Making Mortises

[Joe Von Kaenel]

Hello,



One of my goals is to learn to make Mortise and Tendon joints in 2009. I have a Delta attachment for my drill press but it is difficult to make good mortises. What is the trick to getting good mortises with the drill press attachment? I have a plunge router, would I be better off getting a "Mortise Pal" or a bench top mortising machine. Woodworking is just a hobby. I've just struggled with this type of joint for a long time and ended up using something else, like pocket screws etc. Thanks


Joe

[Lee Schierer]

I have a drill press morticer and make mortices with it all the time. You need to hone the outside of your chisels to insure they are super smooth (yes they get slightly smaller). Not they don't come that way out of the box. You may also need to shapren the inside. Then set up your morticer so that the drill bit is about 1/32" to 1/16" lower than just touching the inside of the chisel. Align your chisel with the fence (if you don't have a fence you need to make one). Run the chisel at about 1400-2000 rpm. Place the wood under the chisel and apply downward pressure. It will take more pressure than straight drilling to do this since you are pushing the chisel into the wood at the four corners. Once you are at depth hold down the piece of wood and raise the chisel. (this is where the smooth exterior of the chisel comes into play). If you are making a long slot, move the wood at least 3/4 of the width of the bit and make the next cut. I usually do both ends and then remove the material in between on long slots.

http://sawmillcreek.org/attachment.php?attachmentid=105548&stc=1&thumb=1&d=1231008695

[Greg Hines, MD]

I use a jig for mortising. It is made of a baseplate for my plunge router, made of 1/4" hardboard, and a pair of fences mounted with T-bolts through slots on either end. This allows you to sandwich your board, and plunge in to make your mortise. For the few mortises that I make, it works just fine for me. If you intend to mass produce projects, then a dedicated mortising machine would be a good choice.

Doc

[Kirk Poore]

A tenoning jig for the tablesaw is really nice too. You'll get consistent-thickness straight tenons that way without lots of tweaking. I can hand-chop pretty decent mortises, but getting the tenons right by hand was always harder.

Kirk

[Neal Clayton]

a benchtop mortiser would be a minimal improvement over the drill press jig. any vertical mortiser without a horizontal clamp is inherently limited.

router jigs can work very well, from my experience, although are not feasible for doors, windows, etc. in which the tenon will be hidden behind cope joints.

if you're thinking about buying a mortiser, skip the benchtop models. same principle as a benchtop table saw or benchtop jointer. they're easily out-grown.

[Rod Sheridan]

[quote=Neal Clayton;1011507]a benchtop mortiser would be a minimal improvement over the drill press jig. any vertical mortiser without a horizontal clamp is inherently limited.

quote]

I'd disagree with the statement that a bench top mortiser is a minimal improvement for the following reasons;

I've owned a General International bench top mortiser for 8 years, and have made aproximately 1,000 mortices with it. The GI has the following attributes

- a good fence that stays parallel to the chisel face as you slide it back and forth to position the mortise

- a good horizontal clamp to hold the work tightly against the fence

- a long lever arm to provide sufficient force to make large mortices in dense wood

- a good hold down clamp

- easily adjusted depth stops with nitrogen struts to balance the weight of the head

- heavy cast iron column with dove tailed ways and adjustable brass wear strips for accuracy and long life

In addition you won't have to spend time converting your drill press into a mortiser every time you want to use it.

Regards, Rod.

[Jim Kountz]

[quote=Neal Clayton;1011507]a benchtop mortiser would be a minimal improvement over the drill press jig. any vertical mortiser without a horizontal clamp is inherently limited.

quote]

I'd disagree with the statement that a bench top mortiser is a minimal improvement for the following reasons;

I've owned a General International bench top mortiser for 8 years, and have made aproximately 1,000 mortices with it. The GI has the following attributes

- a good fence that stays parallel to the chisel face as you slide it back and forth to position the mortise

- a good horizontal clamp to hold the work tightly against the fence

- a long lever arm to provide sufficient force to make large mortices in dense wood

- a good hold down clamp

- easily adjusted depth stops with nitrogen struts to balance the weight of the head

- heavy cast iron column with dove tailed ways and adjustable brass wear strips for accuracy and long life

In addition you won't have to spend time converting your drill press into a mortiser every time you want to use it.

Regards, Rod.

I agree, a dedicated mortiser as Norm calls it, is a vast improvement over a drill press attachment. The biggest key is to hone those darn chisels, you will never get it right without doing that first. Second is setup and third is making sure the work is secure.

[pat warner]

Tho it has its limitations making joints, the router does well morticing (http://patwarner.com/router_morticing.html).

[Joe Petersen]

I like the router mortise as well but I prefer loose tenons. Cut two matching mortises keeping the same face to the fence guarantees alignment. I cut square stock for the tenon and round the edges with a chisel or box cutter.

[Roger Warford]

I've just struggled with this type of joint for a long time and ended up using something else

What sort of problems have you had? I'm pretty new at this, but I'm getting reasonable (though not great) joints. The mortise doesn't seem to be a problem for me. I use a drill press (sans mortising attachment) and chisel. The chiseling is far easier than I had imagined before I tried it. I seem to be more challenged with tenons.

[Peter Quinn]

I have a drill press morticer and make mortices with it all the time. You need to hone the outside of your chisels to insure they are super smooth (yes they get slightly smaller). Not they don't come that way out of the box. You may also need to shapren the inside. Then set up your morticer so that the drill bit is about 1/32" to 1/16" lower than just touching the inside of the chisel. Align your chisel with the fence (if you don't have a fence you need to make one). Run the chisel at about 1400-2000 rpm. Place the wood under the chisel and apply downward pressure. It will take more pressure than straight drilling to do this since you are pushing the chisel into the wood at the four corners. Once you are at depth hold down the piece of wood and raise the chisel. (this is where the smooth exterior of the chisel comes into play). If you are making a long slot, move the wood at least 3/4 of the width of the bit and make the next cut. I usually do both ends and then remove the material in between on long slots.



Beautiful explanation. I might add that making a simple table with a stout adjustable fence and some accommodation for a quick clamp or two with t tracks is a big aid. Check rockler and woodpeck.com for ideas for drill press tables. They sell them though you could make one fairly cheap. It will alos make your drill press more useful in its own right.

I have a delta drill press with a morticing attachment and have never had a problem with it for up to 1/2" mortices. Sharp chisels and bits (few come this way) are necessary for any chisel morticer to work well, even a big floor model. Check rockler or similar for a kit to sharpen the chisels and bits, maybe even amazon? At work we have a floor model that while more convenient given its rack and pinion table and clamping mechanism is no more accurate than my drill press. I have never tried very deep mortices or anything over 1/2" on the drill press.

[Jerry Olexa]

The main advantage of a dedicated mortiser IMHO is the leverage gained by the long handle. Much easier to use and get your mortises easily. Sharpness also an issue...Now I usually use a plunge router with a jig.

[Scott Vigder]

I build Mission Style furniture, so virtually all my joints on larger pieces are M/T joints.

I use a General bench top machine, and I am constantly amazed at how well it performs repeated tasks.

As you can see from this pic, some of my projects require a LOT of mortises!

http://www.sawmillcreek.org/attachment.php?attachmentid=35195&d=1143645564

[Joe Chritz]

I'm in the plunge router and jig whenever possible group.

Basically a baseplate and some sides the router just fits into. A stop on both ends limits the travel.

One end is fixed the other is adjustable, granted it is with a piece of plywood screwed in place but it is adjustable. I use plywood screwed to the underside to position it on the stock being used. I have to reset those for each project but once set multiple mortises are very fast.

I am putting together two bed tables and there are 12 moritses 1/4 x 8 1/4 and it took about an hour to do all of them, including two that are 1 1/2 long.

I need some work on getting the tenon's just right but I generally leave them a fuzz fat and tune to fit each mortise.

Joe

[Neal Clayton]

[quote=Neal Clayton;1011507]a benchtop mortiser would be a minimal improvement over the drill press jig. any vertical mortiser without a horizontal clamp is inherently limited.

quote]

I'd disagree with the statement that a bench top mortiser is a minimal improvement for the following reasons;

I've owned a General International bench top mortiser for 8 years, and have made aproximately 1,000 mortices with it. The GI has the following attributes

- a good fence that stays parallel to the chisel face as you slide it back and forth to position the mortise

- a good horizontal clamp to hold the work tightly against the fence

- a long lever arm to provide sufficient force to make large mortices in dense wood

- a good hold down clamp

- easily adjusted depth stops with nitrogen struts to balance the weight of the head

- heavy cast iron column with dove tailed ways and adjustable brass wear strips for accuracy and long life

In addition you won't have to spend time converting your drill press into a mortiser every time you want to use it.

Regards, Rod.

the general benchtop model is a different breed for the simple fact that it does have a horizontal clamp. if we were talking table saws, the rest would be contractor saws and the general would be a hybrid ;).

every other benchtop model, since powermatic discontinued the 719, does not.

and without a horizontal clamp a mortiser is shaky, at best, imo.

[Mike Heidrick]

The PM 719 was/is a floor machine correct?

[Neal Clayton]

the old 719 was a non tilt benchtop that had everything but the sliding table, just like the general.

it was discontinued and replaced by the 719T, which is a floor standing model that tilts as well.

[Don Dorn]

I use the router - used to use the Tage Frid type jig and it worked, but it required allot of clamping for a few seconds of mortising. I splurged and bought a Mortise Pal and love it. Yep, it was spendy, but mortises are now a snap, and very quick to do.

I have a metric template for it that allows me to use Festool Domino biscuits for loose tenons, but if I want solid tenons, I just flip the jig around and do a finishing pass on the other side which gives me a perfectly centered mortise.