Advice on fixing hinged ladder to swim platform

[shoc]

Can I ask for some advice on fixing a new swiveling ladder to a fibreglass swim platform. see pictures below.

What is the best way to secure the ladder to the fibreglass? the platform is not hollow so I can't access the inside to fit in timber backing, so do I just simply screw in with appropriate sized stainless self tappers and seal with butyl tape?

 

[greeny]

Self tapping screws are probably not the best solution for this as they won't provide a solid enough fixing under normal circumstances, Just to clarify the problem, is the platform hollow but you have no access to the space, or is it solid. If so what is filled with?

 

[Stemar]

From your pics, I can't see how the ladder will get to vertical when lowered, which you need to be able to do to get back on board from the water,

However you do it, think about how you can release it and get it down from in the water.

Mine used to have a small fender tied across it to protect the flubber when we towed it. It was great until I had a Tom & Jerry moment trying to get from flubber to boat. The only way to get rid of the fender was to cut the line, but my knife was in my trouser pocket and I was wearing full oilies. Had the water been cold or had I been single handed, it could have been very nasty, and I've been a bit of a fanatic about this ever since.

 

[shoc]

Self tapping screws are probably not the best solution for this as they won't provide a solid enough fixing under normal circumstances, Just to clarify the problem, is the platform hollow but you have no access to the space, or is it solid. If so what is filled with?

I have no access to the space so I'm assuming that its hollow, so very unsure now how to do the job.


Here is a pic of a similar arrangement, where the ladder swings down but I can see what you mean by not being able to reach to swing down the ladder and even then, possibly getting bang on the head when the ladder falls. I may instead get a telescopic ladder which would fit flat to the platform and the final rung could be pulled out from the water.

 

[greeny]

Ok, so regardless of the type of ladder you fit, the problem is fixing it to the platform with an inaccessible space below.
Easy answer is to find the bulkhead inside the boat that stops your access and fit a small circular watertight hatch in it to allow access. Then you can fit decent load spreading plates/washers under the mounting. If this is not possible then you have to look at either glassed in nuts in the deck, or the type of nut that crushes up on itself to self fix in the deck neither of which are ideal or 100% secure. The other option would be to make larger spreader plates for each fixing, attaching the ladder to these and then use CT1 (or similar) adhesive plus self tappers to fix them to to the deck. The larger area will give better adhesion and the scope for more screws.
If anyone's got a better solution I'd be interested because I've had similar issues myself.

 

[Stemar]

One way would be to drill right through the platform and epoxy some metal tubes through, finishing flush with the surface both ends. Bolting through the metal tubes with penny washers either side would give all the strength you need and the epoxy would keep the water out.

They would need checking every for crevice corrosion few years.