Dear Friends of TSB - I welcome your input and feed back to the calibration system instructions I have outlined. We will have this at Long Beach and we're doing a video of it next week.
How to use the NEW Leveling & Off Contact Calibration System
A discussion on calibration
For a screen printing machine to be in calibration requires that the three planes of concern are exactly parallel. The three places of concern are:
• Squeegee travel vector plane – this is the plane which the squeegee forms when it moves forward and back.
• Frame Plane – is determined by the exact positioning of the 4 corners of your screen.
• Pallet or Print Plane - is determined by the exact positioning of the 4 corners of your pallet.
If all three of the planes are not in planar agreement, the system is out of calibration. The result is a poor print quality.
LOCP System Summary of use:
Place a special pallet and frame on your machine. The pallet has shim plates magnetized on all 4 corners. The frame assembly has 4 knob stem assemblies to lock onto the pallet. Loosen the frame holders and allow the frame assembly to rest on the shims. Move the 4 clamps into position and tighten. Your off contact is determined by the thickness of the shims.
Lock the frame holders into position.
Repeat for each head.
Why is this Good? The New LOCP System reduces calibration time by as much as 80% and is extremely easy to use. It’s accurate on all 4 points immediately with no room for error. The most time consuming and difficult part of the process is setting the exact off-contact consistently. The new LOCP System allows this part to be done in literally one minute per head.
The LOCP System consists of the following:
• A Frame Assembly – Available in 23” x 31” & 25” x 36”
• A Pallet Assembly – Available in sizes compatible with above. 24” x 26” & 26” x 30”
• 16 Custom Steel Shim Plates – 4 each of 4 thicknesses – 1/16”, 1/8”, 3/16”, 1/4”. If more than ¼” off contact is required – the plates can be stacked.
• A 24” Flood Bar
o You Will Want – a Level. The length to be determined by your machine size. Big machine = big level
The LOCP System Frame & Pallet assembly is made using clear coat anodized Mic-6 precision ground aluminum. This material is known for its exceptional flatness. When investigating planar agreement it’s crucial to use materials of this quality levelness. Additionally – the LOC Pallet is 23” wide and allows us a greater area to calibrate with. This improves the precision of your calibration.
Calibration of a machine can be done in more than one way. Machines can be leveled from the ground up or from the top down. The LOCP System provides the tools needed to do it quickly either way.
When calibrating your automatic machine using The New LOCP System:
Setup the LOC Pallet - Determine your desired off-contact & place the appropriate shim plates on the pallet. Embedded magnets will hold the shim plates in position. If more than ¼” off-contact is desired – the plates can be stacked.
The Pallet is 26” long. When placed on the machine lock it to the position so that it will be centered under the screen.
For this explanation, we are going to discuss a top to down approach to leveling your machine. We will make certain the heads are all level. We’ll then calibrate pallets to the heads. We’ll then calibrate the screen holders to the pallet.
First – We investigate the squeegee vector ( aka Head Levelness )
• Place a Long Level on Head #1 – Determine levelness and repeat this process for all heads. If they are all level – great. If they are all slightly out of level, but by the same amount – great. If there is disagreement by a few heads – adjust those only.
• Be sure to understand your machines unique requirements to make these adjustments.
An Alternative way ( Ground Up ) – we can also use the LOCP pallet assembly to more precisely investigate the levelness of the heads ( squeegee vector )
• Place the 24” flood bar into the normal position of the squeegee carriage. Be certain that your flood bar is adjusted to be level. Air Cylinder stroke adjustments may be necessary.
• Rotate the pallet ( with shims ) to head #1 and lock it in place.
• Manually move the squeegee carriage forward and back over the pallet & Investigate clearance between the flood bar edge and the shim plates.
• Move the Flood bar to each other heads and repeat the process. This will provide a more precise understanding of all your heads levelness.
When leveling using the ground up approach – level pallet arm #1 and use it to calibrate the head levelness and the rest of the heads. Calibrate the pallet by any of several methods including a bubble level or a plumb to the ground. Be sure to examine all of the pallets before you pick one to calibrate the rest of the machine to. The first one you examine may be the worst of the pallet arms.
Next - we’ll investigate the planar agreement between the squeegee vector and the pallet. We will make adjustments to the pallet arm if the pallet is not in planar agreement with the squeegee vector.
Place the pallet on arm number 1 of the machine. (If your arms aren’t numbered – you should do this now. )
• At Head #1 – there should be no frame assembly or screen in the head.
• Put the 24” flood bar onto the normal flood position of the carriage.
• Rotate the LOC Pallet to head #1 and lock it in place.
• Manually move the squeegee carriage forward and back over the pallet & investigate clearance between the flood bar and shim plates.
• If the flood bar is not evenly clearing all 4 of the shim plates – then the pallet needs to be leveled. The LOCP System is machined to allow easy access to the areas of your arm that will require adjustment.
• Repeat the process with the pallet on arm #2 and then the rest of the arms.
Lastly – We’ll adjust the frame holders to be in planar agreement with the LOC pallet.
• Remove The Flood Bar from Head #1
• Place the LOCP System Frame Assembly into Head #1.
• Place the LOCP System Pallet on Arm #1
• Loosen the nuts that are used for leveling your screen holders until the Frame Assembly sits on the shims.
• Clamp the frame holder to the pallet using the sliding knob stem locks
• Tighten the frame holder adjustment nuts.
• Your head is now calibrated to an off-contact determined by the shims thickness
• Move the LOCP System Frame Assembly into the remainder of the heads and repeat the process using Arm# 1 with the LOCP System Pallet Assembly.
Leveling of all pallet arms can be done quickly at one time also. Loosen all leveling nuts on all arms at once. Move the pallet from arm to arm using Head #1 which has already been calibrated.
Conclusion – Once the process and manner of use are understood, the leveling and off-contact calibration can be accomplished in two hours or less.
