Roller Rails

Hello all! I have recently taken my press apart to move and i figured since i have the bed off i would have the rails fixed because they are very uneven, as in dented in parts, and taping has become such a pain. I was going to take it to a local machine shop and have them mill them even and perhaps add some type of adjustable rail, I know there have been threads on this and have read some on them, but was just wondering if any one has actually has had a machinist do it before, and if anyone knows what the rail rail height would be in relation to the bed?


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Assuming the *Rails* have been found to be detatchable, (machine make/model would help Stateside armchair Tec,s) have your machinist, *Jig* them up as a pair, Milled off down to the lowest common denominator only, but keep in mind if you post the question What is the Ex factory height, records are probably skulking around somewhere.

You will get the mandatory spate of “They have to be type high”, which is not exactly gospel,? several machines employ and use Rollers that employ the compound at less than the diameter of the trucks, therefore the *Rail Height* does not always equate to type high, Every Adana ever made employs this syndrome.

Talk to “Tarheel Roller& Brayer Co. out of Clemmons N.C.” possibly.
Whatever the outcome for the eventual height achieved, request that it be down to the exact height to incorporate a Mild steel SLIPPER, to sit atop the Rails to come back up to the original Ex Factory height, e.g. metal at, 15 Gauge = .072 (thou) down to 25 Gauge = .020(thou) . .
Here U.K. as a matter of course, we now always fabricate Slipper,s to give .002” - .003” higher than standard, to give more clearance, we dispensed with *Taping The rails* back in the dark ages??? with .002” - .003” in hand, make ready and/or underlays are child,s play, acrylic sheet,s behind the image give a lot of leeway. plus OR minus.?

As you imply this has been posted before,!!!

When it comes to fashioning THE slipper a first grade metal work student would produce it as an apprentice piece,

Good Luck, Mick.

I would make them UNDER type high if I had a choice, if you intend to make them adjustable (at the lowest setting of adjustment, that is).
This could be useful if employing small wood engravings or cuts which you would rather not shim up to type high, as you could feasibly adjust the rails to block height in your case, and then simply add packing to facilitate desired contact/impression with the block.

One would think that keeping the packing behind the paper and not as an underlay beneath the plate would facilitate easier makeready, although I suspect there could be a lot of debate about this (especially when considering that a lot of people print mixed forms of different heights), but if you were solely editioning a wood engraving or metal cut, no other forms locked up with, you’d probably find not shimming beneath the block to be the best method of obtaining a solid, crisp impression IMHO.

I should think you wouldn’t want to be too far below type high, of course. How are you looking at making the mechanism adjustable? Rail covers and shims? Set screw/bolt/threaded assembly?

I was thinking along the line of a cover some sort that would attach with set screws and i need be i could shim behind it. I figured slightly under type high was a good starting point.

It is likely that the rails were originally type high or close to it, so if you get them machined so they are even, they are going to be under. So, you will automatically achieve what you are thinking to do.

To get an idea what the rail height is now, I would pick places on both sides of the bed, where the rails are as little worn as possible, then put a straight edge across, and then put a piece of type under the straight edge (if it will fit under), or alongside. You can then roughly estimate what the rail height is in relation to the type. Then I would pick the most worn place on each side and do the same thing. At least it would give you a rough idea what the situation is.

If the rails of your press are still taped, check the tape with a micrometer or caliper as you take it off, and this will also tell you what ball park you are in regarding how much you have to machine the rails.

I use electrical tape to tape the rails of my Pearl because the thickness of 3M electrical tape is stated on the packaging. Without going out to my shop, I think the standard tape is .006 inch and heavy duty is .0085 inch. (I only have to tape each whole rail because they are not uneven).

OK, I’m out of coffee at the computer so I’ll quit rambling now :)

After reading a number of comments like these I begin to think seriously that the small press makers (Kelsey, Adana, etc) deliberately jiggered the rail height/roller diameter/truck diameter combination to ensure slurring of inking, to make good quality printing more difficult for the hobbyists. It’s basic physics/geometry that if the roller and trucks are not very close to the same diameter, roller about .0625 or less larger than trucks, and bed rails are not type high, inking will not be optimal. There is too much variability among all these presses to be accidental and so few are correct. Wear is probably a factor but I don’t think it is the whole story.


Another possible explanation Bob, and I have run into this in the industry after spending many years in it: press builders are not printers, and I have had them tell me as much. They are machine builders. They don’t always understand the fine points of printing. In view of that, it is also possible that the design engineers and builders made the roller/rail/truck dimensions to what they thought would work best, but in the real world of putting ink on paper, it wasn’t the optimum.