[keithmcelhinney]

Well I made my last jig for my motorcycle clevises. Got everything cut and went to press in one of my locating pins and it exploded. With no real pressure on it. Didn't have a spare. So had to drill a temporary dowel pin in. OK no problem. Got it all set and cut a sample set (2 pieces). To my disbelief, they came out perfect. Awesome! Went to cut the remaining 5 sets and the mill throws a external stop requested when I was only in like 45 seconds. OK weird. Check my speeds and feeds and I am only cutting .1 deep on a long 3/8" endmill at 24ipm. And this isn't even a full width cut. OK says I can do it but maybe because the piece is not solid (the pieces are suspended and held in by bolts) I have to go slower. Slow the feed down and get in about 3 minutes and it happens again. OK. Change my speed to 18ipm and depth to .8. Again it happens. Can't figure out why. Keep playing with the speed and it keeps happening. After at least an hour of experimenting I pull the bit out to look at it and it seems fine, but I (finally) notice that it is sticking WAY out of the collet. I actually pulled the bit out. Take it apart and the inside is soaked with coolant. Clean it all up and try it again and it throws it again! WTF! Luckily I got in my 1/2 long endmill today and I switch over to that and everything comes out roses. Sucks that the hour cut took me 4 hours though!

I did shut off the estop just to make sure it wasn't that tripping because of vibration. I would have thought I would have broken the endmill before the machine would throw the estop. Weird.

-Keith:devious:

[kvom]

I had a problem with pullout with carbide on one collet in my Chinese set. Replaced that single collet with a good quality one and haven't had that problem since. Other collets are OK.

[keithmcelhinney]

Well it happened again and then I had a slap on the head moment. High helix endmills. Switch to normal HSS and no problems....

Dang it!

[jid2]

What are you holding the tools in? I use a 3/8" high helix in an ER 20 collet holder and cut at 200 ipm on the machine at work.

Also seems bizarre the machine is faulting. Sounds kinda Mach 3ish.

[keithmcelhinney]

It is in an er 20 collet. I am not sure what exactly happened but I switched and it ran...

[TiagoSantos]

Is this a servo machine? What exactly is making it throw the e-stop? Seems weird indeed. I've broken many endmills and had pullout problems, but never saw mach complain about any of that.

I've also used high helix carbide 1/2" end mills in er20 collets without issues. That really shouldn't be a problem. No one else mentioned it, but just in case - slowing down isn't always the solution. It's possible that you were already going too slow to begin with! Use a calculator (I like HSMAdvisor, or even the free calculator on his website) and experiment with things.. It's pretty important to maintain a proper chipload, so if you feel like going slower, you might also have to cut deeper, etc. Rubbing will lead to chip weld, which leads to $$$ down the drain and headaches!

[keithmcelhinney]

It is a stepper machine. It threw a "external estop requested". I didn't know it would do that either. Very strange. The spindle % was only around 20 so I don't think it was that. I don't know, but it pissed me off pretty good. I used HSMAdvisor to calculate the speed and feed, but went about 20 percent slower at first.

-Keith

[SCzEngrgGroup]

Keith,

That "External E-Stop" message is generally an indication of electrical noise, which can often be radiated noise from the VFD when it's under heavy load. Try re-arranging the wiring in the E-box to keep the high-voltage wires (the AC feeds and the motor cable) as far as possible away from any other wiring, and as close as possible to metal parts of the enclosure. This is not an uncommon problem with VFDs. If that doesn't do it, I'd try adding a few extra ground wires to make sure the VFD itself is securely grounded to the AC ground as close to the AC input as possible. After that, I'd suggest trying some shielded cables for the E-stop wiring.

Regards,
Ray L.

[keithmcelhinney]

I will check that out Ray. Thanks! Make more sense to me. It probably is that because I had to replace the power supply in the computer and may have moved something around.

-Keith

[LeeWay]

I have read that cell phones can act on it as well when being used in close proximity. I have threatened to take away both my employees phones a couple times for other obvious reasons, but I think that might create a mutiny. Let them have their grog.