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Black Forest
08-25-2011, 04:49 AM
This came with some tooling I bought. I have no idea what it might be used for.

The hole is 60mm in dimater. The slots are 16mm wide. The plate is 20mm thick.

The sides are just milled but the two flat faces seem like they were ground.

So what would it be used for?
http://i853.photobucket.com/albums/ab91/burnandreturn/whatisit.jpg

EVguru
08-25-2011, 05:19 AM
Change gears, either on a lathe or a dividing head.

Split clamp go around gearbox input shaft bearing boss. Gears are set up on studs mounted in the slots.

philbur
08-25-2011, 07:36 AM
Good one, but why two rows of slots?

Phil:)


Change gears, either on a lathe or a dividing head.

Split clamp go around gearbox input shaft bearing boss. Gears are set up on studs mounted in the slots.

J Tiers
08-25-2011, 08:31 AM
Why NOT two rows?

An alternative to the widely split arms of the regular "banjo" setup, especially if the gears are known to not be too big.

John Stevenson
08-25-2011, 08:59 AM
Good one, but why two rows of slots?

Phil:)

So you can drop a small idler in to reverse direction

philbur
08-25-2011, 10:36 AM
But can't you do that equal as easily with one slot. I can understand the advantage if the two slots where widely spaced.

Phil:)

John Stevenson
08-25-2011, 10:59 AM
Phil, with one slot you need to leave enough centre distance between a pair of gears to drop an idler in between.

With two slots you only have to leave a small gap and drop the idler onto the top slot.

Remember on a dividing head which is what this banjo is for, you may need 4 sets of compound gears to get the required ratio for the lead and an extra idler could lose you the room.

EVguru
08-25-2011, 11:31 AM
I thought later, that the style pointed towards a dividing head. Given the tickness and the ground finish, I suspect it's of Tiwanese/Chinese origin.

Black_Moons
08-25-2011, 11:42 AM
One long slot is less rigid then shorter slots.

Shorter slots however have a web inbeween each slot. Hence 2 rows of slots = highly rigid, and can put a gear at any 'distance'

Weston Bye
08-25-2011, 12:09 PM
This reminds me of the blind men trying to describe the elephant from only the parts they could touch. You guys are all gathered around the lathe part of the elephant.

Here's the view from my location near the elephant, no more or less valid than the foregoing opinions:
I've seen parts like this used as fixturing for special-purpose tooling on the mill table, as actuator or sensor supports on automation, as part of a tensioner support bar or wire guide support bar on multi-spindle coil winders, as....... the list could go on. Such a "bracket" could be used to make a transition from a flat surface to a tubular or bar stock support strut.

It's always fun to put an interesting or impressive. but non-relevant, detail in a box of tooling, then watch the guys stand around and scratch their heads.:D

Black Forest
08-25-2011, 01:05 PM
Maybe this was used on the mill X axis to drive a dividing head. The hole is the right diameter to slip on over the X axis if the handle is taken off. Then I suppose a gear(s) is mounted to drive the dividing head. It came in a box of stuff with the mill and lathe I bought this spring.

flutedchamber
08-25-2011, 01:26 PM
I think you have a piece of flat ground stock there. Whether or not it is imported I don't know. I guess you could measure the thickness and width to see if it is of standard size.

CCWKen
08-25-2011, 02:41 PM
Looks like a drilling table off a small drill. Maybe a post drill. I'll take it if you don't want it. ;)

3jaw
08-25-2011, 02:59 PM
I have to agree with Weston. It could be almost anything.

All of the answers so far are plausible but without seeing it used we don't really know. I've run into lots of oddball tooling and attachments over the years that would probably make perfect sense if I could see it being used but I couldn't make heads or tails of it.

jugs
08-25-2011, 03:55 PM
No....

It's a banjo from a a dividing head, I have an almost identical one (mine is a casting) on a Midgley & Sutcliffe dividing head.

works as below



Change gears, either on a lathe or a dividing head.

Split clamp go around gearbox input shaft bearing boss. Gears are set up on studs mounted in the slots.

John Stevenson
08-25-2011, 04:01 PM
Watch the lips:-

It's off a dividing head.

http://www.stevenson-engineers.co.uk/files/dividing%20head%20setup.jpg


Edit, Jugs beat me to it but I got prettier pictures so there....

beckley23
08-25-2011, 05:33 PM
Can also be used for differential indexing on the dividing head. Check the first picture in this topic.
http://bbs.homeshopmachinist.net/showthread.php?t=49078
Harry

CCWKen
08-25-2011, 07:28 PM
Well, not having the dividing head that it goes to, I'd use it on my post drill. :D :cool: