The information in this section was pulled from a variety of sources by an AI agent. Once all recommendations have been confirmed or edited by MBP, this disclaimer will be removed.
The Hacker Poco Proof Press (typically the No. 0 model) features a cylinder with a standard cylinder undercut of .050 inches. This means the bare cylinder sits exactly .050“ below its bearers. [1]
To achieve a correct “kiss impression” on your flatbed cylinder press, the combined thickness of your draw sheet (tympan), packing paper, and the printing stock should equal the undercut plus an extra .002 to .003 inches for squeeze. [1, 2]
Your total packed height should sit right around .052 inches above the bare metal cylinder. Because individual paper calipers vary, always check your materials with a micrometer using this standard baseline layout: [1, 2]
Before locking in your packing, verify whether your press bed is adjusted for type-high (.918”) or galley-height (.968“). [9, 10]
Because you are switching between traditional type and photopolymer bases, the trick to a smooth workflow on your Hacker Poco is keeping your cylinder packing fixed while adjusting the height of your printing forms in the press bed.
To prevent having to rip out your cylinder packing every time you switch methods, you should establish a permanent type-high (.918“) standard on your cylinder. Here is how to manage both setups seamlessly:
Pack your cylinder exactly to .052 inches (your .050” undercut + .002“ squeeze). Use a hard packing recipe to accommodate both mediums beautifully:
Once this is clamped tight, leave it alone. Do not change it when swapping forms.
Because your press packing is now locked into a strict .918“ type-high expectation, you will manage your two different forms directly on the bed:
| Printing Medium | Bed Configuration | Adjustment Strategy |
| Traditional Lead & Wood Type | Galley Plate IN (.918” Bed Height) | Lock your type or wood blocks directly into the bed. Wood type can vary slightly due to age and humidity; use underlay tape or thin paper strips under low blocks rather than changing the cylinder packing. |
| Photopolymer Plates on a Base | Galley Plate IN (.918“ Bed Height) | Ensure your base is specifically a Standard Type-High Base (.858”). When paired with a standard .060“ photopolymer plate, the total height equals exactly .918”. |
Using a KF95 photopolymer plate on a custom base built to Standard Boxcar Base dimensions is an ideal setup. The math for your Hacker Poco press lines up perfectly with a universal type-high (.918“) bed workflow. [1, 2]
Because this combination meets the precise standard height of letterpress lead type (.918”), you will be able to lock up both forms seamlessly on your press bed. [2]
Keep the galley plate in your Poco bed for both configurations. [2]
Because both setups resolve to .918“, your cylinder packing can remain completely locked into your calculated .052” thickness setup. You will not need to alter your packing formula when shifting between antique type and modern photopolymer.