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MPM Print Parameters



MPM Print Parameters | 15 August, 2001

Hello All, We have an MPM 2000 screen printer. My question is this: we are having a stencil made that has both top and bottom side on a single foil. Our Process people are unsure if the machine parameters will allow it. The board size is 19x15. Can it work? What are the concerns?

THANKS! BTW, MPM's tech support has thus far been unresponsive.

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Michael Parker


MPM Print Parameters | 15 August, 2001

I would consider the fab placement in the printer to be of more concern than the pro's and con's of a single foil for top and bottom print.

Do to the larger size of the fab you will have to align the top and bottom layers sequentially on the foil. One in front and one in back. This means you need to consider fab alignment. Are you using the automatic tooling pin alignment in your printer? Will the fab always be placed forward in the printer or are you intending to print the second side with the fab placed far to the back? This would necessitate moving the fab supports and vacuum boxes. It would be better to leave the fab forward, regardless of which side is up and rotating the stencil 180 degrees between runs. This also forces the centerline of each stencil to remain true and in alignment with each other. Can you rotate the stencil frame and achieve center alignment?

One final thought - why do 2 on 1 anyway? Are you trying to save the cost of one stencil? What if you find that one of the two aperture sets needs to be modified? That means you will need to get both sets cut again rather than one. Is your stencil house charging a flat rate, regardless of quantity of apertures? Or is the charge proportioned by aperture count? Are these laser cut or chemical etch stencils? If chemical etch, I would be wary of good center line alignment between the two sides.

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MPM Print Parameters | 16 August, 2001

Why would you have a stencil made without knowing the capabilities of your equipment?!!? Ok, the manager in me has spoken, you can cut a few hundred bucks off a stencil by putting two on one, but the reply Michael has posted brings up many other issues you need to consider. My only point is to suggest possibly etching the same board twice on one stencil and again for your other board. If one gets damaged or worn, you have the other side. That way you essencially save the same amount of money on stencils, and avoid a lot of hassle down the road.

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MPM Print Parameters | 16 August, 2001

Awww, blank those fine tech support people at MPM. We know more than they do.

Having said that, duh, umm er, please clarify the problem. * Are you concerned about paste squirting through the holes of the side 2 portion of the stencil when you are printing side 1? * Is it that the frame might not be BIG enough for a stencil containing both sides? * Are you wondering if the board should be paneled-up to match the stencil? * What????

Here�s what we have locked-in: * MPM 2000 screen printer. * Foil [metal??] stencil. * Openings for two different designs in the foil. * Board size is 19x15

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Mike O


MPM Print Parameters | 17 August, 2001

I do not use MPM printers but I find it hard to believe there would be a problem, assuming the MPM printer can be configured for Edge reference stencils. The double image stencil is basically two edge reference stencils in one. Assuming the art work is small enough so there is room between the images for the paste roll why should there an issue? The printer will reference the fids for alighment so tooling should not be an issue. The operator would simply rotate the stencil to print the side required.

The pros are half the cost (depending on the aperutre count) and half the storage space required. Also, only one stencil is issued to the floor that will complete the entire run.

The negs are as stated above, damage the stencil and you just lost the ability to print either side.

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