probably end up with one - probably the 700 with the Seneca adapter and some smaller 500 cutters.

[mreza Salav]

I have done many M/T joints (by hand and dado on table saw), some used spiral router bit with a jig, done thousands of dowels, got Festool 500 and it worked great for all the projects I used it for. Sold it and got the 700 as it can do almost everything 500 can do and can do bigger tenons.
Every joint has its own place. For the entry door I built for our house I used traditional M/T but for vast majority of the other joints you can substitute a floating tenon (like domino).

[Mike Henderson]

I've fixed a lot of chairs and I've not found one where the glue failed. What happens is the wood fails because the glued surface area is not sufficient for the force on the joint. When you take apart a chair that has a failed dowel joint, what you find is that there is wood attached to the glue on the dowel. The wood just comes apart from the forces on the joint. The glue really is stronger than the wood.

A well made joint with a modern glue is plenty strong. If you take a chair that has M&T joints, you rarely see a joint failure, and if you do, it's due to the wood failing, not the glue failing.

I agree with Mel that a loose tenon is plenty strong enough for M&T joints, if it is properly sized and properly fitted.

And once you get a Domino, you'll find that you use it on almost every project. Sure, you can use a router but the Domino is FAST, easy and accurate. And, of course, that's why so many people have purchased them.

Mike

[Wayne Lomman]

To put the function of the mortise and tenon in perspective, think how it functions without glue as in pegged mortise and tenon. You can construct an entire building with unglued mortise and tenon. It won't work with loose tenons - over time the mortise in the end grain gets wedged apart by the loose tenon and the structure sags. It comes back to the point that loose tenons can do a job but don't kid yourself that they are the best. Cheers