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blackcat4866
02-23-2021, 12:42 AM
I know, I know ... I should have taken a picture. The little support hook at the front snapped off. The drum claw assy is supposed to cam gradually front to back, but does not.

On the PM I noticed a distinct drum claw ring on the drum. The drum claw assy could not slide front to rear. The front hole had sagged 1mm and swelled around the shoulder screw. This machine ordinarily does 300K per month, but lately the volume has dropped off. I'm wondering if the machines internal temperatures are rising during idle.

I was able to re-shape the plastic with heat and a little filing, to make the drum claw unit oscillate properly. I am just concerned about obvious effects of high internal temperatures. The drum claws are not very far from the fuser. Maybe obstructed fans?

Has anybody seen this? =^..^=

BillyCarpenter
02-23-2021, 03:39 AM
The fans and ducts would be my first suspicion. How old is the plastic part that was affected by heat? Over time plastic ages/dries out and becomes more susceptible to heat. Is it possible it's just time to replace with new?

blackcat4866
02-23-2021, 08:21 PM
The fans and ducts would be my first suspicion. How old is the plastic part that was affected by heat? Over time plastic ages/dries out and becomes more susceptible to heat. Is it possible it's just time to replace with new?

I hope not. It's only 9 months old. I've seen very similar drum claw guides on 1052 with 15M prints and 5 years.

wjurls
02-24-2021, 06:58 PM
Plugged up ozone filters?

allan
02-24-2021, 10:15 PM
a Bad thermistor could lead to higher temp than what it reads? Gee that part should not get that hot and sure if it stays this way that issue would only be the fisrt problem it creates. Have not seen that section get that hot.

The air duct for the belt cleaning unit gets lost. But sure that would not happen on your machines. Anyway don't think that would affect that.

Set Low Power and Auto shutdown to 1min?

blackcat4866
02-24-2021, 11:00 PM
a Bad thermistor could lead to higher temp than what it reads? Gee that part should not get that hot and sure if it stays this way that issue would only be the fisrt problem it creates. Have not seen that section get that hot.

The air duct for the belt cleaning unit gets lost. But sure that would not happen on your machines. Anyway don't think that would affect that.

Set Low Power and Auto shutdown to 1min?

I thought about that, but there are some drawbacks. This machine has a 15 minute initial warmup from cold. Probably less from sleep mode, but still 5+ minutes. My keyop would have to be very patient.

The thermistors were not significantly worn ... I was in there rebuilding the fuser. I checked for blunted fuser claws, but nothing like that.

I'm going to investigate to see if is any way to run more of the fans during idle. =^..^=

allan
02-24-2021, 11:04 PM
For some sort of reference you can check the drum temp senor value against another machine.
Strange problem you have there.

blackcat4866
02-24-2021, 11:27 PM
Thanks for your thoughts. =^..^=

blackcat4866
02-27-2021, 09:17 PM
I have a little more information:

Firstly, it's exactly the same drum claw assembly used on the PRESS 1052/1250P.

Secondly, cooling fan/1 FM1 & cooling fan/2 FM2 are the two fans most closely involved in cooling the fuser and photoconductor areas. FM1 cools the fuser, runs at low speed during standby and low power mode, high speed during warmup and printing, & low speed during idle. FM2 cools the photoconductor area, OFF during standby and low power mode, high speed during warmup and printing, and stay at high speed a few minutes after printing, then OFF at idle.

I checked the service manual and DIPSW settings for possible changes to fan cycles or fan speeds: nothing found yet.

I haven't had an opportunity to investigate fan, ducts, and filters yet. I can be pretty certain that FM1 is at least running. It would throw a C5363 or a C5364. A stopped fan will flip DIPSW42-2 for wrong speed measured during high speed mode, and DIPSW42-3 for wrong speed read during low speed mode, and error out the machine. There is also ICP11 on the PRCB which would blow for an overcurrent, and error out the machine. On the other hand, for FM2 there does not seem to be a specific DIPSW, or ICP, but there is errors C5366 or C5367.

More to come. =^..^=

blackcat4866
10-21-2021, 02:08 AM
5M copies later: no re-occurrence. My MacGuyvered drum claw assembly is working just fine, with no additional heat deformation. Whatever occurred before has not repeated. =^..^=

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