Ink Troubles

I am hoping someone can help me with my ongoing battle with ink trouble. Images are linked instead of attached.

Basically I never have solid inking and there’s always a fade in the print, just whether it’s super noticeable or not. In this case it’s such a small print area but the issue is dramatically visible. It will print ok for a few then you can see the ink will be gone in the very next print. And almost never evenly distributed.

Any help or thoughts on this is appreciated.

Considerations
•Press 1923 Golding Jobber No. 7 10x15
• Ink: Van Sons Rubber based mixing black and reflex blue.
• I skip feed everything for coverage has never been good. Assuming it’s all related.
• Temperature: 67-70 // Humidity 25%
• Paper: Lettra 220, but any paper I’ve tested has the same results
• Base: Elum with standard height. Alternated with Boxcar base. No difference.
• Rails: clean and tight. No Tape There are 3 bolts on each side that become loose and shift over time.
• Cleaning: I usually use kerosene and recently got some orderless mineral spirits
• Rollers, Trucks and Cores: all new

Log in to reply   10 replies so far

Have you checked the rollers with a guage to see if they are correct height. Hopefully you should have a 1/8 to 3/16 strip on a roller guage. Also what is being printed type or polymers?

Frank, thanks for your feedback.

Polymer, but type is also troublesome. But commercially I don’t set type, just plates.

I need to hunt down my roller gauge and see…

You may wish to do as the old printer did before he had a roller gauge.
Set as large type as you have across the breadth of the chase. Use a 1” strip of copy paper between the type and roller. Tug the paper strip. Do this in several locations. There should be just the slightest resistance to the tug. Ink up and repeat. The ink will provide about .001” less gap between the type and the roller. With your form at .918 and the rails at .918 your inking should be right. Normally on the old presses, the rails become worn and require some tape. If your rails are adjustable, you can bring them up to what you hope is .918. It is very difficult to measure rail height directly. Indirect measurement by measuring roller height does the job.

Thanks @inky.

Anybody have ideas if it’s not roller height?

If it is not a pressure issue or an issue with rollers/roller height….

next questions (for me)-
How many rollers are you running?

What is the temp like in your shop?

How old is your ink? (If rubber base, is it “tackier” than normal? If so, have you tried adding something to reduce tack and aid in transfer? Gans Ink, the company I buy my ink from, makes a ‘reducer’ which aids in transfer- added a drop at a time to a small pile of ink it can really help.)

I ask about ink tack because to me… This sounds like it could be a distribution problem.
I’m not sure I can help diagnose without being there, but a couple questions-

Where are you adding ink as your run continues, or is your press equipped with a duct/fountain? The ink disc can become starved in certain ‘patches’ that work their way around and get worse. Because it is a radial distribution system it can be kind of finicky, I’ve found.

I have found that how seldom/often I am adding ink can really affect the inking distribution with an ink disc style inking system- like on my C&P 10x15- if I don’t add ink often enough (mine has a fountain), it can have a cumulative effect where I have to throw the impression off and let the system run for a while to distribute the ink. The disc has trouble with patchiness, it’s not like an in-line system where the ‘slack’ is taken up more quickly.

Anyhow, maybe thinking about the inking system and doing some testing with that, if this sounds like it could be helpful.

Haven press: Great info! But I think thanks to the urgings of others, I have found the root of this evil is in roller height.

It does appear to be the rollers. Oddly enough and maybe it’s not that odd, but the readings are all over the place. Sometimes the gauge sneaks past the roller without even a trace of ink. Then if you roll it a little it will pick up ink. And from left to right it tends to read more towards the edges — That must mean something.

So where to go from here. To deduce?

Could you say and possibly determine the rails are worn in weird places?

Or the cores are wobbly slightly (though not old and were new to me a couple years ago.)

The rollers have never sat on anything for a period of time that would flatten them, but are they slightly off?

Could the trucks be slightly off in some way?

Or worse a little bit of everything?

You have progress. You have information. Now you must figure out how to use it.
Remove rollers and roll them one at a time on your stone or glass top coffee table. Have flashlight behind roller. Look to see if there are any spots where light shines through. Get a micrometer and measure truck diameter. You are looking to see if they are all the same diameter and if they mic round in several places. Did the rollers roll on the rubber or on the trucks?
Four hands work best for this next test. Lay the straightest straight edge you can find along the length of the rails one at a time. Inspect with flashlight behind. It is not unusual to find wavy wear in the rails.
These tests should give you additional information. Remedy can be challenging, but is doable.
Get some ink on your shirt.

appreciate it, Inky!

OK great-
(I hope my advice came off as helpful despite assuming less knowledge than you may already have, especially since I may have been barking up the wrong tree- but my heart is in the right place!)

There was another thread a bit ago where concentricity of trucks vs rollers etc was mentioned, and you’re onto something with the worn surfaces of the bearers as well- but I would submit that while these surfaces can be worn unevenly due to variable spring tensions as the rollers traverse up and down the bed; however, trucks and rollers- as mentioned in the other discussion- are usually not necessarily perfectly true/aligned with one another. I am unsure of the consistencies here, and there are only a few really reliable ways to actually inspect.

The practical advice is to either shim your base up a little (if your trucks are already riding straight on the bare surface of the rails), or use a bit less tape. If shimming the base, really doesn’t take much. A couple tissues behind the base makes a huge difference. You could tape them to the furniture behind the chase before lockup, lock the base up with the tissue in place, and then insert the chase into the press- no need to paste them in place or anything.
We of course tend to assume we should just barely have the inking rollers touching the surface of the plate, but you may have overcompensated and should add a little pressure?
If you do end up trying this- if you find the usual ink you add is slipping down over the edges of the plate in some places, it may be adding less ink could be helpful?

http://briarpress.org/46483

See JHenry’s post at the bottom of this thread, he describes the situation quite well.