Jared_Solomon
Well Known Member
Hey All,
i've been plugging away at my RV-14 and I've run into a snag. After installing the main landing gear and performing the toe-in/toe-out measurements it appears that my left landing gear has a twist in it resulting in 2.8 degrees of toe-in. I decided to machine myself a shim to take the twist out (I have the equipment, so why not!). I installed the shim and it went on no problem. It got me thinking about the preload I might be putting on the bolts with the 2.8 degrees of deflection. I reached out to Van's. I spoke with Gus who in turn spoke to engineering. His response was engineering felt it should be fine, but he thought it was best to replace the gear. There shipping me out a new gear leg today. As a side hobby i've been trying to learn more about mechanical engineering. So I decided to try and run some calculations of my own to see how how much pre-load, particularly in shear I am putting on the bolts with the shim. I used an online beam stress calculator to run my calculations. Am I in the ballpark?
Beam Length (Bolt Length) = 2.25
Center of the deflection = 1.125 (half way point)
Area Moment Of Inertia = 0.00019
Young's Modulus = 30E+6 * .38 (reduced for shear) = 11400 KPSI
I also ran the calculation for the full Young's Modulus of 30E+6, which brought the shear force to 0.7 KPSI.
i've been plugging away at my RV-14 and I've run into a snag. After installing the main landing gear and performing the toe-in/toe-out measurements it appears that my left landing gear has a twist in it resulting in 2.8 degrees of toe-in. I decided to machine myself a shim to take the twist out (I have the equipment, so why not!). I installed the shim and it went on no problem. It got me thinking about the preload I might be putting on the bolts with the 2.8 degrees of deflection. I reached out to Van's. I spoke with Gus who in turn spoke to engineering. His response was engineering felt it should be fine, but he thought it was best to replace the gear. There shipping me out a new gear leg today. As a side hobby i've been trying to learn more about mechanical engineering. So I decided to try and run some calculations of my own to see how how much pre-load, particularly in shear I am putting on the bolts with the shim. I used an online beam stress calculator to run my calculations. Am I in the ballpark?
Beam Length (Bolt Length) = 2.25
Center of the deflection = 1.125 (half way point)
Area Moment Of Inertia = 0.00019
Young's Modulus = 30E+6 * .38 (reduced for shear) = 11400 KPSI
I also ran the calculation for the full Young's Modulus of 30E+6, which brought the shear force to 0.7 KPSI.
Last edited: