Quandary
Well-known member
I have a Volvo three blade folding prop. The pivot pins for the blades are kept in place by three socket headed stainless steel machine screws which are screwed in to the bronze boss. They are located in small recesses so only a socket headed bolt will do. When I take the prop apart each winter to grease the pivot pins I put them back with some threadlock. This year I can not get two of them out with an allen Key, The sockets are quite a loose fit for a 5mm. allen key but just too tight for a 5.5mm. one, so when I try to apply torque the key eventually skids out. I have tried using a key from a socket set to get a straight drive but they seem only to be available in 5mm or 6mm. sizes. and not that high quality, I have a set of imperial allen keys in intervals of 1/32 but can not find a tight fitting one there either. Part of the problem with ordinary keys is that it is very difficult to apply enough torque while keeping the things straight and they cut the hands off you. I am puzzled by the poor fit or do Volvo use a special key of their own size, the sockets in the heads are not damaged, yet!
I am sure real engineers have a solution for this but I have got away with ordinary keys until now.
Or is it a waste of time greasing the bearing surfaces and teeth on folding propellors, I presume the grease soon washes off anyway to be replaced by water lubrication?
I am sure real engineers have a solution for this but I have got away with ordinary keys until now.
Or is it a waste of time greasing the bearing surfaces and teeth on folding propellors, I presume the grease soon washes off anyway to be replaced by water lubrication?
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