At the Mass Art Press (Massachusetts College of Art), we have two SP15s. Both have what seems to be significant lateral movement in the carriage. When the carriage is rolled beyond the feedboard over the bed, the carriage can be wiggled toward and away from the operator by…oh…lets say 24-36 pts.. I’m assuming this is not a feature of the press and can be adjusted/corrected, but how? I tried adjusting the large nuts at the base of the carriage and near the center on both sides of the press and this did not seem to have an effect, but I wasn’t able to get much leverage on them.
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G’day,
I know this is an old post but it’s new news to me. I was discussing lateral movement today. An engineer telling me ‘lateral movement? it’s just old mate, it’s wear and tear’. I’m not convinced. My press is a FAG TP550. I’m not sure how similar to the SP15 you were talking about here. My Fag is hand cranked with an adjustable bed (which is full of crud and doesn’t drop when adjusted (that’s another job on my list of things to do). Anyway my press has a groove on the impression roller sits on a rail as it travels across the bed (there are no side bearings to hold position). It runs across the bed smoothly. Fritz and others muted in another thread that this lateral movement could be normal. I’m thinking anything circular is going to have a limited tightness sitting in lateral groove. ie it’s just a guide. Any thoughts? It would be nice to know I can discount this movement if problems arise down the track. See pic attached.
thanks
Matt
KC
Well, you never did mention how this problem may be effecting the printing. If the presses are printing well, don’t fix them.
But yes, the cylinder carriage is going to be looser on off-impression.
Gerald
Thank you to all who have posted to this inquiry. I took in a printout of all the comments and reviewed them carefully with the presses. One key detail that I hadn’t focused on was that the movement I was seeing was OFF impression. While on impression, there was no movement. The issue may have been that there are problems with the trip lever (forever loosening screw connecting to the trip lever arms and the loose pin that governs their movement…under the feedboard). I may have thought I was ON impression when actually, I was not. Alas, problem “solved”! The description of the bed flange was also helpful. I was able to look at an SP20 at another shop that has much LESS movement off-impression and so I suspect our presses could be in better shape, but that the movement I’m seeing is not affecting impression too much. Should I try and tighten the press somehow to alleviate the carriage movement when OFF impression? Or should I leave well enough alone?
A video post would be great, but I’m not sure if this blog is set up for that or just photos. I had a series of 3 sent me for a Universal I problem that were a big help, and with the right equipment, the videos can be quite nicely done with good detail and resolution. Paul’s out of town this weekend, and maybe he can address this when he gets back. It’s one thing to speculate, it’s another to see the problem in action.
Ok, so here’s the next question: if the carriage can be wiggled as described, do the cylinder and carriage or sideplates move together? Or is there some play between them?
I’m just asking. It’s not like there’s an analytical flowchart to solve Vandercook problems. But considering the variations between models, and the way people have messed with their presses over the years, it can be hard to imagine from a distance how a given machine has gone awry, even on machines as simple as Vandercooks.
–Eric Holub, SF
Ok, Eric’s correct: the SP-15 doesn’t have a cylinder flange but has just the opposite–a bed flange that runs between the gear rack and the bed bearer and that rides in a groove milled into the cylinder casting, but serves the same purpose at a much lower manufacturing /assembly cost. With that intact, and I can’t imagine otherwise, the cylinder should have virtually no slop from one side of the press to the other.
It’s too easy to shoot off responses, and had I pried myself from the computer, the master carriage assembly print was about 15 feet from my desk, and a journey to the dark side of the shop would have shown me the same thing on our SP-15. The SP-15 prints have seen so much usage that they are starting to come apart. So I have undertaken having prints made from them for daily use, and I’ll stash the originals. It’s not cheap having large copies made, but we can’t afford to have the originals disintergrate.
So does the SP-15 have a flange?
There’s no lateral movement at all on my 325, with flanges integral to bed bearers, fitting into grooves between cylinder bearers and gears on both sides. On a No. 4, the flange is on the cylinder, fitting into gap between bed bearer and gear (is it just on op side or both?)
–Eric Holub, SF
As Gerald indicates, some movement is normal, and is present on the 2 SP-15s here in our shop. But I don’t see how the whole assembly could be moving so much. Pictures will be a big help, especially of the backside of the press. If as Eric points out, the tie rods are tight, and the cylinder flanges are intact and not broken, then there should be minimal movement and then this is a mystery.
KC
I’m not sure I follow this. There is a slack in the carriage i(forward and back) on my SP-15 of about 1/16 of an inch. And if I grab each cheek of the cylinder and twist it sideways I can move it about 1/8 of an inch. I’m hoping that is normal. I have seen many presses that are far more loose than that.
I watched a press mechanic check these movements for someone who was interested in buying a used press and I assumed he was checking for slack in the bearings but don’t really know.
I would think that if you have a damaged cylinder part that might be the first clue. If, as Eric mentions, the leaf spring is snapped (which I can’t quite see contributing to the slack) you want to get that repaired. This spring keeps the trip/print levers in their proper orientation, and your cylinder can just lock up during travel if it is damaged. And that, believe me, you don’t want to happen.
These springs (which as far as I know are used on most SP models) are a very poorly engineered mechanism and are easily broken by the practice of short rolling the press or halting the movement back and forth over the switching levers.
Gerald
Well, there iare leaf springs that affect the eccentric bearings, inside the side frames. Witjh a strong flashlight you may be able to see one. When the spring breaks, then the bearing will stay in one position. The manual (available form NA if you don’t already have it, along with the springs) has a page showing the spring and how to replace it. The manual says to chisel off the stub of the spring, but a Linotype matrix hook pulls the stub off quite easily; it’s just a 1/16″ x 1/4″ x 18″ steel strip with a hook cut into the end.
In addition to a flashlight, a dental mirror can be helpful figuring out what is going on inside the side frames.
Eric Holub, SF
As I recall, what is referred to as the eccentric (with which I’m not all that familiar) on the far side of the carriage is damaged and may account for the movement. I don’t know exactly to what extent it is damaged, and what is entailed in the remedy, but I will photograph and perhaps make a quick video with my camera of the “wiggle” and I’ll test it as you’ve described. Thank you for the detailed response. KC
What you describe is very curious. Many Vandercooks have a flange between the bearer and the gear that prevents any lateral movement, but from the muddy pictures I have, I can’t tell what the arrangement is on the SP-15.
If the cross-rods are holding the sideplates together, and the eccentric bearings are firmly attached to the side plates, and the cylinder shaft goes through the eccentric bearing, where can there be 1/2″ of slack? I wonder if the cylinder carriage is otherwise functioning normally: does it go on and off impression as it should (on both ends of the cylinder), does it move the full length of travel. And when on impression, do the roller bearings have a snug contact to the rail above? That’s the quick test of their setting, whether they can be turned with your finger. I think they should turn with a little resistance, and all definitely should feel the same.
–Eric Holub, SF
I do, in fact, mean laterally from operator side to far side. I’m not sure how to measure the play in the other direction. I can actually wiggle the carriage…meaning, the play is not directly back and forth across the lateral direction…I will read the article referenced above and return if I still have questions. Thank you very much and hooray for this blog!!!!!!!!
To me “lateral” would mean across the bed, or from operator side to far side, and it is hard to imagine that developing unless the carriage cross-ties were loosened.
Or are you referring to play between the bed and cylinder gears when direction of cylinder travel is reversed? A small amount is normal and necessary (I have 1/16″ play) and nothing to worry about. A half-inch on the other hand is strange. Inconcievable actually unless gear-teeth were missing or not meshing. Can you elaborate? Does the cylinder move smoothly and rotate from trip to print normally?
In any event it is NOT a good idea to mess with adjustment of carriage bearings unless you are sure what you are doing. The carriage rides on the bearings when off impression, and holds the bed and cylinder bearers in contact when on impression. Misadjustment could throw carriage off level or lead to excessive wear.
–Eric Holub, SF
Anyone contemplating this repair should first read Gerald Lange’s article “Adjusting Cylinder Carriage Bearings” which can be found on this website at https://vandercookpress.info/articles.html