Quadra Color has blue tint ,changed water form roller, reset ink forms ,good stripes 1/4" any idea
Ray...... you'll likely get many different ideas here, all will be valuable info. I haven't ran a QuadraColor in about 15 years but they have conventional ink/water systems that are pretty standard. Today's plates/chemistry usually runs very clean so since it's just one color it's likely not a "systemic" problem.
Personally, I think 1/4" stripe is pretty darn heavy. Our rule is 1/16" per inch of roller diameter, usually never going heavier than 3/16". My Heatset press has a Jumbo Form Roller that does both ink/water similar to the Quadstack and it's a 5.5"diameter and we still only set it to 3/16". If Ink Form Rollers are getting older/harder then it starts taking a LOT of pressure to make a 1/4" dent in the rubber to get that big of a stripe. Even rolls close to 30 durometer take a huge amount more pressure than a 22 to 25 duro. The harder the roller, the lighter the stripe needs to be (in my opinion) to prevent undue pressure at the contact points. The Ink Rolls need to lay the ink/water onto the plate, not push it into the plate. Heavy stripes also prevent the proper split of Ink/Water emulsion at the nip points of Plate to Form Roller and Form to Vibrator. Remember the Ink is holding over 40% of your water emulsion and needs to split properly or too much will stay put. An often overlooked setting is the Ink Form to Vibrator setting, again my opinion is the lighter the better. When I have a troubled unit that's giving me fits and I need to get a job out, I clean loosen the roller until it's not touching, clean it off and then slowly tighten it while inching the press and set it to just where it starts picking up ink from the Vibrator (or Oscillator, whatever you want to call it). Nearly 100% of the time this will get me a customer "OK" and I can get the job done with a clean plate until I get time to do a proper set. Ink/water emulsion seems to split and do it's job better when it's a fairly light setting at this point. Some operators run their presses with the Vibrator driving the Ink Form roller, I personally like my Plate to drive the Ink Form so I have a true contact with the plate. Most press Handbooks say to set slightly tighter to the Vibrator than the Plate, I like it the other way.... but that's me. In a perfect world they spin at the exact same speed but our presses are not perfect. If it's driving off the Vibrator then there is an ever so slight skid of the Form on the Plate and it causes wear, dot distortion and dirty printing. Different presses have different reactions so your mileage may vary on this one.
I know budgets are tight and not everyone can pull rollers when they start getting harder. Ideally Durometers for waters of 22 to 25 and inks from 25 in to coming out at 30 work best in my shop, harder than that and it takes a lot of pressure to make the stripe on the plate and you start getting clean up problems. I'd be interested to see the difference if you lightened ALL your settings on the blue unit to about half the size of stripes you have now, to the plate AND to the vibrator on both ink forms and the water form. Remember, only change ONE thing at a time or you don't know what fixed it. If your adjustments are worn or the Throw-Offs are loose it may not tolerate a super light setting without getting some ghosting in solids/halftones. There are many other things that can cause issues but if it's a general item like chemistry or etch that's out of whack, you'd see it on other units too. If you need a "cheat" to get by, if using an Acid etch your can add some Gum to the Fount. Gum is an excellent fugus food though, use with caution. Gum really only works on Acid so use caution if adding it to a Neutral or Alkaline. If it's hot in your pressroom, another cheat is to add about 10% Isopropyl Alcohol to the Fount. The addition of IPA not only lowers the surface tension of the water so you can more efficiently use less, the evaporative action of the IPA when the water hits the plate has a significant cooling effect and really helps when you have a hot or humid Pressroom. There's no hiding using Alcohol though, you'll smell it the moment you walk in the Pressroom so if your local DEQ or Fire Marshal frowns upon it, be prepared for a deduction in Brownie Points when they visit. My Inspectors show up about once a year and mark me down for using it every year but they don't tell me to stop, it's not illegal...... just frowned upon.
There are other things that can contribute, hopefully other will chime in with ideas other than rollers.
Keep us informed on how you progress......