On Thu, 15 Dec 2016 10:15:05 -0500, Bob Engelhardt
wrote:

On 12/14/2016 1:01 PM, wrote:
I thought about peristaltic pumps but the tubing doesn't seem to last.
And I think a pulsing pump might be better since I'm only needing a
drop or two at a time.
Eric


No suggestion as to tubing life, but as to pulsing: you could drive it
with a stepper motor & control the size of drop and frequency.
The beauty of most of the (at least cheaper) peristalic pumps is the
tubing is easily replaced and VERY cheap - and you CAN use differnt
tubing for different chemical makeup. A PWM controller can control the
speed of the little DCPM motors quite well, so if sized appropriately
you can control the coolant delivery very well - and they ARE
available with stepper drives or geared drives - but significantly
more money.