Correct roller/truck diameter for 12x18 C&P with modified rails
Hello all, I just recently purchased an Old Style Chandler & Price 12x18 press, and am in need of new rollers. My problem is, I need to figure out how best to make sure I have the correct roller height for the current press since it has been modified sometime in the past. I am going to buy a roller-gauge from Boxcar Press to help me get it adjusted properly, but need to figure out a few things before I order rollers.
1. The rails on the press have been “capped” at some point by a thin, roughly 1/8”, metal strip on the face that is screwed into the face of the rail. I do not know how worn down the original rails are, but some part do appear worn more than others.
2. The trucks and rollers on the press are NOT the same diameter, the rolls are quite a big bigger, which leads me to believe that perhaps the rails were raised too much with the repair strip, and so the rollers are bigger than they need to be OR the previous owner put smaller trucks on the normal size rollers!
3. What is (or where do I find) the original and correct diameter roller/trucks for a 12x18?
4. How in the heck am I going to get this thing to have the correct inking pressure, I will be using photopolymer plates so this is important. Would you recommend removing the metal strip (which I fear may be TOO thick) and using tape to build up/even out the rails? Or would using smalle/adjustable trucks be my best bet and keep the rail repair strips in place?
Any help would be greatly appreciated, I intend to be precise with my inking by using the roller gauge and setting everything properly, but I am afraid I do not know what size rollers/trucks would be best given that the rails are not correct, and I have no idea how to compare them to what they “should” be.
Thanks again,
Ben
Ben:
A good place to start is to put a good, straight edge across the rails horizontally, and run the roller setting gauge underneath the edge. If you don’t yet have the roller gauge, just take a piece of standard printing type or a plate mounted on the boxcar base under the straight edge to see if it aligns. If it doesn’t, you’ll know how much you need to adjust the rails to work properly.
Ideally, the trucks should be the same as the rollers or only slightly smaller to provide a bit of pressure as per your roller setting gauge reading.
i am going to use a straightedge as you suggested, but since I do not yet have the boxcar base or roller gauge, I cannot yet do that.
Also, does anyone know the ACTUAL diameters that the 12x18 trucks and rollers SHOULD be?
I checked the manual I have for the C&P Craftsman. It lists the rollers for the 12x18 at 2” diameter, and the trucks at 1 15/16” diameter.
I downloaded the manual from Boxcar press. When I looked on www.nagraph.com for rollers last time, Fritz didn’t have separate rollers listed for old/new/craftsman, so I think they are the same. You could call him and find out.
I don’t have experience with adjustable trucks, but people often have trouble getting them set correctly from what I read.
Keep in mind that the roller and truck diameters boundstaff gives are correct for the Craftsman, but that the Craftsman has rails that are type high. That’s why there is a 1/16” difference in their diameters: the rollers need to press into the form about 1/32” to transfer the ink properly. However, on most old style and new style C&P presses the rails are less than type high.
That’s probably at least one of the reasons that the rails on your press were built up. For the older presses it’s easier to buy rollers and trucks that are the same diameter, 2” in this case, and adjust the rails with tape or some other means to bring the rollers to the correct height. Here there may have been additional considerations as well such as worn or damaged rails, etc.
Note that even after building up the rails in the manner in which yours were done or with tape, once properly adjusted so the rollers are at the correct height they will still be below type high in order to allow for that 1/32”. That figure is a basic starting point, minor adjustments may needed to be made for certain forms. Boxcar bases seem to be particularly sensitive to roller height to produce the excellent results they’re known for.
So see if your modified rails are above, at, or slightly below typr high. If the rails are at or above type high, which from what you write may be the case, you’ll either need to use the kind of roller/truck setup they had or replace the add-on pieces they attached with thinner ones. Or you could do like most people, including yours truly, and just use tape. Others glue a strip of Formica to each rail which seems to be the correct thickness to get the rollers where they need to be. The ends of the strips can be filed down to transition with the original rails. If the original rails are wavy then then Formica may be the answer since tape would simply follow the contours.
Rich
Front Room Press
Milford, NJ
http://frontroompress.com
http://frontroompress.blogspot.com