Mortise & tenons Cutting accurately

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aebersold

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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
 
@Spectric 😂😂
Your absolutely right, but you can make one either using the slot or by attaching a false base create a reference for a slide. A top hat spindle coupled with a rebate block enables any size tenon to be cut. Alternatively Whitehill make tenon blocks which can be stacked to cut a tenon in one pass.
 
Bandsaw never as precise as you'd like.
Cut all mortices first and tenons next, before rebates, mouldings etc.
For tenons, first is to have them marked, face, edge, and mortice gauge mark for the cheeks, all round. Properly marked with gauge aways set to either face or edge, and marks for haunches, though you can get away without the latter.
Then with very sharp blade set the fence by trial and error so that the line of the cheek underneath cuts spot on plus a gnats, with the face mark against the fence. Then as you cut keep the workpiece pressed uptight to fence and watch the blade as it cuts into the top and adjust if necessary, while the bottom of the cut takes care of itself.
When you've done them all set the fence to cut the haunch lengthways and when all done set it to cross cut out the waste.
A coarser big blade with a bit of set is likely to cut straighter than a fine narrow one.
Then the shoulders last, over a TS or under a chop saw better.
 
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Thanks all, that’s helpful. @deema the spindle sounds faster and more accurate. When my spindle is up and running, I’ll give that a go and try to make a tenoning machine using the spindle. I’ve watched Oliver on Bradshaw joinery who makes it look so easy and they fit nicely straight off the machine, but I’ve a way to go before I achieve that. @Jacob thanks for the detail. Marking them all up is such a faff. I wanted to marked one up accurately, set the bandsaw up and run them all through which I did, but the cuts were not consistent which was frustrating. I was mindful to make sure the cuts were proud. The blade is a coarse rip with wideish set but I think it could be sharper. Don’t mind the bench work but it takes forever !
 
You can set the fence to cut the first tenon, but between the door rail and the fence you put a special piece of wood that’s the exact size of the mortice plus? One kerf of the b/saw.
Then all you need to do is remove the piece of wood and it will automatically set it up to cut the next side of the tenon.
It’s a while since I prepared all my special bits and I might have got the kerf bit wrong, but you will soon see when you try it.
Ian
 
I use my Startrite bandsaw regularly to cut tenons on the fly, it only ever has a 3/4" x 3 tooth per inch skip blade in it, I would suggest from what you have said, your blade may be well due for a change, have you cut any curved pieces with it?

I’ve watched Oliver on Bradshaw joinery who makes it look so easy and they fit nicely straight off the machine,
I think you will find he's using a Sedgwick 3 head tenoner though, completely different set up to a spindle moulder.
 
.... Marking them all up is such a faff. ....
Not as big a faff as correcting the mistakes. I'm into 100% mark up as a matter of course, unless your kit can really be set precisely and predictably. Also it saves on simply getting things wrong. I used to do a lot of sash windows which could mean 100s of components, all marked up from a rod and hence easy to identify and every cut checked against the marks
 
Americans (and myself before a multico) use a dado and a mitre fence on the table saw. I still do some aspects this way occasionally. It works and isn't to slow. If your using a morticer watch as your mortices may be slightly off centre (morticer uses a single datum fence) have set up waste the same size and marked faces.as the dado references of 2 faces resulting in problems.
 
It's better to centralise your mortices if using this method and focusing on straight square timber that's equal thickness/width. So either work from both faces with mortice and tenon(or groove and stub tenon by turning between cuts) or work mortice and tenon from one face only(morticer and tenoner) one obviously restricts the joint to the centre.
 
@Cabinetman That’s a useful tip Ian thanks and means you can reference off the same face too.
@HOJ I think you may be right. My blade has a couple more teeth per in, I haven’t cut curves with it but I have put some serious lumps of iroko through it, so yes it’s probably up for replacement. Do you get reliable straight cuts ? Can I ask, do you have the original blade guides ?
@Jacob Ha, maybe I should stop being so lazy, it would certainly help in trimming the cheeks, having lines to work to. The end result will be fine, but think I’ve made it hard for myself. Thanks for your advice.
@johnnyb I managed to centre my mortises as I needed to flip them over to achieve a depth of 106mm with a 6mm chisel. I like the idea of a spacer thickness of mortise for the tenon. I’ve avoided the table saw method as it’s a bit on the risky side and working upside down ! I used to use a wadkin radial arm with a wide adjustable groover. The guard wasn’t big enough for the cutter. It was messy and victorian dangerous. It’s gone now ! Thanks
 
[.....
@Jacob Ha, maybe I should stop being so lazy, it would certainly help in trimming the cheeks, having lines to work to. The end result will be fine, but think I’ve made it hard for myself. Thanks for your advice.
I could spend several days sorting out the rod and marking up. After that on auto pilot and hoping that the pile of components would all come out as intended! No major failures, some occasional minor inaccuracies but easy fixes.
 
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.
 
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.
TBH I've never used a chop saw. Can you cut tenon cheeks with one?
 
It's better to centralise your mortices if using this method and focusing on straight square timber that's equal thickness/width. So either work from both faces with mortice and tenon(or groove and stub tenon by turning between cuts) or work mortice and tenon from one face only(morticer and tenoner) one obviously restricts the joint to the centre.
Most joinery does not have centralised M&Ts. It's dominated by rebates, mouldings etc. Position of everything is from the best face/edge.
 
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
 
It was always an issue as a garage woodworker. I always felt those methods ie single blade width move across again very slow and a bit dangerous as they are so repetitive and slow. Derek's router plane suggestion is a good one as longer tenons need to be parallel to work.
And router planes work consistently and well but slowly. Four inch chiseled mortices are much harder than four inch tenons imho so check those carefully as well.
 

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