When a fluid drips out of the dispensing tip at the end of the dispense cycle, it usually means one of three things: air in your fluid, the vacuum feature isn’t set properly, or a faulty solenoid valve. Generally speaking, as long as you’re using dry, filtered air to supply the dispenser, the solenoid valve should work fine. In fact, there are very few instances of faulty solenoid valves.

That leaves us with air in the fluid and the vacuum feature. When dispensing a watery fluid, the vacuum feature prevents dripping between dispense cycles. When setting the vacuum feature for a particular fluid, you want to increase the vacuum slowly until the fluid completely stops dripping from the dispensing tip. If you notice that bubbles are being sucked back into the syringe reservoir, you have too much vacuum. In that case, simply back off the vacuum a bit and you should be fine.

We typically find that the main cause of dripping is from air in the material or from an air bubble trapped in the hub of the dispensing tip. If you are dispensing a watery fluid and using a small-gauge dispensing tip, sometimes it is difficult for an air bubble to purge itself out of the dispensing tip. In this case, we recommend filling the hub of the tip with your fluid first, then attaching it to the bottom of the syringe reservoir. For thicker pastes that have air pockets, the best way to eliminate dripping is by centrifuging the material inside the syringe to remove most of the air pockets. This procedure will ensure trouble-free, drip-free dispensing.