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7/8" hollow chisel auger

Anyone know if there are still any likely walk-in sources for Greenlee/Forest City style augers for American pattern hollow mortising chisels, 7/8" size?

Rochester, Syracuse would be close enough....

Typical head popped off in first plunge of last mortise in series, only another few to go with same set up. Better than midway because it can be finished with a hand mortise chisel. But not so convenient the next 24, which are one plunge each (square) for muntin bars.

Failing that, I'll probably silver solder on a HSS slug to end of the old one, and reshape it.
Or go to home despot and find a bell-hanger or ship auger of suitable size to regrind/re-purpose. :rolleyes5:

smt
 
Well that was apparently optimistic. :)

I seem to have gotten old. Remembering the days when you could walk into WT WEaver in Georgetown or WS Jenks in Chinatown in DC (both gone)and get anything up to at least 3/4", maybe 1", and others may be laying around in the drawers. Assume more populous/industrial areas were even better?

So, where has all the old stock gone to die? I did call Bart Slutsky/Hudson Hardware and he only has odd and ends of smaller stuff. Forest City does not offer 7/8" anymore. Greenlee does not make HC anymore.

Is there a Wadkin source in the US? I know their bits won't fit American pattern chisels, a long time ago I bought one of their augers for a 1" chisel and it is larger. (Wadkin chisels have bigger bores for same dimension chisel compared to America) But the bits could be ground down on the OD with small effort.
Are Asian sets all that is available, and where can you get a 7/8"/22mm Asian HC set in the US?
I like the asian pattern, though the augers are pretty coarse for an autofeed machine. The 3/4" necks on the chisels over 5/8" are kind of small, too.

smt
 
Just Googled WS Jenks...They still have a store front in the DC area but based on the offerings found on line you would have wasted a trip...Sad!
They relocated out to Bladensburg Road. Fries Beall and Sharpe has a location out near my house but their web presence is pitiful. Good luck Stephen. You may have to build something after all. At least you are capable of it!
Joe
 
Don't you hate it when that happens?

Fixing the one you have will probably be the best out of a lot of bad options.
 
Not walk in but have you tried Bobby at Woodworkers Tool (1800 475 9991). I believe that they having been trying to buy up Forrest and Greenlee NOS and used bits/chisels for reconditioning. I was able to purchase some NOS and reconditioned Forrest bits to match up with some NOS chisels I came across. The bits that were resharpened looked to be as good as new.

MILO
 
I sent wtw an email request (no one available at phone).

Woodworkers Supply
https://woodworker.com/14-mortising...123-881.asp?search=hollow chisel&searchmode=2
appears to stock 7/8" Japanese chisels, augers, and sets.

Working on the broken bit for now. It broke about 1" up the flights, so needed to add a shank extension as well. Welded that end and waiting to cool. Thanks for the confidence, Joe - we'll see what happens. :)

smt
 
I have an assortment of odd tooling,what is the diameter and length of the bit you need and i will check in the morning to see if I have something that would work for you.

CW
 
Thanks for the offers - will post photos & measurements later tonight. Still hoping to get this one operational for Sat, lol.

Per parabolic suggestion - good idea, that seems to be the ideal shape. I did buy a 2 flute bell hanger bit with the idea of a last chance mod. But they only had up to 3/4" locally, so instead of just starting with 7/8" and grinding the body down to 11/16", it will still be necessary to weld/silver solder on a wider tip. So decided to work with the old body.

more later.
Thanks!

smt
 
Here's the problem

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Greenlee 228 automatic mortise machine.

smt_brokenmortisebit2.jpg

The bit actually broke off slightly more than 1". So the length (shank) needed to be extended. I had concerns that the fluting would not extend completely up through the neck of the chise, but decided to proceed with a simple extension. 4140 slug. Oxy-acetylene welded with 7018 rod.

smt_brokenmortisebit3.jpg
smt_brokenmortisebit4.jpg

The shank was done first so I could grip the body in a collet and turn the welded area down.

The business end was faced off and a piece of 3/8" sq. M2 toolbit was silver soldered on.

smt_brokenmortisebit5.jpg

smt
 
The M2 blank end was rough ground to shape and then spun in on the surface grinder. It was also back relieved

smt_brokenmortisebit6.jpg

The ends were also done in a Hardinge fixture on the T & C grinder. But much of the shaping was free-hand to get it over quickly. The larger bit is factory new and included for reference. It fits a 1" hollow chisel, also shown.

smt_brokenmortisebit7.jpg
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The 7/8" auger was finish honed with hand stones after the above photos, and installed for testing.

Plunge a mortise to each side with a solid bridge between, then cut that out. It will be obvious by the tool track if the chisel sides are not parallel to the table travel (parallel to the intended cut)

smt_brokenmortisebit9.jpg
 
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The bit cut freely and I was pretty happy, until it went full depth and jammed.
After a few more tests and jams, it became clear that so long as the chips could clear through the side opening, everything went smoothly and was free-cutting. However, as soon as the bit buried the side opening and the chips needed to exit the top of the chisel, they packed up and created copious clouds of smoke, sometimes seizing up the 5HP motor. This was due to the loss of flutes in that area that would normally carry the chips through unimpeded.

smt_brokenmortisebit11.jpg

The stains and charring around the neck are new and indicate where the bit was packing up.

I freehand extended and blended the flutes on the auger. This did not work perfectly, but well enough to finish the mortises. It may be necessary to open up the window in the chisel as much higher as there is room. Greenlee's "hard service" chisels merely had an extra window (one on 2 opposite faces) with one place higher on the chisel for better chip clearance. That could be an option.

smt_brokenmortisebit12.jpg

Mortised up close to the broken bit with the new set

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Then dug it out with hand chisels and a screwdriver.

197901d1494049154-7-8-hollow-chisel-auger-smt_brokenmortisebit14.jpg


smt
 

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Regarding the question about dimensions:

Ideally, this bit would be 9-3/4" - 10" long OAL.
The flutes would extend for about 7-1/4"
The head/cutting end diameter is 7/8".
The main body diameter is "about" 11/16" to fit inside the bore of the hollow chisel.

One of the further reasons I did not use the bell-hangar bit is that the flutes would probably need to be opened up a bit (thinner flights). The flutes including the helix angle are somewhat critical to where they run smoothly and easily, and where they don't.

smt
 
Thanks, Joe; stuff like this makes me feel really stupid. How the heck do i let a job get in that situation anyway? Apparently except for searching old stock and hoping someone generous has a hoard, most of this stuff is gone. I had no idea. I will start to re-position tooling around the asian offerings. The Asian chisels are better, but the single flute/single flight augers are sometimes a problem on my autofeed machine even on the slowest stroke rate. Aside from dithering to avoid starting, it took from about 2:30PM local to 9 PM with meals & goof-off time out. So maybe $12 - $15/hr if the part holds up. Not real productive.

Here are some odds and ends showing the HC mortise process.

Greenlee #228 auto mortising machine. Ca 1920's. (could be late 19-teens) acquired early 80's from shop on Maryland's Eastern Shore. Rebuilt, re-scraped.

smt_brokenmortisebit19.jpg

The machine has provision for long bars & stop rods for production work. For a few pieces it is faster to layout with a pencil. Since only a designated face (all faces or all backs, not either or) is held to the fence, even "symmetrical" pieces are handed. (right or left) So setting a bunch of stop rods to make them all the same takes more time than layout.

smt_brokenmortisebit20.jpg

Good practice is to have the chisel cutting on opposite sides. So typically each end of a mortise is cut to the line (or stop). Then stepped off between with more or less equal spaces leaving bridges just slightly smaller than one chisel width. This also supports the cut better, and keeps the mortise sides from swelling or collapsing as they are cut.

smt_brokenmortisebit17.jpg

Then the bridges are cut out.

smt_brokenmortisebit18.jpg

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smt
 
Great repair Stephen!

OK, maybe not financially a smart move, but there's no price one can put on the satisfaction of solving the problem with your wits and skills. Plus knowing you can do it again if need be.
 
I worked at a lumberyard in the 80s that had a full window shop (sash and jambs) that went back about a century. There was a huge mortiser, about 7 feet tall, that I would have loved to get onto my shop.

Entire mill and shop burned down by an employee.
 
Steven:

A suggestion, based on the photos you shared: Once you've bored the holes along the mortise shoulder lines, instead of plunging the third hole in in the middle, which is thereby another hole in which the chisel is completely surrounded and you will encounter that problem with chip clearance and heat, bore the next hole adjacent to an outer one. Also, turn the chisel so that the evac slot faces the already-bored hole (pick a side) and you will instantly decrease the number of times you are boring with the chisel surrounded. That should reduce the problem considerably.

You don't need to worry about the bit wandering in the intermediate holes, only the ones on each shoulder line.
 
Chris-

both methods work, and both have pros-cons attached.
The chisel is supposed to be either surrounded; or cutting on opposite sides, but not on 3 sides.
I agree that it mostly works ok 3 sided, but it works better IME to cut squares and bridges in deep work in hardwoods. I'm probably too old to change my ways. :rolleyes5:

There are a couple longer series chisels in 1" & in 3/4" here. But in 7/8" I reground the shoulders on one of them (the one in use) so it is cutting 5/8" deeper than Greenlee intended :) .

smt
 
Been poking around in the old Greenlee catalogs, some from OWWM

It is interesting that Old Greenlee augers for "hard service" bits look kind of like the current Asian offerings. The single flute style are listed as superior for fast chip evacuation in small chisels, but were only made for the smaller ones.

The hard service augers for bits 1/2" and larger have 2 flutes & a brad point center. These are rated superior for hardwoods. I *think* I can vaguely recall a few in drawers at WT Weaver because they puzzled me, but have never seen them anywhere else.

I was trying to download pictures but the pages listed as 1.3KB in my files show up as 1.3MB on the PM downloader and won't load.

smt
 








 
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