I had my boat surveyed in June 2019 for insurance purposes (20 yrs).
The surveyor called in advance to advise me that he would be checking the keel bolt torque with his torque wrench but it was my responsibility to ensure I had an adaptor for his torque wrench with 1/2" drive. If I did not have one, he would be more than happy to supply a fabricated one for a reasonable cost. Looking into my bilge, I could see exactly what he was getting at.
View attachment 173525
The threaded portion on that one bolt is 6" long and a radial space of 2-3" to swing a cat. Not ideal for a torque wrench given that the bilge is 12" deep.
Given some welding gear and a few spare sockets, I fabricated a 16" long adapter with a 1-1/4" pipe in between the two sockets and then promptly forgot to photo the thing for my records
. Next project.
Required torque values came from Marlow Hunter which were also the maximum allowable for that size of SS stud.
View attachment 173527
I was then able to show the surveyor that all six bolts withstood the required torque without movement. I was able to get under the table easier that the surveyor so I was elected to the job.
Unless the owner is fully knowledgeable about his boat and can discuss it with the surveyor needing the test, I would suggest the surveyor needs to make an initial visit to see what he's dealing with and if an adaptor needs to be fabricated.
I couldn't come up with a "universal" adapter to patent which would cover all scenarios so there went my dreams of an early retirement, up in smoke. You'd pretty well need a trailer full of adapters to fit every nut size, every bilge depth,every bolt length, and allow for every corner needed to be negotiated around. I've got my adapter and that's enough for me.
