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Looking for SPM Calibration Procedure for setting the Z-Axis ?

Micheal

#33263

Looking for SPM Calibration Procedure for setting the Z-Axis ? | 17 March, 2005

I am looking for the Procedure to Calibrate the Z-axis gears (blades) on a MPM SPM Screen Printer. Does anyone have it, I would appreciate it.

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pmd

#33287

Looking for SPM Calibration Procedure for setting the Z-Axis ? | 18 March, 2005

Please clarify, Z axis gears (Blades)? The MPM head I believe is what your are asking is driven up and down via a lead screw. The machine gets the zero point from the "HAT" tactile sensor in the table nest. When squegees are installed the blades are leveled and stencle height mesured useing the tactile sensor. This determins the Z height. The zero point is another sensor on the head when the machine is initalized. Each has it's own calibration procedure. If the head sensors have not been removed or adjusted then you probably do not need to worry about this. The Hat however will sometimes come out of adjustment. I cant off hand remember what this setting is but i think it's either 6 or 6.5 inches when hat is extended and is set useing allen wrench to the setting just when switch closes. If the setting is close then when some mesurable snap off is set and board loaded to stencle level the same distance should be seen between the board and stencle given the board thickness setting is correct. Now if paste is not wiped clean when print cycle is complete and board is close to stencle then you may need to set a little more "down stop" in your setup menu for each blade. The blade must go into "Float". You can see this by removing the cover on the head. If you notice when you lift by hand the part of the head that moves it has a travel between stop blocks of about an inch. The down stop setting continues to move the head down after it contacts the stencle by the amount set, the blades will flex untill pressure setting is overcome. Only then will the head go into float. If you dont have enough down stop the head will never go into float and no matter what pressure setting you have set the pressure will not transfer to the blades because it is stoped by the limet blocks. There is really no way to have too much down stop unless the top stop blocks are contacted. So if paste is not wiping clean then try putting .15 in in this setting. WARNING! if blade pressures are set above default of 1 lb. per inch of length of blade then you may rip the stencle from the frame or otherwise damage the stencle.

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valuems

#33289

Looking for SPM Calibration Procedure for setting the Z-Axis ? | 18 March, 2005

Hello Micheal We are looking for the procedure at this time. And there is no tactile sensor on any SPM made by MPM. The SPM's does not have sensor's on the head either. Any way we will send the procedures and the calibration blocks soon. harry

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pmd

#33290

Looking for SPM Calibration Procedure for setting the Z-Axis ? | 18 March, 2005

Sorry I was not familiar with the SPM machine, Disreguard previous response that I sent.

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valuems

#33291

Looking for SPM Calibration Procedure for setting the Z-Axis ? | 18 March, 2005

Hello PMD Don't feel like that, we live with these MPM's. And we have over 10 years experience. Also never mess with the down stop on any MPM and you will be better off. Most of mpm's machines have a down stop of .0750 and it should never be changed, shouldn't even be on the set up screens. And take the size of the board ( x axis) and double that number, this number is the amount of down force that the blades should need to give a good print with. One misconception is the force is pushing the board down. If your printing with a "0" snap off ( which should always be the case) the down force is changeing the angle of the blade and nothing else. If you achieve a angle of 31-37 degrees the solder paste will roll across the stencil and if the paste is rolling it should give the desired results. Solder paste has to roll!!!! There is to much confussion on a very simple operation. Sorry but now I feel a little better harry

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