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Frameless Stencils

Michael Uganecz

#7863

Frameless Stencils | 13 January, 2000

Hello,

I'm doing some research on frameless stencils/stencil frames and I'm looking for people's thoughts on them. I'm looking for any and all thoughts/opinions on how well they work or don't work. Some specific areas of interest: tensioning in one direction vs. both directions, ease of use, handling of foils and danger of sharp edges. How well do the frames work and are there any problems with any of the frames on the market. Are they worth the cost?

Thanks in advance for any and all feedback.

Mike Uganecz

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mike d

#7864

Re: Frameless Stencils | 13 January, 2000

Michael,

Good afternoon. My experience with the frameless stencils has been less than optimal. I tried the universal stencil system about a year ago and these are my experiences.

1) The stencil manufacturer supplied me with a free frame to try out with their foils. The original foil that I received was a 6 mil stainless steel that the foil house neglected to put the fiducials on.

2) While installing the foil onto the frame, my operator snapped the head off of one of the tensioning screws. The result was uneven tensioning on the foil. The tensioning screws were of an inferior grade and could not handle the ordinary force applied by an operator.

3) While attempting to remove the foil from the frame due to the broken screw I managed to slice almost halfway thru my finger on the edge of the foil. This was in spite of the fact that I was conciously being careful due to the sharpness of the foil.

4) When I informed the foil house of these problems, they supplied me with a new frame. When I went to install a foil to the frame I found that the frame was not square and I could not install the foil. It was at this point that I packed up the frame and sent it back, and I have not touched another frameless stencil since.

In my opinion, it is more than worth the money to have a stencil house manufacture individual stencils due to the sharpness of the bare foils. I would rather pay the extra money and know that I have minimized the risk to my operators than save a few dollars and risk operator injury.

Just my thoughts,

Mike

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#7865

Re: Frameless Stencils | 14 January, 2000

We are using frameless stencils with a frame system tensioning in X- and Y-direction. After first quarrels with our stencilhouse about the correct position of the tensioning holes ( they needed 4 tries to get it right) there are no problems any more. After 3 years not one injury due to sharp edges and no damaged stencil. The costs were about 2,5K $ and with an average of 2 stencils a month we think we can live with it. The system is rectangular and solid in all aspects and we did not make such discouraging experiences like mike.

regards

Wolfgang

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John Thorup

#7866

Re: Frameless Stencils | 14 January, 2000

I'll have to go along with Wolfgang as having a good experiance with frameless. We have been using a system from IIT in California for about a year. I was sceptical at first because of this system's X only tensioning but it does work. We use mostly 6 mil plates and regularly print down to 20 mil pitch. The frame was about $800 and the plates are about $150 for laser cut. No injuries here either. This topic has come up a number of times so an archive search will yield more info. John Thorup

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Michael Uganecz

#7867

Re: Frameless Stencils | 18 January, 2000

Thanks for the feedback. It's been helpful.

Michael Uganecz

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