T20-437 on a RZ990

[Sonosuke]

We own a Risograph RZ990 which gave the above T20-437 error and made a strange whizzing sound. Both of them are now gone, but I'm leery about running it without a service call. What is the meaning of this T20-437 error, and should I be okay without the service call?

[joelsa12]

the problem is with the ejection part of the machine. the motor that drives the belts that paper come out on is where the error is pointing. i have found that the bearing that support the shaft that tighten the belt go out. and then friction will cause the shaft to be ruined. there is also an encoder sensor in there that will build up a lot of paper dust. i would blow out the sensor and inspect the bearing/ shaft while you are in there. if you are not going to do it I would call a tech out to do it if that bearing is out it will cause lots of problems if not fix and will get more and more expensive as you let it be.

[Sonosuke]

I appreciate the quick response, Joelsa, I've notified both my boss and my pressman (I'm in the unenviable position of being the middleman.) My pressman believes he knows what bearing you're talking about and can get at it, clean it, and the sensor. My boss has made the decision to put that off till tomorrow, he's got 3500 11x17 impressions planned before we do the maintenance on it. I hope that doesn't cause much problem. Thank you very much.

[Sonosuke]

We weren't able to find the specific bearing/shaft you were talking about, however we blew enough paper dust out of enough sensors that I think it's safe to say that's the issue (for now.) My PERSONAL opinion is to still call a technician, however my boss is dead set against it. We'll have to see how it goes now that everything is as clean as we could get it.

[joelsa12]

if the bearing is going out there will be an audible noise coming from the transport section. there are three rubber belts that transport the paper out of the machine. under the rubber belts on the ends there are "pulleys" that tighten and drive them. these "pulleys" are attached to a silver metal shaft and on the ends of the metal shaft are the bearings which seat the shaft into the frame of the transport section. that is about as descriptive as i can get. good to get the dust out the encoder should be functioning properly now

[Sonosuke]

We found what you were talking about, about ten inches into the machine I think, unfortunately we're just not confident enough to get at it so we've got our tech coming out to take a look at it. However we did get a LOT of paper dust out of the machine, the gears, the sensors, some of which we're wondering how they weren't causing problems because there's no way they were sensing anything.

At the very least that's been worth something and I've convinced my boss to let us set up a regular maintenance schedule where we pull it open and blow out everything we can with some canned air, cleaning out all the paper dust we can. (we get more than your average print shop because we run perforated paper done on a rotorary press through it, so you also get the perf dust in the machine.)

I appreciate all the help you've given me. If it's something facinating then I'll get back to you here once our tech takes a look at it.

Thanks!
Shaun