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dp
02-19-2009, 12:12 PM
Tool curiosity has caught me. Anyone have and use a tool such as the Starrett No. 298 key seat rule or is that out of fashion? I'm replacing my lathe motor and need to cut a keyway and stumbled onto this tool.

http://catalog.starrett.com/catalog/catalog/groups.asp?GroupID=271

JCHannum
02-19-2009, 12:17 PM
The clamps can be used with any rule or straight edge to layout or measure a keyway or other feature on a shaft. I have a set and use them from time to time. A piece of small angle iron can be used for the same purpose in many cases.

dp
02-19-2009, 12:30 PM
My curiosity is along the lines of wondering what the world market is for these tools that Starrett and perhaps others still make them. I have a trammel that is similar in design in that it clamps to a rule and which is endlessly useful for compass work but this looks like it should have slipped quietly into obsolescence. Hence my curiosity. My first thought was to place an angle iron against the shaft, too.

JCHannum
02-19-2009, 01:01 PM
General makes them as far as I know, and maybe others. General also makes stair clamps and other rule attachments.

Man, being obsessed with gadgets, I am sure there is enough of a market for these sorts of tools to maintain a market for them.

ehughes
02-19-2009, 01:35 PM
Have a set & use them infrequently, usually when laying out keyways on the ends of a shaft too long to cut at one set up. A little more precise than an angle iron. Regards

Spin Doctor
02-19-2009, 05:40 PM
Well they probably made a 1000 sets thirty years ago and still have half of them on the shelf :D. I have a set and in 30 years I can count the times I needed them on one hand. Thankfully they are a family heirloom. But I would use them occasionly with a 24" or 600mm blade for layout work (that was a handy use, not a need)

tattoomike68
02-19-2009, 06:38 PM
I never seen or heard of such a tool, I still dont see how it works or what good it is. Does it help keep keys in time on shafts with several keyways so they are all on the same side and in line?

In shafts I know old school machinist who eyeball cut a flat then dial down half the key and go. its real fast.

I use the machinist Handbook and find dimention M then add half the key myself.

On long keys I like to use a horizontal mill, 20 foot full key is no problem.

JCHannum
02-19-2009, 06:46 PM
B&S lists them in their 1935 catalog, and they turn up pretty frequently in older tool chests.

They are a means of accurately scribing a line on a shaft and laying out two or more parallel lines. In the good old days, before everyone had a mill, it was not unheard of to lay out a keyway and cut it with a chisel.

tattoomike68
02-19-2009, 08:05 PM
B&S lists them in their 1935 catalog, and they turn up pretty frequently in older tool chests.

They are a means of accurately scribing a line on a shaft and laying out two or more parallel lines. In the good old days, before everyone had a mill, it was not unheard of to lay out a keyway and cut it with a chisel.


A chisel? that would suck. I have put woodruff keys on some super hard oil furanace pump shafts that a chisel or HSS would never even touch. you know the type, the shaft that a file just skates over it and not leave a scatch. The poor old file say " no way Jose"

Carld
02-19-2009, 11:16 PM
Well, I have a set of the Starrett rule clamps and used them a lot when I was working full time. I still use them from time to time.

I read about how machinists used a chisel to cut keyways so I tried it. All I can tell you is my keyway was crude and I never tried it again. :eek: I use endmills and woodruff cutters now thank you.;)

Richard Wilson
02-20-2009, 10:08 AM
I have my grandfathers keyseat rule and have probably used it once or twice. He was a colliery enginewright and I have certainly heard him describe setting out a 1" wide keyway on a shaft that couldn't be taken out, and then cutting it in with a hammer and chisel. Those old fitters would have a keyway cut in the time it takes us modern machinists to get set up. It might not have looked as pretty, but it did the job, and kept the coal coming up the shaft, which was all they were worried about.

Richard