Mortise & tenons Cutting accurately

[johnnyb]

I like Derek's tenon jig but like my leigh fmt it struggles with decent depth tenons(my fmt struggles at 35mm and is more comfy at 25mm.)
Using a top notch razor sharp saw is a prerequisite thus ruling out many shade tree woodies. Door through tenons are nearly always over four inch and traditionally were sawn in with a rip saw which made short work of this job and are easy to sharpen. A tenoner makes this cut easy (albeit in three passes) and although common in the uk they seen almost non existent in many places hence the heath Robinson methods suggested. I find control more important than speed. So I hate sawing tenons say 16 in your case then finding out every one is out in the same way(s) and the doors are twisted/bent/ etc

 

[aebersold]

If you are cutting the shoulders on a sliding chop saw, with no problem , then why not the rest of the tenon?
Failing that it shouldn't take too long to cut them by hand, if there are only four doors. After all this is what the tenon saw is for.
Careful marking out, of course is key to getting them all the same.

Fair point, but with 100mm tenons and a 2mm blade, it’s a lot of passes. A tenon saw is also a possibility, if I had one, but was looking impatiently maybe, for speed and accuracy. The marking out of all tenons, as Jacob and yourself have noted will be done in future. Thanks

 

[aebersold]

TBH I've never used a chop saw. Can you cut tenon cheeks with one?

You can quite successfully with a good quality blade. My chop saw has a feature operated by a toggle lever, to set the blade height. The finish is good and acceptable although for me, nothing seems as crisp as a sharp shoulder plane. You must however remember to flip the toggle lever otherwise you make a full cut and cut the tenon off. Ask me how I know

 

[hlvd]

I’m making 4 oak cupboard doors for my hallway and in the process of cutting haunched, wedged mortise and tenons. I’d be interested to learn the quickest way of cutting tenons accurately without owning a dedicated tenoning machine please if anyone has the knowledge ? I cut the mortises with a mortiser and they’re fine. I used my old startrite 352 bandsaw with a 3/4” rip blade, set it up with blade 90 to table, high tension on blade, spent some time adjusting the high fence parallel to blade, but the tenons I cut need so much fettling to get an accurate fitting joint. I cut the shoulders on a sliding chop saw and they’re fine. My spindle moulder is US at the moment and I’ve never used it to cut tenons. Would that be a better more accurate solution….and faster, or am I doing something wrong with my bandsaw ?
Alex

You can get perfect tenons using this technique if you’ve only got a bandsaw. It works best with a vernier caliper as a mortise gauge won’t be accurate enough.

Rip your tenons 0.25mm thicker in the first rip.
Cut your shoulders.

Clamp a piece of square end timber to your bandsaw table, making sure it’s touching the blade but not pushing it against the bearing. This enables a cut that’s thinner than the kerf, which without the piece of wood supporting the blade would want to drift past the tenon.

Now you’re ready for your second rip, adjust the fence to suit your mortise chisel width using a vernier caliper to measure a trial cut. Then once you’ve established correct fence adjustment, rip all your tenons to their finished thickness.

This method will give near perfect tenons and is something I practice almost daily in my workplace.

You might be able to do this method without the piece of wood if the blade is new, but works best with the support in place.

 

[pe2dave]

Saw (hand or bandsaw) then finish with hand router?

 

[Sam Kilby]

I find a bandsaw to be up to the job for tenon cheeks only when a few criteria are met, firstly that it’s big enough for the job in hand (little bench top jobs aren’t really up to it in my experience)
Then that it is fully tuned up, and then that the blade is a very sharp wide low tip blade.
I would also recommend thicknessing blocks up that work for all your mortice chisels and your bandsawing setup. so you can always work off the same face to fence, and saving and labelling these to stay with the bandsaw.
All in all, if traditional tenon cheeks ought to be straight from the handsaw saw, with the right setup you ought to be able to get them out straight from the bandsaw..
obviously a spindle with a rebating or a tenoning block can be better, but arguably more setup time. And you ideally need a coping or tenoning sled, or a sensible push through board arrangement.
Same with a router table, except more passes and changing the setup a fair amount.
Shoulders on the table saw (presuming your riving knife setup will allow) or on a mitre or chop saw, radial arm saw, or handsaw and chisel back.
Either way I personally would still be marking all the components, with a marking knife and wheel gauge (again using mortice width blocks and a hole drilled through) or a mortice gauge.

 

[HOJ]

Do you get reliable straight cuts ? Can I ask, do you have the original blade guides ?

I have only changed the thrust bearing on mine which is the 401E model, to be honest it gets absolutely hammered in my shop as I use it in preference to my table saws, never had an issue with straight cutting, but I do change the blade quite regularly, as I use it to make quite a lot of curved cuts.

When I've only a few tenons to do, I like @Cabinetman set my bandsaw to cut both tenon cheeks, with the same stock face referencing of the fence, but do it differently, I have a stop set against the back of the fence where i place a gauge block for the tenon thickness offset i need, so move the fence, but it is controlled by the gauge block setting, I still cut the shoulders by hand.

I can use my SM to make them, as it has sliding carriage and I have tenon discs and a flush block, but I am fortunate, as when I have more than a few to do I'll set up my Sedgwick three head tenoning machine, that makes light work of them, as in this lot, plus another 20 more:

 

[aebersold]

Two methods:

1. Saw the shoulders on a tablesaw with a stop to enable the rail to be flipped. Then resaw blade on a bandsaw, using the fence for a guide. Obviously, test cuts are required.

2. Tenon saw. If needed, clean up with a rasp or router plane. If you want a fixture for hand sawing, make this one I designed years ago ...

http://www.inthewoodshop.com/ShopMadeTools/TenonGuide.html

Regards from Perth

Derek

Thanks for your post Derek. I like your sawing jig and it looks to give you nice results.

 

[aebersold]

I find a bandsaw to be up to the job for tenon cheeks only when a few criteria are met, firstly that it’s big enough for the job in hand (little bench top jobs aren’t really up to it in my experience)
Then that it is fully tuned up, and then that the blade is a very sharp wide low tip blade.
I would also recommend thicknessing blocks up that work for all your mortice chisels and your bandsawing setup. so you can always work off the same face to fence, and saving and labelling these to stay with the bandsaw.
All in all, if traditional tenon cheeks ought to be straight from the handsaw saw, with the right setup you ought to be able to get them out straight from the bandsaw..
obviously a spindle with a rebating or a tenoning block can be better, but arguably more setup time. And you ideally need a coping or tenoning sled, or a sensible push through board arrangement.
Same with a router table, except more passes and changing the setup a fair amount.
Shoulders on the table saw (presuming your riving knife setup will allow) or on a mitre or chop saw, radial arm saw, or handsaw and chisel back.
Either way I personally would still be marking all the components, with a marking knife and wheel gauge (again using mortice width blocks and a hole drilled through) or a

Thanks for your post Sam, lots in there and so many ways of skinning the cat !
I’ve looked harder at my set up and I think my blade could be sharper and on inspection my blade is only 1/2mm thick which probably causes the drift. I think I’ll invest in a more sturdy M42 3/4” 3tpi and try again on my next project. When I get my SM working again I’ll experiment with that too. My combination machine has a slider which should assist nicely. Alex

 

[aebersold]

Most joinery does not have centralised M&Ts. It's dominated by rebates, mouldings etc. Position of everything is from the best face/edge.

I’ve just understood your detail here, when I cut my central rebates where the doors meet and cut through the tenons. Doesn’t look great but it’s remaining ! With only 22mm of thickness it would be tricky to hide them. The only other way would be to make the tenons shorter. Thanks, Alex

 

[Jacob]

I’ve just understood your detail here, when I cut my central rebates where the doors meet and cut through the tenons. Doesn’t look great but it’s remaining ! With only 22mm of thickness it would be tricky to hide them. The only other way would be to make the tenons shorter. Thanks, Alex

Or to plant on the other bit which isn't a rebate (wossitcalled) so the stiles are all the same size. Add a bead and you can't see the join.