Troubleshooting the press


Anyone know of any left-hand threads on any press? I know of one on the Linotype.


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Half of every impression bolt on a Gordon platen (so every C&P). These are hermaphroditic, left and right on either end.
What is left-handed on a Linotype?

the operator.

re left-hand

Thank you to parallel imp for the word hermaphroditic; of course this kind of thread(s) is important on a press.

What I was referring to is what can be a trap for young players and newbies. To explain, a friend had a Chrysler automobile, with a slow leak in one tyre (tire). One day he came to me, quite flustered, and asked (knowing that I had also had a Chrysler previously) if there is a trick to undoing the wheel nuts; the reply was that on some models, some of the wheel nuts are left-hand. Enlightenment! Those on one side are left-hand, the other side is right-hand.
And, of course, there was vehicle where the hubs had been swapped side-to-side, which was fairly quickly diagnosed.

I had hoped that someone else would write about the left-hand thread on the Linotype; they would be able to give a clearer description than I usually do. Most Linos are equipped with a 4-mould disc, or a similar mouldwheel with two pockets; a few have six-mould discs, but that I put aside, although it’s still much the same situation. The drive to the mould disc originates in two sectors of gear mounted so that the first action is a quarter-turn while the first elevator descends; the line is cast, and (usually) the mould makes a three-quarter turn to the position for ejecting the slug.

To change from one mould to another, the operator (seated normally) reaches over with his left hand and pulls towards him a knob on the end of a shaft, which disengages the drive and enables the mouldwheel to be turned freely. Releasing the knobbed shaft, it springs back and a pin between two parts of the shaft locks them together when the knob is wriggled. This pin is threaded into the part of the shaft by a left-hand thread.

One of our Intertypes was fitted with mouldwheel-turning segments so that each of the two movements were a quarter-turn only so that two moulds were in operation; this was to counteract cooling problems during high-speed operation. To get the last slug out, a blank was cast in the other mould. I wished that our Elektron had had two-mould operation, but that could have led to complications; besides, we needed all four moulds to be of different sizes.

I have heard many stories about problems with left-hand threads (on other machinery) when the person working on the machine was not aware that they were there. I wondered if anyone had seen them on any press.