Mast and boom capacity

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.

PNWPederson

Veteran Member
Joined
Apr 24, 2024
Messages
35
Location
Bellingham, WA
Vessel Make
1970 Grand Banks 32
Does anyone know the capacity of the mast/boom of a 1970 GB 32? I'm curious if I could hang a hammock from the boom to sleep in. Has anyone ever done this?
 
In 100% pristine condition?
This is guesswork. I will guess it will hold 250 lbs, probably more.
The weak link is the pulley at the top of the mast which no one services.
 
I think it 350# on a 36. Depends if wood or aluminum. Personally I limit mine to around 100#. Have hung a hammock off ours and a really secure railing.
 
I never trusted the 1972 wooden boom and mast rig on my 1972 GB42. Before I would hoist the inflatable and OB motor combo on it, I rigged what we in the Navy called "preventers." I also had a new SS mast collar made where the topping lift pulley attaches to the mast (photo 2). You can see the wire rope preventers rigged through the straps of the pulleys which gives backup in case attachment point or shackle fails. For pulley failure backup, you could run the cable clear around the pulley and between the two parts of the line running in and out of the pulley. Don't bet your noggin on the rig to support your weight. It was never designed for that. Safety factors (how many times the rated weight the rig can support) for humans are usually 3-plus meaning to support a 250-lb person, the rig should handle 750 lbs if the factor is three.
 

Attachments

  • boom preventer.jpg
    boom preventer.jpg
    71.4 KB · Views: 28
  • dscn2344.JPG
    dscn2344.JPG
    94.1 KB · Views: 21
Last edited:
On a sailboat, a preventer is a line temporarily attached to the boom
or a poled-out sail to keep or 'prevent' it from an inadvertent gybe.

Yours appear to be a safety back-up in case the shackle works loose or fails.
The stainless collars appear nicely robust. (edited)

Film and TV electricians and grips use the same item they call 'lanyards' for safety.
 
Last edited:
On a sailboat, a preventer is a line temporarily attached to the boom or a poled out
sail to keep or 'prevent' it from an inadvertent gybe.
Yours appear to be a safety back-up in case the shackle works loose or fails.
The stainless collars appear far more robust than the preventers and if the ends of
the wood spars were to carry away then the preventers would likely go with them.
I agree, but I never distrusted the spars themselves because those things were built to last. If conditions were such that the spars gave way, the whole boat was going down.
 
Back
Top Bottom