The Inside Loop
Weekend shop
Two tables were most active in the shop this past weekend: one had a helicopter going together and the other had an airplane—a project for each kid. For me, a tiny corner was free for a "someday" project.
Practice helicopter blades are relatively inexpensive, at approximately $12 a set. The last swap meet rendered us a bounty of blade samples, all for the helicopter-neophyte price of free. Better than the $12 deal?
One particular wooden set included a 325 mm blade and a 335 mm blade. My "someday" plan was to trim and match them. Even beginner-grade blades are precision-weighted and balanced to an exacting degree (they even match in length).
Trimming and matching
Of notable interest was the fact that shortening both a 325 mm blade and a 335 mm blade to 280 mm removes approximately "way too much" ballast material. The $12 deal might have been better.
The correct weight location was easy to find; it was right next to the metallic piece protruding from the band-saw-chomped end of the free accessory (soon to be resurrected as a helicopter blade). A channel was milled out of the lighter blade in the appropriate location, and hand-sculpted lead strips were inlaid so that each $6 portion of the free gift came into sync on the blade balancer.
Overnight, epoxy secured the ballast, and once cured it was prepared for careful blending back into the precisely molded factory airfoil shape—which is available for roughly $12 at the local hobby shop.
I spent hours with a fanatical eye and a selection of sanding tools, sculpting fashionable tips on the blade ends. Hours went by as I scrutinized the transverse curve to hone the critical lifting surfaces. A final check on the blade balancer showed that carefully painting one blade to match the other would yield a set of closely matched swap-meet masterpieces.
Finishing and painting
Layers of primer coated the bare wood and epoxy filler. A can of Wal‑Mart-brand primer, hiding in the cabinet for years, proved perfect for sealing surfaces exposed to silicone and carbide sanding. The can of paint must have cost me $1 ten years ago; and it isn't made anymore. Darn it, it's good stuff!
After 24 hours of "baking" over the electric heater that kept our provisional garage workshop toasty warm, the would-be $12 blades were wet-sanded in the guest bathroom, taking special care that gray paint water didn't get on the embroidered guest towels. When all evidence of the tooling was finally removed, a sealer coat of primer was added after 30 minutes of drying time over the heater.
Blades can be tricky to paint; there's no place to hold them while spraying and the entire surface must be coated. Using dowel scraps and paint stirring sticks from the hardware store (free if you ask nicely), handles were fashioned that could be screwed through the blade-grip hole. These would later be hidden by plastic covers—available with almost every $12 blade set on the market.
We settled on Rust‑Oleum Chrome for the finish, which would tastefully complement the tiny balls hidden under the black plastic links of the mechanics. The paint was left over from a Cub Scout award project—again, a major cost savings (high praise from the wife is certain). Careful paint application was completed under the best of conditions—out on the porch at 9:30 p.m. with blowing snow. It was found that when blades are painted at the same angle of attack as the driving precipitation, there's little chance of the fresh, frostbitten paint being contaminated. In between paint coats, I found a sale on wood helicopter blades at one of my favorite websites.
The blades gleamed as solvents baked out of the rustproof paint—an important consideration when painting wood. After 48 hours, the masterpieces of sweat, grit, and Maxwell House were ready for the final check on the balancer. The verdict warranted just a tiny strip of tracking tape, which also covered a snowflake-sized blemish.
Assembly and result
The blades are now mounted to my son's well-earned 400-class electric helicopter (another swap-meet special). He's proud that his machine looks good, and his building supervisor (daddy) is glad to have played a part.
Conclusion
What does this story mean? Builders build because they want to. Whether it's an airplane, helicopter, or X‑Prize contender, RTF or scratch-build, stabilizer or wheel pant—have fun and enjoy the opportunities that this great hobby brings.
MA
Transcribed from original scans by AI. Minor OCR errors may remain.
