Gear handle design

Responded privately.

Initial batch of 8 handles sold. Taking names for future batch, no deposit, no commitment. (No time either! - but being guilt driven, will find time when enough people ask.)

bumper

I've started making another (maybe the last, due to time constraints and other commitments) small batch of gear handles. Not cheap, but I believe you will be pleased with the quality and more importantly, how they perform.

$200 shipped to US - overseas at cost. Satisfaction guaranteed or your money refunded, with some grumbling. :c)

https://www.youtube.com/watch?v=2NEjytbOWbI

Note this gear handle will fit other Schleicher models, and can be custom made for some other makes too, contact me for details.

contact: bumperm "the usual little symbol" frontier "period" com

We just finished installing the Bumper Gear Handle in my ASW 22 BLeE. Although I haven't exercised it in flight, I can attest to the fit and finish---outstanding! My ship is now completely Bumperized: gear handle, yaw string, and quiet vent. All the designs are innovative, and the quality is second to none.

Dan Somers/ID
Port Matilda, Pennsylvania

My ship is now completely Bumperized:

I wish Bumper would design an entire ship...

Boggs

If you have trouble raising the gear the first thing to check is that the horizontal rod the handle slides on is lubed. This needs to be done at least annually.If it has old/no lube Herculian strength is required.

As Bumper suggested, a push over makes the gear "lighter" due to reduced g but the helper spring still has normal force. A wild maneuver is not required. I regularly raise the Duo gear this way on tow.

But judging from the craftmanship and functionality of the Quiet Vents and MK 5 supersonic yaw strings on my ships you won't be disappointed with this brilliant invention.

KS

I'm flattered. Thank you for the kind words.

As Karl says, to minimize friction, it's important the sliding and hinged points are properly lubricated. That would be the first step in minimizing the effort needed to operate manually retractable gear. If that doesn't improve things, time to check further, an over tight hinge or pivot bolt on some designs can add friction.

One way to check gear is with the fuselage on the trailer ramp so you can swing the gear clear of the ground. Unlock and drop the gear so it is hanging down unlocked. Now you can move the gear by pushing by hand directly on the wheel, moving it fore and aft. This provides more of "feel" than moving it with the gear handle, looking for any unusual resistance to free movement. Depending upon where the wheel is in it's arc of travel, normal resistance to movement will vary based on gravity, assist and over lock springs, and friction.

Besides proper maintenance, the effort required to cycle the gear will be affected by a number of factors including mechanical design and how that design relates to human factors and ergonomics. The bumper gear handle (BGH) is designed to improve upon the last part of that equation.

BGH history: When I got my ASH26E in 2003, I realized right away the gear handle position and orientation was sub-optimal for me. I made a number of different handles including the prototype for the BGH. And sent several of those handles to an experienced pilot for his evaluation. After testing, he allowed that he preferred the original factory handle. For me, the BGH design dramatically improved the ease of gear operation, completely eliminating all untoward effort. However, based on that evaluation, I concluded optimal gear handle design must be strongly variable based on pilot preference, and frankly, not worth pursuing as I didn't want unhappy customers and the hassle of lots of returns and refunds. I shelved the idea of offering the BGH indefinitely.

Forward 12 years, another pilot, upon seeing an old picture of my BGH, asked if I'd build one for him, I expressed my concern about one size not fitting all thing. He remained adamant, wanted to give it a try. I acquiesced and made one and it worked every bit as well as he'd hoped for, and as it did for me. Hmmm, maybe on to something after all? After all positive feedback from the first 9 customers, I guess so. Still, if you acquire one and are not pleased - or for any reason at all, you may return it undamaged for a refund, including cost of return shipping (USA only - overseas returns must be post paid).

The "standard" BGH has a milled slot to accept the ship's flattened steel tube gear handle shaft. Dimensions of the slot are 0.880" long by 0.281" wide. The handle itself is approx 6" long, 1-3/8" diameter, foam covered w/vinyl end caps. Slot is 1" from end. Location and dimensions of slot can be custom ordered to fit - contact for details.

Availability: 3 in stock, (made in batches, wait time up to 6 months, includes custom orders). Payment accepted only when ready to ship.

bumperm (ubiquitous "at" thing) frontier (dot) com

Two gear handles available. Returned unopened when buyer decided to sell his 2-place ship. Contact info in first post of this thread.

1 minute video at https://www.youtube.com/watch?v=2NEjytbOWbI

thanks,

bumper
zz
Minden