uneven ink distribution = roller slur

I’m printing on a Vandercook SP-15 that doesn’t have an electric motor, so ink distribution is being done manually (with a crank).

As you can tell by the picture, my rollers aren’t inking properly from the back roller to the front. The back roller on the right side is too high—so high that it won’t even register with a roller height gauge. However, the cog (on the right side—back) is engaged, preventing the roller from lowering any further. So I inked up the back roller to see how it was distributing. This was the result.

Any thoughts or suggestions would be greatly appreciated!

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Oops—here’s the picture!

image: DSC_0021.jpg

DSC_0021.jpg

It almost looks as if the front roller is too high and is preventing the distribution drum from spreading ink onto the back roller. If you are using a gauge and the back roller won’t lower enough to register on the gauge something is wrong. Look carefully to see if something is preventing the back roller from lowering as far as it should. The cog shouldn’t get in the way of this.

this is a manual press… there is no distribution drum in the press. also, we are using a roller height gauge. the rollers register properly on the front roller and on the rear roller on the left side (near side). it’s only the back roller on the far side that’s too high. it’s so high that it doesn’t even touch the gauge. there is a cog attached to the rear roller (see image) that seems to be preventing that side of the roller from lowering any further. the cog is engaged with the track along the side of the press bed. so you’re right… something is wrong. we just can’t figure out what. thanks!

Is the cog ( I assume you the mean the gear on the side of the roller) maybe hitting the bed rail? That would prevent the roller from lowering all the way on that side, but the roller might still turn as it travels down the bed.

But … if the roller isn’t picking up ink from the vibrating roller (what I called the distribution roller) it still seems to me that it is too low, at least in relation to the front roller. If it were too high on that side wouldn’t it pick up ink on the rear roller but not the front?

Do you know the age of the rollers? It may be that they have shrunk over time. The diameter should be 2.5”. If significantly less then you will need to have the cores recovered.

The gear bottoms out on the rack thus preventing that side from lowering as much as the operator’s side and the front roller.

Your rollers are probably undersize. It isn’t such an issue for the front roller, but the rear roller must work with the gear.
As a quick-and-dirty fix, I have taken off the gear rack and removed the shims underneath, allowing a slightly lower roller adjustment. But a new roller the proper diameter is better. I don’t recall the correct size, but it will not be to eighths or sixteenths on Vandercooks; instead it will be to the half or whole inch.

Thanks to all for your responses. I think the roller is dead and a new one is necessary. It appears to be in good shape, not cracked or misshapen, but it definitely looks too small.

Thanks!
Amy

Eric

Truth be told, and, actually, don’t you think it should be?, allowable tolerance is not “to the half or whole inch.” Nor is it “eighths or sixteenths.”

Gerald

OK, let me put it another way: if Vandercook rollers are measured and the existing diameter includes a fraction less than 1/2”, then round up to the nearest half inch to find the original diameter. (Or round down if the rollers are oversize rather than undersize.) Are you aware of any common Vandercook rollers that were made to a diameter that ended in sixteenths or eighths (or even quarters)?
Since you rightly bring up tolerances, yes, Vandercook rollers that include a gear do indeed have narrow tolerances. They aren’t like other presses that allow for rollers to be reground and reset. The one time I was dealing with an SP-15 with this problem, I think the roller was about 1/16” undersize. That’d sit only 1/32” further away from the .918” plane. right? That’s why removing a few shims, maybe 20 thousandths, worked as a very temporary solution.

It occurs to me that the tight tolerances may be more important in the later Vandercooks using fine-tooth roller gears such as the SPs and Universals. The teeth are shallow, and allow for a narrow range of adjustment.
But older models use a coarser, deeper gear tooth. It might be that a press like my 325 or an OS 219 would allow for lower roller adjustment before bottoming out in the gear rack. It’d be nice if I could regrind my 3” rollers, but that’s not possible with SP-15 rollers.