SailNet Community banner

1 - 20 of 26 Posts

·
Registered
Joined
·
163 Posts
Discussion Starter · #1 ·
I am looking at converting my boat to have the lines run to the cockpit. Most of the hardware doesn't come with backing plates but I know you should use them to distribute the load. I also don't see much in the pre-fabed variety either. What do you use?
 

·
Remember you're a womble
Joined
·
2,328 Posts
Depends on the loads you're expecting, and what you are fitting it through. Sometimes I just use a big washer, sometimes a plate made from 3/16th stainless, sometimes a bit of half inch marine ply.
 

·
Registered
Joined
·
163 Posts
Discussion Starter · #3 ·
Do you have any good sources for the 3/16th stainless?
 

·
Registered
Joined
·
3,184 Posts
If it's hidden, large washers or starboard. If it's visible in the cabin, stainless steel sheet because that's what Bristol used at the factory.

Mc Master Carr for the stainless sheet. I use it for backing plates and stuff like the extra instrument panel below :



 

·
Learning a bit every day
Joined
·
214 Posts
As mentioned before, it really depends on the loads on them. I am also not combining different metals, in order to reduce the risk of galvanic corrosion. You can get pieces of 316 steel here on fleebay cut to size. Much cheaper than what the stainless shop close to where I work would charge. I've also used large stainless washers, Nylon washers and as I cannot get StarBoard in the UK, HDPE chopping boards.
 

·
Registered
Joined
·
765 Posts
I'd use 3/16" G10 Garolite from McMaster-Carr.. You can cut it with most saws (yes, it will ruin the blades) and drill with any drill. It is stronger in compression than Ssteel and will not cause any corrosion.
 

·
Senior Moment Member
Joined
·
13,290 Posts
As you can see from Marksf's post, polished S/S with acorn nuts is the best looking. I prefer to use it or fender washers (on lower loaded hardware) in areas where the backer is visible. Save the Starboard/G10 etc. for the hidden stuff.

Polished S/S is definitely the most work but it looks the best by far and you're only doing it once.

Unless you have a drill press and a band saw with a metal blade I'd strongly recommend getting them roughed out by a machine shop - they can flame/laser/cnc cut the pieces and punch the bolt holes instead of drilling.

File & sand to 1200 then polish them on a $40 Harbour Freight polishing wheel.
 

·
Registered
Joined
·
541 Posts
The backing plate is only one component – you must also think where you are positioning the hardware – some places have balsa core which cannot take the compression when you tighten the bolts. If this is the case you’ll need stainless spacers to put the bolts inside – they will take the load without damaging the deck. And don't forget the butyl....
 

·
Bill SV Rangatira
Joined
·
421 Posts
The backing plate is only one component – you must also think where you are positioning the hardware – some places have balsa core which cannot take the compression when you tighten the bolts. If this is the case you’ll need stainless spacers to put the bolts inside – they will take the load without damaging the deck. And don't forget the butyl....
remove the core around the bolts and fill with thickened epoxy to prevent compression use a countersink to allow butyl to form O ring around the bolts
my $ 0.02
 

·
Registered
Joined
·
3,264 Posts
Starboard, and cutting boards are not sutable for backing plates. The plastic they use is junk, and will deform under light compression loads applied for any length of time. I don't know who first thought of them, but it is a terrible idea.

The prefered is either a stainless plate, which should be available at almost any metal shop for a couple of bucks, or G10. G10 is a fiberglass board made under high pressure, and is extremely strong. It does tend to ruin blades, but bi-metal or carbide blades work ok. Just go slow since the board won't disperse heat like cutting into metal will.
 

·
Registered
Joined
·
7,861 Posts
I'd use 3/16" G10 Garolite from McMaster-Carr. It is stronger in compression than Ssteel and will not cause any corrosion.
I don't believe G10 is stronger in compression than stainless steel.

Corrosion? The nuts and bolts will be stainless as well so no problem there.
 
1 - 20 of 26 Posts
Top