Eagler's Nest
Airframes => Single Seaters => XL => Topic started by: Sawyer on February 09, 2020, 06:54:22 PM
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Might be a bit premature but has anyone used these wheels off bmx bicycles? Saw some photos similar. 18 inch
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MIN SIZE IS 20" FORTY SPOKE
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MIN SIZE IS 20" FORTY SPOKE
Weight is paramount.
However, as far as strength goes the more spokes the better. The wider the hub the better. Cross 4 lacing is better than cross 3.
Google lacing patterns...
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highest strength lowest weight.
Dan,
Please link best post on this. I have search and found much from Google, 'sheldonbrown.com'
we can read until our eyes bleed, I'm here because Leonard has sold me on LE. but also eaglesnest forum.
I have have the scrougeable gene, dumpster driver, exploiting american wastefulness(just throw it away and buy a new one), mostly church of craigslist.
BMX is bicycle purposely build for 150 lb rider, Mongoose is popular brand(although is cheap Chinese). I found 20" 36 spoke that weights 4.3 lbs.
currently looking at converting axle/hub.
MY RULE OF THUMB is follow whats been successful and well document here!
Thank you,
Theo
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Dan,
Please link best post on this.
Thank you,
These may not be the best, but they are some.
https://www.eaglersnest.com/forum/index.php?topic=1053.msg5622#msg5622 (https://www.eaglersnest.com/forum/index.php?topic=1053.msg5622#msg5622)
http://www.westcoastpiet.com/wire_wheels.htm (http://www.westcoastpiet.com/wire_wheels.htm)
And there might be a couple of more where I got the last one here:
https://www.google.com/search?client=firefox-b-1-d&q=pietenpol+spoke+wheels (https://www.google.com/search?client=firefox-b-1-d&q=pietenpol+spoke+wheels)
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No not from scratch, render and retro fit yes but...
I may have an engine thats 110 lbs. so lightest is best
I remeber Steve Kiblinger had a good... wait anglefire yes thats it. older but good yep
http://angoraaffaire.com/leu/id48.htm
Also notice Joe spencer swapped in the one piece T-6 Aluminum, found website for same but 2K?
https://www.groveaircraft.com/landing_gear.html
Watching Les Holman he has lightest no spring with much experience landing although...
Thank you Dan!
Airshows are canceled this year, this makes me sad.
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No not from scratch, render and retro fit yes but...
You might try here...
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1311.R8.TR11.TRC1.A0.H1.X20+inch+bmx.TRS0&_nkw=20+inch+bmx+wheels&_sacat=0 (https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1311.R8.TR11.TRC1.A0.H1.X20+inch+bmx.TRS0&_nkw=20+inch+bmx+wheels&_sacat=0)
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I've been digging into the wheel thing for a bit so I'll share what I've come up with though it certainly shouldn't be taken as the last word.
A poorly built steel wheel is likely weaker than a well-built aluminum wheel (and either is likely stronger than molded plastic!), and the steel will be MUCH heavier. Also, cheap wheels won't have the possibility of upgrading the brakes should you decide to add them later. Of course, lightness costs and so there starts to be a point where the gains in lightness are not justified by huge increase in cost.
You want to have a recumbent-type hub on your wheel – they are designed to be cantilevered from one side – a standard wheel hub is not and the loading is much much different. The axles on regular bike wheel hubs are small and won't handle repeated loading (reliably). Recumbent wheels are also designed to handle lateral loads well. This type of loading never shows up on a standard bike wheel and the plastic 20" bike wheels would be particularly poor in handling that type of lateral loading. https://www.utahtrikes.com/UTCAT-230.html lists (3) reasonably (as far as high-quality bike gear goes) priced recumbent wheels for sale. All of them have mounting flanges for disk brakes (but they don’t come with brake rotors, tubes or tires – we’ll get to that). They sell for between $100 and 150 bucks a wheel. They don’t list the weight (I will report back after I hear from them), but I would expect 1.5-2lb/ea. range? You could have custom wheels built with a carbon rim at $800/ea. and you would save 1/2lb per wheel (what’s it worth!?)! They do make wide rims for really fat tires, but this would add a lot of weight (IMO) and the smaller wheels should handle the abuse without having to go to ‘balloon’ tires, but it could be a unique look...
Tires are another area that is important to the overall landing gear package. 20" (406) wheels are the right size for an ultralight (IMO) because when you go smaller than the that load-rating on the tires drops considerably -- even for high-quality recumbent tires. If you go taller than 20”, the lateral forces start to be considerably larger and more difficult to deal with (plus the geometry on the landing gear could potentially start to be an issue, but that’s for another post). 20” seems to be in kind of a sweet spot of not too heavy, but strong enough. I compiled a spreadsheet but there is still a lot of work to do on it – I will upload it. I mostly did it to paint myself a picture of what was available and to see if I could spot any trends.
What I found out was that only one company really had the cojones to list tire ratings and that was Schwalbe. Since they are from Germany, and Germany has a ton of regulations, the tires are made to a very high standard. There are two reasons I think there is a lot of good 20 in. tires out there on is that BMX riders pound the snot out of their bikes and that requires a robust tire. The other is the introduction of e-bikes, which go faster and have a larger overall payload (good for us). The standout tire IMO would be a Schwalbe Super Moto X. It is load rated for 115kg (254) each at 50 kph (31 mph). That should be right in the range that the LE needs (there will be margin on that for g-loading etc). There are several other Schwalbe XX-406 tires that would likely work and if weight is an issue, then there are some tires that are very close in load rating but are considerable lighter (some very near a pound a tire!). at somewhere between 4-5lb for a set of wheels and tires bike tires are going to be hard to beat for weight!
Finally, the other nice thing is that the bike brakes would be more than adequate in this application and they are very lightweight and could be added later if you buy the good wheels up front. I don’t think anything aircraft-related can compete with the lightweight offered by bicycles, and so if you need to save weight, I think bicycle good bicycle wheels and tires are seemingly a good way to go.
I have an Excel spread sheet with tires data in it but I can't upload it...
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This video shows an emergency landing and high speed swerve that resulted in the landing gear having to be replaced. The Tuff wheels remained in service...
https://www.youtube.com/watch?v=VIIRW8u8nB8
This one is self explanatory
https://www.youtube.com/watch?v=sZ7dtrRrSTg
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Good post. It shows how strong those bicycle wheels really are. That looks like a 4" Maxxis tire, which I didn't list because of the weight, but I'm sure it would work fine if weight wasn't an issue (although I've read where the 4 inch wide tires prefer a wider rim, which also weighs more). I think the 2-2.5 inch tires are rated for more than enough weight for what we are using them for, and that rating is for continuous load -- not a momentary load that would likely result from a 'firm' landing -- that should be much higher. A lightweight recumbent wheel should have enough axle without removing the bearings and running without them, although for as much as they get run on an airplane a little grease might be enough. Personally I would prefer bearings.
I stand corrected on the Skyway Tuff wheels -- those are more robust than some of the cheaper plastic wheels I've seen in the past, but it lists that weight as 10lb -- I assume that is a shipping weight? or is that 10 lb/pair? Do you know what the wheel weighs? I think they look the part, but my guess is that they are heavier than a quality spoked wheel.
How do I upload a spreadsheet to the site?
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Basically you hit the plus sign at the bottom of the text editor input box and hit browse. Surf your folders and files and attach it.
You might watch this: https://www.eaglersnest.com/forum/index.php?topic=1864.msg10573#msg10573 (https://www.eaglersnest.com/forum/index.php?topic=1864.msg10573#msg10573)
Tuff wheel, tire, heavy duty tube and cheap bearing below to fit 3/4" axle tube weight 4 lbs 4 oz. 8.5 lbs for the pair.
https://www.leadingedgeairfoils.com/20-tuff-wheel-hub-special.html (https://www.leadingedgeairfoils.com/20-tuff-wheel-hub-special.html) https://www.leadingedgeairfoils.com/3-4-i-d-x-1-3-8-o-d-standard-ball-bearing-wheel-bearing.html (https://www.leadingedgeairfoils.com/3-4-i-d-x-1-3-8-o-d-standard-ball-bearing-wheel-bearing.html)
I'd guess the 10 lbs they listed is for the 2 rims with the bearings and rear drive hub...
Leonard used plastic bushings on the prototype for bearings, no brakes. Most likely the lightest Eagle ever built.