Delta 17-924 Mortising Attachment.....Will it fit???

[Butch Butler]

Does anyone on this forum know if the aforementioned mortising attachment is "dedicated" to Delta drill presses, or will it fit any drill press with a specific quill diameter? I looked at the manual for the attachment and it only references certain Delta drill presses. (see below)...

"The 17-924 Mortising Attachment converts your drill press into an accurate mortising machine and can be used with
the following units:
11-980 Drill Press (10")
14-070 Drill Press (14")
17-925 Drill Press (16-1/2")
11-990 Drill Press (12")
11-090 Radial Drill Press (32")
Delta Utility Drill Presses (15")
14-040 Drill Press (14")
17-900 Drill Press (16-1/2")

I have a chance to purchase this attachment at a great price, but need to know if it will fit my 1-7/8" quill diameter...........Thanks, Butch

[John McClanahan]

The attachment probably comes with several bushing shims so it will fit a variety of drill presses, both Delta and other brands. I happen to have a Delta model that it doesn't fit. The quill does need to extend down an inch or more for the bit holder to clamp on properly.

John

[david brum]

I'd measure my quill first to be sure. Says it fits 66mm, 50.8mm, 48mm and 38mm quill sizes. These mortisers have plastic adapter rings which come in various sizes to adapt the unit to your drill press. My drill press met the specification but I thought the fit was too sloppy. I sanded down the exterior of the next larger size to get a really snug fit onto the quill. I guess what I'm saying is that if you're between sizes, it's not too hard to creatively problem solve.

[Butch Butler]

Thanks for the input, Guys............

John - Firstly, my old drill press is a Guardian Power model - definitely not for show, but it works well. The bottom of the quill has a 3/4" collar attached that mounts the lower end of the travel gauge and stop, so would I have to remove that to mount the attachment? Not that this is an issue, just curious.....total travel with the gauge installed is about 3"........diameter of the quill works out to 47.625 MM.

David - Do you think I'm close enough to the 50.8mm size to make it work?....I think I could take some off the inside with a spindle sander or whatever works................Thanks again, ButchQUILL TRAVEL.jpg

[david brum]

David - Do you think I'm close enough to the 50.8mm size to make it work?....I think I could take some off the inside with a spindle sander or whatever works................Thanks

I think I'd try the 48mm spacer first. 3mm is a lot to take off, although easily doable.

About your depth stop, I don't have one like that, so please take whatever I have to say with that in mind. If it's possible for it to be positioned higher on the quill, it might make a useful stop for the mortiser attachment.

[John McClanahan]

Yes, it looks like you could slide the stop up a bit while using the mortising attachment. My quill extends below the stop ring, but its an "odd" size. I agree with Dave, the 48mm should work.

You may want to read up on user reviews for the model you are considering. There is more than one style of fence, and some people comment (complain) about setup and adjustment. Also, some of the low priced kits don't include the bits.

John

[david brum]

Oh, one last thing; If you happen to have an XY vice, you will have much better luck with hollow chisel mortisers in general. One major annoyance is a cheesy hold down. Instead of the chisel sliding out after the cut, it pulls the workpiece up with it. An XY vice solves that and allows you to advance the cut easily. I picked one up cheaply at Harbor Freight a few years ago. It lives on my drill press.

[Rod Sheridan]

"The 17-924 Mortising Attachment converts your drill press into an accurate mortising machine and can be used with
the following units:

Well, not really, the drill press attachments are neither accurate nor a good substitute for a mortiser.

1) A drill press quill has no fixed orientation. It can rotate back and forth many degrees since it doesn't matter when drilling a round hole. A square hole is different.

2) Drill presses aren't meant for that much downward force, they're meant to drill, not be used as a press to force a chisel into wood. Compare a drill press construction to a mortiser construction.

3) Leverage and rack and pinion strength. Look at the small teeth on the rack and pinion and the short lever arm on a drill press. Compare this to a mortiser and you'll see the differences.

I once owned one of those Delta drill press attachments, gave it to someone I didn't like and purchased a General International mortiser to replace it.

Tremendous improvement.............Regards, Rod.

[Harvey Melvin Richards]

"The 17-924 Mortising Attachment converts your drill press into an accurate mortising machine and can be used with
the following units:

Well, not really, the drill press attachments are neither accurate nor a good substitute for a mortiser.

1) A drill press quill has no fixed orientation. It can rotate back and forth many degrees since it doesn't matter when drilling a round hole. A square hole is different.

2) Drill presses aren't meant for that much downward force, they're meant to drill, not be used as a press to force a chisel into wood. Compare a drill press construction to a mortiser construction.

3) Leverage and rack and pinion strength. Look at the small teeth on the rack and pinion and the short lever arm on a drill press. Compare this to a mortiser and you'll see the differences.

I once owned one of those Delta drill press attachments, gave it to someone I didn't like and purchased a General International mortiser to replace it.

Tremendous improvement.............Regards, Rod.

I have a Delta Mortising Attachment that lives on an old Rockwell drill press. I find that it works almost as well as a Powermatic Mortiser that I had used previously. The real key to successful mortises is very sharp hollow mortise chisels. Let the tool drill the hole. Don't try to punch the hole.

I have built dozens and dozens of chair and stools with this attachment, and like I said, as long as it's sharp and properly adjusted, it works fine. If you burn the wood, or need to hand to pull the quill down, you're not doing it right.