Registered users don't see ads

Mounting Mack Pack Bail to Boom

Discussion in 'Big Boats' started by Parsons, Jun 1, 2018. Add this thread to a FAQ

  1. Parsons


    Joined Jul 12, 2011
    548 posts, 160 likes
    Catalina 36
    US Bay City, MI
    I'm planning to install a Mack Pack bail to the end of my Catalina 36 boom to provide some end support and a place to mount a zipper-pull block for an integrated lazy jack / main cover. I would like some advice on how to mount this to the aluminum boom approximately 3/16 thick.
    Boom end with bag installed.jpg Bail.jpg
    The bail is 18-inches tall, and has two 3/8" mounting bolt holes per side on the bottom about 4-inches across. I do not expect much stress on the bail, only the pulling of the zipper, but considering that there is almost 5-to-1 leverage, I want it mounted securely. Based on other posts and dockside advice, threading the aluminum boom is asking for trouble as there are not enough threads. I am thinking about using aluminum blind nuts (rivnuts) to give more threads. I'd use 3/8" stainless bolts dipped in Tef-Gel to prevent galvanic action (which is actually minimum here as we're in fresh). Thoughts?

  2. Tally Ho

    Tally Ho

    Joined Jan 7, 2011
    1,022 posts, 143 likes
    Oday 322
    US East Chicago, IN
    I mounted the same bail on my O’Day 322 boom using the supplied screws. Drilled and tapped the holes in the boom. Been in service for 4 years and no issues.

    As you said, not much stress on the bail and with the 2 legs on each side of the boom, it is pretty beefy.


Sunbrella lifesling covers
Any color, fits over existing bag to match your existing canvas.
Flexible steel chafe pads
Innovative new product made of flexible, laser cut stainless steel. Must see!
Low prices, custom fit, no-wait estimates
NEW, updated Get Rid of Boat Odors
The bible of marine toilets and plumbing, expanded and updated for 2016!