rollers?

im sure this has been asked a million times but i cant find the answer with the search. im sure there is not one answer either. i have a C&P 8x12 im getting set up. im a total newbie too. i will be running polymer plates for now until i can get some sets of lead type. the ink i have already is van sons rubber based. the rollers that came with my press are shot and the morgan trucks are corroded in place so i need a whole new roller setup, rollers, cores, and trucks. i have gathered that i need rubber rollers in lue of composition for my setup. i have heard several references to NA graphics and Ramco Rollers. as well as Advanced Roller Company, Finzer Roller and Pamarco Global. what would yall recommend for my setup?

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You can buy the replacement rubbers for the morgan trucks from NA Graphics, Ramco Roller is about the best price for rollers, you want the softest rubber rollers you can get, I use Roller Craft in Rhode Island for my ink rollers.

With photopolymer plates as opposed to metal forms, softer rollers can be a problem, as can Morgan trucks. (Morgan rubbers need to be replaced regularly, and if your tracks are worn, over-expansion of the trucks in compensation will just end up eccentric, which will result in the often-repeated distress calls on this list regarding uneven inking).
If you are trying to do quality work in PMS colors, get solid trucks the same diameter as your new rollers. Then you should adjust track height, using a roller gauge, to suit the form height. Note that your tracks will certainly be lower than a standard .918” form height, and that is where the contact between form and roller should be adjusted in the photopolymer era. Alas, most of the metal-era texts prefer truck adjustmen by Morgans, and track height is seldom mentioned.
Been there as I added photopolymer work, ruined a lot of jobs, learned better. It is a very delicate balance needed, and the old standard prescription of a 1/16” difference between truck and roller is very coarse by photopolymer use.

I presently do not have the rubber inserts available for the 8x12 or 10x15 Morgan trucks. I may get some in later this summer.

Morgan trucks were designed for the expansion/contraction problems of composition rollers that react with the weather and humidity. Metal type is so much more forgiving in inking than photopolymer, so we’ve seen a major shift to solid trucks as being a significant improvement over the Morgan truck. We started making the solid Delrin truck about 15 years ago and have sold several thousand of them since. They are reliably machined to be accurate. Old metal trucks wear to the point they typically are not concentric or uniform in diameter from one truck to another. The original trucks that came with C&Ps with the hollow inner ring are not turned from steel, but are cast iron. And the cast iron is what is called “Centrifugally cast” cast iron.

Photopolymer presents inking problems because of the lack of depth of the printing surface. Rollers have to be in good condition and set properly. Use of a roller setting gauge is essential, but the final setting of the rollers has to match the plate/base height. From our experience, most base/plate combinations are not precisely .918” but the setting gauge is very accurate. Use the gauge as a guide, primarily to set rollers to be parallel to the bed of the press, and then use some common sense to realize that the inking has to work with the plate/base combination and not the roller setting gauge.

Fritz/NA Graphics

Very well put, Fritz. Thanks for your input! I will then again probably settle for Delrin trucks.

Well I see the NA graph ones are 20-22 durometer in hardness. I think the Ramco ones were at 22-23 or so in hardness. Ramco also said softer rollers were giving them some inking problems with polymer plates, thats why they went up to the 22-23 in hardness area. So would the NA Graph rollers be too soft for using with my set-up?

A reading of 1 on the Shore Durometer scale is next to meaningless. Composition comes in around 16 or so, sometimes softer, rubber varies significantly depending on which formula of rubber sheeting is used and how long it is vulcanized, so a range is usually given, like the 20-22, or 22-23. Offset rollers typically start at Shore 28. We often see Vandercook rollers come in for recovering ranging from 30 to 65 on the scale, and in many cases, are still performing reasonably well but not where they should be. We have a Durometer scale and we check rollers that come in mainly out of curosity. Rollers will harden with age and repeated wash ups and the larger diameter rollers start swelling at the ends—all normal functions of age and use. Rollers exposed to UV light harden faster, and that includes sunlight and flourescent lighting.

Then there’s the Crisco factor. Today’s studio printers are afraid of all the volatile substances used for roller cleaning, and prefer greenwash methiods that just don’t work as well. Glaze and hardness are hastened. I’ve even found rancidity.