The horns on the rudder, where the control cables attach. They take a larger shackle size, which has a 1/4" hole within. However, the hole in the rudder horn is only 3/16".
The builder manual suggests this shackle needs to be bushed, I think. Practically, this required two TINY little steel bushes at each shackle. They are almost too small to shape precisely without crushing them. Almost impossible to size correctly once paint is introduced, so it wore off quickly with fit and use...
Fast forward countless flights in the rain, wet landings, days parked outside. The bushes have corroded so badly that I couldn't get the bolts out. I had to use a hammer and feared I would bend the bolts / horns. Eventually one bushing gave way and I joggled the bolt out. I don't want to put this bolt back with the same tiny unpainted bushes.
I am tempted to drill the horns out to 1/4", although I wish I did that before I re-painted the horns yellow!
Does anyone see a problem with upsizing those holes from 3/16" to 1/4"?
All the steel parts involved are as big as they can possibly be given the dimensions of the shackle, and 4130N steel is pretty strong. So I suppose that the shackle was designed to work with a part which has a 1/4" hole in a same dimension of our rudder horn, and the strength must be about the same as our horn. There is enough steel there to take many hundreds of Newtons of force.
Thoughts?
The builder manual suggests this shackle needs to be bushed, I think. Practically, this required two TINY little steel bushes at each shackle. They are almost too small to shape precisely without crushing them. Almost impossible to size correctly once paint is introduced, so it wore off quickly with fit and use...
Fast forward countless flights in the rain, wet landings, days parked outside. The bushes have corroded so badly that I couldn't get the bolts out. I had to use a hammer and feared I would bend the bolts / horns. Eventually one bushing gave way and I joggled the bolt out. I don't want to put this bolt back with the same tiny unpainted bushes.
I am tempted to drill the horns out to 1/4", although I wish I did that before I re-painted the horns yellow!
Does anyone see a problem with upsizing those holes from 3/16" to 1/4"?
All the steel parts involved are as big as they can possibly be given the dimensions of the shackle, and 4130N steel is pretty strong. So I suppose that the shackle was designed to work with a part which has a 1/4" hole in a same dimension of our rudder horn, and the strength must be about the same as our horn. There is enough steel there to take many hundreds of Newtons of force.
Thoughts?
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