Silvermaster plates, gum arabic and alcohol

[CostaRicaPrinter]

We run a couple of AB Dick 385's for book printing, one with a Kompac, the other with the super aquamatic alcohol system. With Silvermaster plates our problems are mostly with the plate drying out - we can't get enough water on them.

Since isopropyl alcohol is now kindly illegal in Costa Rica, folks on this forum assured me that ethanol will work with my AB Dick system, and they were right. It works great. One downside. It's expensive and I'm trying to reduce the alcohol. Acid solutions with glycerin do NOT work. We've finally accepted reality - in spite of gallons of the stuff on hand! Anchor (purple - can't remember the number) works the best, with alcohol.

This is my question: Are there any other wetting agents that I can use with my continuous, integrated system? Gum arabic? I tried some gum arabic, and didn't see any response, but it was in the middle of a run and everything was sort of contaminated. We also soften the ink a bit with linseed oil, which helps at least with paper lint (another factor in plate drying out).

Any suggestions welcome!

Bill

 

[RGPW17100]

Put a different dampening system on the press. Crestline or compaq. In the long run it will be your best choice. We used to have to maintain almost 25 percent alcohol with our super aqua.

 

[Lukew]

You have already been recommended a solution. Not sure if you gave it a trial. There are poly plate users on another forum that complained of the same issue. They were recommended the same products you were. Never bothered to trial it and are still posting with issues...
GENESIS WDP+HR
HABITAT UNIVERSAL FOUNTAIN SOLUTION.
ZERO ALCOHOL. ZERO ALCOHOL SUBSTITUTES.
Works with most solvent free inks, better still with the habitat ink.
I import this fount into my country to use as no other alcohol free fount would work without some issues.

If your not interested in trialing those products then perhaos import bmm2in1 fount in.. issue = costly. Stinks. High alc %.

 

[CostaRicaPrinter]

Luke - difficult for us to get fountain solutions into Costa Rica. Ministry of health has everything bogged down in red tape for any sort of chemical to get into the country. Glycol or any derivative counts as sufficiently deadly and poisonous as to require costly permits. I'd love to try all the founts that get recommended here - if only I could! But thanks for the tip. BG

 

[BillJ]

Gum Arabic is not a good choice. It tends to bond to the plate and cause blinding.

 

[Dan Roll]

To specifically address your question, gum Arabic is not a wetting agent in the strict sense of the term, although it is used in the beverage industry as an emulsifyer.
Try putting some of your mixed fountain solution in a sray bottle with a fine mister on it and spraying this into the press when it seems you can not get enough water to the plate. If this solves all your problems immediately, and they come back as soon as you stop spraying, you need a different dampening system. If this does not address your issues, there is something else happening.
I agree with RGPW17100, in that the most effective path to solving your issues is to junk the 'super aquamatic' and replace it with a different dampener (I like the Crestline, others disagree). Life is too short to spend it fighting a bad dampening system.

 

[CostaRicaPrinter]

Hi fellas - I've never seen a Crestline for the AB Dick 385's (although I have one on my 9840 and I love it - i'm with you Dan!), and Kompacs are a fortune. As I said at the beginning, with alcohol it works great, we're just trying to save some money buying less alcohol. The substitutes don't seem to work well in this system - I believe the problem is more to do with viscosity than "wetting" - the superaquamatic has a quite hard nip pressure, and seems to need a lot of viscosity to get through. That's why I was looking for something that would act like alcohol in raising viscosity. I thought maybe gum would do that. I've looked at fussing with the spring tension, but haven't figured anything out yet. Actually, the superaquamatic has some advantages - inexpensive roller that lasts forever, and a water pan that collects calcium and other stuff while the Kompacs can plug up (we also have a Kompac on another press; love it too, but there are disadvantages, especially the lack of a water pan!). We might just have to keep running our ethanol. We get very good results. I just wanted to know if any other "substance" would act like alcohol in raising viscosity, and maybe wetting better. Thanks everyone! BG

 

[Lukew]

Is it possible for you to get a hold of varn day international products in your region?
One possibility could be Varn alcofree. It is glycol based but is propylene glycol which is classified safer then the ethylene glycols.

I dont know of the dampening system your using but if you say there is a very tight nip high pressure between the dampening rollers then that poses a problem right there.
Is there a possibility to use softer shore A rollers in the dampening position with lighter springs?

The other thing I recall you saying is your adding linseed oil to your ink. Ink reps may correct me, but linseed is a natural drier. One would of thought if your adding linseed oil to an ink that already has a relative high drier load and possibly linseed oil already in the ink build the ink would / could possibly be drying up on the run.

 

[CostaRicaPrinter]

Hi Luke,

Thanks for the response. I can get Varn Total Chrome free. Maybe I could try that, with reduced alcohol. Good idea, I might try that out. Rubber rollers already pretty soft, but factory specs, not positive on the number. Linseed oil doesn't dry fast naturally, only with driers like cobalt, manganese, etc. I've notice an improvement with the linseed oil. Smooths out the ink and help combat the paper lint somewhat.

Thanks again!

BG

 

[Lukew]

No Varn total chrome free is designed for metal plates. You need to focus on fountain solutions that are designed to work with polyester plates.

 

[Tomtech]

Try an alcohol substitute. Your supply outfit should be able to get it for you. Since alcohol substitute doesn't evaporate quickly, it should help with the plate drying problem. Silver maters are prone to drying quickly. Kompac says you don't need alcohol in their system, but printers often use it to promote the ink drying on the paper. Good luck.

Tomtech