Half-Baked Mounting

[kb79]

I'm looking for a place to mount my liferaft, and am considering mounting it on the cover for the sliding companionway hatch.

The hatch cover is 1/2" thick. However, there's almost no clearance between the hatch and the hatch cover. My thought was to get a 1/8" backing plate and weld on threaded posts - then route out a 1/8" recess so that I can place the backing plate and still have it flush with the rest of the underside of the cover.

The other problem is that right now the hatch cover is secured with only self tapping screws. A friendly dock mate suggested I just use 5200 to set the whole thing in place, and "that sucker won't go anywhere". I tend to agree, but figure I'll never get it off again. Through bolting it might be possible, but would be a huge chore with the headliner where it is.

So, two questions:

1. Do you think a 1/2" hatch cover that's routed down to 3/8" is strong enough to hold the raft against a boarding wave?

2. How 'bout this 5200 idea? Is it strong enough, and can I ever get it off again?

Thanks in advance for the help.

[James S]

The 5200 is a very bad idea....the hatch cover should be removable.
Mounting it to the hatch cover sounds to be problematic.
I would consider mounting it over the hatch cover on a couple of "bridges" that would span the cover and mount to the cabin to on either side.
This bridge could be made from SS pipe.

[Drew13440]

The 5200 is a very bad idea....the hatch cover should be removable.
Mounting it to the hatch cover sounds to be problematic.

Agreed. If there are through bolted handholds already on the cabin top, there is your answer.

[rebel heart]

Don't ever listen to the 5200 guy again.

It sucks but you need to fabricate something rather trick to make it fit well. The lift raft is heavy so you need it to be fairly secure. You could go wider and put some padeyes to the side of the hatch cover perhaps, and secure it down with some good line. I don't know the dimensions you're talking about, but handrails are normally just barely in there so anything that's truly load bearing needs to be thru-bolted. Backing plates depending on the thickness of the material you're going into (and the size of the washers underneath).

[kb79]

what if i put the 5200 in as shown in the picture - just along the seam that i have access to, but not under the lip of the cover. if applied like this, i'm guessing i could get it off with a razor blade...

it'd be a challenge to apply this precisely, and i've got some concern that it wouldn't be strong enough.

one last ditch hope, before i have to do something expensive or hard

[James S]

I would not do that...

[anjou]

Jus suppose you did mount to the hatch cover and a wave caught hold of the raft and ripped it off with the cover, then you would lose the raft and have no way to stop water entering

The failure of one item or component should never allow or give rise to a chain reaction or failure of other systems or components

[fishwife]

I'm in agreement with everything that's been advised here. It's often a good thing to look at any modification you consider making, though the eyes of a potential buyer. If they are likely to say 'OMG, that's going to cost a fortune to put right.' don't do it.
As for 5200, I spit on it, cast it into the fiery depths of hell. The only way you remove something bonded with 5200 is destructively.

P.

[kb79]

hahaha!!

ok, thanks guys. both for the good advice and for the morning laugh

[kb79]

i think i mighta figured out how to through bolt that hatch cover.

assuming i can do that properly, what do people think of the strength of 1/2" fiberglass routed down to 3/8?

is that enough to hold the raft against a boarding wave if the cover is through bolted?

[SaltyMonkey]

I highly recommend that you get yourself a valise version of the liferaft. There is no guarantee that a wave or a roll will not take it off, snap / twist the cradle, or pop it open sending said liferaft byebye. The general impression these days is that a cabin or deck mounted life-raft is dubious no matter how it is bolted down.

As backup, perhaps you could mount it somewhere closer to the cockpit. I've seen liferafts mounted near the transoms. Can't say I'd feel comfortable there either, but alas at least its closer for you to manage.

although people dont mention it, 5200 will come off but it takes a lot of grinding work and chemical action and a LOT of time for little result. It will also deteriorate given enough years and sunligt. But its a piss poor solution and should not be considered.

[rebel heart]

The amount of Cetol and 5200 onboard a vessel are inversely related to the seamanship of the owner.

whistling...

[SaltyMonkey]

5200 will not save you. neither will seamanship.