Frugal Flyer
Member
Hi all,
I am trying to build a low cost trike frame (although I plan to buy the wing), and before I could cut the first metal, I have already stalled with the rear suspension.
Here are the issues:
1. I have discarded the flat Grove type spring aluminum landing gear idea as too expensive and too difficult to make at home.
2. I have discarded the Tailwind/RV type round tapered steel rod type of landing gear idea as too expensive and too difficult to make at home.
3. I am still looking the Thorp T-18 and Drifter type tapered/stacked TUBULAR landing gear idea because they can be constructed (frugally) from straight tubes.
What I like on this third option are:
1. Tubes are straight, i.e., I don’t have to deal with bending.
2. I could use multiple sizes, multiple length tubes sliding into each other to simulate a tapered rod bending characteristic.
3. I could use multiple materials (aluminum, steel and fiberglass) to further tailor the stiffness/bending properties of the assembled gear leg.
4. I may be able to even eliminate the heat treatment (the remaining expensive part of the gear), if I can achieve the required strength, bending characteristic and flexibility without heat treating.
The questions that I still have:
1. I have figured out how to calculate the individual beam deflection on each of the cantilevered beams separately, but I don’t know how put them together, ie., how to to calculate the “tapered” beam when I slide the various diameter, various length tubes into each other.
2. Even if I figure out the formula, I still want to verify the deflection by test, but how?
a. I was thinking to secure one end of the gear leg in a hole drilled in a telephone pole and lift up with a carjack the other end to observe the bending characteristic (and eventually break it).
b. But how do I know that how much force I needed to bend it and how much needed to break it?
c. It appears to me, I need some kind of a load sensor on the top of my car jack that to attaches to a laptop, but I am not familiar with sensors.
Can someone have an idea how to find a low cost, easy to use method or sensor to measure the landing gear load up to about 5000 lbs?
(If someone knows the formula how to calculate the “tapered” rod consisting multiple diameter, multiple length, multiple wall thickness, multiple material tubes and maybe a solid fiberglass rod in the middle, I would take that too, but I I find an easy way to test it, I would just build/test/adjust/test until I am happy with the result.)
Especially interested to hear from “Head in the clouds” member, who seems to know a lot of the Drifter landing gear.
Thanks, Frugal Flyer
I am trying to build a low cost trike frame (although I plan to buy the wing), and before I could cut the first metal, I have already stalled with the rear suspension.
Here are the issues:
1. I have discarded the flat Grove type spring aluminum landing gear idea as too expensive and too difficult to make at home.
2. I have discarded the Tailwind/RV type round tapered steel rod type of landing gear idea as too expensive and too difficult to make at home.
3. I am still looking the Thorp T-18 and Drifter type tapered/stacked TUBULAR landing gear idea because they can be constructed (frugally) from straight tubes.
What I like on this third option are:
1. Tubes are straight, i.e., I don’t have to deal with bending.
2. I could use multiple sizes, multiple length tubes sliding into each other to simulate a tapered rod bending characteristic.
3. I could use multiple materials (aluminum, steel and fiberglass) to further tailor the stiffness/bending properties of the assembled gear leg.
4. I may be able to even eliminate the heat treatment (the remaining expensive part of the gear), if I can achieve the required strength, bending characteristic and flexibility without heat treating.
The questions that I still have:
1. I have figured out how to calculate the individual beam deflection on each of the cantilevered beams separately, but I don’t know how put them together, ie., how to to calculate the “tapered” beam when I slide the various diameter, various length tubes into each other.
2. Even if I figure out the formula, I still want to verify the deflection by test, but how?
a. I was thinking to secure one end of the gear leg in a hole drilled in a telephone pole and lift up with a carjack the other end to observe the bending characteristic (and eventually break it).
b. But how do I know that how much force I needed to bend it and how much needed to break it?
c. It appears to me, I need some kind of a load sensor on the top of my car jack that to attaches to a laptop, but I am not familiar with sensors.
Can someone have an idea how to find a low cost, easy to use method or sensor to measure the landing gear load up to about 5000 lbs?
(If someone knows the formula how to calculate the “tapered” rod consisting multiple diameter, multiple length, multiple wall thickness, multiple material tubes and maybe a solid fiberglass rod in the middle, I would take that too, but I I find an easy way to test it, I would just build/test/adjust/test until I am happy with the result.)
Especially interested to hear from “Head in the clouds” member, who seems to know a lot of the Drifter landing gear.
Thanks, Frugal Flyer