> >Fill the glass delivery tube with the substance you want to deliver. > >Connect the full diameter end to the smallest diameter flexible tubing you > >can find (this is particularly important if you plan to move the glass > >delivery tube to the target). Take a SPDT solenoid valve on the common > side > >put a short length of tubing with a closed end to act as a small pressure > >tank (the volume of this "tank" and the air pressure will determine how > much > >substance is delivered). Apply air pressure to one switched leg of the > >solenoid valve and connect the other switched leg to the flexible tubing > and > >delivery tube. > I have had a go with it, and it works quite nicely for that. Must try it > with some solder paste. As you say, the biggest hassle is choosing the > correct diameter nozzle/needle to use. Yeah, crank the pressure up and you can shoot BBs across the room using a steel tube for a barrel. Livens up a dull afternoon.... Win -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.