GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

[filmplane]

I did a "deep clean" of a Federal Blue GR Drum and then installed a new screen. I am still having inking issues with this drum. I soaked the drum with the old screen on with mineral spirits (covered the drum screen with shop towels and dampened the towels with the mineral spirits). After the drum cleaning, I installed the new screen. I am still getting "blank areas" as shown in the picture below. Could it be that there is not yet enough ink flow in the drum yet? Should I keep running test prints or does it still appear to be clogged? Are there Test modes that ink a drum more heavily? Any advice or pointers would be greatly appreciated. Thanks!

IMG_2062 copy.jpg

[Iowatech]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

Is the ink bead OK? you should be able to see it when the ink bottle is out of the drum.

[filmplane]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

Is the ink bead OK? you should be able to see it when the ink bottle is out of the drum.

Not able to get a picture of it for you but when I shine a light in there, I do see beading on the rollers. When I compare it to my working Black drum, the Fed Blue seems "blotchier" if that makes sense, i.e. less consistent across where the rollers touch inside the drum. Hope that helps!

[DAG COPIERS & COMPUTERS]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

Try this: Disassemble the drum to access the ink distributor, remove it from unit and clean it with relevant solvent e.g kerosene, making sure that you blow the ink distributor with your breath.....yes with your breath while blocking one end with your fingertip. This should unblock any clogged hole. It's messy but that's what making money is all about. Reassemble the print cylinder, put back in machine and simulate Testmode 101.Then run many copies.

[20gaugeO/U]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

You can do what DAG said especially if your ink is really old, but as long as you have the shell off I'd clean the inside of the drum with solvent and wipe out. You could take off the screen and do it on the outside of the shell also. It does look like you have plugged holes rather than a poor ink bead

[filmplane]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

Try this: Disassemble the drum to access the ink distributor, remove it from unit and clean it with relevant solvent e.g kerosene, making sure that you blow the ink distributor with your breath.....yes with your breath while blocking one end with your fingertip. This should unblock any clogged hole. It's messy but that's what making money is all about. Reassemble the print cylinder, put back in machine and simulate Testmode 101.Then run many copies.

Yes, I think it certainly wouldn't hurt to do this with this drum. I am assuming that the Tech Manual should be the best guide for disassembly of the drum? And to clarify: are you saying I should run Testmode 101 when I test the drum after cleaning. Thanks for tips!

[filmplane]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

You can do what DAG said especially if your ink is really old, but as long as you have the shell off I'd clean the inside of the drum with solvent and wipe out. You could take off the screen and do it on the outside of the shell also. It does look like you have plugged holes rather than a poor ink bead

The ink I am using is not old but the drum may have been sitting for some time before I purchased it on eBay. I thought the solvent got all the holes unplugged but maybe not. A good clean inside and out will hopefully do the trick. Thanks for the tips!

[Iowatech]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

I only brought up the ink bead as if it isn't in good shape that could indicate that the squeegee roller drive belt has failed, or the squeegee roller one way is slipping in the drive pulley, or even the ink bead agitator (sorry, don't remember the actual designation of the thing at the moment, but there's a rod that rotates inside the ink bead to keep it as round as possible) is broken.
All of which I have seen cause the print defects that machine is showing. It's kind of why I never found cleaning the drum shell terribly productive. But that's just me.

[DAG COPIERS & COMPUTERS]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

Yes, I think it certainly wouldn't hurt to do this with this drum. I am assuming that the Tech Manual should be the best guide for disassembly of the drum? And to clarify: are you saying I should run Testmode 101 when I test the drum after cleaning. Thanks for tips!

Yes, the test mode 101 operates the ink pump allowing it to supply ink to especially a dry cylinder. Operate it after doing all necessary cleaning as advised by fellow techs. Having a manual at hand is helpful if you can get hold of one.

[filmplane]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

Yes, the test mode 101 operates the ink pump allowing it to supply ink to especially a dry cylinder. Operate it after doing all necessary cleaning as advised by fellow techs. Having a manual at hand is helpful if you can get hold of one.

Ok, wonderful. I appreciate the clarification. I am going to to do all the suggested cleaning that has been advised here in this thread and report back. I will try and document the steps with photographs as well for future Riso GR drum surgeons
Thanks to everyone who offered their expert advice!

[filmplane]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

UPDATE:

I have opened up the GR(w) drum and wanted to share two videos below. Does anything look problematic? I am not sure what the roller is called that sits between the doctor and squeegee roller, but the second video tries to get a view of it. Have no idea if it is how it should look or not. Also, the ink distributor appears to be distributing ink from what I can see after opening things up. Wondering if I should still clean squeegee unit/ ink distributor at this point or focus on the drum shell (inside and out) to try and remedy the blank spots?

1) The ink distributor view from inside the squeeqee unit section

2) the roller(?) that sits between the squeeqee roller and the doctor roller (sits just behind the squeegee roller in far back of video)

[filmplane]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

Successful deep clean!!! It was the drum shell: Super clogged with ink. Multiple rounds of towels soaked with mineral spirits on the outside of the drum shell AND inside, some toothbrush scrubs of the visible clog areas and a clean-up of the squeegee unit (excess ink) did the trick. Thanks for all the expert help and suggestions! Here is a video of the end result:

[Fayez Butts]

Re: GR(W) Drum Inking Issue, some blank spots are cleaning and new screen

Successful deep clean!!! It was the drum shell: Super clogged with ink. Multiple rounds of towels soaked with mineral spirits on the outside of the drum shell AND inside, some toothbrush scrubs of the visible clog areas and a clean-up of the squeegee unit (excess ink) did the trick. Thanks for all the expert help and suggestions! Here is a video of the end result:

Looks great! And now I've really got hope for some of the gnarlier drums I've bought off ebay