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Jeff Belany
09-04-2013, 1:17 PM
Been having some issues that very much look like a dirty encoder strip. But there are a couple things I don't understand -- I did a Rowmark plate with about six lines of type. The first two were straight then one line was slanted and then the rest was straight. My first thought was some dust in the reader -- took it off and blew it out and things seem to be OK. One question -- is there any method to clean the reader other than to blow it out with air? Is there anything that needs to be cleaned such as optics? I do try to clean the strip regularly but in the last week I have cleaned it several times. This morning I did a test (on tape) and it was fine but when I ran the piece the letters slanted. I reran the same file and it worked fine the second time. Since I do a lot of one off's screwing up one is a big deal.

Any suggestions on anything to try? I can replace the strip easy enough but since it works most of the time I'm wondering if it's something else.

Thanks in advance.

Jeff in northern Wisconsin

Chris DeGerolamo
09-04-2013, 1:42 PM
I use qtips and distilled water up and down both sides until it's clean, it usually doesn't take long. I always make sure the encoder is dry before installing the cover on the gantry.

Dan Hintz
09-04-2013, 2:02 PM
Are you cleaning the IR LED transmitter/detector pair? If all you're cleaning is the strip, you're missing 50% of the equation.

Bruce Volden
09-04-2013, 2:04 PM
I also use q-tips and a magnifying lens (old eyes)!! One other thing is to closely inspect the cogged pulleys on the servo's that drive the belts, I have seen them get pretty "gunked" up and have had to clean them out with dental instruments. One wouldn't think something as trivial as this could cause problems but, hey, you know the snowball effect. Also look for debris in the valleys of the belts too!

What Dan said too!! I call this a contrast reader as the encoder fits into this and can accumulate crud!

Bruce

Jeff Belany
09-04-2013, 2:11 PM
How do you recommend cleaning the reader? Water? Alcohol? As far as the gears getting gunked up -- would this cause intermittent problems?

Jeff in northern Wisconsin

Martin Boekers
09-04-2013, 2:49 PM
I use a lens cleaner and lens tissues. I fold them a few times then wet with lens cleaner and rub within the channel a few times, then finish off with canned air.

Joe Pelonio
09-04-2013, 7:41 PM
The other problem is that over time you can get a break in one of the wires in the ribbon cable. Sometimes it helps to remove and install with the ends switched because there are more than are used. I did that and it worked, then ordered a new one to replace it and kept that one as a spare.

Dan Hintz
09-04-2013, 7:41 PM
How do you recommend cleaning the reader? Water? Alcohol? As far as the gears getting gunked up -- would this cause intermittent problems?

Jeff in northern Wisconsin

Martin's suggestion is good. And yes, it can cause intermittent issues... a dust bunny rolling around in there can intermittently interrupt the beam. If the machine is reading those interruptions as slots on the encoder strip, each line will be slightly off, which can manifest as italic-looking text.

AL Ursich
09-04-2013, 10:26 PM
This is an example of a Rotary Encoder on the back of a Servo Motor on the hobby CarveWright Machine. A See Through version of the Encoder as seen by the sunlight shadow. And what happens if you don't get the dust cap back on correctly.

A Strip Encoder like the Laser is reflective or see through but same theory. Counts pulses after bumping into a stop or home position.

AL

Bill Cunningham
09-05-2013, 8:51 PM
My encoder strip problems turned out to be as Joe said, the ribbon cable.. I've had the same strip in my machine for 10 years without a problem. I do keep a spare on hand just incase