Thread: Using the Leigh FMT to make mortises and tenons.

Similarly to you I purchased one second hand as well as a second hand df500. I have found they both have their applications. Especially for table rails to leg joinery I like the FMT. I need to make a horizontal router I think....

Hi Hurcorh.

Yes, they do complement each other to some extent. I too, have found that the FMT is great for angled tenons that you need in chairs. But at times I like the clean crispness of actual tenons rather than floating tenons. The flexibility of joint size appeals greatly too. I'm just old school I think. Speaking of which.....

Adjusting the jig to give good fit of tenon into mortise.

If you look at the sole plate that you have placed onto the router, you will find a small adjustable hand screw at each end. (see pics) By adjusting these screws very gently and slowly, you will find that the mortise and tenon will change by very small margins to ultimately give a perfect size which will give a tight or loose joint. or somewhere in between. So you run a piece of scrap through the process, see how the joint looks and adjust the screws up or down a very small amount up or down. When you get a joint that is tight, but with room for glue, then you are there.

Another issue can be ending up with a face on the tenon face which is cut on an angle. if this is the case, then check how tight you have the clamps which hold the stick tightly in place.IMG_0360.jpgIMG_0361.jpgIMG_0362.jpgIMG_0363.jpgIMG_0364.jpgIMG_0365.jpgIMG_0366.jpgIMG_0367.jpgIMG_0368.jpgIMG_0369.jpgIMG_0370.jpgIMG_0371.jpgIMG_0372.jpgIMG_0373.jpgIMG_0374.jpgIMG_0377.jpgIMG_0378.jpgIMG_0379.jpgIMG_0380.jpgIMG_0381.jpgIMG_0382.jpg

Thanks Rob,I also have one of these FMT jigs I feel they compliment the work especially the angled applications.

Now if I can only sort out the angle in my neck I should be Jake!

It's been a few weeks since I posted on this thread and I feel that I should complete the method for using the Leigh FMT.

Once you have the tenon cut, you will need to make the mortise. This is easily done by digging a hole in the horizontal rail.

The process is the same as for the tenon except that,

1. You mark the centre of the place you want to put the mortise and ensure you have the template to match the tenon size. The soleplate of the router is set so that the guide pin for the router is installed into the middle of the template. Then the router can be plunged several times to gouge out the mortise. You can do this best by plunging several times, until you reach the end of the template, then climb back to smooth the mortise sides.

2. This is where you find out if you set the guide pins in the right place. I can't stress how important it is to set the jig up correctly. You can happily cut mortises all along a strip of wood, to match where you may, for example put the rails for drawers to sit on in a chest of drawers. This will also allow you to use a piece of timber as the corner of a box or chest.

3. The straight forward method means that it's hard to make a mess of the joints. If you have done the preparation correctly, you can sail through making the joints and glue them successfully togetherIMG_0361.jpg This shot of the jig shows clearly where the back guide pin sits in a long grooved piece of plastic. At the far end of the picture, you can see the guide for a particular size mortise and tenon pair.You make the tenon by routing around the guide and the mortise by routing inside the guide. IMG_0377.jpgThis is how a mortise looks on a rail.

Here is a picture of a small table made using this Mortise and tenon method. The time it took to make the table was approximately 3 hours. (Cutting the timber to size, setting up the M&T jig and then gluing up).
Here is the table assembled. IMG_0395.jpg
IMG_0404.jpg





Sorry that it's upside down, but I think you can see that you get a nice result by using a bit of patience.



Regards.

Rob