SailNet Community banner

1 - 20 of 30 Posts

·
Apropos of Nothing
Joined
·
1,736 Posts
Discussion Starter #1
I'm thinking about adding additional padeyes to my boat for jacklines. I know I need to use backing plates on the padeyes to give them adequate strength for the job. The question is, how beefy do the backing plates need to be? Wichard sells ready-made backing plates that match the shape of their padeye bases. Are these sufficient? For some reason, I always thought of backing plates as covering more surface area than just the shape of the padeye itself. Maybe I've read too many sailing disaster stories.

Thanks!
 

·
Aquaholic
Joined
·
1,139 Posts
More is always better, IMHO; but I have no idea what would be a minimum.

I personally would not use a backing plate that is less than twice the area of the piece of hardware; but I have NO basis for that opinion, it just feels right.
 

·
Telstar 28
Joined
·
1,000 Posts
Ajari—

The thickness and size of a backing plate really depends on what equipment you're backing and what the loads are going to be like. :)
 

·
Apropos of Nothing
Joined
·
1,736 Posts
Discussion Starter #4
What do you recommend for jacklines, Dog, in terms of thickness and area?

Assuming that beefier backing plates are needed, is that something you can buy at a West Marine or is that typically custom fabrication?
 

·
Courtney the Dancer
Joined
·
3,971 Posts
Theoretically, there is probably some formula for the size of backing plates based on the anticipated load. I've found that it usually depends on how much room you have in the location below what you are installing. Bigger is better, but I've never had anything rip out and some of the "backing plates" I've seen are nothing more than washers on the bolts so I don't think you need to get too carried away with them.
 

·
Aquaholic
Joined
·
1,139 Posts
Ajari—

The thickness and size of a backing plate really depends on what equipment you're backing and what the loads are going to be like. :)
Naturally. The real question is, what sort of formula is applied? It's such a general question. A backing plate for shrouds (chainplates, essentially) certainly needs to be more robust than a backing plate for a hand-hold, for instance.

My comments were a gross generalization; and I thought I was fairly clear on that point.

OH, that last sentence sounded snippy or offended. I'm not in the least; but I can't think of a more concise way to say what I said.
 

·
Registered
Joined
·
5,607 Posts
how much room you got?
are you using wood, aluminum or SS?
what is the construction of the deck? thin, cored deck will need more than a thick solid deck
 

·
Apropos of Nothing
Joined
·
1,736 Posts
Discussion Starter #8
I'm planning on putting the padeyes on the vertical surface of the cockpit benches so that I can run jacklines along the full length of the cockpit. I have plenty of room for backing plates. The glass there is solid, but possibly thin. I hadn't ever considered using wood or aluminum, but that's probably not a bad idea.
 

·
blue collar cruiser
Joined
·
370 Posts
I use IPE (wood) for my backing plates. It's strong as all get-out, doesn't rot and is way, way cheaper than teak.
 

·
Aquaholic
Joined
·
1,139 Posts
White Oak is good too.
 

·
Registered
Joined
·
54 Posts
I've been using 1/4" thick/ 1" wide aluminum stock with good results. Obviously strong and fairly easy to cut and shape in some of the tighter areas on the boat (fabrication for the bow pulpit was brutal).
 

·
Registered
Joined
·
5,607 Posts
oak is strong but can pick up mold or mildew, so seal it well

Ipe is fantastic stuff

If you have a carpenter shop at the marina, go see what kind of scraps they have. You could use marine grade ply also
 

·
Owner, Green Bay Packers
Joined
·
1,000 Posts
Pain,
Wander down to your local metal supply shop, Alro is one that's fairly nationwide, and pick up some 1/8th inch stainless steel plate. You want what's called a "cut-off" which is basically a scrap piece. You can cut it to shape with a cut-off wheel on a grinder, a band saw, or the old fire wrench. Then round the edges nicely on the bench grinder. Drill appropriate holes and screw it up using nyloc nuts on the bottom. If I was attaching cleats, I'd mirror the outside dimensions of the cleat. Given that it sounds like you're doing padeyes, I'd double the size of the padeye base. Drill your holes through the backing plate first, preferably on a drill press and then use the backing plate as a template to locate the holes through the fiberglas. It's much easier that way.

The steel is cheap enough that you can buy extra for future projects and it won't rust or mildew as steel or wood will. Of course, I'm assuming you're bolting up to a flat surface.
 

·
Tartan 27' owner
Joined
·
5,242 Posts
Pain,
The steel is cheap enough that you can buy extra for future projects and it won't rust or mildew as wood will.
Guy,
I was not aware that wood will rust. Perhaps you meant rot rather then rust.

PainQueller,
I would check first with the folks at ICanHazCheeseBurger.com about these backing plates first. Remember the photo of the seal in front of the beached sailboat: "Dibs on the winches."
I am pretty sure that the folks over there are more knowledgeable then here...
 

·
Owner, Green Bay Packers
Joined
·
1,000 Posts
Thanks, Caleb. I edited the post. My experience has been that it's just about as easy to make a much more permanent and stronger backing plate out of the SS as it is wood. I've used both materials and found that the extra effort is worth it.
 

·
Registered
Joined
·
2,705 Posts
The steel is cheap enough that you can buy extra for future projects and it won't rust or mildew as steel or wood will. Of course, I'm assuming you're bolting up to a flat surface.
Actually, using stainless plate is even more important if the underneath surface isn't flat. A piece of wood pulled up to an uneven surface has a decent chance of cracking - SS may bend but won't yield.
 
1 - 20 of 30 Posts
Top