Hello from Grenoble

[Doddy]

Electronics with lids removed.

Oooer, Edward - can't recall if we've spoke about the SX2.7 before now - currently I'm still on manual spindle control - have you found any alternative? (you're obviously using the standard speed controller).

[Edward]

Ho Doddy, I converted one of the first ones to come in, so that's a while ago. But I haven't done anything about the spindle control yet. I am tempted to swap the motor for a Delta servo or similar, preferably with a motor frame that will fit inside. Or maybe I will find something slightly more powerful with higher revs, but I haven't found anything viable for a reasonable price yet.

[Edward]

Doddy, are you using a secondary e-stop button to stop everything, including PSU to XYZ motors, controller, etc? This is what I am doing at the moment. I just found that the mill e-button carries the 240V mains L and N straight from the socket.

[Doddy]

Doddy, are you using a secondary e-stop button to stop everything, including PSU to XYZ motors, controller, etc? This is what I am doing at the moment. I just found that the mill e-button carries the 240V mains L and N straight from the socket.

Mine now just carries the Live. I've re-purposed the second pole of the E-Stop to send a control signal back to the control electronics. I don't look at the E-Stop to provide isolation from the mains - I look at it to effectively take power from the spindle-motor - good enough for shed-ware.

EDIT: But if you had a mains relay you could slave an E-Stop signal from the returns from the E-Stop control.

[Edward]

The way I am going to do it is to have an outside 12A relay that will feed the mains to the mill. This is the equivalent of pulling the plug out of the mill socket, but done safely with a relay. And the same relay will also control de 24V e-stop circuit, etc. The mains input will first go through a Schneider double pole Mcb.

[lewiss66]

Thanks to both of you for the info about the back cover. At the moment I don't have any lift to move the crate unfortunatly and with the Covid19 can't rent anything. Will keep posting my progress status. I will probably first start working on my spindle binding issue. I'm waiting for Arceurotrade to contact me tomorrow to give me instructions. Wait and see...

[lewiss66]

Hey Mike,
When you were talking about your spindle lock problem, you said a far-east R8 tool holders don't engage the anti-rotation nipple inside the spindle. Could you show of picture of this type of tool holder?
Thanks

[Doddy]

I have maybe a dozen toolholder, some give me no problem, some - mainly the ER32 collet holders that I bought from one Chinese vendor on eBay give me all sorts of gip.



View from under the spindle, looking up - you can just make out a round nipple just before the taper inside the spindle. That is, I understand, intended to engage with the keyway on the R8 collet.



This R8 collet holder is problematic... If I offer it into the spindle properly aligned there's no problem, but if, as I tighten the draw bar the tool holder rotates (not difficult) then the spindle binds and becomes stiff to rotate. I can only release the tool holder by rotating it until it aligns again with the nipple.

This second toolholder (all silver) ...



...doesn't have this problem (I cannot rotate this more than a couple of degrees when it's seated in the spindle, before I tighten the draw bar). You can see the keyway extends much closer to the taper on the tool holder.

I had tried manually re-cutting the keyway on a couple of spindles with some success.

EDIT:

From what I can see I think it's the depth of the keyway cut into the tool holder. Particularly with the arc at the end of the keyway as the depth reduces. At this point the tool holder can revolve and "jump" the nipple out of the keyway.

[lewiss66]

Ok I see. Thanks
Are you sure it's not due to some tool holders not compatible with our mill?

[Doddy]

Apart from the 5/8" drawbar (and not the alternate 12mm size) unless I'm wrong, an R8 is an R8 - I'd expect it to fit.

Whether it's the tool holder that's out of spec, or the machine, I'm unsure.

From previous conversation you demo'd without a toolholder installed and still had a binding spindle so clearly it's not the toolholder that's at fault with yours. I think you also demo'd without the belt from the spindle to the motor - the motor was erratic but very low speed - I guess 10rpm (default from start on a Sieg) so I wouldn't expect the motor to be super-smooth at that RPM.