Norman_E
Well-Known Member
My boat has Goiot hatches that have hinges of a pretty odd design. How they work is that the "pin" of the hinge is a piece of rubber about 10mm diameter with a 5mm hole through it. This piece of rubber is compressed end-wise by a 5mm Allen screw and a tubular nut, so that it expands width-wise to provide a friction hinge. That at least is the theory. In practice after time the rubber goes hard and starts to break up leaving the hinges with no friction. In some cases the rubber has crumbled so replacement is urgent. I have a temporary fix in one with a piece of braided fuel hose.
The rubber pieces seem difficult/impossible to obtain so I propose to machine close fitting plastic replacements. The question is what plastic has the right properties. I need it to deform a little when compressed by the Allen screw. I am not looking to create friction to hold the hatches in place when open, but just to give enough friction to prevent them coming out as there is nothing to retain them end-wise.
Thoughts are nylon rod or possibly PTFE rod. I suspect that Delrin is too hard. For this job a fairly soft plastic that suffers "creep" under pressure seems indicated.
The rubber pieces seem difficult/impossible to obtain so I propose to machine close fitting plastic replacements. The question is what plastic has the right properties. I need it to deform a little when compressed by the Allen screw. I am not looking to create friction to hold the hatches in place when open, but just to give enough friction to prevent them coming out as there is nothing to retain them end-wise.
Thoughts are nylon rod or possibly PTFE rod. I suspect that Delrin is too hard. For this job a fairly soft plastic that suffers "creep" under pressure seems indicated.