[Misc] RP 3700 dark/empty spots, thermal print head problem?

[Guest]

Hi, My printer start making unusual scuff-like white marks and darker blocks like on these photos.

https://www.dropbox.com/s/3deh7kqbkylskdb/02.jpg

https://dl.dropboxusercontent.com/u/61161152/01.jpg

does anyone have been through this type of problem with rp3700? Think it could be that thermal print head needs to be cleaned but not sure what type of alcohol and cloth is ideal as I've never done it since i bought this machine.

Another thing worries me is the wrinkling with the black drum i have. With the black drum is installed Print Drum Meter is 1079919 (copy count:1078868/master count :1632), hope this will help to figure out what makes those marks..
Thanks.

[Iowatech]

Re: RP 3700 dark/empty spots, thermal print head problem?

Hi, My printer start making unusual scuff-like white marks and darker blocks like on these photos.

https://www.dropbox.com/s/3deh7kqbkylskdb/02.jpg

https://dl.dropboxusercontent.com/u/61161152/01.jpg

does anyone have been through this type of problem with rp3700? Think it could be that thermal print head needs to be cleaned but not sure what type of alcohol and cloth is ideal as I've never done it since i bought this machine.

Another thing worries me is the wrinkling with the black drum i have. With the black drum is installed Print Drum Meter is 1079919 (copy count:1078868/master count :1632), hope this will help to figure out what makes those marks..
Thanks.

First of all, I can't see your pictures just yet (thanks for including them though!). So what follows might be nonsense and feel free to ignore it.
That being said, thermal head issues tend to initially show up as thin blank lines on the prints in the direction of paper travel, and if you look closely you can see them on the master that's on the drum. So, best I can tell, I don't think the thermal head has anything to do with this.
You might try resetting the machine by holding down the "Reset" key while turning the machine on. Only do that once though.
Other than that, you might need to have the scanner unit cleaned. Or at least clean the platen glass.

[lambanogonline]

Re: RP 3700 dark/empty spots, thermal print head problem?

First of all, I can't see your pictures just yet (thanks for including them though!). So what follows might be nonsense and feel free to ignore it.
That being said, thermal head issues tend to initially show up as thin blank lines on the prints in the direction of paper travel, and if you look closely you can see them on the master that's on the drum. So, best I can tell, I don't think the thermal head has anything to do with this.
You might try resetting the machine by holding down the "Reset" key while turning the machine on. Only do that once though.
Other than that, you might need to have the scanner unit cleaned. Or at least clean the platen glass.

Good day. on your second image, the most probable cause are dirty pressure roller under the drum. after cleaning, put it on the scanner glass and try to insert paper, if the paper you inserted, went deeper, you have to replace the roller. i don't know if our case is the same with regards to the spots, but in my case, it is due to power fluctuation resulting to power surge on supply of the print head.

[20gaugeO/U]

Re: RP 3700 dark/empty spots, thermal print head problem?

Agree with lambanogonline about cleaning or replacing the pressure roller under the drum if it's dog boned.

There may be a cut sliver of master under the master on the drum causing the white area on the duck head. Peel back the master on the drum and check the screen. If there are more slivers in the master making unit it could be causing the wrinkling also when it loads.

As for the dark areas run the checkerboard test pattern on Ledger paper and see what it looks like in that area. Strange shapes- sure there's not to shading happening on the original? Or colored original???

[slimslob]

Re: RP 3700 dark/empty spots, thermal print head problem?

First of all, I can't see your pictures just yet (thanks for including them though!).

The pictures in the attachments box at the end of the post would not open. The links imbedded with the text did.

[Iowatech]

Re: RP 3700 dark/empty spots, thermal print head problem?

The pictures in the attachments box at the end of the post would not open. The links imbedded with the text did.

That does work, thanks!
I agree with 20gaugeO/U about the light area in the duck head, that is probably a scrap of master material. Sometimes if you try to run a new master after the machine indicates that the master roll needs to be replaced without changing the roll that will happen.
The dark areas kind of look like the underside of the platen glass is dirty.
As far as the wrinkles in the master material goes, that's usually caused by there being the wrong amount of tension on the master material while the master is being made. Make sure the master roll flanges are in good shape and both of the flanges are properly installed, and I guess make sure the metal rollers in the master making area move up and down freely. There are a couple of master roll brakes that could cause the tension to be wrong if they have failed, but I can't remember ever seeing that on the Riso RP machines.

[risorp]

Re: RP 3700 dark/empty spots, thermal print head problem?

Thank you so much everyone, I've tried everything - reset/cleaning pressure roller but no luck. I gave up with huge frustration. but when i moved on the next job with new material, all the marks were gone. i found this thing that those dark blocks happens when the original image (which always goes on to scanner) have dotted pattern, like halftone pattern but very fine dots on grey area. Unfortunately, the white bit is still showing, i can even see it when i look at the master wrapped on the drum..still happy got out of those dark block issue! Thanks again for kind help.

[risorp]

Re: RP 3700 dark/empty spots, thermal print head problem?

Thank you so much everyone, I've tried everything - reset/cleaning pressure roller but no luck. I gave up with huge frustration. but when i moved on the next job with new material, all the marks were gone. i found this thing that those dark blocks happens when the original image (which always goes on to scanner) have dotted pattern, like halftone pattern but very fine dots on grey area. Unfortunately, the white bit is still showing, i can even see it when i look at the master wrapped on the drum..still happy got out of those dark block issue. Thanks again!

[jermyth]

Re: RP 3700 dark/empty spots, thermal print head problem?

That white spot sounds like something or some master under the master on top of the screen. Remove the master to that point and wipe that area clean, looking for the object causing the white spot and feeling to see if its a dent or tear in the screen or drum body.
Good luck.