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Funny Rail Height

Hi all,

I recently started working at a science museum in Springfield, MO, and we have a 10x15 C&P new style press that was being used as a static display. I decided to get it up and running for demonstrations and possibly letterpress classes, so I oiled it up and bought new rubber rollers and delrin trucks for it from NA Graphics, as the old rollers and trucks were missing.

Here’s a guest’s picture:
http://www.flickr.com/photos/dustinholmes/3637418812/sizes/l/in/photostr...

This press has an ink fountain and roller rails that go up to the fountain, alongside the inking disk. The rails alongside the chase are pieces of steel that have been screwed to the press with countersunk screws, and those pieces of steel are worn, but the screw heads have been brazed over on the right rail, so it would be tough to remove them, and that’s really the side with a few dips in it. ALSO the rails are below type high by about (as best as I can measure) about .070”. The rails up by the inking disk are about .040” below the face of the inking disk. What’s up with all that?

My first inclination is to flatten the rails down by the chase with JB Weld and stick a strip of thin sheet metal onto the surface with some good double sided tape, then fine tune it with some electrical tape on the trucks. I need to bring up the rail by the inking disk too, but by a smaller amount. How much is too much tape on the trucks? My guess is that .040” is too much.

Does anybody have any thoughts on why a press would have rails .070” below type high and .040” below the inking disk?

Thanks!
Brian Z

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On the ink disc check to be sure it doesn’t have a shim or other interference in its central bearing, and that the support bracket, which I believe is bolted to the bed, is correctly installed. But if the rails are that worn by the bed they’re probably just worn up at the disc too. The rail repair sounds like it was pretty amateurish — probably done by the printer, who was apparently not a machinist!

Bob

you may find the shim as mentioned by ad lib it will be there to keep the underside of the disc and its drive teeth in the right plane that being relative to the swinging pawl that pushes the disc around .
The bearer being 40 thou lower than your ink dsic would imply that your undercut is around that dimension on the ink roller /bearers (trucks) . some bearers are set parallel to the ink disc on some machines that are better built and the smaller less well constructed machine tend to guide the inker onto the disc while losing bearer contact in the cycle .

If the only obstacle to removing /replacing/re-machining the bearer rails, is brazed in bolt heads, it isnt rocket science to un-braze them (if further welding type operations are already being considered) un -brazing is virtually in essence no different to un-soldering electrical connections, just a little more heat, therfore un-braze/re machine to whatever requirement. Plus ink discs on different machines at different times have employed packing washers as A. height adjusters for obvious reasons, and B.variations of steel and brass/bronze or nylon washers to assist rotation plus as the rack,is usually an integral part of the ink disc the pawl and the stroke is invariably adjustable but doesnt always get matched when adjusting the ink disk and rails so perhaps further detective work before further adjustments to top rails perhaps???

Re-reading this thread I realized that a simple solution for the rails would be to drill out the screws that are brazed and any of the others that are stubborn, and replace the added stock with sufficient thickness to get up to type-high. But another way to repair it would be to remove the worn inserts and make adjustable rails from something like 1-1/2 inch wide 10-gauge steel angle cut in width on one web to match the rail width and screwed to the sides of the old rails — if there is clearance with the roller arms.

Bob

Interesting how the press was protected by the plexiglas enclosure. Nice safety treatment however if you start using the press on a regular basis you will want to get n there to oil it.
Steve

Yeah, I’m going to replace the screws holding the plexiglass to make them quickly removable. I like the idea of an adjustable rail made out of angle. That’s a really good idea. I would need to figure out how to make the curved piece of the rail higher to match, but I guess pretty close and with some tape would work. I’ll check that inking disk to see what’s going on behind it this evening when I go in. Thanks everybody!

Brian Z

O. K. So far with advice and proposed action. but why stop short for your top rails. Acquire your proposed material in lengths long enough to accomodate your bearers, and ink disk traverse in one (x2) lengths, attach the side arms as implied and then simply remove a “V” from the material side view on, bend it in a vice where the angle alters and by judicious use of a small file trim the “V” out till the 2 cut angles meet to give maximum stability and angle of approach, it will be so strong it will not need welding. Should it transpire that the angle at change of direction involves too quick a jump in one hit, it may need 2 or 3 smaller “v”s and slight contouring with hand file. This may also be apparent with just renewing original bearers with uncontoured steel, at original change of direction!!!Should the roller return springs be a little old and weary?

I got that press running today. I built up the low spots on the lower rails with tape, filed off the high spots (mostly where the bolts were not completely flush) and stuck on some .035” brass strips with double sided tape. I put two turns of electrical tape on the trucks. It seems to be working pretty well, but I haven’t printed anything outside the center of the chase. When I use a piece of Linotype as a gauge it just barely makes contact with the roller. I also built a treadle out of some wood I had on hand. It’s great to see this thing working after a lot of years sitting stagnant.