color registration on kelsey tabletop platen

I’ve been a screen printer for years so I’m fairly fluent in registering colors for that process. i’m new to letterpress (and love it).

for the life of me, I can’t figure out how to achieve and maintain tight multi-color registration on my Kelsey 5x8 platen.

can anyone help a newb? i’ll be eternally grateful.

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What kind of gauge pins are you using? Are you using a consistent setup? The same two edges of the paper against the pins? Are the bottom two gauge pins far enough apart to keep the paper stable through the motion of printing. Are the gauge pins shifting? Being hit by the grippers?

Lots of variables to control. A photo or two could help. The Kelsey is not the finest press for close register work, but it can be done.

hey thanks for the quick response. depending on the run i’m using either kort or henry gauge pins. my main issue is getting the plate registered onto the boxcar base. I’m using photopolymer plates. is there an obvious thing i’m missing? or is it a “get it as close as possible and adjust” process?

One way to make adjustments might be to lock up your base with quoins on all four sides, ideally high speed quoins. Then when the second plate is mounted you can adjust its position in the press by tweaking the quoins to move the base. This means you will need quite a few “waste” pieces from each run to use to refine the register. This method makes it unnecessary to reposition the gauge pins, a process that messes up the tympan or the pins or both.

Also, are you getting register marks on your plates so you can mount them on the base to the grid?

Bob

i haven’t used registers as of yet, preferring to trim the plate to the artwork as much as possible but I use them for screen printing so I will definitely give that a try. thanks so much for your response.

love this site.

On a small press like a Kelsey, people are often using a base that is too large for the chase to put Quoins on all four sides. I also really never saw the use in that, either. I want my base to hold. still. in the chase and not flex- thus, Quoins on two sides only.
Not saying it’s a bad idea in all cases and for everyone, but I have to say some terrifically bad things could go wrong.

Anyhow, it seems you are having trouble with the plate mounting, not the registration of the paper/stock or register issues.

A tip I have is to use doublestick tape to mount the plate where you want it to be on the sheet.
Also, yes to register marks- and go get a chisel tip or broad tip sharpie, and be sure to color the tops of those with the sharpie so you can see exactly where it’s going, through the back of the plate, when you use them to place.
Insert your sheet with plate double-stick taped to it into your gauge pins, add some tape in the borders of the sheet so that it stays where it should while you’re closing the press, and close the press slowly to mount the plate to the base.
You should be able to get it where it needs to go if you’re careful enough.

good luck.

Oh, that assumes you’re using plastic backed plates, which it sounds like you are.

For me, it’s a case of get it close and adjust until it’s right. I use Megill Doublegrip gauges that are about as easy to adjust as the Korts. But I don’t use photopolymer and can’t help you much there. Make sure your base isn’t hitting your gauge pins and moving them.

As for quoins, the idea of opposing pairs is hard to do on a small press without a set of register quoins. Mine came in a set of 8…2 on each side. They look like small disks attached to a rectangular plate. Adjust them with a pin wrench in pairs. Loosen one and tighten it’s opposite. They are very thin (so they’re ideal for your small Kelsey) and can make very small adjustments to a base.

What I’ve done to get pretty good register between pp plates is to get crop marks around the outsides of the plates and then carefully cut by laying a straight-edge against the inside shoulder of the crops and cutting just to the edge of the art. If I cut all of them the same way, this technique gives me “frames” that fit very accurately to all the plates. I place my first plate and print from it, then carefully place a crop frame around the current plate. I peel the first plate off the base, then place the second plate inside the frame and finally remove the crop frame.

There’s usually still a little bit of tweaking to get really good register but this method works pretty well. I’ve used it to register back-to-front as well as multi-color.

Below is a link to a pic of what I mean. click through the album to the left to see a few more photos of what I mean.

https://flic.kr/p/oqgQmH

Michael Hurley
Titivilus Press
Memphis, TN

On some letterpresses, when you put the chase in, it doesn’t always go to the same place (in the side-to-side direction). When I put a chase in a C&P or a Golding, I am in the habit of always pushing the chase to the left as far as it will go, so it will be in the same place every time. I don’t know if that is also true of a Kelsey, but if it is, and you don’t always push the chase to the same side, that could be a cause of misregister.

thank you everyone so much! great feedback and techniques.

i heart briar press.

g