I am getting closer to building the landing gear and after studying the plans It looks like wheel barrow tires with no bearings. "grease every ten hours was the big giveaway" are to be used. My plan was to use an azusa axle, http://www.aircraftspruce.com/catalog/lgpages/threadjackshaft.php?clickkey=127752 along with a thicker ID steel tube to allow the azusa axle to be bolted in place, suggestions are welcomed, azusa wheels are made of plastic so its much easier to make part 103 weight.
Fitting the Azusa axles seems a good idea, but there is one thing that would worry me. If you cut a thread on the inside of each end of a full width minimax axle so that you can attach an Azusa axle at each end then all the flight loads go through those threads. I would worry that as most of the time the plane is in the air the loading causes the axle to be in tension, there is the possibility that if the threads are not a good tight fit, or become rusty, then one or both of the Azusa axles could pull out from the main axle. However, this could be overcome by drilling through, and putting a securing bolt through the main axle and Azusa axle just inboard of the axle brackets on the undercarriage legs.
I must apologise. I forgot you're building a Himax, not a Minimax, so you won't have the flight loads going through the axle. Doh! Stupid me. However, a security bolt through the main and Azusa axle at each end might still be a good idea.
I don't think you are going to make Part 103 weight with a Himax. It might be possible, but I doubt it.
A Hirth F-33 is about the only engine option, unless you can find a good used Rotax 277. And you will also need an "A" gearbox for the 277, and they are not exactly common.
Why not go ahead and build the Himax as an E-AB? That way you don't have to "sweat" each ounce of weight, and you can seriously increase the performance. Used/rebuilt Rotax 503 Prov 8 engines are easy to find, with greater parts availability than a 277, 377, or 447. Pull a 503DCDI back to 5000 rpms at cruise, and you only burn about 3 gals/hr. With dual 6 gal wing tanks, that's 4 hrs.
Put Grove spring aluminum landing gear, or George S's custom fiberglass gear on your Himax, and you can land in some gnarly places, like farming turn-rows, cow pastures, etc.
Thanks for the constructive criticism termite. The goal isn't necessarily to make it part 103 weight, but to make it as light weight as possible. If I mounted a 503 The nose would need to be modified to handle the extra weight and the five gallon tank I have installed would have to be removed. Besides team offers brand new rotax 277s. The original goal was to make it as lightweight as possible and then clean the airframe up to get the least amount of parasitic drag possible.
I don't think you are going to make Part 103 weight with a Himax. It might be possible, but I doubt it.
A Hirth F-33 is about the only engine option, unless you can find a good used Rotax 277. And you will also need an "A" gearbox for the 277, and they are not exactly common.
Why not go ahead and build the Himax as an E-AB? That way you don't have to "sweat" each ounce of weight, and you can seriously increase the performance. Used/rebuilt Rotax 503 Prov 8 engines are easy to find, with greater parts availability than a 277, 377, or 447. Pull a 503DCDI back to 5000 rpms at cruise, and you only burn about 3 gals/hr. With dual 6 gal wing tanks, that's 4 hrs.
Put Grove spring aluminum landing gear, or George S's custom fiberglass gear on your Himax, and you can land in some gnarly places, like farming turn-rows, cow pastures, etc.
I might not trust that configuration of pin location and shaft size... presuming you cut the axle tube close in that bolt hole becomes a stress concentration right where stresses are highest.
The plastic wheels sound interesting but those solid bar axles are not your friend if you are looking to reduce weight.
I might not trust that configuration of pin location and shaft size... presuming you cut the axle tube close in that bolt hole becomes a stress concentration right where stresses are highest.
The plastic wheels sound interesting but those solid bar axles are not your friend if you are looking to reduce weight.
The bolt holes will still be the same as on the plans! I might even lose some weight since the main axle tube will be shorter to compensate for the little axle!
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