# How to actually use a drill press mortising attachment



## sprior (Aug 31, 2008)

I've had clone of a Delta mortising attachment for my benchtop drill press for over 10 years now and still haven't used it for a project because I never got comfortable setting up and using it. All the ones I've seen look pretty much the same but I attached a pic anyway.

Now that I'm gaining confidence in other aspects of woodworking I want to finally get comfortable with mortise and tenon joints.

While the attachment came with very basic instructions which I have followed to put the thing together, whenever I set it up to make some practice mortises they come out with jagged sides (which I know is the chisel rotated a little) and it seems like a super pain to adjust for drilling into the center of the edge of a board - doing so loosens everything so you're probably now out of square with the chisel again.

So I'm looking for a tutorial on the best practices for setting up and using a drill press mortising attachment including any jig pieces you build to make it easier to use. Can anyone provide some links or tips?


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## Gary Beasley (Jan 21, 2009)

I used a shim between the chisel and the back guide to set it square the best I could. You'll find that the mortise doesn't need to be perfectly smooth inside to work. A little roughness can help hold the glue. You just need to get the position good.


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## sprior (Aug 31, 2008)

I practiced a few mortise and tenon joints today by starting with a single piece of wood, cutting a mortise near the edge of one end and then cutting a tenon on the other and only when I was done with both cutting the board in half and putting them together. They actually came out pretty well with my biggest problem being a tighter fit than desired (it was very hard to get them apart after a dry fit). Using the same piece of wood this way meant that in a perfect world all the joints would have ended up completely flush and smooth - I came pretty close, but could always feel a hair misalignment which could probably sanded out. Just for fun I cut through the joints with the band saw afterward to do a post mortem on them.

The question that comes to mind is am I setting up too difficult a scenario in my practice - is it common to use mortise and tenon joints for joinery between two pieces which should end up perfectly flush or is there almost a reveal/shadow line/offset between the two pieces which would cause the kind of alignment I'm shooting for to be overkill (or am I just looking for excuses by asking this question)?


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## Gary0855 (Aug 3, 2010)

I have the same jig for my press, the first time I used it seemed difficult to set up, but like anything else, the more you do it the easier it becomes.
Tight is better than loose, you can clean up any unevenness with a chisel or take a little off the tenon. A bit harder to put it back on!!!

I have built a few tables were I M&T the rails(3/4") in the center of the legs(2"), but there is no reason why you can't have them flush if you wanted.

Just remember, Wood filler and 60 grit, you too can make things flush!
Gary


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## Gary Beasley (Jan 21, 2009)

This video may be some help in setting up the mortiser.
http://www.youtube.com/profile?user=InTheWorkshop#p/u/6/73oxhyQzR2E
It's with a dedicated mortiser but the setup is going to be similar and adaptable to the attachment.


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## LKW (Aug 15, 2010)

I have one of the Delta mortising attachments and I prefer to use the Beadlock Pro Jointery Kit from Rockler.com at this link. It works great and is a little more forgiving than mortise and tenon.


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