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Adhesive Dispersion Specifications

CJN

#22055

Adhesive Dispersion Specifications | 21 October, 2002

We hare having an issue with our chip shooters misplacing or not placing parts all together. We have traced it back to our adhesive machine. We are using both single and double dot nozzles. I feel that the biggest problem is excessive amounts of glue on the dual dot nozzle. The glue dots are bleeding around the part and clogs the nozzle tip on the chip shooter.

What are the recommendations on using single dots for all discrete components?

What is the recommended allotment of glue dispersion per part size?

What are some of the best ways to measure dot sizes to ensure proper placement amount on all shifts?

Thanks for your help, ChrisN

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Sean D

#22141

Adhesive Dispersion Specifications | 24 October, 2002

Hello TEC,

This may be a good question for the Apps Engineers at your dispenser manufacturer.

By providing the identity of the epoxy and the components you are placing, they should be able to make some recommendations for getting the proper dispense profile established.

With their experience, they should be able to aid with some guidelines for dot size vs. pad size taking into consideration the material being dispensed.

I would recommend giving the factory a call and taxing their brains a little.

Good luck, Sean D

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#22143

Adhesive Dispersion Specifications | 24 October, 2002

The logical course seems like you would just back off on the shot size or go with a smaller diameter nozzle, but if this is something new and you've been running fine up until recently then something has changed.

Check the condition of your nozzles. If they're bent, dinged, partially clogged, or otherwise in poor condition there's not guessing where that adhesive is going to go.

Another question...if it's so bad it's climbing up the sides of your parts and mucking up your placement nozzles, how much are you getting on your pads?

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