Yesterday morning, I was sitting here dreading the build-out of a NoCal prop or two. They aren’t difficult, but they take time. Also, I’ve been thinking “I need to make something new to print out (what – I don’t know).”
So, somehow, the two got combined. Part of building a NoCal prop is the prop spar. Not being a super-duper indoor fanatic, I use pre-made dowels that are actually medical Q-Tip shafts (yeah, I used to sell these). They are heavier than balsa – but they are stronger, too. I’m not a fanatic about conserving micro-grams, so they are good enough for me.
But there are two things that are critical to the creation of these spars: 1 – the prop shaft hole needs to be in the middle (r-to-l) of the spar and it needs to be perpendicular to the spar. So, rather than build a prop, I decided to see if I could tackle these issues with a little jig. It took just a little over an hour from empty page to printed and assembled product, ready to test.
Here’s the Volare Products NoCal Prop Spar Drill Jig (buy it HERE):
the Drill Jig in closed position
the Drill Jig in open position. It is made from two parts with a bit of printing filament as a hinge (the red in the photo). Features: both pieces are grooved to accept the dowel; both pieces have a 0.025″ hole drilled in the center, perpendicular to the spar groove; and it has notches designed to create spars with lengths of 4″, 3.5″, or 3″ in overall length.
you should set your prop shaft drill to a depth that goes through the base, the spar, and the lid.
For a 4″ prop, insert the dowel into the jig and make the end of the dowel flush with the end of the jig, as shown.
on the other end, trim the dowel flush with the opposite edge of the jig.
with the dowel in place and captive in the jig, drill from the “bottom” of the jig. It is pre-drilled at 0.025″ and the depth of the base will guide the drill squarely into and through the spar. Drilling from the top is NOT recommended, as the lid does not have enough depth to squarely guide the drill.
results
to trim to a a 3.5″ or 3″ length, open the lid and insert the drill or music wire into the new hole and into the base to locate the spar. Use a knife to mark the spar at one of the existing notches in the base. Remove the spar, cut the end, reinstall the spar, notch, and cut the longer end in the same manner.
the end product!
Great job George