Stepped clamps for rotary table

[Arbalest]

The counterbore will not lower the profile.  In effect, the body of the clamp has to be made high enough to engulf the head of the SHCS.  The clamp itself would be lower if the screw head stood proud.

True, counterboring the screw makes it impossible for anything to catch on the screw head, but I fail to see how that is very important in this application.

Have a look at the drawing Marv. If you didn't sink the bolt into block the bolt would stick up another 8-10mm. You could make a clamp with a step in the top to lower the profile but that would be less rigid for no advantage.

Here are some commercial clamps without the counterbore.

[Arbalest]

Some more clamps I've seen on the net.

Not low profile but nice and solid, the bolt is also nearer to the item to be clamped than the pivot point which is good.



These pin type aren't so good. They are counterbored to keep the bolt out of the way but the bolt hole should be nearer the pin for best clamping pressure.



These aren't ideal either, the hole should ideally be nearer the pin.



Some nice home made toenail clamps (at least that's what I call them) as the ends are rounded to fit in the recess in the vice! Clamping bolt nicely placed on these.

http://1.bp.blogspot.com/_aNjK3CTQ0DE/S4WAd3TGLUI/AAAAAAAAJ4c/EfVqGt_BdNI/s1600-h/peetrees08.jpg

[PStechPaul]

I found that my mini-lathe chuck fits my rotary table pretty well:



I also wanted to see if a lathe chuck jaw would fit the slot, and as you can see, it does, just barely. Here is a closer view:



So I came up with an idea of how to make adjustable jaws for the table:


It should be an interesting project if I decide to try it, but it looks like a lot of work. Probably better to just get a plain chuck and mount it on the table, or just use clamps. But this would give a lower profile. What do you think?

[Arbalest]

The principle looks ok, I'm not sure the jaws are a good enough fit in the slots though?

[PStechPaul]

That jaw was from my 4" three jaw lathe chuck. It was just to demonstrate how it might look. Here are two videos of what I have come up with, so far:

<a href="https://www.youtube.com/watch?v=GRmomud4kqM" target="_blank">http://www.youtube.com/watch?v=GRmomud4kqM</a>

<a href="https://www.youtube.com/watch?v=-BJBvHVtdzM" target="_blank">http://www.youtube.com/watch?v=-BJBvHVtdzM</a>