Mill issues

[JonL]

Whilst doing some trial machining yesterday I went to bring the quill down slightly, but I stopped the machine before doing so as I wanted to inspect the finish on the cut.

Process went:
1) machine past the edge of the material
2) stop the machine, open the guard, inspect the metalwork.
3) unlock the quill, using the fine feed bring it down a small amount, relock.
4) restart the machine.

At this point ERR came up on the display, I stopped it immediately. No rotation had taken place. I tried to move the shaft by hand, it had locked solid. 

A fair bit of head scratching, tried loosening off various clamps etc, at some point during this process (not sure when) it came free. When spinning the shaft by hand there was some notchiness, which then abruptly cleared. Moving the quill up and down on the main feed resulted in a little notchiness which again abruptly cleared.

After that everything went back to normal, but it left me concerned. I don't want to start things up only to have a massive crunch, I have run the machine and it runs fine, smooth and quiet, but I daren't take any more cuts.

Has anyone got any tips? I can't afford an expensive mechanical failure; I was barely able to afford the purchase. If something did go crashingly wrong I only hope ArcEurotrade would see it as a failure and not my having done something (although I can't imagine what I did wrong?)

[uuu]

Sounds like a foreign object or grit in the spindle. Or - is there a spindle lock at all (as might be used to hold the spindle whilst tightening a chuck)?

Wilf

[JonL]

Thanks Wilf, I'll have a look. There isn't a spindle lock I'm aware of, you just get a spanner that fits in holes at the base of the R8

[runner42]

You have probably by now become better acquainted with the mill and aware of things that can go wrong, such as not closing the safety guard and trying to start the machine. I mentioned that only because you mentioned opening the guard to inspect the finish but didn't specifically say that you closed it again. Assuming that you did the restart iaw the correct procedure and that your lock up was due to something not determined but subsequently cleared, I would not be over anxious about that issue, the mill is made to withstand a lot of abuse by users and something you can relate to it's like getting in a new car taking it cautiously at first but soon putting your foot down. 

Brian

[jasonb]

Any chance that the cutter may have come into contact with the work when it was lowered and you were trying to start against a stalled spindle?

The spanner that goe sinto the end of the spindle will benifit from changing thepegs to parallel ones as the tapered ones tend to try and jack themselves out of the holes.



Also check that you are starting and stopping the machine correctly, see PDF that I wrote in case you did not get a copy with the machine

www.dropbox.com/s/tzdz2bmw4ggtft0/Mill%20Operation.pdf?dl=0

[JonL]

Thanks for all the tips. I ended up stripping the top cover off and found the belt was very loose. Upon looking down alongside the motor I saw the motor connectors were rubbing against the gears that move the spindle up and down.I ended up taking it all apart, re-routing everything, then reassembling with an appropriate belt tightness (which being a toothed belt isn't exactly singing middle C).

I never did find out what caused the issue, and when the quill is at full extension there is still a barely perceptable grumble, but I suspect its not a worry.

My main reason for removing the top cover was to find out why my quill fine feed was floating so badly in and out. I suspect it was that the knob on the end of the worm drive had been pushed slightly off (by me? I don't know, its possible) which meant it was possible to move the fine feed knob in and out about 10mm or more. I found a roller thrust bearing under the knob so I figure the position of the knob on the shaft forms the adjustment of this setup.

It all seems to be working correctly now. I'll read and reread the instructions Jason has supplied, and I suspect that modification of the spindle spanner is a very good idea indeed. I purchased a cheap amadeal fly cutter but found you can't fit the spanner in to tighten the spindle....

[JonL]

Interesting that there isn't a power button, I had used the emergency stop button a couple of times but won't do that in future, thanks Jason. I wonder what detriment using the button causes? I may make a more convenient switch near to the front of the bench.

[jasonb]

Using the oval stop button ramps the speed down, using the e-stop shuts it off instantly so is a little kinder to the machine. Also the contacts in the e-stop are not meant for continual usage.

Yes some larger diameter tooling does get in the way of teh spanner, I prefer the arrangement on the KX-3 which is a hole in teh side to take a bar which is easier to see and locate the bar into, it also lines up with teh peg for the R* so you know where to put the tooling in.

What is your drawbar eject like, does it pop the taper right at the end of teh drawbars thread? with teh risk of dropping teh tool. I added a simple collar to the top of teh drawbar that way it breaks the taper after about two turns of the spanner and there is plenty of thread engagement to take the force.

www.dropbox.com/s/c8wstph11huzsaz/SX27%20Autoeject.pdf?dl=0





Also worth removing teh spring from the X-axis handle so it does not get caught up and it also makes it easier to feed evenly as you are not having to compress the spring, it's only really needed if you have power feed to save the handle whizzing round.

[JonL]

Mine is exactly the same as yours, but I'll be doing your mod soon! I'd already moved the spring from one side of the handle to the other. I may fit power feed one day and don't want to lose the spring.