help w impression screws

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Hi all,
I have been researching and reading about the impression screws on platen presses (I am working on a Kelsey 5x8) and I’m having trouble interpreting some instructions for correctly adjusting the screws for a good impression. After a few days of fruitless tinkering, I am afraid I require some actual detailed advice on this. Could you please paraphrase or help me interpret the following quote (reprinted from Type & Press on the APA site):
“If one corner is too light, loosen the lock nut on that corner and turn the top one with a wrench in the same way as the lock nut was turned. That will increase the impression on that corner. If less impression is needed, turn adjusting nut opposite direction than the lock nut was turned.”
In the first sentence, I do not understand what the phrase “turn the top one” is referring to. If the M on the top corner is not coming through, what is the proper course of action?
I had been advised previously to just tinker and told that just tinkering would lead me to these conclusions on its own… but my tinkering seems to be going on too long and without any progress, even conceptually. Plus, my platen seems to be getting angry.
Could a friendly user or two please explain exactly how the lock nuts are to be adjusted to ensure proper pressure? And whether it is necessary or important that all 5 screws be somewhat in to the same degree?
Thank you so much and I apologize if this is an unreasonable query to be making.

Hi chopsockey, as think

Hi chopsockey, as think about it, I wouldn’t worry too much right now about the impression screws. Spray them up with WD40 or similar and leave them alone until you get your press up and going a little more.
Rarely did we adjust the impression screws. Once properly set they almost never required adjustment. When adjustment was needed, usually when printing solid, full form text and halftones, the upper screws might be equally tightened. Heavy die cutting, scoring, or perforating without rollers might need the same adjustment.
Don’t worry about the lower screws for now, and rarely was adjustment made left to right. When we finished printing the very heavy form we usually returned the screws to their former positions.
There were too many easier ways to adjust impression without having to mess with the screws. If you do adjust the screws mark them first with caulk or a Sharpie in a line with the lock nut and platen so you can return them to their former positions as necessary.
For the upper screws the lock nut is the hard part. A few sharp raps with a 16oz mechanics ball peen hammer on a short, stout, well fitting end wrench usually did the trick.
Hope this helps,

Thanks Dick… I will try

Thanks Dick… I will try that first.
I think i need better, longer wrenches as well. I am having a spot of trouble getting to the two on the bottom.

Hi chopsockey, C&Ps I worked

Hi chopsockey,
C&Ps I worked on usually had lock nuts on the impression screws that tighten against the platen. We would loosen the lock nut then adjust the impression screws. The final tightening of the lock nuts altered the impression slightly (generally lessened), so you learned to adjust for it.
For best results I would start by spaying a few times with WD40 and letting it set over night. Use long handled quality end wrenches.
Let us know how you do.

Achieving perfect impression

Achieving perfect impression (a relative term) upon a Kelsey is an elusive goal simply because of the unstable bed configuration. Unlike many other presses having solid bed to provide stable pressure, the Kelsey set-up can - and often does - allow some movement when under impression pressure. Slight to be sure, but on a large forme that is magnified as evidenced by slurring or fading colour, particularly at the extremities of the lock-up. Whenever possible, ensure your type set-up is centered in the chase, is locked solidly - preferably using metal furniture - and trucks/rollers are evenly matched. You can print a full form on a 5x8, but it does take particular attentions. Kelsey sold the detachable bed idea under guise of ‘ready-made’ stone surface. Factually, it was a manufacturing shortcut allowing less expensive casting/finishing process, thus more affordable purchase price. Some (raise your hand, author) have been moved to tack weld bed to frame. That doing, together with adding counterweight to arm support, transforms the Kelsey from boat anchor to printing press. And it does produce credible product. It ain’t a Pilot by any stretch, but heck, Japanese block printers employ common spoon in mating paper to block; witness that result.

Hello, Thank you both so

Thank you both so much for your feedback. I have followed the step by step instructions, and am getting pretty good (though still not exactly perfect) impressions. A tad more tinkering should probably do it…! Thanks again!!

I am assuming this would be

I am assuming this would be the same method of adjustment for a 8x12 C&P?

My only problem is that the impression screws wont turn… no matter what? Any suggestions for stubborn screws? I have tried a few things but am nervous about making things worse.

Alternately, is there anyone in the Chicago area who makes house calls? My press could use it’s annual check-up… (and perhaps you could adjust these testy screws for me?)

As FORME mentioned—-given

As FORME mentioned—-given was GOOD advice but…….
the CAP “M” and CAP “W” should be NEW or, at best,
used very little——and they should be 48-72 points for
best results………

1. Place new tympan on press

1. Place new tympan on press using 2 sheets of common paper as packing.
2. Lock a cap ‘M’ or ‘W’ in each corner of the chase. Ensure it is a solid lock-up.
3. Ink the press.
4. Loosen lock nuts on platen.
5. Back off screws until they no longer contact platen.
6. LIGHTLY turn screws clockwise until they JUST touch platen. (Use an ‘X’ sequence for balance.)
7. Tighten lock nuts.
8. Make impression on tympan.
9. Open press and observe impression for colour.
10. Should one corner show light impression, loosen that corner’s locknut then advance the screw one-sixteenth (or less) of a turn. Tighten locknut. Make another impression.
11. Should all corners show light impression, well, simply insert another sheet of packing to increase pressure. However, it’s better to tighten each corner screw (again using the ‘X’ approach) to achieve same density with minimum packing. DO NOT RUSH the adjustment procedure. It does take some tinkering to achieve result; but you will get there.