SMT adhesives

I am developing a DOE for evaluating SMT adhesives. I would like to evaluate 3 different vendor dispensing adhesives. I currently have the Heraeus PD955M and the Loctite 3609 and 3618 selected for evaluation. I would like to add another manufacturer. Does anyone have any suggestions on a comparable adhesive? Also, I would be interested in any information that would help me determine a techinque on measuring green strength as part of this evaluation. Component skewing and off-location defects, pre-cure, are a big concern so I need something that will hold the components in place during PCB population. A quantitative techinique would be desirable. Lastly, does anyone have any information regarding the reaction of OSP coating with the SMT adhesives? Are the adhesive's properties weakened by OSP?

Thanks!

Shane

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| I am developing a DOE for evaluating SMT adhesives. I would like to evaluate 3 different vendor dispensing adhesives. I currently have the Heraeus PD955M and the Loctite 3609 and 3618 selected for evaluation. I would like to add another manufacturer. Does anyone have any suggestions on a comparable adhesive? | Also, I would be interested in any information that would help me determine a techinque on measuring green strength as part of this evaluation. Component skewing and off-location defects, pre-cure, are a big concern so I need something that will hold the components in place during PCB population. A quantitative techinique would be desirable. | Lastly, does anyone have any information regarding the reaction of OSP coating with the SMT adhesives? Are the adhesive's properties weakened by OSP? | | Thanks! | | Shane | Shane,

I've recently been evaluating a sample adhesive (MA-420) that was given to me by Thermoset. It is a division of Lord Chemicals. As for measuring green strength, I couldn't find a good quantitative way of measuring it here. I ended up setting up a test pattern to place the same components on incrementally smaller dots, observing which adhesive allowed the components to skew first. I then repeated the process a few times to account for any kind of random disturbance.

John

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