C&P 8x12 binding in part of cycle
Hi all,
I am working on getting my new C&P 8x12 treadle (1911 model) up and running. Thanks to all the information here, I’ve got all oil holes and metal joints cleaned and moving.
The problem is that the press moves very easily for about 3/4 of a cycle, then binds for about 1/4, when the platen is almost all the way open, until it starts to close. I can move it through the cycle with the flywheel (takes both hands), or if I treadle hard, I can keep it going. This doesn’t seem right (I’ve read that it should move easily on it’s own for at least a full cycle).
I’ve done lots of “press yoga”, sitting under it with a flashlight and turning it over slowly. The race in the large gear cam wheel is clear and oiled, as is the cam roller. There are no metal shavings here, and it doesn’t look like the cam roller is rubbing the side of the gear.
The binding happens with or without the treadle attached, and with or without the throwoff engaged. I do not have rollers on.
I cannot see the pinion gear well, as there is a home-fabricated guard over it and over the large gear. (I’m tempted to cut it off to improve cleaning access and see better what is going on). The press is still filthy outside the oil points, and I will continue to clean, but this binding seems to be too hard to just be debris.
Any clues? Anyone in the San Diego area who works on C&P’s for pizza, beer or cold cash?
Thanks,
Susie
I’d listen very closely for any sounds of binding. A mechanic’s stethoscope might help.
The binding frequency seems synchronous with the rotation of the mainshaft, so I don’t think the pinion gear or crankshaft are an issue.
I’d flood all the oil ports indicated in the chart found here on BP, particularly those related to the platen closing and the rocker (the rocker ports are easy to miss and can take a lot of oil).
I wouldn’t treadle or run it any more than to investigate the source of the binding, rolling the press forward and back to the point of binding to see if it works oil into any dry areas. If it doesn’t seem to loosen up, it may be time to take parts off in a process of elimination.
For comparison, the 10x15 I work on will roll freely for about 6 cycles when given a good tug on a flywheel spoke.
Regards,
AM
Sounds like the binding is part of the rocker action, driven by the main gear. The pinion gear and crankshaft turn many times for one revolution of the main gear, but the binding is limited to a specific section of the main gear.
First I’d see if the main gear and the pinion gear stay perfectly aligned through the cycles. Any sign the main gear is wobbling? Then I’d check the rocker arm for similar variations.
Without disassembly, you don’t now what previous owners have done or neglected in over a century. My first platen jobber had been shimmed in the bearings of the platen and the timing of the rocker arm to the platen had been changed.
Thank you, AnonyMouse and parallel_imp, this is helpful. I will check all these things, and let you know what happens. Who knows what this press has been through…
Cheers,
Susie