EAA Sport Aviation - February 2010

HANDS ON

BUILD-IT-YOURSELF

An instrument you can build for under $5
CHARLIE BECKER
Inclinometer

I JUST STARTED TO GET SERIOUS about my Sonex’s instrument panel. My goal is to keep it simple (aka cheap). Since I haven’t been in the market for instruments in a while, I was absolutely taken aback by how expensive slip-skid indicators are. I found prices anywhere from $40 to $90! There had to be a better— cheaper—way, so off I went to the EAA Sport Aviation online archives. Bingo! Val Bernhardt, EAA 59376, had shared plans for a homebuilt inclinometer back in January 1982. Here is a full-size template to make an inclinometer for well under $5. Plus you’ll have the satisfaction of building it yourself.

The hardest part of building this instrument was finding the raw materials. I found my supplies at a True Value hardware store after striking out at the local big-box store. Try your local bike shop for the ball bearing. You can scale the template down a bit if you don’t want to burn that much space on your panel. I copied the template on a photocopier at 80 percent. I modified mine by using a tubular rivet (3/16 inch by 1/4 inch) as a plug and used a smaller vinyl tube with a 1/4-inch outside diameter and 0.170-inch inside diameter. I liked the tubular rivet because it hides some of the trapped air within the mineral spirits we used as the liquid medium.