[Bob La Londe]

I have to say that I am a bit disappointed in the performance of the 2.2Kw spindle. I've calculated all the loads at less than one horsepower, and it bogged down and tripped the inverter a couple times. It has also already developed some end play, and it sounds almost like the bearings are dry or nearly dry. I need to take it apart and check it out soon. I'm not sure HOW to take it apart though. The back cap opens the water passages and exposes the electrical wires going into the motor from the connector. (There was no frame ground as I expected so I connected one.) There is an oval shaped bolt head with two flats on the back end of the shaft. If I need to grip that I'll probably have to make a socket to do the job. There is what looks like a threaded lock ring on the front end of the shaft with pin wrench holes on the face. Its made of aluminum so the usual short cut of tapping it with a punch and a hammer probably isn't a good idea. I'll probably have to make a pin wrench for it unless one of my angle grinder pin wrenches just happens to fit.

[purple_jeep]

Hi Bob,

Your Inbox is full

Also with the Lube pump there are actually two timers in the original setup, one that triggers every 15min or so (mounted on the side of the right cabinet) which drives a time delay relay (mounted on the relay board right cabinet) which actually drives the solenoid for the lube pump. I am trying to work out the delay on the relay as I bet that is also what you are missing.

Cheers

Chris

[Bob La Londe]

The electromechanical timer is a time delay activation. All in one. You may have a different setup.

[purple_jeep]

That's quite possible the documents on http://www.cnczone.com/forums/hurco/...downloads.html don't show the relay but the documents I have do show that on the relay board (if you still have it, I threw mine out before I realized) the left top relay should be a time delay one and all the other 7 should be regular relays.

If you want to check and send me the part number for the top left one we could confirm for sure .

Cheers

Chris

[Bob La Londe]

Very little of the original equipment is in the cabinet anymore. Most of it finally went in the dumpster a couple weeks ago. I only have a handful of relays, and they are all new 5VDC ones controlled by my breakout board. Anyway the timer is an electrical clockwork dial with a gap. It takes about 15 minutes to do a full cycle. When a roller on a microswitch reaches the gap it operates the 3 way solenoid valve that sends air to the lubrication pump. A while later the back end of the gap engages the roller and it closes off air and vents the pressure on the lub pump side.

[GT390]

Hi Bob,

Your Inbox is full

Also with the Lube pump there are actually two timers in the original setup, one that triggers every 15min or so (mounted on the side of the right cabinet) which drives a time delay relay (mounted on the relay board right cabinet) which actually drives the solenoid for the lube pump. I am trying to work out the delay on the relay as I bet that is also what you are missing.

Cheers

Chris

This makes sense to me, I have the timer like you have Bob, the 15min mechanical one, but everytime it fires off the contactor bangs in and out a few times as the micro-switch comes off and on the cam, I was thinking that it sounded like it would be really hard on the contacts in the mico-switch, I had even thought of installing a timer relay, did not realise the standard setup had one. I think I still have all my old relays, must dig them out and take a look

[GT390]

Bob, did your machine have the mechanical hand wheel speed control with two speed gearbox on the head ? I started to get some noise from the head will doing a job today, sounded like a bearing had gone, I have pulled the whole thing apart today but cant find anything worn enough to be the cause, the spindle bearings seem fine, the noise did seem to be coming from high up on the head near the speed control, and there was a lot of heat up there too. I am going to replace all the bearings up there anyway, looks like there are three or four, all just regular ball races. I do hope its not the spindle/quill bearings. Did you have yours apart after yours failed Bob ? If so, what are the spindle bearing like, are they some special one-off type, or do you think they may be available at reasonable cost ? now would be a good time to change them while everything else is apart, can you offer any advise Bob ?

[Bob La Londe]

No, mine was just a direct drive 1:1. There is another bearing though. The one in the drive pulley that drives the splines. Atleast on mine there was.

[GT390]

Ahh, my machine is a kmb-1x so the head is different, there is a bearing that sits inside the brake shoes held in a cast iron carrier, I have managed to break the carrier whilst trying to extract the bearing, looks like I am out of action for a while till I can find one, or make a new one

[Bob La Londe]

Ahh, my machine is a kmb-1x so the head is different, there is a bearing that sits inside the brake shoes held in a cast iron carrier, I have managed to break the carrier whilst trying to extract the bearing, looks like I am out of action for a while till I can find one, or make a new one

Youch. I so feel for you. If there wasn't a continent and a pond in the way I'ld suggest you pop over see if any of the part's I've removed would work for you.

[purple_jeep]

For completeness here are the drawings from the manual I have showing the Lube Time delay relay.

Attachment 243396

[GT390]

After having another look at the bearing retainer when I got home from work today, I have realized that it will be a simple enough task to turn a new one up on the lathe. still unable to find the cause of the noises I was hearing from the spindle drive, but I have the whole thing apart so am replacing all the bearings in the vari-drive head anyway. After taking a good look at the part I was machining, it appears that chatter may have been the cause of the noise, now that I see the way that the high and low gearbox gearbox engages the spindle, I am pretty sure any chatter could translate to some serious noise at the top of the head. A closer inspection of the "feel" of the spindle bearings themselves has me more concerned, I can detect no movement in them, but when I rotate the spindle by hand, now that all the drive is disconnected from it, I can feel a very slight "knotchy" feel to it. I guess now is the time to change them while its all apart, and now I know everything is going to work, I may as well get the mechanical side of things as good as it can be. Looking at the parts book, it looks like the spindle has a set of angular contact bearings at the bottom, and a single roller at the top. I am really hoping that these will be of standard type/sizes that will be available from the local bearing shop. Anyone reading this changed kmb spindle bearings before ? The parts book I have is for a SM-1 but it looks the same, it only gives hurco part numbers for the bearings though

[Bob La Londe]

There are 4 roller bearings on the carriage that ride on the front and back of a rail. Chatter when cutting can cause noise to come out of the head if these are not adjusted to contact lightly and roll against their rail when the quill goes up and down.

[Bob La Londe]

When you get them out you may find another manufacturer on the bearing and bearing numbers.

ACBs? Really? Is your mill rated for higher RPM than most (mine)? Mine was rated at 3600, and when I spoke with somebody at Hurco once they said, "DO NOT RUN THEM FASTER." LOL. I never looked that far into my quill, and never will now since I am totally changing my machine. I would have thought they would have precision tapered roller bearings.

Anyway, if they are ACBs or any other kind of bearing you can measure them and find the right size, then its a matter of choosing quality replacments and getting the preload right when you install the new bearings.

[GT390]

The speed dial goes up to 4000rpm, so I guess it must be a little faster, I hopefully will be able to get the bearing sizes from a contact I have tomorrow, the parts book I have is for an SM1, but it looks just like my machine, mine is a KMB-1x, I think its the same as a KMB-1m also, they dont have the roller bearings and guide in the quill as far as I know, I have it apart and cant find them...

[Bob La Londe]

Yours does not have the big square head does it?

[GT390]

No it has the vari-drive head, looks the same as the later hawk machine

[Bob La Londe]

So there is no stabilization for the quill other than the sleeve?

On my KMB1 the carrier clamped onto the back of the quill, and then up above the carrier had 4 rollers that stabilzed the whole thing against rails built into the head.

I would think light fast cutting rather than heavy hogging should always be your method of choice then.

[Krell33]

My KMB-1M manual has a parts list for the head assembly which lists 6203 and MM9306WI bearings. I did a quick Google search and see these are Timken numbers but should be easily cross-matched. I can scan the page if you need.

Dan

[GT390]

My KMB-1M manual has a parts list for the head assembly which lists 6203 and MM9306WI bearings. I did a quick Google search and see these are Timken numbers but should be easily cross-matched. I can scan the page if you need.

Dan

Yes please Dan, that would be great ! I have also read today that a VFD can drive a motor much faster than the motor is rated if it was running on direct mains power, if that is correct I will have to rig up some kind of tach to calibrate the speed, not being well educated in these things, I had thought that as the motor was rated at 1425 rpm, that that would be it`s maximum speed when hooked up to mains, or by being ran flat out by a VFD, it appears this is not the case. As my machine also has a gearbox and a vari-speed head I have no idea what RPM the spindle is actually making. If the machine is labeled to run at 4000rpm max, with a 1425rpm motor then the gearing must be 2.8:1 at top speed, if the VFD can run the motor up to 50% beyond the rated speed, as I have read, then the set up has the potential to turn the spindle at possibly almost 6000rpm, I dont think that would do it much good !!