Paper will not drop down to gauge pins

I have begin fighting this problem for a long time on a\by 8x12 C&P. Start off the form and image is straight on page, but within a few sheets the stock will not go down to the gauge pins. The paper or card stock just seat where I place it.

I have the form locked up center top to bottom and side to side. The side gauge pin is just 1/2” up from the bottom pins. When the press is running I place the sheet as close to the pins before releasing.

But, the sheet never drops to the bottom pins.

I put on packing, antic-stat stray, and at times rubber baby power on the packing.

Nothing helps. The only way I can get all or 95% of the sheets to print completely is to is to turn off the motor and run the job by hand power.

I run the press at a slow speed to give me time to place the sheet.

And, when I think the problems is gone, I run about 50 sheets and find that 75% of not straight.

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Hi Aaron,
Why is your side gauge pin so low? And what are you using for your top sheet?

DGM

If you are hand feeding you have to push the sheet into he guides the sheet is not supposed to just fall into position.
Low side guide should not be the problem. I run sheets 20x28” on a Thomson with the side guide less than an inch from the front lay.

It just Tympan paper I purchased for 8x12 C&P press from NAgraphics. But, I see he doesn’t have the 8x12 size listed any more.

It not the oil Tympan paper listed, just die cut and scored sheets.

Would the oil Tympan paper work better.

I put the sheet close to the pins as the press starts to close. If not running fast, but at 68 years of age, it as fast as I can hand feed it.

The proper technique for feeding to gauge pins on a platen is to drop the sheet to the bottom pins and then slide it over gently to contact the side pin. This ensures the sheet is placed solidly to the bottom and guide side. If the sheet contacts the side guide before being firmly seated to the two bottom pins, it can hang up on the side pin and not sit firmly on both bottom gauge pins.

It is a two-step process, but can be done quickly and in a single motion of the hand. It does take practice, but can be done at a good speed. Feeding a press takes both hands as you will be pulling the previously-printed sheet from the press with the other hand while placing the sheet on the platen.

Static is the primary problem in most cases, but if the tympan paper is heavily oiled or a bit sticky, that can be an issue. Clean the top sheet well with type wash or other solvent, then dust with corn starch (baby powder is mostly starch), and the sheets should not stick to the tympan sheet.

Aaron’s placement of the pins is good for this technique, and leaves the side more open for whishing away the printed sheet without “catching” on the side gauge.

John Henry
Cedar Creek Press

Aaron,
When hand feeding you need to put the sheet into the guides exactly where you want it if register is important.
The sheet will not magically fall into the guides.
If unable to do it safely don’t do it.

John Henry,
You said it better.

Aaron, Are you running a feeder on this press and going back/forth, or hand feeding the entire time? Your language is a bit confusing but you don’t mention if you’ve got a kluge feeder on it or something.

It is possible that the tongues on the register pins are either too tight to the tympan and holding the sheet off the pin, or far too loose, allowing the sheet to “slouch” and curl under the tongue against the pin. Also, if you are not affixing the pins (with either sealing wax or a wad of tape) they may shift during the run, especially if feeding larger and heavier sheets.

I have not had this problem, but I offer the following feeding technique that I learned about 40 years ago:
On; Down and Over.

Place the stock on the open platen when it nears the flattest point in its cycle.
Slide the stock down the platen until the leading (gripper) edge makes contact with the gauge pins.
Using the tip of the middle finger, slide the stock over until it makes contact with the side gauge pin, being careful not to let the stock bounce off the pin.

Never aim for the corner between the gripper and side pins. On; Down and Over. I still repeat it to myself while feeding the press after all these years.

Sorry, I didn’t say it was on a C&P hand feed press.

I guess I should slow the press down so I can feed the sheet correctly.

Perhaps try just a tiny spray of Silicone Polish on the tympan, and the sheets will probably fly into the register pins like the proverbial *Rocket sledge on Rails*

Even if/when hand feeding just put a little negative curve to the stock to simulate Air Blast on an auto feeder, so that the *Head* tends to slide into the lower gauge with less friction.!

One more tiny gimmick which may have been lost! (possibly) for ease of picking up hand fed sheets, knock up, maybe ream at a time, prior to feeding, and with the knuckle of the big (middle finger) DESCRIBE, (dead centre, and gently) circles about 2” across, watch the stock fan out like seconds on a clock face,??