Throw Off Lever getting tight

Lubrication is always good, but you most likely have a misalignment problem. Get behind the press and either with your long arms, or an assistant, operate the throw off lever to see what it does and what moves. There are three shafts with parts connected one to each shaft that move thru an arc when the lever is operated. The top one is the larger diameter (and usually bare, unpainted steel one) to which the roller arms are attached. A link attaches to the fixture on that shaft and connects to a fitting on the next shaft down. That piece on the middle shaft has an internal cam mated to the piece on the bottom shaft. Most likely one of those fittings on the middle or bottom shaft have become loose from its shaft and has moved a bit and caused misalignment. Disconnect the link between the top and middle shafts. Operate the lever. If difficult, the misalignment is between the fittings on the bottom two shafts. If the lever moves easily with the link disconnected, report back and we will investigate further.

I am having the same issue with my C&P. I followed the instructions that inky suggested only to find that the lever moves effortlessly while the back throw of connection is disabled. What else could the problem be? How can this be fixed?

Thanks!

There are three problems I’ve encountered before in this area:

There are two locking collars on each of the throw off mechanism shafts, one at either end on the inside of the main frame sides. These keep the shafts from sliding out of the frame but the castings are not machined on their exterior surfaces and so can be a bit uneven. If they are too tight against the frame sides when secured they may bind when the shafts revolves. So you might try loosing the collars, sliding in a piece of index card as a temporary spacing guide, and then securing the collars again. This will give them a bit more play while allowing them to perform their function.

Another problem I’ve had is excessive dirt and especially ink that has dripped and accumulated where the two parts of the throw off mechanism on the shafts meet. The one has a pin and the other a slot for the pin. Not only does this gunk gather in the slot but the two flat meeting surfaces are machined, not painted, and are therefore sometimes rusty. You can try to clean in between with WD40, rags, etc. but meeting an easier way to get access between them is to loosed the four shaft collars and slide one shaft one way and the other the opposite direction. Then you can get right into the slot and get to the flat surfaces and clean everything thoroughly. You’ll need to disconnect the throw off lever to do this.

Finally, even if the above things are OK, the large eccentric shaft at the top of the bed casting where the arms connect has two locking collars on the inside where the shaft goes through the casting to prevent the shaft moving left or right. Just as in the first issue above, the collars may be too tight against the casting and make make it hard for the large shaft to revolve. It only moves a little bit but it was enough on the last press I restored to cause the problem you’re describing. Once I allowed slightly more play in the collars, things worked fine.

Rich

Front Room Press
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