Rotary Attachment Problem

[Don Gares]

Okay, I uploaded a video of the non-working rotary attachment to one of my domains. If you just click on www.dongares.com/rotary_mpeg4.avi it should download and then play. If you have an average DSL or cable connection the download will probably take about two minutes. If you happen to be on "dial up" don't even try it.

Don

[Robert Walters]

Okay, I uploaded a video of the non-working rotary attachment to one of my domains. If you just click on www.dongares.com/rotary_mpeg4.avi it should download and then play. If you have an average DSL or cable connection the download will probably take about two minutes. If you happen to be on "dial up" don't even try it.

Don

Ok, you have multiple issues in the video...

1) The erratic speed looks to be a mechanical thing.
I see a set screw on the gear that connects to the motor shaft.
I'd see if that can be pulled off, it looks loose. Re-tighten as necessary.

2) I see a few belts in there, they might need to be replaced or adjusted as needed.

3) You have BOTH an encoder and the large disc with an interrupter (which might be for homing purposes).
Ignore the interrupter for now and check the connections to the encoder on the rear of the motor. It's that upside down 'U' thing about 3/8" thick, (well under that cover that is).

[Chuck Stone]

I'm thinking the other way .. I'm half blind, so I didn't see an encoder anywhere.
But the rubber disc and drive wheel seem to be tight with the motor, so I'm
thinking there's a problem with the signal getting sent to the unit. Could
be pinched wires, something crossing pins on a connector or a fried chip
somewhere.. but nothing about that looks like any normal operation.

Have you had a board replaced lately? Any chance the JP5 plug has
come loose or isn't seated right?

[Don Gares]

I'm thinking the other way .. I'm half blind, so I didn't see an encoder anywhere.
But the rubber disc and drive wheel seem to be tight with the motor, so I'm
thinking there's a problem with the signal getting sent to the unit. Could
be pinched wires, something crossing pins on a connector or a fried chip
somewhere.. but nothing about that looks like any normal operation.

Have you had a board replaced lately? Any chance the JP5 plug has
come loose or isn't seated right?

No offense Robert but I think that I have to agree with Chuck. All the set screws are tight and all the components in the unit are moving together, no slippage anywhere that I can feel or see.

I have unplugged and replugged all of the lines to, and within, the rotary attachment with no joy. I certainly wish that I had another rotary attachment to try on the machine. This test would tell me whether or was the attachment or a signal coming to it. Of course I don't have another rotary attachment nor do I have any clue as where to borrow one. I have never replaced the main board so it could be that but the balance of the machine works fine so at least part of the main board is working fine.

All in all, I need a tech person and I don't know where to get one. Your suggestions on locating one would be appreciated.

Cheers,

Don

[Chuck Stone]

I wish I knew where to find a tech .. , I'd even settle for GCC returning
a phone call or answering email!

If I were standing at the machine, I'd probably disconnect the power and
pull that JP5 plug and put it back a few times just in case there's any sort
of buildup on the contacts. Same with the plugs inside the unit itself.
I'd look closely at the serial plug to the rotary attachment.. see if there's a
bent over pin, missing pin etc. and give the whole thing a good cleaning
while I was there. (I'm sure it doesn't get opened up very often)

After that I'd probably re-load the software and see if that makes any
change. Do you have the loader program?

I really wish they'd make available some manuals that actually say something
more than "If experience this problem, find out why"

Just wondering .. the rotary wasn't plugged in or unplugged while the
machine was running, was it? I know the machine REALLY doesn't
like that

[Don Gares]

I wish I knew where to find a tech .. , I'd even settle for GCC returning
a phone call or answering email!

If I were standing at the machine, I'd probably disconnect the power and
pull that JP5 plug and put it back a few times just in case there's any sort
of buildup on the contacts. Same with the plugs inside the unit itself.
I'd look closely at the serial plug to the rotary attachment.. see if there's a
bent over pin, missing pin etc. and give the whole thing a good cleaning
while I was there. (I'm sure it doesn't get opened up very often)

After that I'd probably re-load the software and see if that makes any
change. Do you have the loader program?

I really wish they'd make available some manuals that actually say something
more than "If experience this problem, find out why"

Just wondering .. the rotary wasn't plugged in or unplugged while the
machine was running, was it? I know the machine REALLY doesn't
like that

Although I have inspected the pins on the connections I really did not expect to find a problem because the unit worked fine one day and not the next without ever being disconnected. And no, I have not connected it with the machine turned on.

There is no software for the laser that I can remember. Well, come to think of it, I guess that there must be a printer driver. Anyway, the problem exists no matter if the computer is turned on or not so it is probably not the driver.

I would think that there must be a tech person that travels around the county somewhere. In fact, I somewhat expected one to be on this forum but no joy. Guess that I simply need to find someone in this area that has similar equipment and see what they do for tech support.

Thanks again,

Don

[Robert Walters]

Have you physically removed and inspect *ALL* of the belts?


If you can...

Try taking another video using a tripod and post with a higher resolution (I have LOTS of bandwidth, so don't worry about the size).

Each time you move the camera, stay in each position for a longer period of time (10-20 seconds per camera movement, zooming, etc). Also try to both zoom in on areas, as well as zoom out to give perspective.

Here is the encoder. The back cover *should* be removable and there will be a disc inside attached to the shaft of the motor. The other round thing looks like it checks for shaft differential since it's belt driven.

[Don Gares]

Have you physically removed and inspect *ALL* of the belts?


If you can...

Try taking another video using a tripod and post with a higher resolution (I have LOTS of bandwidth, so don't worry about the size).

Each time you move the camera, stay in each position for a longer period of time (10-20 seconds per camera movement, zooming, etc). Also try to both zoom in on areas, as well as zoom out to give perspective.

Here is the encoder. The back cover *should* be removable and there will be a disc inside attached to the shaft of the motor. The other round thing looks like it checks for shaft differential since it's belt driven.

I will do what you suggested but first tell me how you make a still image fully show in the tread rather than show as a thumbnail?

Don

[Chuck Stone]

Here's a firmware uploader .. pretty easy to use. There's one version of
the firmware in the zip file, but you can substitute your own version.
Run the upgrader, select the firmware file and then link to your COM port
or LPT port, whichever one your laser is on.

Start the laser while holding the Start and Pause buttons (I think!.. check
your manual) and then start the upgrader. It will resend the data to the
board.

[Robert Walters]

I will do what you suggested but first tell me how you make a still image fully show in the tread rather than show as a thumbnail?

Don

Click on INSERT IMAGE in the thread editor (the yellow icon).

[Don Gares]

Have you physically removed and inspect *ALL* of the belts?


If you can...

Try taking another video using a tripod and post with a higher resolution (I have LOTS of bandwidth, so don't worry about the size).

Each time you move the camera, stay in each position for a longer period of time (10-20 seconds per camera movement, zooming, etc). Also try to both zoom in on areas, as well as zoom out to give perspective.

Here is the encoder. The back cover *should* be removable and there will be a disc inside attached to the shaft of the motor. The other round thing looks like it checks for shaft differential since it's belt driven.

Okay Robert, I took another video and I almost thought it has fixed itself at first but no luck. I think that you can see that there is no slippage of the belts or the gears on the shaft. Also the disk in the encoder is tight and moves with the shaft. All in all, it simply appears that the motor is getting a signal that it should not be. You should notice that when I do an auto focus it starts turning which it should not do. I really don't think that the problem is in the rotary attachment but I would gladly ship it to someone that had a similar machine for them to try. If it worked on their machine then I would be sure that the problem was in my laser.

Anyway, you will find the video at www.dongares.com/mvi_2002_mpeg4.avi

Enjoy,

Don

[Robert Walters]

Okay Robert, I took another video and I almost thought it has fixed itself at first but no luck. I think that you can see that there is no slippage of the belts or the gears on the shaft. Also the disk in the encoder is tight and moves with the shaft. All in all, it simply appears that the motor is getting a signal that it should not be. You should notice that when I do an auto focus it starts turning which it should not do. I really don't think that the problem is in the rotary attachment but I would gladly ship it to someone that had a similar machine for them to try. If it worked on their machine then I would be sure that the problem was in my laser.

Anyway, you will find the video at www.dongares.com/mvi_2002_mpeg4.avi

Enjoy,

Don

Have you removed all the belts and inspected them?














I was hoping you would move the camera around a bit so one could see the encoder moving as well as the position sensor moving, but eh.

Check for loose wires, including inside connectors.
Reseat connectors as well.

Also bump/thump/tap the machine, the fixture, etc. see if the problem is consistent or alters as you thump things.

You may have to trace the wiring harness back to it's circuit board.

Look for flat (instead of round) wires - like if they were smashed.


If none of that effects anything, with power off, I might unplug things and see if things change as an attempt to isolate where the problem.

Obviously I'm only going by a video, so I don't know what the electrical aspects of it are, but I'd suspect that if the encoder was unplugged the motor would start spinning consistently or not spin at all. All depends on how it was designed. If it doesn't, then I'd trace back and inspect the wires from the motor to it's circuit board in the machine.

[Don Gares]

Have you removed all the belts and inspected them?

I was hoping you would move the camera around a bit so one could see the encoder moving as well as the position sensor moving, but eh.

Check for loose wires, including inside connectors.
Reseat connectors as well.

Also bump/thump/tap the machine, the fixture, etc.(snipped)

Robert, you are a genius!

Once again I took the end panel off that covers the main board. With the machine running I unplugged and replugged the cable to the rotary attachment for the umpteen time and nothing changed. I then bumped, thumped, and tapped the main board and the rotary attachment stopped turning. I turned the machine on and off several times and all appeared as new. With limited confidence I put everything back together and engraved three wine glasses with absolutely no problems. On top of working again it no longer makes the horrible noise (you probably heard it in the video) when it is looking for the home position. It has made that noise since day one but no longer!

Thanks again for the high tech advice.

Don

[Robert Walters]

With the machine running I unplugged and replugged the cable to the rotary attachment for the umpteen time and nothing changed.

I'm glad you got it going!

BUT...

Plugging/unplugging a rotary attachment while the machine is on is a very bad thing.

Had this been a stepper motor and was energized, you would have blown the motor driver board. Thus why I mentioned "... with power off..."

I was going to wait till you got the rotary attachment issue resolved, then mention the limit/homing switch.

Be sure to check *ALL* wiring and cables in the system. If two somewhat major things were faulty, who know what else is too, including the laser.

Personally, I'd shut down operations for a day, do a complete PM (Preventive Maintenance) on the system. Clean, lube, rotate the tires, check belts, bearings, loose screws, alignments, etc.

[Don Gares]

I'm glad you got it going!

BUT...

Plugging/unplugging a rotary attachment while the machine is on is a very bad thing.

Had this been a stepper motor and was energized, you would have blown the motor driver board. Thus why I mentioned "... with power off..."

I was going to wait till you got the rotary attachment issue resolved, then mention the limit/homing switch.

Be sure to check *ALL* wiring and cables in the system. If two somewhat major things were faulty, who know what else is too, including the laser.

Personally, I'd shut down operations for a day, do a complete PM (Preventive Maintenance) on the system. Clean, lube, rotate the tires, check belts, bearings, loose screws, alignments, etc.

I just may try a bit of PM as I have never did any in the two years that I have owned it. Shutting down for a day is not a problem as I probably only use it once or twice a month. I realize that connecting and disconnecting things with the power on is a "no no" but we own a computer business and I have did it many times without any problems (knock on wood). This situation simply came down to trying it that way to observe any possible changes. It would not have been the end of the world if I had blown something.

BTW - there is one just like it on e-bay but it is only 12 watt.

Thanks again,

Don (now to fix the tach on my boat)