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SMT electronics assembly manufacturing forum.


Frameless stencils

pw

#11299

Frameless stencils | 28 May, 1999

We are looking into frameless stencil systems for screen printing. Outside frame size of 29x29.

Pros: smaller storage requirements and cheaper stencils.

Cons: sharp metal edges, additional change over time required

Can anyone relay their experiences with these types of systems?

Thanks Peter

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Earl Moon

#11300

Re: Frameless stencils | 29 May, 1999

| We are looking into frameless stencil systems for screen printing. Outside frame size of 29x29. | | Pros: smaller storage requirements and cheaper stencils. | | Cons: sharp metal edges, additional change over time required | | Can anyone relay their experiences with these types of systems? | | Thanks | Peter | We, as some others on this forum and other sites, currently are using the Alpha Tetra system. We use the 29" square DEK frameless fixtures with the "improved" internal surface area. The positives are as you stated. Some "minor negatives are:

1) Though lisenced to some other stencil foil makers, some of them make their "real" money supplying the whole frame/foil package (our cost on total package exceeds $550 compared to foil only costs of less than $250), so can you blame them for being less interested than Alpha for wanting the foil business without the frames?

2) Operators think the new foil/fixture combination too heavy but they most all are enrolled in heavy weight training classes under my direction therefore getting stronger everyday.

3) Operators think the foil edges too sharp thougn no blood letting yet.

4) Have not blown the rubber bladders yet but promised free replacement fixtures WHEN this occurs.

5) Operators cannot see the "micro" apertures etched on the foils - got them looking on this one (about twenty swore they could see the non-existent little muthas but had to look real close).

6) Cleaning process a little clunky in our SmartSonic but gets better with practice.

7) Wouldn't go back to frames for anything.

Earl Moon

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KEVIN SIMPSON

#11301

Re: Frameless stencils | 31 May, 1999

| We are looking into frameless stencil systems for screen printing. Outside frame size of 29x29. | | Pros: smaller storage requirements and cheaper stencils. | | Cons: sharp metal edges, additional change over time required | | Can anyone relay their experiences with these types of systems? | | Thanks | Peter | Another problem that we had was stencils being damaged due to being handled more.etc. having to mount to frame...We concluded that unless you just don't have the storage space to handle your current # of framed stencils, there is really no need or benefit to framless.

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Jeff Strumpf

#11302

Re: Frameless stencils | 1 June, 1999

| We are looking into frameless stencil systems for screen printing. Outside frame size of 29x29. | | Pros: smaller storage requirements and cheaper stencils. | | Cons: sharp metal edges, additional change over time required | | Can anyone relay their experiences with these types of systems? | | Thanks | Peter | Hi Peter, Earl is correct in his evaluation of tha Alpha Tetra system. I wanted to add that this system not only saves space and cost over framed stencils but is much faster to use (<30 seconds cycle time) than traditional cam and lever types. The most important feature is the improvement in print accuracy as the foil is mechanically connected to the frame (no glue or mesh stretch) and is under higher tensioning (43 N/cm vs. 25-30 N/cm). The result is 5X less deflection during a print stroke (critical as you print finer and finer pitch apertures). I believe the Alpha Metals web site has info on this product.

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Earl Moon

#11303

Re: Frameless stencils | 2 June, 1999

| | We are looking into frameless stencil systems for screen printing. Outside frame size of 29x29. | | | | Pros: smaller storage requirements and cheaper stencils. | | | | Cons: sharp metal edges, additional change over time required | | | | Can anyone relay their experiences with these types of systems? | | | | Thanks | | Peter | | Hi Peter, Earl is correct in his evaluation of tha Alpha Tetra system. I wanted to add that this system not only saves space and cost over framed stencils but is much faster to use (<30 seconds cycle time) than traditional cam and lever types. The most important feature is the improvement in print accuracy as the foil is mechanically connected to the frame (no glue or mesh stretch) and is under higher tensioning (43 N/cm vs. 25-30 N/cm). The result is 5X less deflection during a print stroke (critical as you print finer and finer pitch apertures). I believe the Alpha Metals web site has info on this product. | | Mike and Peter,

I forgot the most important part. Hell Mike, I knew you'd come through with the real stuff - the tension never lessens. It can't. Also, the thing works better everyday as our operators lift weights and wear glasses to see the "micro-apertures." Seriously, these things (Tetras) are great. Did I already mention this?

Thanks Mike and Peter,

Earl Moon

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tannlin

#11304

Re: Frameless stencils | 4 June, 1999

| | We are looking into frameless stencil systems for screen printing. Outside frame size of 29x29. | | | | Pros: smaller storage requirements and cheaper stencils. | | | | Cons: sharp metal edges, additional change over time required | | | | Can anyone relay their experiences with these types of systems? | | | | Thanks | | Peter | | | Another problem that we had was stencils being | damaged due to being handled more.etc. having to | mount to frame...We concluded that unless | you just don't have the storage space to handle | your current # of framed stencils, there is really | no need or benefit to framless. |

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