Can someone explain camover?

[NJRaised]

Can someone explain camover? Is it good or bad? I have a rockchucker supreme.


From what I understand, when I lower the handle down the ram goes up, and at some point, the ram comes back down ever so slightly when I push the handle all the way down.

If I’m shoulder bumping .002”, do I want camover or is that bad? Wouldnt camover release pressure on the brass and cause inconsistent shoulder bump?

 

[Ruff 364]

Camover is when your press ram hits the limit, but you still have a little more in the handle. The ram is at max length and all the slop is out of the press linkage.

 

[RegionRat]

If the die body is screwed down to touch at the top of the press stroke, and then you snug it with your fingers, when you relax the press and then return to the top of the stroke the press ram will just stop where the handles stopped.

Now, very slowly in tiny increments, relax the press handle and slightly screw down the die. It will create a setting where a little more force is required on the press handle to get back to the top, but then the handles stop short. Then very carefully add a little more and you will come to a point where the press will toggle or "cam over" very slightly where the handles stop.

Now the press is actually flexing a little when the ram tops out and that stiffness or flex allows the press linkages to go slightly beyond (over center) the top.

Not every press is designed this way, but the Rockchucker is.

This is all just easier to demonstrate than to describe with words.

The purpose of camover is to make sure the die bottoms out with margin. For example, there is the opposite situation that is possible with a press that does not camover where the friction load of the work generates enough force variation that the user may accidentally not fully bottom the die. With camover, this is not likely. YMMV