Mounting Unimat 3 Dividing Head to Unimat 3 Cross Slide

[WM183]

Hi folks.
I need to make a jig to assemble locomotive wheels in P48. I have a Unimat 3, and do NOT have the milling column or attachment bit. I want to mill the slots in the jig for the spokes by holding the jig in my 3 jaw, on my dividing head, with a 30 tooth plate (I need 15 spokes). I will hold my end mill in a collet chuck on the lathe's spindle, and just use the cross slide to control feed and mill my slots.

HOWEVER, unlike my old Unimat SL, it seems like the CL of the dividing head when mounted to the cross slide is not the same as the CL of my lathe's chuck? I can mount the Unimat 3 dividing attachment directly to the ways on the lathe bed, but... have no idea why I'd do that? My old Unimat SL would have done this, but of course, I could not get a collet chuck for it so milling was a no-go.

Do any Unimat 3 owners know if I can do what I want to do without buying some kind of vertical slide fixture?

I need to make a fixture thus: Scratch Building Some Drivers

 

[Rob R]

Pictures and measurements of the dividing head and unimat please..

 

[WM183]

Hi Rob.
After some banging and bodging, the answer seems to be "No" at least without a vertical slide. The dividing attachment can mount to the bed of the lathe itself (why?) or horizontally or vertically to the cross slide. However, nothing lines up nicely in that configuration. Thus:

 

[Rob R]

How about a piece of angle iron, or a block, mounted onto the cross slide with the dividing head mounted on the said angle/block but to the side of the cross slide so it can be dropped down to the right height?
I know a picture would explain it better, will try and sketch something when I get home if you haven't already sussed it.

 

[Stuart Birks]

In the first picture your left thumb is by a couple of slots. Can you mount it on that face which the CL of the head is much closer to the mounting face and have some sort of clamp in those slots. It would mean doing somthing like Rob R suggests by having the plate hanging off the edge and so below the hight of the cross slide.

 

[WM183]

Hi guys.

I should probably just hunt down the milling column. Don't suppose anyone has one to part with....?

 

[Andrewnummelin]

It may be worthwhile asking on the Unimat group on groups.io or other model engineering forum.

Topics

groups.io

 

[Rob R]

Amanda,
Basic sketch attached.

Use a bit of 10mm/12mm round bar between the headstock chuck and the dividing head chuck to get the vertical alignment then bolt the DH to the cross slide with a suitable bit of angle iron or similar, using the side of the cross slide as a datum face.

Rob

 

[WM183]

Rob,

That is BRILLIANT. Thank you! Oh my word.