Hurco KMB-IS CNC update

Leith,

Ok here is the schematic from hurco for the axis control. This of course is not the entire set of schematics, but this one page will give a lot to look at for figuring out how it was set up. When you have questions, don't hesitate to ask. It will take me a while to get the schematics together and plus I need to see if I can upload the manual through the forum or I may need to email you direct. File size will be the issue for putting up here.

Ok when you look at this schematic, you will see the TB-8 connector in the top middle. Some of the wiring on the left side of the connector is what will be taken out. I will show you what to remove and what to keep. Hopefully yours is still all intact and exact as this. If not, then get a picture and I will try and help walk you through it.


Talk to you later,
Robert


You can save the PDF file and open up to see a lot better than here on the forum.

Leith,

Ok this is a tangent, but I remember seeing one of the encoders installed on the black servo. I am sure it is one of BEI's friction fit encoders, and I have attached a schematic for it.

Originally Hurco had a different set of BEI/Duncan encoders, but if you had the original B control and wanted to upgrade to Hurco's BX control, such as what I had; then they removed the bolt on encoders which were 200ppr and installed these type that were 1000ppr. I am sure it is going to be pretty much the same as what I have as mine was upgraded and they are this type.

This messed me up for a bit as I had plugged 200ppr in LCNC when setting up only to remember that they were 1000ppr. This was bad at first for software stepping, but super excellent when I got it working through the Beckhoff EtherCAT hardware.


Back in a bit,
Robert


Same as before, you can download the PDF and see it better.

Hi Robert,

Out for a couple days mountain climbing.

My cabinet looks very similar to yours. Biggest difference is the servo amps in the upper left corner.

And thanks again for all the helpful data, schematics, etc.

With a huge amount of help from you, I've formulated a plan of attack.

1. Read the MAX-400 instruction manual. For me this is the biggest unknown and key part of the whole thing. To some degree, everything revolves around the servo drives. Already noticed the 85 VAC input?? Kinda weird. But this means I want to try and use the existing power supplies.

2. Get the compressed air system fixed up. Haven't looked at it closely, but I did notice there is a broken gauge.

3. Look at getting the oiler working. Again, haven't looked at it closely. Never worked an oiler before. Adventure in the offing!

4. Take a look at the E-Switch. Hopefully the schematics help, but given my level of familiarity with this beast, its going to be a bit dicey to be be sure I know I've got it right. I'll probably take the belts off the drives for initial power up. Spin the motors that way at first. Test the E-Switch, etc.

5. Try to find the X and Y limit switches. I've seen the Z limit switches.

6. Study schematics and get an idea how the power supply works. Probably detach all the loads and then... apply power to the supply. I'm not so keen on applying power to the supply, but why not. Standing well out of the way. Once the smoke clears, measure the outputs and make sure they're in spec. Its probably a pretty simple linear supply. If some outputs are broken or out of spec, shouldn't be too hard to fix. Look at the electrolytics. May chose to pre-emptively replace the electrolytics. Might save an end mill down the road.

7. Armed with the knowledge of how the servo amps work, jumper up the control inputs such that no movement is commanded. Apply power to the servo amps and hope for the best.

If this goes well, I'm sorta at the point where I can begin to think about connecting up LinuxCNC. It would be nice to manually cause the servos to step... but not sure how to do that yet.

At one point I'd considered gutting the electronics box. But now I'm thinking of a more surgical approach. The old Hurco computer will definitely be removed, but hopefully I'll be able to reuse the servo amps, the power supply, the relays, not sure what else.

One question I have is I don't understand why the quill drive has both a VFD and manual speed changer? Seems like you need one or the other??

Leith

Leith,

Nice, would like to be in the mountains again.

Ok let me respond real quick and I will respond better later.

Your numbered items

1) The servo amps take around 80-85volts and that was the norm for Servo-Dynamics amps. If you look up the Specs from Westamp the max the amps could take was 100V, and 92V continuous. Because of this, I am sure Hurco put in a safety factor using the 85V to not overload the amps as there would definitely be bigger machine shops that would be running the machine literally continuous. Time is money in machining and you have to keep the thing running to be profitable. My machine was $44,000 in 1983 from the paperwork, that was a ludicrous amount of money at the time... and still a lot of money today.

Ok so that you are aware the power supply that I pointed out in the control cabinet picture is NOT the power supply for the amps. That power supply is rather large and at the back of the machine in one of the compartments. I will have to look again at which one. But he power supply in the cabinet is way too small and you will see when you see the correct PS at the back.... it's pretty large.

Its been a long time since I read about the Electro-Craft Brushed DC motors, but from memory seems that the 80 volt range was optimal for the motors.... I can be wrong about this as it has been a long time since I have read about them. SO I am sure they were trying to balance out between optimal for the amps and motors.

On a tangent, you were speaking before about the problem with the motors having brushes. True that you can have brush maintenance and dust from them, but this really is only a issue for machine shops that run the machines every day. I doubt you will be cranking the machine up very many times a week. For me, depending on what projects my Dad wants to do, regulates the use. I may go a week working the machine everyday, but there are weeks that go by where I am on other projects not needing it. SO the real issue with the brushes is how much are you really using the machine. If you did change them out, then yes it is good to go brushless, but for me its a waste of money until you have something die and then change it.


2) Pretty sure gage is changeable without removing air block, but could be wrong. I will take a look at mine when I am back at the shop later today.


3) Yes, Oiler could be a hassle, I have been lucky and not have to re-build it yet. Will be waiting for your repair video


4) Ok I can save you a ton of time on the E-stop. It is literally 2 connections off the TB-3 connetor that make a loop with the E-stop. switch. Super simple.. I have the safety chain schematic for E-stop also... will upload later. Also, you will need the compressed air working for the E-stop chain to work. AS I said before, Hurco had a ton of safety implemented and it is needed for safety. The compressed air switch is to make sure you have air pressure at the brake for emergency stop of the spindle. This took me a few days to figure out without any help.


5) Ok I will get you a picture of where the X and Y proximity switch rails are located. On my machine they are the following: X as you face the machine is to the lower right under the table on the knee and the target is visible. The Y is at the back below the table and you will see the target off the table. Will get you pictures. Plus how to wire the 3 wire connection.


6) Ok don't take any wiring apart, let me show you what to detach and you should be good. There is a no need to remove anything unless its a safety reason during the retrofit.

LOL like the magic smoke reference. But honestly unless something is really really wrong you shouldn't get magic smoke LOL


7) Will get with you about how to "move" the table or quill but this is not for the average guy who does not understand what can go wrong. I will be detailed of how to do it making sure you understand as you can destroy one or all the axis if it takes off one way.


OK YES surgical approach is best. You will save a ton of time and all of the work done by Hurco as you will be re-wiring items that don't need re-wiring. You will have the machine up and running way way faster if you keep everything and resist the urge to gut it. I had to fight myself at the beginning and glad I did not gut the machine.

VFD could have been for someone using it with single phase input to get three phase to the motor. Plus most likely getting rid of the parajust board, as if I remember correctly they were single phase input with three phase output like a VFD can do.



Hopefully this helps.

Will be back later,
Robert

Leith,

One other thing that I forgot to mention. I have not seen your pendant, but when I went back to the picture of your machine which is really small and I cannot make out much detail, but it looks like you may have the dual screen Ultimax I or II control. If you get a better picture and of the inside cabinet I can tell you for sure. If it is, it will have Ultimax in orange on the black pendant.

I am beginning to think you have a much newer 90's era machine. If it is a black pendant with 2 screens then yes it is a much newer model. I have heard both good and bad about Ultimax, but have not used it. I doubt you have the parameter tapes for the machine and therefore cannot get the control loaded again, so it would not matter. BUT if you did get the parameter tapes, you could always try to load the machine and get it working back OEM. I was always wanting to retrofit our 2 Hurco's when we got them, but ran OEM until computer lost parameters and was glitching once in awhile anyway. To be honest I had learned Hurco's control really well. I could sit at the machine and code from memory into the machine and run parts. Now this was basic parts without elaborate machining processes, but non the less fast. Hurco had 2 ways to run their controls, Traditional and Conversational. If I remember correctly Hurco was the first to introduce conversational control, which is huge for small job shops and simply machining. I really never used the conversational control as I was so verse with traditional code control.

If you do not have the parameter tapes and the Ultimax is truly gone, then the pendant would not be worth wiring into. That is why I rebuilt the face and added pushbuttons for a temporary setup until I build a nice pendant that tailors to my style of machining. You may be able to wire into it, but on mine it had a board up in the pendant and not a easy way of integrating, so I gutted the pendant as that was the only thing not worth saving. You can send a pic of the inside of the pendant and I can tell you more.



Robert

Leith,

I realized a few minutes ago that I stated it was a power supply in the rear cabinet... it's only the transformer and when I was talking about the power supply in the cabinet, I was referring the the transformer on the power supply its self. Sorry, figured I should clarify as I miss worded what I meant to say earlier.

I will probably go back and revise that post so it is not incorrectly worded.


Will be back later,
Robert

Hi Robert,

Once again you have provided a terrifically useful piece of information.

On the back of the machine there is this brown thing about the size of two shoe boxes. Obviously a transformer. Can find no name plate or identification.

Its just about the right physical size to power 3 1+ horsepower motors.

Its attached in a somewhat crude way. Not what I would expect from the Hurco factory. But now I suspect it got upgraded with the motor drives.

The left, or power side cabinet has been mostly gutted. Apparently when someone removed the original, and I think broken VFD. I will have to hook it all back up with a new VFD. But was hoping to get the servos working first. I may need to do that sooner rather than later to power the servo amps.

You're right about expected duty cycle of the restored machine. It will be a hobbyist machine with very low duty cycle. But for the brushes, I don't know their current condition. And worse, don't have a part number for replacement brushes. Right now I'm just hoping they have enough life left forever at the hobbyist usage level.

I don't have a picture with a useful view of the pendant.... but I think its got a single screen. I'm still of the opinion this is an early 80's machine.

I think there was a tape in the drive. Hard to imagine the tape drive works. Not real interested in attempting to resurrect the old Hurco control. Was expecting to remove the old display etc and replace it with a laptop or LCD display.

I'll get a picture of it.

Hurco was $44k in 1983. For calibration, I bought a new Porsche for about $23K in 1983.

Leith

944