Trend Mortise and Tenon Jig

[bluenose]

Do any of you fellow members use the Trend Mortise and Tenon Jig?

I am using mine at the moment and have run into a bit of a problem that I can't seem to find the answer to.

I experimented with some scrap timber and produced an excellent joint at the first attempt. My immediate thoughts were that this was going to be a doddle. Not so I'm afraid.

The first job that I did was a straightforward joint (90 degrees) which as I say, came out absolutely fine. However, the actual job that I am doing involves joints whereby the timbers being used have been cut at 22.5 degrees (my earlier thread 'help with angles' refers). I have set everything up exactly the same way as with my successful experiment but, upon completion, whilst the joints are a good fit, the timbers do not match up at all. they are about 5mm or so out.

Does anyone have any idea what I might be doing wrong please? Many thanks.

 

[Racers]

Out in which way?

Pete

 

[bluenose]

Hiya pete, thank s for coming in on my query.

I have placed each of the workpieces into the jig in an identical manner and, my understanding is that after cutting the first piece, whether that be the mortise or the tenon, all you need to do is then change whichever guide bush that you have been using. For the job/size that I am doing, the cutter is the same for both jobs.
Hopefully I have managed to attach a photo of the piece for you to see where the discrepancy is, as I say it is about 5mm.

 

[Racers]

How it each piece registered to the jig? do you use the inside corner on each piece or inside and outside? that could be your problem.

Pete

 

[bluenose]

As far as I can see you can only put any piece of work into the jig one way. The front face of the jig is adjusted/positioned at 22.5 degrees so that the part of the timber to be machined is flat. It isn't possible to set it up as 'opposites'

Below is a link to the jig being used.

https://www.youtube.com/watch?v=OT3i6CNEjUo

 

[Racers]

O/k then the problem is you are setting the tenon piece in wrong, it gets cut at an angle so the position of the tenon moves sideways as you cut deeper into the wood.
You need to draw the layout of the tenon to find where the shoulder is on the end of the piece.

Pete

 

[RogerS]

....
You need to draw the layout of the tenon to find where the shoulder is on the end of the piece.

Pete

I know that many will use pen and paper to do this but I've found that, having learned a little SketchUp, it's brilliant for this sort of thing. I was making a door using traditional mortice and tenons and the rails had double tenons with a haunch. The door was also rebated to have some panels dropped in.

Drew up the rails with the tenons and haunches then introduced that to the rebated stile. Interface with Selection and Bob's Your Uncle, the required mortice details are all there on the stile.