Varying ‘open times’ between treadle platens

Has anyone compared the varying open times of different treadle platens?

I fell to wondering about this aspect of press design after recently reading that the Arab had been specifically designed to maximise open-time (as it was derived from other presses, presumably it was not the first to be designed with this feature). I had long been aware that early treadle platens such as the Alligator were notorious finger trappers due to short open-times, and had been aware that design changes over time had improved this aspect of operation.

In view of the variable speeds reflecting the vigour with which the operator tradles (or the differing speeds motors are set to), possibly the best basis of comparison would be percentage of the cyle that the press is open.

Some numeric data on this might make for potentially interesting comparisons between different presses, and could be a useful factor when choosing between presses.

I’d be interested in other forum members’ thoughts - and hopefully data.

Log in to reply   2 replies so far

The Hs Cropper and charlton machines opened wide with the platen tipping up almost flat in front of you ,similarly the chandler and price large platens did it .
The peerless machines are not so wide opening but are still manageable , the haddon swift is a true snapper -
narrow opening and quick to close , they open about half the distance of a typical adana .
Snappy machines tend to be in the region of 8”x5” or smaller ,bigger machines had room to incorporate the larger crank required to have wide opening in the operation , small compact machines meant less crank length so the cycles were quite quick .

The Cincinnati Type Foundry’s Nonpareil platen jobber has the platen mounted on long legs similar to the bed mounting of the C&P-Gordon presses and a mechanism tilts the platen to nearly horizontal as it opens. The amount of time available for feeding is pretty long, maybe 1/3 to 1/2 of the cycle, though the platen isn’t fully open that long. I’m VERY sorry I don’t still have my 10x15 Nonpareil so I could measure the open time. Another nice feature is that with the platen pivoting on long legs the impression is, like the C&P, nearly parallel. The press also has a wedge behind the bed for the throw-off, allowing inking up without inking the form. Nice press!