help building custom ladder for '84 glastron t-161 (pic added)

[fjohn]

Hi, I've been searching the board for clues as to if this would work but find the need to post my question. I've been through the boat restore/build section wow lots of info.

I want to make a hinged tree ladder for my boat and I have a good design in mind, it's just looking at mounting it, there just isn't much there for strength. My thoughts are to brace on the inside back near the top with either 2x pt wood or aluminum bar stock ran horizontally to fasten the brackets/bolts through that would carry the ladder and have a post going horizontally from the ladder with possibly a 3" or so teflon or poly surface that would rest against the lower edge of the transom in the down position. This would hold the ladder at a slight angle. I'm thinking a 2 or 3 step ladder with the bottom step about a foot or so below the transom.

My concern is that there is only fiberglass on either side of the motor to fasten to, and I don't want a chunk of that breaking out.

I'd move it to the front or side if that would be better, but still there is only fiberglass to attach to.

Ideas? Advice?

Fred

[Bond-o]

My thoughts are to brace on the inside back near the top with either 2x pt wood or aluminum bar stock ran horizontally to fasten the brackets/bolts through that would carry the ladder and

Ayuh,... Usually, as large a piece of 3/4" plywood as reasonably Fits, as a backer is More than sufficient......
But,...
With Pictures,... The quality of your answers gets Better....

Welcome Aboard Fred,....

[fjohn]

ok, here's a rough photoshop of the plan.

[Bond-o]

Ayuh,... Due to the angles cast into that area,...(Angles = Strength)
I'd think a 1/2" plywood backer would be More than sufficent....

[fjohn]

Ayuh,... Due to the angles cast into that area,...(Angles = Strength)
I'd think a 1/2" plywood backer would be More than sufficent....

seems to me that any kind of wood backer on this, since it will be getting a lot or repititious torque from climbers, might fail unless there is metal of some kind for the bolts washers to go against on the inside. 1/2 inch ply doesn't sound to structural, especially if some 250# buddy wants to climb in. I do hear you about the angles, but 1/2", I couldn't do it. Maybe 3/4 with a metal plate to back the washers and cut to fit and hit as much of the fiberglass on the inside as possible. I'd be more comfortable with that. That's where I'm leaning now. I'd also machine the washers on the inside to sit flat so that the transfer of weight is complete on the surface. That's why I was thinking aluminum bar stock on the inside... I could just drill the mounting holes in the bar stock (recess and use stainless allen head bolts) at the correct angle to make good contact or/and machine an angle on the bar stock to fit the angle of the hull correctly and give good contact to the bracket on the outside.

[Bond-o]

Ayuh,.... Are you an Engineer,..??
It sounds like your designing something for 1 Ton loads, rather than a couple hundred pounds...
But,... Hey, it's Your boat,.... Do it anyway you'd like...

and use stainless allen head bolts)

The Highest loads are going to be on those bolts,+ SSteel is as Soft as there is....

[fjohn]

I just have no clue about fiberglass. I'd rather way over build than under build and worry about or have hull failure. It sounds like the fiberglass should be able to take the stresses of the ladder if I do my part of a bit of re-enforcing. So, I'm going ahead. Thanks. It'll be a bit, but I'll update when I get it done.

[a70eliminator]

I would re-think the whole plan, it's going to be worthless without some type of hand rails you can pull on. There are some excellent designs out there, a small platform with handrails, angled supports attached to the transom to take the weight then mount your tree ladder to that.