Rescuers of going-crazy-dispenser-technicians, Morning to you all,
I must have a talk with you between 1,600 eyes.  Take a chalk go to an airport and paint two paralell lines, 1000 meters long and 150 meters apart. Then make obstacles here and there that makes the path only 100 meter wide or even 75 meters. This is your runway for taking down a Galaxy. Could go, but what if you have some Cessnas att the same time? That's what the silver flakes have too pass in a 10mm long syringe, with a nominal diameter on 150um, a minus tolerance upon that plus other obstacles on the walls. Now,

a ) suggest that you get some flow hindrance near the syringe's outlet, caused by large flakes agglomeration, what will happen the nearest tenths of seconds after the auger stopped dispensing? Won't there be a small overpressure on inside of the syringe? And won't that small overpressure decrease simultaneously with the small amount of paste that passes the obstacles and comes out of the syringe? Can this be a reasonable theory why we see small amounts of paste dripping out from the syringe when the robotic make a secon or two pause?

b) won't it be a problem for all flakes to pass all these 10 mms long syringe in a 80-150um channel, especially if many flakes differ from the paste's medium size, I mean 30-50um  instead om 5um? And won't it be even worse if  som flakes agglomerated already in the pump before coming to the syringe?

c) coming finally to my proposal. If you cut your syringe to, let's say 2mm length instead of 10mm, won't the whole problem be much smaller? IF there is still some obstacles, the volume on inside the syringe is much smaller = less leakage of paste between dots (pauses), because built-up pressure will go down much quicker.  And the clogging risk ought to be much smaller even that, won't it because 4/5ths of the tunnel is gone.

Aussilek use to be brightest, but there ought to be more with  (he-he).  Severe question: am I right? Please, say da. If the theory seems OK, we will make a very rapid effort in order to get the precision line running /

Ingemar Hernefjord
Ericsson Microwave Systems

PS. Following question: with a 2mm long syringe, could laser be way to remove remaining obstacles so that a 150um-minus75um- syringe becomes a  true 150um syringe? Or jetwater? Or sandblast?

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