which hollow chisel mortise bits? and 917T questions

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by flitemedic13 posted 10-03-2016 03:52 PM 1889 views 0 times favorited 3 replies Add to Favorites Watch
View flitemedic13's profile


8 posts in 1336 days

10-03-2016 03:52 PM

hi all,

Im about to take the dive and probably buy the Powermatic 917T mortise but had a few questions.

I originally wanted a benchtop style but I have more floor space than bench space to give up. But by the time id buy the PM701 or equivalent bench top and a stand/mobile base and riser block, im just another few hundred from the big brother version that seems, in all accounts, to be superior to benchtop models. Is it worth the jump in price?

Anyway…Which hollow chisel mortise bits should I get? Powermatic, Lee Valley, Fisch, CMT, etc? I like the price of the CMT ones but not sure how premium they are given the price although I love the CMT saw blades and router bits that seem fairly top notch.

Will the Powermatic mobile base PWBS 14 fit this mortiser? everything in my garage shop is mobile in case I need to put the car in for bad weather. If this doesn’t fit ill probably throw on a generic one from woodcraft or rockler.

3 replies so far

View pintodeluxe's profile


5757 posts in 2958 days

#1 posted 10-03-2016 04:06 PM

I have the Jet floor mortiser, which shares the same castings as the Powermatic. It is a great tool, and you will never regret that purchase. It takes about half the effort to make mortises, compared to a benchtop unit.

I was figuring on upgrading to premium chisels when I purchased the unit, but found that it would accept almost any size or length of chisel. So I tried my Woodcraft brand bits. They were freshly sharpened with diamond cones, and pocket files and the results were fantastic. These same bits actually made cleaner mortises in the floor standing machine. I was breaking a lot of bits on my benchtop mortiser, usually the auger tip of the 1/4” bit would fail first. I haven’t broken one yet on the new machine, which I take to mean the larger mortiser is more robust with less flex.

I have tried some premium Jet chisels, and while some were good, I also got a 1/2” bit that was a dud. One of the tips of the bit actually bent over. I would still try the Jet / Powermatic brand bits again, but honestly the basic Woodcraft bits work really well. I have a Shop Fox set that I ordered from Grizzly. They work well, but need considerable filing to cut clean mortises.

The next ones I’ll try are the Lee Valley premium bits. However it is best to stick with either all short length standard chisels, or all long length premium chisels so you don’t have to remove or re-install the chuck extender.

Some more info here…

-- Willie, Washington "If You Choose Not To Decide, You Still Have Made a Choice" - Rush

View JBrow's profile


1366 posts in 1064 days

#2 posted 10-03-2016 09:53 PM


I have not owned nor used the bench top models so I cannot compare these machines to the PM 719T. I have used hollow chisels at the drill press and can say for sure that the PM 719Tis far superior. I suspect I would have said the same thing had I upgraded from a bench top hollow chisel mortiser.

A very nice feature of the PM 719T is the moving table. The work piece can be clamped in place and by moving the table, sideways or in and out, is really nice. The hold-against the fence clamp also works well. The spine on the PM 719T seems fairly stiff; I have noticed no flex. Its small footprint on the mobile base allows it to tuck out of the way until it is needed. The base offers a rubber lined shelf that is convenient for storing mortise related accessories.

I debated which hollow chisels to buy and ended up buying the Powermatic set. However, I have only used the ¼” chisel. It continues to perform well in walnut, the wood I typically use. It drives into the wood easily and does not wonder or flex even with slight paring cuts I typically make when centering a mortise. I did nothing to dress the chisel before using it. An inspection of the other chisels in the Powermatic set did not reveal the bent-tip problem mentioned by pintodeluxe for the Jet chisels. While I was spending all this money, I also bought a hollow chisel diamond impregnated sharpening kit from Rockler. I agree with pintodeluxe’s recommendation to either buy all short length standard chisels or all long length premium chisels.

I do not know whether the PWBS 14 fits the mortiser. A call to Powermatic customer service may provide an answer. I made the PM 719 mobile by constructing a 2×4 frame and laying 2 sheets of ¾” plywood on the 2×4 frame. The plywood was fastened to the face of the 2×4 frame (not the 2×4 edges). I mounted four swivel double locking heavy duty castors to the 2×4 frame. The PM 719T was bolted to the plywood. The machine is stable and the castors lock well keeping the machine immobile during use it rolls easily. I bought the castors from Peachtree for about $60 for the set. This shop made mobile base added 6-3/4” to the height of the table which at my height of just under 6’ is a good working height. The four swivel castors make the machine nimble which may not be the case with the PWBS14 mobile base, assuming it features two fixes straight-line castors.

If you are interested, my review of this purchase is at…

View flitemedic13's profile


8 posts in 1336 days

#3 posted 10-05-2016 02:20 AM

thanks for all the input! jonathan

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics