Lock-Up on two up Form

Hi Letterpress Friends,

Can I get feedback on this lock-up. I have not locked up number machines before, and I am no expert in lock up in general. Any key tips or techniques would be appreciated.

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You should never lock up numbering machines from end to end (or side to side) as you have in the picture, it will bind the numbers and make them difficult or impossible to turn, and possibly warp the frame of the numbering machine. Always lock them up from top to bottom. It is good to have furniture, and a quoin side to side, as it makes the form more stable, but I make sure the furniture only touches one end (or side) of the numbering machine.

When I used to number frequently this setup was very helpful. The length matched a furniture length and the multiple leads could be moved from side to side to move the numbering machine incrementally when needed. A two pt lead and a one pt lead combined with the machine creates the height so it can even be moved up or down by a point if you are numbering on a line.
Just remember to have the number machine parallel to the ink rollers = .

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Lots of problems with this lockup. All the printing elements seem to have pressure from one direction only, the type cuts from head and foot and the numbering machines only from the side. I would treat each pair of typecut and numbering machine as a unit, spacing them as Little Acorn describes above, in a composing stick to a common measure. Then the two units can be spaced apart with furniture and pressure can be applied from two directions, always toward the guide edges.
Next, furniture is better set wood against metal rather than metal against metal, less chance of slippage. I’d trade some of those slugs for reglet to place between metal surfaces, and move the wood furniture between the metal. That includes between quoins and chase.
Finally, hollow lead furniture should NEVER be placed smaller pieces against larger pieces without something more solid in between. The isolated pressure can collapse the wider piece. A piece of wood or metal furniture will distribute the pressure.
As Gilman says above, you need to lock up so the machine doesn’t bind. If you can’t push the plunger by hand (or by stick) it’s too tight. Sometimes it comes down to paper or card spacing.

Thank you all for the feedback, I’ll lock it up again and repost. I was told some poeple only lock up in one direction not two, is this a rule or a preference?

Numbering macines can be tricky little devils, If you are locking the machines parallel to your rollers, the rollers must just “Kiss” all the digits. too much roller pressure on the machine I have found will spin the the numbers out of sequence. Not enough pressure and you will not ink the lower height digits. There always seems to be a few, I try to run my machines at 90 deg to the rollers.
I hit against a latex sheet. My supplier at “Infinity Foils” call it “Tough Film” . .015” thick. it allows for some “give” so if a #3 for instance, is not the same height as a #4, it will compensate. Most often run int this with machines that have “Drop Zero” feature. Using machines that “Count Down”, allows for highest number to be at the bottom of the lift,
Watch for mis-feeds! You will want to make sure your press goes off impression if it misses a sheet. If you have to go back and hit a missed number, and numbers won’t turn as you like try using a wooden dowel or similar to push down the “No”, while adjusting the numbers.
I think this is most of what i have learned.
The machines are kind of delicate actually. Bring pressure up slowly so you don’t bend the center shaft.

Whoever told you that some people lock up in only one direction has no understanding of practical lockup, or they wouldn’t suggest such bad practice. Having just four elements in a form doesn’t change basic lockup needs. In fact, since numbering machines are not made to pica sizes, very precise lockup is critical here.
The material and lockup pressure on all four sides of a printing element are what keeps it vertical and in exact position. If only two sides are held in place, the element may shift during a run, and shift even more any time you loosen the quoins on the stone.
I didn’t want to get into inking issues, but I’m glad ericm did. It takes a soft roller to ink the number closest to the plunger, and used numbering machines may have uneven faces, especially drop-zero models. I like to get all the faces inked before I start the run too.

see photo
This is a form for numbering machines for a Meihle Vertical
Multiple machines can be used and positioned within the form
provides a secure proper lockup without binding the machines

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Good guidance here. I’ve actually cut a slot in the rollers for the No. plunger, so all the numbers would ink. Of course, you need to charge the customer for the replacement roller.