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Problems with frameless stencils on MPM??

james

#35471

Problems with frameless stencils on MPM?? | 13 July, 2005

Does anyone else have problems with the frameless stencils on the MPM UP2500. I noticed after I do a stencil height adjustment it looks like the vacuum actually pulls the stencil to the board.

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dougs

#35473

Problems with frameless stencils on MPM?? | 13 July, 2005

if your vacuum is getting through your board then it sounds like your vacuum tooling is wrong. you shouldn't have vacuum points at areas of the board where there are PTH's or via's.

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james

#35476

Problems with frameless stencils on MPM?? | 13 July, 2005

I dont have much choice because the vaccuum is right underneath the whole board, it sucks the board fairly hard. The only thing holding the board is the vacuum and board supports.

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URL

#35481

Problems with frameless stencils on MPM?? | 13 July, 2005

Maybe you stencil height measurement is being affected. Check your tactile sensor, it may be sticking due to paste or adhesive getting on it.

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pr

#35488

Problems with frameless stencils on MPM?? | 13 July, 2005

Sounds like your stencil might not be tight enough. Are you having print problems because of this? If not I wouldn't be too worried about it.

good luck, pr

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james

#35506

Problems with frameless stencils on MPM?? | 14 July, 2005

The tactile sensor seems to be fine. I think it may have something to do with the stencil being not as tight as to one that is on a stainless steel frame. When we set the height of the stencil we have to do it towards the back of the stencil because of the aperatures.

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GEB

#35520

Problems with frameless stencils on MPM?? | 14 July, 2005

The vacuum will pull the stencil towards it if there isn't a frame because the front and back of the stencil aren't being supported by anything. Can't you use a frame, they're only about �20.

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james

#35521

Problems with frameless stencils on MPM?? | 14 July, 2005

We use the Frame with the frameless stencils, but they seem to not be as tight as the stainless steel frame stencils

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pr

#35525

Problems with frameless stencils on MPM?? | 14 July, 2005

The big advantage of frameless is storage space. The big disadvantage is getting the stencil tight (and cuts on operators).

pr

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#35533

Problems with frameless stencils on MPM?? | 14 July, 2005

This is why I disqualified frameless stencils. All that I have seen do not seem to be tight enough. Introducing 1 more variable into screen printing did not seem like a good idea.

Jerry

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#35593

Problems with frameless stencils on MPM?? | 18 July, 2005

Price is a pretty big deal also. We used IIt pro frames for about 6 years but moved to QTS Wizard frames, they work pretty well, We have no issues with them not being "Tight" They work from all 4 axes and have "push down" bars as well to work in the Z axes.

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