Specifications help

[Tbride]

I recently bought a 2004 Mac 26M with a broken mast. The new mast is in place but there is a nagging doubt in my mind about how high from the deck, from the bottom mast plate, to the gooseneck for the boom should be located. We tried to carefully match the old mast, but it seems a little too low. When the dodger is on, the back end of the boom wants to rest on it. Is someone willing to give me a measurement of where their gooseneck attaches to the mast?

Clarification: The new mast from Blue Water Yachts had no holes drilled in it.

 

[Justin_NSA]

If no one here can help. Try BWY. They may have the measurements. Is the new mast a direct (rotating) replacement?

 

[DrJudyB]

There are two more more things to check, in addition to the height of the gooseneck above the mast foot.

1. The rake of the mast has an effect on the height of the boom end. The mast on the 26M should be raked 4 degrees aft. Every xtra degree of rake drops the end of the boom by about 2.15 inches. The boom should be horizontal when it’s 86 degrees to the mast.

2. Of the sail is very old, the bolt rope in the luff ( front edge) may be shrunken. This makes the luff look very wrinkled and baggy, and, more important to this discussion, it makes the back end of the boom droop and perhaps hit the Bimini.

Judy B
Retired sailmaker who worked a lot with MacGregors.

 

[Tbride]

If no one here can help. Try BWY. They may have the measurements. Is the new mast a direct (rotating) replacement?

Justin,

Thanks, Blue Water Yachts does not have that particular measurement in their specs and they are out, mostly, during the pandemic; except for order fulfillment.
It is the rotating mast.

Best,

Terrence

 

[Tbride]

There are two more more things to check, in addition to the height of the gooseneck above the mast foot.

1. The rake of the mast has an effect on the height of the boom end. The mast on the 26M should be raked 4 degrees aft. Every xtra degree of rake drops the end of the boom by about 2.15 inches. The boom should be horizontal when it’s 86 degrees to the mast.

2. Of the sail is very old, the bolt rope in the luff ( front edge) may be shrunken. This makes the luff look very wrinkled and baggy, and, more important to this discussion, it makes the back edge of the boom droop and hit the Bimini.

Judy B
Retired sailmaker who worked a lot with MacGregors.

Dr. B,

Wow, thank you for the detailed and fast response.

Terrence

 

[Benny17441]

Having the boom rest on the bimini is largely a function of the "topping lift". Set the gooseneck at the point where the Luff of the sail adequately tightens and then adjust the topping lift to create an angle where the boom clears the top of the bimini. If unable to synchronize both adjustments the bimini is improperly sized. Always give preference to being able to tighten the Luff. Some will cut the sail and sacrifice sail area for shade.

 

[timebandit]

boom sag

i have just bought a mac 22 and have rigged it, however my boom sags alot with out the sail run up tight. is that normal or will i have to make repair before heading to the Bay

forums.sailboatowners.com

Some spirited conversion on your problem maybe

 

[timebandit]

boom sag

i have just bought a mac 22 and have rigged it, however my boom sags alot with out the sail run up tight. is that normal or will i have to make repair before heading to the Bay

forums.sailboatowners.com

boom sag

i have just bought a mac 22 and have rigged it, however my boom sags alot with out the sail run up tight. is that normal or will i have to make repair before heading to the Bay

forums.sailboatowners.com

Some spirited conversion on your problem maybe