One tool I haven’t owned is a vacuum pump. That’s because good vacuum pumps are expensive, and cheap vacuum pumps are – well – they’re not good vacuum pumps. So I finally decided to go with the 3rd option. I made my own. I started with these instructions from Veneer Supplies, and then used a few bits I had around the workshop. The result looks like this:
The advantage of this approach is that while it might have as many quirks as a cheap pump, I’ll be able to fiddle with it when it misbehaves.
Here’s a closeup of the business end.
Hiding in there are a switch that measures the vacuum, a solenoid that controls the airflow, and a venturi that uses compressed air to generate a vacuum. That all connects up to the storage tank like this:
When the vacuum drops below the selected level, the solenoid opens and charges the venturi, which sucks more air out of the tank. It can easily maintain a vacuum of 23 or 24 inches without working too hard. It can even do 25 inches, but it’s struggling a bit at that point and the air compressor is running more than I would like. It can also hold a vacuum for an extended period of time, which is useful.
In addition to building the pump, I also installed this cool retractable hose reel yesterday.