Thread: Mortising Jig

Originally Posted by jchappo

Paul, both the jig and the table look great, but which section in Bunnings did you get the tri-knobs?

John

Hi John,

The knobs are just in the builders hardware area. I think most stores are arranged the same, so it's near the other fasteners etc. I'll go for a walk at lunch and check which isle number at the local store.

Paul.

John,

The parts are in aisle 4 at the Bunnings store in Wollongong. Builders hardware. The brand is Cornall. They live in the same area as the rubber stoppers that go on chair legs etc. The T-nuts are in the same area.

I'm guessing that Bunnings lay out all their stores in a similar fashion, so hopefully you'll find them.


In regard to the use of the jig. I don't have a tail vice like Rocker, so had the jig in the front vice. I stand to the left of the jig (workpiece window on the right as I'm looking at it) and plunge the router at a stop closest to me moving the router away from me. In this way the fence is on the left as I'm working. This method (fence on the left) is from an instructional poster that I got from a Les Miller demo at the Timber show awhile back.

Regarding rounding tenons vs squaring motices. For the change table I built, I cut square tenons and then chiselled each corner making a half hexagon like this

/-\
| |

This allowed the tenon to fit neatly in the mortice, and allowed some space for glue squeeze out. This took all of three seconds per corner. About 20 seconds per tenon. Much quicker and easier than the other two options. I think Rocker actually suggested this idea to me in the first place, so I can't claim credit for it.

Hope this helps.

Paul.

I have modified Rockers morticing jig for my workshop and thought I might share some of the ideas with the forum.

Firstly I have the workpiece flat on the workbench (I use a 20mm thick MDF board so that it is a level surface) raher than clamping in mid air. The jig itself is in 2 parts, the top can slide back and forth so that the 'zero' position for the router bit is in the middle of the stock. The bottom part of the jig has a side support I can use to clamp to if required and also a 150mm square cut out so that long stock can poke through. I used 4mm aluminium plate for the stops and 10mm wide 4mm thick aluminum strip to keep the stops parallel and perpendicular to the front edge. At the moment I have not added rulers to the top but intend to when I can find a high contrast stainless steel version.

In use I have not yet had to clamp the workpiece as the weight of the jig and the vice clamping has sufficed, however, if needed I will add a same sized piece of stock under the back right corner and use a deep throated clamp to hold it in place. It doesn't have the micro adjuster of Rocker's original but so far I haven't needed it plus I would have to adjust both font ann back stops to keep the mortice centered in the stock. I made a couple of brass faced 'setup' blocks that are put in the opening so that the centre lines on the top of the jig line up with centre lines on the stock.

There are hardwood runners on both sides of the jig to ensure that the top moves perpendicularly to front edge. I probably not explained myself very well but hopefully the pictures will make up for it.

Image 1 full jig view from front
Image 2 full jig view from left side
Image 3 base from back
Image 4 sliding top of jig
Image 5 'setup' blocks

Regards

Mike

P.S. Before I get flamed for this I have already checked with Rocker and he is happy for me to add this!

Can anyone tell me why don't the attachments stay in the same order as shown in the Manage attachments window ?

Mike

MTP

I myself always upload my pictures these days to a host (photobucket) and then post pictures full size.

You have not yet stated that the mortices were 100% successful

So far yes 100%

Mike,

Your jig certainly looks a bit easier than mine to build, but, in its present stage of development, you would not be able to obtain the same precision with it, since it lacks scales, a dial gauge, and micro-adjustment.

I considered using your method of guiding the stop blocks, but was dubious whether it would be feasible, if using MDF for the platform, to attach the guide bars firmly enough to ensure that there would be no play between them and the stop blocks.

By the way, it is not necessary to have fences on both sides of the router to guide it. So long as you feed the router in the correct direction, the bit rotation will hold the router firmly against a single fence, as in my jig.

Rocker

Rocker,
The two stops one on either side is so that I can set the width of the mortice before I start cutting.

Regards

Mike

Originally Posted by MikeThePom

Rocker,
The two stops one on either side is so that I can set the width of the mortice before I start cutting.


Mike

Mike,

I normally just use standard widths, corresponding to the available diameters of spiral bits, for my mortices. In the rare instances where I need a mortice thicker than 1/2", I use a spacer. So, if I want to cut a 7/8" thick mortice, I make one pass with a 1/2" bit; then I put a 3/8" spacer against the fence, and make a second pass, this time feeding the router in the opposite direction to the first pass. In this way, a second fence is not needed.

Rocker

Rocker

Jow, check your PMs.

Rocker

Originally Posted by Rocker

Jow, check your PMs.

Rocker

OK Rocker, message received.(@ 8 am BST)

(my internet service is restricted and finishes at 4pm BST each day)

Both you guys have nice jigs.

I have only made a few things where I used tenons and motise. I would love to use some more in future prodjects. I would like to build a jig that has the abliity to repete a mortise and tenon that I might of made last week with out a lot of set up again. I owen an Incra TS fence and relay on the fact that I can recut another peice after messing up one with out having to get a tape out and meausing anything.

Rockers jig has a dial for acurey but I was wonderin if there would be a way to make a drop in Block or template for quick set up for you most commenly use seting ( lets say 1/2 or 3/4" stock for me )

Mikes Jig looks like it would be easy to make a drop in template for seting it up fast. It just looks like it would need a way to refind the center, even with a template in use. Just say SWHBO uses one of your cut peices as a planting stack or the Dog thinks it is a bone.

Would eather of your jigs be able to cut a fourth table skirt with the first 3 allready glued in place so you cant use them for a guide, to make it harder you have allready taken your Jig off the vice or table, reset it to "0" position or a storage position.

Remember I use to be in the mititary and we used hammers and rocket launchers with the instruction printed on the side of them.

I have seen the Leigh Ind. Mortise & tenon jig in use at a wood show and watch the guy make two joint. the secound one did not work because he goffed and just shureged if off. I know the Trend has one too but have not see one in use. Somthing like the trend with drop in templates is what I would like to build.

Junkboy,

It is easy to calibrate my jig so that you can read the distance that the mortise is from the face of the workpiece directly from the dial gauge. If you want an article on my jig, PM me your e-mail address. I even have a Murcan version in inches, cubits, etc.

Rocker

Junkboy, I thouroughly recommend Rockers version in bees dicks. The hard part is convincing that many bees they don't need them anymore!