Hand Press tension help/advice
Hello, I wonder whether any Briarpress members with hand press experience can advise me about how to adjust the tension on my Washington press (20th century Reliance)? I was pulling an impression yesterday, and heard an unusual ‘clunking’ sound, and afterwards, trying to pull subsequent impressions the pressure had suddenly become much lighter, and the arm feels far less ‘heavy’ and moves more freely. I can see no cracks anywhere in the springs or arm mechanism, but a week or so ago the press was oiled for the first time since I acquired it (it had been sitting for a year or two in a warehouse unused before that) so I wonder if something has worked loose, or otherwise moved its position, and the press therefore needs to be readjusted to regain pressure? There are wheel nuts with holes to allow them to be unscrewed/screwed on the top of both springs as well as on the top of the platen, where the toggle mechanism meets it- should I try screwing/unscrewing these? Clockwise or anti-clockwise? Any help would be much appreciated!
It sounds like the platen return springs might have been hanging up, perhaps rusty, and the oil worked its way into the bearings and finally freed them up. I’m not sure what would make a “clunking sound” unless it was just the sudden slippage. I would see if someone can help you, pulling the bar through its full travel while you get close to the springs and their support brackets and watch the action and listen for any odd noises. Be sure the toggle is also well oiled, as well as the hinge pins of the bar and bar hook. Another place to check is the cup — if it had been stuck and suddenly dropped that could have contributed to the “clunk”.
Adjusting the spring tension of the platen support springs will affect the strength of the pull also — they just need to be tight enough to raise the platen to the stops on the undersides of the support brackets on the staple. Any tighter than that is a waste of the pressman’s energy. The nuts should be right-hand threads, so righty-tighty, lefty-loosey.
Bob
Thank-you Bob for your help! We managed to figure out the problem with the help of your detailed response, and some advice from Fred Voltmer (Havilah Press, CA). It was the cup that was the problem- the wedge was pretty far out to start with apparently (which explains why we had to use so much packing) and when it was oiled it slipped out even further, causing a sudden change of impression.