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* 인쇄에 도움이 될 듯해서 올립니다. 영어로 되어 있어서 좀 그런데 완전 번역해서 올려주시는 분께는 제가 소주 한잔 뫼시겠습니다. Q: I have had trouble with my automatic press not making consistent prints from pallet to pallet. I've tried adjusting the pressure on my squeegees and flood bars as well as using coarser meshes in my screen, but nothing seems to help. A: You are not alone; I hear of this problem on a fairly consistent basis. A typical solution is to add flood bar and squeegee pressure, which you have tried. Although this may help increase ink coverage, it won't solve inconsistent printing from pallet to pallet, as you have discovered. First, I must make some assumptions about your screens. The type of mesh you're using won't make much difference in this scenario, but consistent tension from frame to frame is a must. You may think that your automatic press is out of mechanical registration. While this could be the case, in all likelihood the press just needs to be leveled or zeroed out. If the press is not level, consistent print quality is sacrificed - from ink deposit consistency to registration accuracy. You may not have experienced registration problems except with critical registration jobs. As process printers know, leveling the press is a very important part of prepress to ensure consistent printing from beginning to end as well as from pallet to pallet. If your pallets or heads are out of level or plane, the color difference and registration on a process print from one pallet to another can be astonishing. The leveling or zeroing of the automatic press is simple if you do it on a regular basis. The first thing you need to do is to get the print heads in a level plane from inside, or center, to outside. Using a typical carpenter's level, adjust the print head arms so they are level. Most automatic presses allow for some type of adjustment of the overall head, either from the feet on the stanchions or sometimes in the gussets which support the heads. This part is not as critical as the pallets and the off-contact in the screen clamps, but it will guarantee consistent flood and squeegee pressure from the front to back during the print stroke. Tool-less leveling once the heads are level, you can begin leveling pallets. There are a few different techniques for this. The first one uses a typical flood bar (see the illustration below). Let's go through the process step by step. Step 1: Place a flat, straight flood bar into its standard position on the press. Step 2: Using angle and pressure adjustment, adjust the flood bar to an upright position so it just kisses the back of the pallet while locked into print position. Step 3: Set a carpenter's level on the flood bar to ensure consistency. Step 4: Release the air or mechanicals so the flood stroke moves freely by hand. With the pallet locked in print position, drag the flood bar back and forth across the pallet. Step 5: Adjust the corners of the pallet so that the pallet barely touches the flood bar as it passes over. Step 6: Repeat the process for each pallet. This gets the pallets lined up in the same plane and level. To set head screen-clamping and off-contact distance, simply use the No. 1 pallet in each head. Place quarters or washers on each corner of the pallet and lock into print position. With a meshed screen locked into place, adjust the off-contact in each corner so the mesh just touches the quarters or washers in each corner. Repeat these steps for the remaining heads using pallet No. 1. Four-point leveling of the pallet is important. Using a flood bar and washers to level the pallets and off-contact is the least expensive way to get your press level. Off-contact gauge there are better leveling methods for more consistent results, but they require tools. One such tool is an off-contact gauge, which is something like a dial indicator creatively attached to a carpenter's level. To use it, choose a pre-leveled head and place a mesh-free
