Machine hang during tool change

[spock]

"Buy me a ticket to visit you (and return!) and I will fix it for free. You buy the parts! (LOL)"

How about you send me to Australia, teach me some things about electronics in cnc's, and send me home! Ha!

Machine cost about 40k. I have the best Fanuc man I know coming tomorrow.

I do use GO for rapids in a program. i agree that a toolchange sequence should leave the machine as it was, that might be the problem.

[javajesus]

My symptoms are the same as Spock, but we have the OI-Mate-MB control. I thought electrical noise might be the problem too, but we just moved the shop and had the place professionally rewired. Whatever the fix is, it will be worth the money. I hate walking across the shop to fix this machine. Other than this little bug, it has been a great workhorse. Spock, I hope you will let us know what the repair man says. BTW, who is he and where is he located?

[spock]

The guy coming over is Ron Jones, lives in Somerset, Ky. Drives up north to work alot in Ohio. Should be here in an hour or so, and we can get on this. I will keep you posted.

On Edit: I hope he gets here early....I am so convinced that the machine will act up when cold I have the bay door open and no heat on. It was 27 degrees this morning, hasnt warmed up much. I am staying in the office until I have to change parts on the lathe...brrrrr

[spock]

Pbmw,
could you send me a copy of your toolchange macro?
shopprints@hotmail.com

[spock]

Here is what repairman found:

He watched the plc section while machine was cycling, watching for the spindle orientation signal to make. This happens when you rapid up then come back down to tool change position, when the spindle orients for the change. When the spindle orients, the signal is good and now the carosell can slide over to do it's thing.
Here is what happpens: sometimes the z axis goes up, comes back to tool change position, the signal comes in on plc just like it is supposed to, then disapears, like you hit reset or like something somewhere cancelled it. We saw this every time it hung up. The signal for spindle orient was gone, so the carousell doesnt do it's thing, because the spindle is not locked now and would not stay in place when the "cup" hit it. So the machine does what it is supposed to, "nothing".

Now, what made the signal disapear? If it was a bad photo eye (that reads the spindle location) why did it send a signal in the first place? Why do it randomly?

Here is what he did: in the toolchange macro, near the very end, there are two lines that give you back control over single block (#3003=0) and over feedrate override (#3004=0). He put in a dwell line right in front of them, (G4X1.0). Now, after a tool change, there is a dwell of 1 second before the machine takes off again. He explained why but I dont know if I can explain it clearly.
I put the machine in a loop, running a short program with toolchanges, so it will just keep on running, and it has been going for 3 hours or so with no malfunction. I am running it all day, and I will test it again in the morning when it is cold.

The only other thing we can think of is to change the toolchange macro so that you dont loose the ability to override during toolchange (remove the #3004=1 at the beginning of macro). That way it is not looking for the two signals in the plc that determine the rapid rate, it just uses whatever rate you set on the switch. (The macro takes control away from the switch so that it will move as fast as possible in Z axis, for faster toolchange, getting the control back to you is where we think the problem is, hence the dwell.)

I would still like to see some macros on machines that are not hanging up, to compare, and I will keep you posted.

[javajesus]

Spock, you are the man! I will give this change a try in the morning and see how it works out. I will run a little program in a loop and see what happens amd post my results as well.

PBMW, I would also like a copy of your tool change macro. I sent you a PM with my email yesterday, but I will change my profile to get email from members.

[spock]

Well, ran for 4 hours, then something somewhere gave out, got a 1850 "magazine out of position" alarm, so i dont know if the sensor went bad or the brake, repairman coming back first thing in the morning.

[javajesus]

Hopefully just a dirty proximity sensor in the magazine. Keep us posted.

[PBMW]

I've had a couple of people ask me for my tool change macro, so I thought it easier to just post it here...


:9001
#3003=1
#3004=1
IF[#100EQ#4120]GOTO99
IF[#4120EQ0]GOTO99
IF[#1011EQ1]GOTO99
G91G28Z0.
G91G30Z0M19
M9
M6








































G04X0.1
IF[#1008EQ1]GOTO10
GOTO99
N10G91G28Z0
IF[#1009EQ1]GOTO12
GOTO10
N12G91G30Z0
G04X0.5
IF[#1010EQ1]GOTO99
GOTO12
N99#100=#4120
#3003=0
#3004=0
M99
% 

[spock]

PBMW, thanks, very similar to mine, looks like mine has more dwell, and then the newly added yesterday.

Javajesus, I removed about 200 lines of "end of block" characters so you could see it clearly.
Also, we traced the "magazine out of position" to a faulty switch, the prox. that is right by the cam shaft. My repairman thinks this could possibly be the root of the hangup problem, by not signaling correctly. He thinks the logic program might not be setup to catch it and asign an alarm, so it is laeding to the hangup problem. I will have a new switch in tomorrow, so maybe Friday I will know something new.

Also, the switch I pulled from my machine is not the one in the book, so if you ever have to order one, be sure and check what you ave in your machine.

%
O9001
#3003=1
#3004=1
IF[#100EQ#4120]GOTO99
IF[#4120EQ0]GOTO99
IF[#1011EQ1]GOTO99
G00G91G28Z0

G91G30Z0M19

M9

G4X.4

M6
G04X0.4
IF[#1008EQ1]GOTO10
GOTO99
N10G91G28Z0
IF[#1009EQ1]GOTO12
GOTO10
N12G91G30Z0
IF[#1010EQ1]GOTO99
GOTO12
N99#100=#4120
G4X1.0
#3003=0
#3004=0
G90
M99
%

[timlkallam]

Heres mine but I have two 9000 programs 9001 and 9020
I don't know what the 9020 does if any one knows please let me know.
%
O9001
#3003=1
#3004=1
IF[#100EQ#4120]GOTO99
IF[#4120EQ0]GOTO99
IF[#1011EQ1]GOTO99
G91G28Z0.
G91G30Z0M19
M9
M6
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
;
G04X0.1
IF[#1008EQ1]GOTO10
GOTO99
N10G91G28Z0
IF[#1009EQ1]GOTO12
GOTO10
N12G91G30Z0
G4X.5
IF[#1010EQ1]GOTO99
GOTO12
N99#100=#4120
#3003=0
#3004=0
G90G49
M99
%
Here is the other 9020 program what does it do.
%
O9020
N1IF[#20EQ#1032]GOTO9
N2#101=#4001
N3#102=#4002
N4#103=#4003
N5#113=#20
N6G00G91G30Z0
N7M06T#113
N8G#101G#102G#103
N9M99
%

[javajesus]

Well, the mill ran ALL day without an issue !!!!! Woohoo! Spock, next time you are in Spokane, WA, the drinks are on me. Thanks to all for your help. I was able to get the dwell time down to .500/sec to get rid of that awkward pause. I tried .1/sec, but that was not enough. Maybe I will try .250 tomarrow. It's quite a nice feeling not having to babysit the machine all day. Thanks PBMW for yout tool change macro, When I get a chance I will give it a try.

[javajesus]

we traced the "magazine out of position" to a faulty switch, the prox. that is right by the cam shaft. %

Spock, When you say cam shaft, where do you mean? On the magazine? Also, do you have the 10 tool magazine? I was wondering if the hang issue was a faulty switch or just software moving too fast for the machine. Can you take a picture of where the faulty switch was located?

[spock]

What the sharp book calls the "cam shaft" is the shaft that comes out of the little motor that turns and rotates the drum. The switch threads down next to the shaft and reads a little plate that goes around with the drum. You have to look for it thru the side door. It's a bugger to get to.
I have a 16 tool drum.
I wonder, sharp used a different switch than the book lists. There is some time duration in the plc. If the ladder logic was written with the specs for a certain switch in mind, and the switch installed is slightly different, it causes the problem? I will run that idea by the repairman when he comes back to install the new switch.
i know, it's just a switch, but if it doesnt fix it I want him there to start figuring out why.

[javajesus]

I'm jealous. We have the 10 tool magazine, but it is our first one. We are already shopping for another. I think I know what switch you are talking about. There are 3 on the magazine that I could see. 1 for the tool pocket, 1 on a rail that the magazine slides on ( looks like a pain to get to) and 1 on the inside of the magazine, not really sure what it is for. Are you going to test the new switch without the new dwell setting? It does make sense that Sharp programmed the machine for one switch and some guy on the floor used another spec switch. That might explain why it is hanging. Keep us posted.

[spock]

Well, what a week!

Got the new switch in on Wednesday, put it in, alarm goes away and plc reads like it should. Worked about 2 minutes, then the alarm came back (magazine out of position). But the switch was working this time, so new problem.
Pulled brake off the top of the magazine motor and found new problem, on one of the brake pads is a hex bore that fits the hex shaft on motor, it was chewed out completely. Magnet in brake works fine, didnt seem to be stuck. Only theory I have is that when the switch was going bad it might have been signaling at teh wrong time, which would activate the brake while the motor was still turning. The brake pad/bushing loses the fight.
On a positive note, after 4 days down I finally got the dealer to call me back, and they are working with Sharp in CA to find the part. Only problem seems to be that there is no listing for this part in the book diagrams, so Sharp is having to hunt it down.
It is weeks like this that make me wonder why I stopped working for the other guy....

[javajesus]

Sorry to hear that you are still down. I had a little scare today when my mill lost home. Turned out to be a chip hanging out on the prox switch on the X axis. I did talk to Ed at Sharp regarding the tool change hang issue and he said he would look into it and see what he could find out. For the time being, I am just happy to have the machine run a full cycle. Thanks again Spock and keep us posted.

[spock]

Sharp is sending me a new brake, so I should be back up Monday.

My repairman has a theory on the hangup, I will run it by you and see what you think:

He says that the toolchange macro is processed in a different section of the control than regular programs, and that because of the speed at which these things process it could be "jumping" back into the section where regular programming is run, before the macro is actually finished, (and has populated the plc with the correct info before it takes off again). this might explain why the machine is using the 100% rapid on all G0 moves, (from the macro) and is hanging up at the next toolchange, and why the dwell fixes it.

I do plan to reduce the dwell amount some and see what happens.

[javajesus]

I got my dwell down to a 1/2 second to where it's almost not noticeable but is still a little. I am going to play a bit and see where I end up. The repairman's theory makes sense to me. It could be any number of things causing it and we may never know.

[neilw20]

I got my dwell down to a 1/2 second to where it's almost not noticeable but is still a little. I am going to play a bit and see where I end up. The repairman's theory makes sense to me. It could be any number of things causing it and we may never know.

Timers are not a very good programming strategy.
Event driven is best.
You should only use timers to catch unexpected hazards (like a tool missing etc.)