Square holes with drill press?

[David Tolsky]

Forgive this newbie question. I'm looking to make square holes or possibly rectangular cut outs using my drill press. Are there bits available similar to mortising bits but useable with the drill press? Thanks for your help.

[Frederick Skelly]

There are mortising attachments for your drill press. I've read mixed reviews - some good and others not. Google "mortising attachment for drill press" to see some options and prices.
Fred

[Jay Michaels]

Mortising attachments are available for drill presses, as Frederick mentions, but they'll make you want to lose your mind.

For a one-off project or few mortices, you might be able to handle the frustration that will ensue, but I make no promises.

I bought one early in my woodworking career and used it on one project (to mortise rectangular slots in the rails of a wagon to receive the removable sides) and it did the job (barely), but was frustrating to use and produced a less-than-stellar cut.

[Richard Coers]

Don't buy the attachment if you are working in hard maple or white oak. You'll be better off drilling a row of holes with a Forstner bit and pare the waste out with a chisel. Just not enough leverage on a drill press to shove in a chisel in hard wood.

[Doug Dawson]

Mortising attachments are available for drill presses, as Frederick mentions, but they'll make you want to lose your mind.

For a one-off project or few mortices, you might be able to handle the frustration that will ensue, but I make no promises.

Yeah. It'd be easier and more efficient to just use a plunge router (with a jig that you could make.)

Or maybe you could ask for a Festool Domino for Christmas. It's not too late. :^)

[Thomas Wilson]

I have used a Delta mortising attachment on a drill press for many types of wood. My attachment is pretty old, maybe 35 years. I never had a problem with the wood. I did have some problem with sharpening the chisels. I did figure out some creative ways to sharpen the chisels with a Dremell tool and small cylindrical grind stone.

On any mortising chisel and bit combination, you need to allow clearance between the bit and chisel. Otherwise it will get hot, turn blue, and lose its temper which pretty much ruins the bit.

[David Tolsky]

What I want to be able to do is cut a deep rectangular flat bottom "box" as a compartment to put things into. What about a straight bit in a plunge router with a template of some kind to cut a clean rectangle?

[Jim Becker]

What I want to be able to do is cut a deep rectangular flat bottom "box" as a compartment to put things into. What about a straight bit in a plunge router with a template of some kind to cut a clean rectangle?

Template routing is a very common way to create pockets for box-making...pretty much easy to do. The corners will not be "square" when the router is done, but if you require that, you can pair the corners manually with a really sharp chisel. The router, in the mean time, has done all the hard work and you're only left with cleaning up the mess with your shop vac and broom. :)

[Brian Tymchak]

What I want to be able to do is cut a deep rectangular flat bottom "box" as a compartment to put things into. What about a straight bit in a plunge router with a template of some kind to cut a clean rectangle?

Not knowing more about your application, there are bandsaw box techniques that might be helpful. Basically you slab off the sides and top and bottom leaving the middle. Throw the middle away and glue the sides and bottom back together and you have a box with a top.

[Lee Schierer]

I have a drill press mounted mortising attachment and I use it for all my mortises. For a non-production shop it works very well. The chisels as they come out of the box are rough on the exterior so they go in pretty easy, but are very hard to pull back out. I honed the outside surface of all my chisels so they have almost a mirror finish and they go in and pull out much easier. The down side of using a mortising set up for what you want to do is the drill bit sticks out the bottom of the chisel and leaves a circular mark with a center hole in the bottom of your mortise. Attempting to clean these marks out from your box recess would be very time consuming and difficult.

[Bill Dufour]

In metal a rotary broach is depth limited to about 1.5 times the diameter. The common available size the max size is about 1/2 inch square.
Bil lD

[Jacob Reverb]

Depending on the dimensions of this hollow "box," I'd probably try to use the drill press with forstner bit (using the stop nut on drill press to keep depth consistent), then chop/pare to size with sharp chisels.

[Ole Anderson]

I have the Delta mortising attachment for my Craftsman DP. It took a few mods to make it work. I was able to make multiple 5/8" square holes in QSWO. Is it as easy to use as a dedicated mortiser? Of course not, but it worked and I don't have one more infrequently used tool taking up space in my small shop. There are probably better techniques for your project.

[David Tolsky]

I have the Delta mortising attachment for my Craftsman DP. It took a few mods to make it work. I was able to make multiple 5/8" square holes in QSWO. Is it as easy to use as a dedicated mortiser? Of course not, but it worked and I don't have one more infrequently used tool taking up space in my small shop. There are probably better techniques for your project.

Ole, your first two pictures, that's exactly the type of slots I want to make but on a bit larger scale. They will not be mortises but rather "compartments" for one to insert a tool or other item. I'd want to cut deeper and make the slots twice the width of your first picture.

[michael langman]

Something to be aware of with the drill press mortising attachment is you really need a drill press with 5-6 inches of travel to do deep mortises. You lose some depth of cut as the attachment takes up space on the quill. The 3 1/2" of travel of my drill press quill limits me to shallow mortises. A drill press with 6" travel is ideal.

[Bruce Page]

An unconventional method that makes beautifully square holes is broaching. You drill a pilot hole then using the DP as an arbor press, push the broach through. I picked up this broach and a couple of others off of eBay for very little money.

[Bill Dufour]

Broaches can also be made from hex keys. These are hardened steel and when sharp they can broach steel as well as wood.

[Ole Anderson]

Something to be aware of with the drill press mortising attachment is you really need a drill press with 5-6 inches of travel to do deep mortises. You lose some depth of cut as the attachment takes up space on the quill. The 3 1/2" of travel of my drill press quill limits me to shallow mortises. A drill press with 6" travel is ideal. As long as your drill press table or head can be lowered or raised, I don’t see how this would be a problem.

[Robert Hazelwood]

An unconventional method that makes beautifully square holes is broaching. You drill a pilot hole then using the DP as an arbor press, push the broach through. I picked up this broach and a couple of others off of eBay for very little money.

Interesting. I have been trying to make square holes for square pins using a pilot hole and a hollow chisel, hammered by hand. Sort of works but I'd like a better method, and for now do not want to purchase a HCM.

These push broaches look like they'd cut very well, but seem to be pretty expensive. I have a couple of concerns- one is the length. Seems like you have to push it all the way through and they are at least 8" long. Most drill presses don't have that much travel, mine certainly doesn't. Do you take partial cuts and then keep raising the workpiece with spacers, or put spacers between the chuck and the tool? If so do you have any problems with keeping the tool aligned? Using a hollow chisel as a punch, one of the biggest problems is that the tool tends to rotate as it goes through.

The other issue is with spelching on the backside of the cut. With the hollow chisel I can work from both sides, but that doesn't seem very feasible with the broach. How bad is the spelching if you use a tight backer board?

[Stan Calow]

Corner chisels like these from Lie-Nielsen https://www.lie-nielsen.com/nodes/4175/corner-chisels are what I use. Much easier to register them on two sides.

[Bruce Page]

Interesting. I have been trying to make square holes for square pins using a pilot hole and a hollow chisel, hammered by hand. Sort of works but I'd like a better method, and for now do not want to purchase a HCM.

These push broaches look like they'd cut very well, but seem to be pretty expensive. I have a couple of concerns- one is the length. Seems like you have to push it all the way through and they are at least 8" long. Most drill presses don't have that much travel, mine certainly doesn't. Do you take partial cuts and then keep raising the workpiece with spacers, or put spacers between the chuck and the tool? If so do you have any problems with keeping the tool aligned? Using a hollow chisel as a punch, one of the biggest problems is that the tool tends to rotate as it goes through.

The other issue is with spelching on the backside of the cut. With the hollow chisel I can work from both sides, but that doesn't seem very feasible with the broach. How bad is the spelching if you use a tight backer board?

Robert, you do have to push the broach all the way through. I raised the table as I went. Once you have the broach started into the work piece an inch or two it becomes self-aligned so positioning or alignment of the table/broach/DP chuck is less important. I used a piece of ¼” MDF as a backer. As you can see from the pic, I didn’t have any blowout in the 1” thick QSWO.
After posting yesterday I checked out eBay to see what’s available. It’s been several years but IIRC, I paid ~ $100 for the 3 broches I have – much less than what I saw listed yesterday.

[Donald Hofmann]

I got the Delta mortising attachment for free with my Delta drill press. Even with sharpened chisels it was too hard to use. I then bought the Jet mortiser. I had to attach an extension to the handle to make it easier to use. I sold it and made a floating tenon jig for my router

[Derek Cohen]

Forgive this newbie question. I'm looking to make square holes or possibly rectangular cut outs using my drill press. Are there bits available similar to mortising bits but useable with the drill press? Thanks for your help.

David, I know that this is not what you asked, but I long ago rejected the drill press for morticing (as it is so inefficient and clumsy, and leaves a coarse finish), and instead use a router. I have a fixture that does this very easily, very accurately, and then (if you prefer, as I do) square up the ends with a chisel. Yell out if you are interested in this, and I will post pictures.

Regards from Vienna (currently)

Derek

[David Tolsky]

An unconventional method that makes beautifully square holes is broaching. You drill a pilot hole then using the DP as an arbor press, push the broach through. I picked up this broach and a couple of others off of eBay for very little money.

Nice! that's really cool.

[David Tolsky]

David, I know that this is not what you asked, but I long ago rejected the drill press for morticing (as it is so inefficient and clumsy, and leaves a coarse finish), and instead use a router. I have a fixture that does this very easily, very accurately, and then (if you prefer, as I do) square up the ends with a chisel. Yell out if you are interested in this, and I will post pictures.



Regards from Vienna (currently)

Derek

Yes I'd love to see pictures. I wouldn't even begin to know how to create a template for router plunging a square hole. I'm of course willing to square the holes up with a chisel.

[Derek Cohen]

Yes I'd love to see pictures. I wouldn't even begin to know how to create a template for router plunging a square hole. I'm of course willing to square the holes up with a chisel.

The fixture holds the router and clamps a board to it ...

https://i.postimg.cc/5NLS6KHj/1a.jpg

https://i.postimg.cc/TPYVNRtW/2a.jpg

boards clamped ...

https://i.postimg.cc/pdGDggSc/3a.jpg

Router set up ..

https://i.postimg.cc/431Yf9fX/21a.jpg

https://i.postimg.cc/268VVSyh/22a.jpg

Regards from Perth ... Vienna at present

Derek