Help with Model 78 Linotype

[Les Stewart]

I am a linotype mechanic but have been out of the industry for many years. Recently I was asked to look at a model 78. Some years ago, it was dropped when moving and had to be rebuilt, but now I am looking at the machine and there are a number of things that are not right.

The main one at this stage the mould wheel and the pinion that turns it are too tight. Independently they both turn freely but when messed very hard to turn by hand. As the machine has not run for some time I am hesitant to power it up and run it through a cycle. I have a feeling that after it was rebuilt it has never worked. This is very disappointing as it could be a good machine.

Any help or advice on how-to proceed would be appreciated.

Les

[Mechanic]

Hi Les,

I assume you mean when you go to turn the mold disk, as you would when changing from one mold to another, as an operator would, the disk is hard to turn. If you pull disk forward it spins freely.

Unless the shaft that the pinion is on is bent or the ejector blades are binding against the back of the disk I have no idea.

When you are trying to turn the disk is the handle that controls the forward and backward movement of mold disk slide up and locked in position and the ejector link on and the lever pulled back?

I would take the main drive belt off and pull the clutch handle to engage the clutch and turn the machine over by hand. Initially the only thing happening is the mold disk turns to the casting position and first elevator descends to the vise cap.

You could shove a screwdriver under the first elevator to stop it descending and the only thing you are dealing with is the mold disk. If that feels okay I would try taking the machine through a complete cycle by hand.

[Mechanic]

Part two answer.

Thinking about your problem overnight, Les, I wondered if the guides that support the left-hand side of the mold disk, when the back knife is trimming the slug may need adjusting.

They should be adjusted so they just touch the front of the disk without impeding the turning of the disk. Sometimes the disk is warped from the pot being in contact with the disk for a prolonged period. So as you turn the disk it may be free in one spot and bind in another.

The lower guide also has the job of maintaining the mold slide in the correct relationship to the column. below the guide is a casehardened screw. This seldom needs to be adjusted, but if it has come loose or been turned by someone who didn't understand its purpose, it could possibly cause your problem.

To adjust this remove a mold from the disk. Turn the vacant position so that it is in front of the ejector. place a piece of paper between the lower edge of the slide and the column. Adjust the screw so that you can just pull the paper out.

In my previous post, when I said remove the main drive belt, I meant the flat belt that drives the rest of the machine.

I have never worked on English machines, all my experience is on US machines. Other than the magazine change I think they are the same.       

[Les Stewart]

Many thanks for the most helpful reply to my problem with the 78 Lino.

I will not be able to travel to see this machine for a week or so, but will take all your advice with me, (plus my tools)! So will be back in touch after that.

Many thanks once more, your advice is just what I need and confirms my diagnosis too.

Kind regards Les