Jet 708582 JMA-582 Mortising Attachment

The fence that comes with the attachment is not compatible with the Jet Drill Press Fence (709109). Quick modifications can be made so that the "hold-down" part of the attachment will attach to the fence, but when extracting the chisel/bit with hard wood, there is enough upward pressure to pull the t-tracks up away from the fence table.

After having tightened the set ring replacement as much as possible and still not having it hold, it may be tempting to over tighten the regular set ring when you remove the attachment to use the drill press in its standard form. CAREFULL. The set ring can crack and break if overly tightened.

A real disappoointment.


Great chisels, Mortiser needs work   August 18, 2000
 35 out of 35 found this review helpful

Jet's mortiser is heavy, well machined cast iron but the hold downs were not bent to the same radius or cut to the same length. This doesn't effect how I use the system but it may be a consideration for anyone who will not develop their own hold down and fence system to work with their particular drill press.

The fence is a piece of hollow plastic that needs some better way of being clamped tight and square to the drill press's table. (Assuming you can square it with the chisel mounted in the chuck.)

I would suggest buying the chisels from Jet. They are better than the two 10 year old chisels I have from Delta. These chisels and bits are really sharp! Mine have stayed that way although I haven't pushed them through anything harder than soft maple.

Be prepared to spend a lot of time setting up this mortiser to your drill press. Make engraved markings on the drill press head and chuck "shoulder" to readily square the mortising attachment to the table and fence. I would recommend that you build your own fence system and hold downs.


Worked well with little fuss after initial puzzlement   June 10, 2000
 31 out of 31 found this review helpful

I got the mortising attachment with my Jet 16 1/2" drill press. I have to admit that I was a bit stumped during the initial installation as there were no pictures of the installed unit and no narrative telling me that set ring on the basic drill press needed to be removed to install the chisel holder.

Once I got past the set ring issue things went well for me. However, you need a 6mm Allen wrench to remove the set ring and this is not included with either the drill press or the mortising attachment. I can see this being a real annoyance if you don't happen to own a 6mm Allen wrench.

On performance, the tool functioned very well right out of the box. The chisels were sharp with no noticeable burrs. I have cut test mortises in fir, pine and maple thus far and it does the job. I didn't notice excessive heat build up with this mortising attachment as I had with a ShopSmith attachment I used in the past. No smoke thus far! There appears to be sufficient support and sufficient clearance of the bit within the chisel.