Baltimore Press Alignment Screws and Spring

We are printing on a restored Baltimore No. 12 tabletop platen press (6 x 4), which was purchased from an eBay seller in ready-to-print condition about two months ago. The pressure on the chase was level and printing beautifully when it first arrived but it ended up out of alignment after just some modest use. Now, no matter how many hours spent on aligning the impression screws and adjusting packing (including the recommended tympan/board/index/#20x4 stack), we just can’t manage to get a good impression (an example or two of what printing currently looks like below).

What’s wrong: With adjustments to the impression screws, the press will not maintain level pressure to print even impressions. Every time the alignment screws are moved to what should be level (either using a chase full of type, with a single piece of type in the four primary corners, or with Rick the Printer’s alignment magnets), the press will only print about the top ¼ to ⅓ of the image or text. The center bolt will also not work in adjusting the press, and its spring will not compress. In the original Baltimore manual (which we recovered via the Wayback Machine; happy to share if anyone wants it), it describes loosening the center bolt for adjustments to the four impression screws and then re-tightening the center bolt once alignment is complete. As it stands currently, if the center bolt is unscrewed at all, it separates from the press and pops out. Similarly, any attempts to screw it further in are fruitless: the bolt can be turned about one and a half times, but the spring will not compress at all.

Rollers are inking the type evenly, and as mentioned above, we are employing the recommended packing materials in the recommended proportions. The rollers are new. Type is levelled as best we can without an imposing stone (sorry, but we just don’t have one) and in any case the issues described here are afflicting us consistently regardless of the individual form.

What’s been done: The press has been adjusted using the method of placing a large piece of type (36 pt) in each of the four corners, and adjusting with the impression screws until each piece of type appears to print evenly. Once the chase is full of type, however, the alignment that appeared to work for the four corners will not work for the full form—the impression from the center and bottom is almost completely absent, though the type is evenly coated with ink—while the top is too heavily impressed. Additionally, with each impression taken, the alignment screws appear to unscrew themselves with the press motion—meaning that what could be “correct” alignment is almost impossible to maintain.

What else might we try to get back on track with printing? We love our little Baltimore, and want to see it used productively for many years to come! Thank you in advance for your suggestions and thoughts.

image: baltimpressions7may.jpg

baltimpressions7may.jpg

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How about lock nuts placed on the adjustment bolts threads (might be tricky to find the right threaded nuts) and then locking a start-off correct adjustment. Might need a thin or even a cranked spanner. Don’t over tighten.

Consider a longer center bolt and/or a shorter spring. Confirm that the threaded hole can take additional bolt threads (length), that is to say the hole is “not corroded’ to the point of stopping the bolt’s penetration into the platen. Your description reads as if the platen is rocking away from the form following contact with the top of the form. You believe the bolt is tight and locking the platen as designed, yet sadly… it is not.

Tom

T and T Press Restoration
www.tandtpressrestoration.com