slugs sticking in mould

Someone was asking about slugs sticking in the mould of linotype/intertype machines.

Very early in my apprenticeship, I was told that a small quantity of zinc in the linotype metal could cause slugs to stick in the mould. Because we used some zinc etchings and zinc half-tones, we needed to be careful.

At the weekly newspaper where I worked, one Intertype had a 30 pica 7 point mould, and we needed to polish the working surface of the mould cap each week, or we would have a stoppage (at an inconvenient time) due to sticking of the slug. The mould cap had a part of the surface which looked to be rougher than it should be. I do not remember what we used as the polish nor do I remember if we tried cleaning the groove which cast the rib on the slug; years later, someone suggested clearing the rib groove with a piece of brass rule, but I do not remember the practical use of this.

One of the few things I disliked about the Intertype later models was the way the ejector blades in the box of blades could become disorientated, and need the services of the engineer to get them to be compatible again.


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re sticking slugs

P.S. the number of slugs produced each week using the 30 pica mould was small, less than 10% of the number of slugs from the other mould.


Yes, I remember as an apprentice, the operator had small can with graphite and a six-point reglet (about six or seven inches long). One of my duties was to dip the reglet in the graphite, then polish the top and bottom of the mold, to make ejection of the slug possible.
The same graphite I polished the spacebands with.
We had two saws: one for type metal, one for wood, zinc or magnesium plates! This kept the zinc out of our type metal.
Those were the days…

to all

Just been readng about maintenance of intertype (and some comment on linotype).

Here, on this forum, I will not identify the exact procedure about maintenance, it may frighten someone into trying to do the procedure (which needs some skill), and a mishap could “kill” the machine.

The maintenance item is listed to be done at certain intervals of time, but during a working life I never saw anyone attempt the item of maintenance. Yes, I know someone will ask what it was, so discussion may take place, but see first paragaph. Frustrating. When I wrote to a mechanic with the skills about the possibility of needing to do that job, I was cautioned to have replacement parts on hand before starting.

Other maintenance sometimes did not follow the recommended intervals of time, so apparently there are/were differences of opinion. My impression now is that some mechanics waited till the machine stopped, then lubricated or adjusted the part which complained.