Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


Stencil foils delaminating

Views: 1923

#44972

Stencil foils delaminating | 9 November, 2006

We are having continual problems with our stencil bindings falling apart in our washer.

We use a PMR5000 ultrasonic with Vigon sc2000 cleaning fluid. We cycle them in the washer for about 9 minutes.

The fluid sometimes heats up to 105 deg F.

Our stencil house has switched us to a more robust binding glue. Even with this new glue we are starting to see delamination after multiple wash cycles.

Does anyone else have this problem ?

reply »

#44978

Stencil foils delaminating | 9 November, 2006

This link will explain the cause of the delamination: http://www.smartsonic.com/ssonicfaq.html#4

You need to shorten the cleaning cycle and lower the temperature. Provide me with your mailing address and I will send you a sample of our 440-R SMT Detergent. The 440-R SMT Detergent will reduce the cleaning cycle time to about 2 minutes and the heat can be reduced to ambient temperature.

Regards, Bill Schreiber Smart Sonic Corporation E-mail: Bill@SmartSonic.com

Web: http://www.SmartSonic.com

reply »

KEN

#45001

Stencil foils delaminating | 11 November, 2006

Hey Sr. Tech. Before you get crazy with changing the process or chemistry I would first verify you are using the correct mix ratio. A refractometer can be a useful tool in these cases.

I have seen this in the past where the maintenance technician failed to read the mixing instructions and was mixing concentrte directly into the bath. The stencils would delaminate in 5 minutes. Needed 6:1 water to chemistry. Oops!

reply »

#45009

Stencil foils delaminating | 13 November, 2006

This fluid is pre-mix from Zestron.

reply »

KEN

#45029

Stencil foils delaminating | 14 November, 2006

I would still verify what you are receiving and your current bath setup. This only because you are experiencing problems. Simple check, takes 2 minutes.

I have seen this before, but it took 8 hours to delam at with pre-mix. This was 5 or 6 years ago...

reply »

#45343

Stencil foils delaminating | 22 November, 2006

We had the same issue. Switch to the 440-R and remove your heat. Your wash cycle can be changed down to 2 minutes. Make sure to mix the correct amount, and you want have anymore delam's.

Kevin S

reply »

Perb Habes

#45344

Stencil foils delaminating | 22 November, 2006

Me tinks the Smart Sonic is a good machine.

reply »

#45533

Stencil foils delaminating | 24 November, 2006

"The fluid sometimes heats up to 105 deg F."

Not sure what you mean here...is it set at 105 but rarely gets there, or is your temperature dependant upon another process to heat it up? Also, what temp is your rinse water?

We used to use a U/S cleaner that rinsed with DI and while the wash tank temp was fine, when our inline cleaner was running it recycled to the D/I system and the rinse water got too hot. We had stencils falling apart all over the damn place.

reply »

#45642

Stencil foils delaminating | 27 November, 2006

The fluid heats up to 105-110 from the ultrasonics running, and or from the fluid filtering pumps.

The rinse temp is always the same as the wash. It is a single tank with a partition welded in between. (One side rinse, and the other side wash)

FYI Steve, I have been told that DI water can be worse than some chemicals when it comes to this delaminating problem.

We have reduced our cycle time and I am keeping an eye on things.

Also, the chemical that was mentioned in the above post does not clean glue very well from what I am told. I need the ability to do both in one washer.

Thanks

reply »

PCB Soldering Tools

reflow oven profiler