Internet Horology Club 185
Gear Cutters
November 30, 2008, 12:23
Chris AbellGear Cutters
Just picked up a large quantity of gear cutters, plus attachments, milling head and not show but a set also for WW & PW gears. Never had cause to use these yet and a lot appear to be clock sizes. I see a they are marked from 0.55 M, 0.65m, 0,75M 0.85, & 0.95M, also marked are things like D9X, D1218X etc,
The thick wire set are marked with 3 & numbers, also where do the button type cutter used.
Can anyone explain the sizing etc.
November 30, 2008, 12:25
Chris Abell1
November 30, 2008, 12:29
Chris Abell3
November 30, 2008, 14:08
John WoolseyChris, you've got an absolute small fortune there in cutters!
The numbers such as '0.55M' and '0.65M' etc refer to the 'Module' of the teeth to be cut.
Rather than try to kill my brain explaining this, the following link will make things a bit clearer
http://www.geocities.com/mvhw/gearing8.htmlThe 'Button' type cutters you mention, would appear to be for cutting 'Recoil' type escape wheels as fitted to longcase and Fusee wall & Bracket clock movements etc.
If you're getting into gear cutting, I would strongly recommend you get hold of a copy of Malcolm J.Wild's edition of 'Wheel & Pinion Cutting in Horology'
http://www.amazon.com/Wheel-Pinion-Cutting-Horology-Historical/dp/1861262450A superb book by a superb horologist, and highly recommended.
Best regards
John
November 30, 2008, 14:22
Chris AbellThansk John,
Will go and take a look at the links, I love buying tools like this when I see them I figure if I don't use them or in later years can always sell them and get my cash out again.
The head looks good also, no doubt need more index plates, if I had a pulley could make the mill work also, more things to find

as is I take the gear to the cutter.
November 30, 2008, 15:06
Enzo LiguoriChris,
the M (module) you listed seem to me rather for clocks than for pocket', maybe the small cutters in the background are Modules for pinions and wheels for pocket (and wrist) watches...
You did good to buy them....I wish I would have same luck...congrats !
rgds
Enzo
November 30, 2008, 16:13
Chris AbellHere is a list I have just sorted them out in to groups, maybe someone can identify the to odd ball K & number ones at the bottom of list,
Also a photo of the small set with what I take to be pocket or wrist watch cutters
not a bad start to my gear cutting set up.
I may get another lathe and just leave it set up for these
M-0.55
6
7
8
10
12
W x 2
M-0.65
6
7
8
10
12
W x 2
M-0.65
9 x 2
10-11
12-13
55-134 x2
135 –X
M-0.75
6
7
8
10
12
W
M-0.85
7
8
9
10
12
W
M-0.95
7
8
9
10
12
W
M-0.55
7
8 x2
9
10-11 x2
12-13
14-16
17-20
21-25
26-34
35-54
55-134 x2
135 –rack x2
Odd balls below anyone tie them to a system
K8
298
400687
400938
401081
401034
403929
K70
K173
531
K269
302
K305
K329
K391
K363
K464
K543
4011-70
K2619
K1299
K1941/10
K1567
K1633
K3576
K3570
K36-17/9
K3828
K3292
K3293
K4472/9
N29T.80-18 S C CH.08
November 30, 2008, 17:08
Clive DriscollChris
I echo what has already been said and I have used these cutters to cut clock wheels.
They cost a fortune to buy, around £55, last time I checked.
So now I send away to have my wheels cut which is far cheaper than buying a cutter thatg you may only use once. You can make your own cuttter for a one of job but the cutters you have are far superior.
November 30, 2008, 17:16
Clive Driscollp.s the small numbers (in brackets) i.e module .55 (6) are for pinions. For pinions you need a seperate cutter for each pinion if the number of leaves are different.
For example to cut a six leaf pinion .55 module you need one cutter, For a seven leaf pinion .55 module you need another.
Unlike a clock wheel where you can usually get away with one cutter for a range of teeth.
Hope this helps.
November 30, 2008, 17:33
Chris AbellHi Clive,
So looking at the list I have above how much of a complete set do I have, would this be enough to meet most of your average needs as a clockmaker?
I have seen the mill head go for about $600 alone without a index, but I need a drive pulley, no doubt I could make one of those I also have a Unimat 3 that I could turn it on.
December 01, 2008, 17:10
Clive DriscollChris
If my memory serves me correctly module (for a wheel) is determined by the dia of the wheel (in mm) divided by the number of teeth. There is then slight rounding to get to the nearest cutter.
I believe, again from memory, that a longcase wheel is typically around .75 module (but I would need to check in the workshop if its that important)but I don't think its far out.
So what you have a good range of cutters but as your lowest module is .55 this would not go down to carriage clock size. I don't know about the odds that you list.
The pinions are calculated slightly differently. But again you have a good range of pinion cutters listed.
As to the dividing head this can be used to hold the wheel blank on a stub arbor. The cutter can be held in a stub arbour in the lathe.
Hope this makes some sense.
Kind regards.
December 01, 2008, 19:58
Chris AbellThanks Clive, Seems like the odd ball cutters would be for smaller clocks so have a pretty comprehensive set, not to mention the red box set so another good set of tools to have, also picked up a very interesting jewelling set will post later on for fun by Swatchild.
March 12, 2009, 12:54
J. Bruce WeeksWOW! Chris,
I am just getting set-up for gear cutting and this is a real treasure trove!
I received a quote from P.P. Thorton last Oct and it was 52.25 British pounds per cutter.
Congratulations!
March 13, 2009, 22:38
Chris AbellHi Bruce,
I sold the M set off as dont see myself moving over to clocks, I still have the bag bottom right that I may sell off later and keep the small cutter set for PW/WW
March 24, 2009, 12:56
J. Bruce WeeksHas anyone been able to identify the "oddball" cutters? The "K" and 6 digit numbered ones?
March 27, 2009, 16:36
Hubert F. Hockmuller"M" or Module is very easy to calculate you simply dividing the pitch diameter of the gear by the number of teeth of your gear you want to cut.
Go to the Machinery's Handbook Page 922 for more information.
March 27, 2009, 16:52
Hubert F. HockmullerOh! I forgot to comment on your Boley dividing head it is a very nice tool and a, must have, if you want to cut gears. I have one to match yours plus the Lathe and a complete box of goodies to go with it.
I'll put this on my site someday so more folks can enjoy these tools and accessories.