I believe that there was a piece of plywood tying the starboard and Port wedge blocks to each other. The wedge block are screwed into the plywood, so they can't shift outward. then there are separate stacks of cinder blocks under the plywood. -Kevin Acheson M15 "Picolo" On Wed, Mar 6, 2019 at 11:01 AM < montgomery_boats-request@mailman.xmission.com> wrote:

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Date: Tue, 5 Mar 2019 11:46:18 -0800 From: John Schinnerer <john@eco-living.net> To: montgomery_boats@mailman.xmission.com Subject: Re: M_Boats: lifting a Montgomery 15 Message-ID: <0f01f0c2-d6d9-fccb-a1e2-9bfe79a91716@eco-living.net> Content-Type: text/plain; charset=utf-8; format=flowed

Just looked at the page on the MSOG site, I see that's to get it off the trailer for bunk replacement. Obviously using the bunks to support cross beams or stacked 2x6 would not work for that need. But could get it high enough to drop CB for example.

My one concern about the lifting method on the MSOG site - is there anything tying the two rear hull supports together, laterally across the hull? I can't see anything like that in the pics (but it may be there, and hidden?).

There is at least some lateral force (outward, away from the hull) on those wedges on top of those stacks of CMUs, because boat weight is on those wedges. A risk would be that the lateral force would cause the support to collapse sideways away from the hull. Even a mild bump of the boat could trigger it. Squirt the wedges out, or the whole stack of blocks goes down outwards, etc.

So I would be sure to tie the rear support wedges together. Fastening them securely to a cross-piece would do, even just a 2x6 laid flat. That way the 2x6 holds them vs. the outward lateral force. The vertical supports then feel only vertical force.

And...I wouldn't use CMUs for supports if my life depended on it, which it might if I were under or near under the boat and one failed.

cheers, John

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