Deck Anchor Points.

Nasher · 12 August 2011, 21:44

All

I know it’s been asked before, but I don’t think anyone has ever really found a satisfactory answer.

Following our Dartmouth holiday I want to find a better way to strap the Smaller Nashers 9.9 Suzi down to the deck of the RIB. Plus other 'Cargo'

This would involve having permanent anchor points in the deck which would need to be:

- Stainless steel.
- Completely flush when not in use.
- Installed without access to the underside of the deck.

My current thoughts are to weld an M10 nut to the back of a Disc of 3mm plate.
Route a 3mm deep recess in the deck with a hole in the middle to take the nut.
Epoxy the disc into the recess, plus use 4 countersunk screws to hold it down.
Use screw in eyes to lash down to that can be removed when not required.
All the above in Stainless of course.

What I don’t like about this idea is:
I’d rather not have the screws showing.
They would be a lot stronger if they went all the way through the deck with a spreader plate on the back.

I may regret this, but –Discuss.

Nasher.

Hightower · 12 August 2011, 21:49

Can't you just mount the engine on the transom of Nashers Revenge and use it as an Aux as well as for the SIB?

Nasher · 12 August 2011, 21:53

Unfortunately there isn't room to get it on the transom, and taking it on and off would make transfering the engine between boats even more of a chore.

I had hoped to do it and use it as an Aux, but had to give up on the idea.

Nasher.

Starovich · 12 August 2011, 22:12

like This?

Nasher · 12 August 2011, 23:20

Quote:

Originally Posted by Starovich

like This?

Thanks for the suggestion, but as mentioned they need to be flush with the deck when not in use.

Nasher.

Poly · 12 August 2011, 23:23

something like this Monitor Marine International might be an option if either you can put a small hatch in to access the nuts on the back or find something with a different fastening.

alystra · 12 August 2011, 23:25

I've used these Henshaw Inflatable Boats HEN 2058 or 2059, glued to the GRP deck with the two part hypalon glue. No sign of them coming unstuck despite some hefty tension on them. Haven't tried to hold an outboard down with them though.

Poly · 12 August 2011, 23:42

Nasher, what you are proposing is similar to this - Pad Eyes, Removable Eye Deck Plate, Stainless Steel, Welded & Polished (although at that price I can see why you want to DIY). Had you considered the need for a "plug" in the hole when the eye is not fitted and that makes fitting / removal a bit more of a nuisance?

Starovich · 13 August 2011, 08:04

this or
These
or This
or These

spartacus · 13 August 2011, 09:37

Quote:

Originally Posted by Starovich

this or
These
or This
or These

Good suggestion, but would need to be stainless-steel, instead of zinc-plated. A summer's use and they will be rusted through.

Starovich · 13 August 2011, 11:01

amazing what google can do
More
316 Stainless

Hightower · 13 August 2011, 11:46

I had a little think on this problem last night. What Nasher suggests is OK for asthetics and functionality, the problem lies with making sure the screws are firmly attached to the deck to prevent them pulling out of the wood.

If you could buy stainless collapsable partition wall inserts that will deform when the screws are done up and anchors the insert into the deck, then that will do the trick nicely.

The only other problem will be water ingress when not in use, so a screw in cap will have to be made and fitted when not being used.

Nasher · 13 August 2011, 15:58

Thanks for the suggestions guys

Plenty of food for thought there.

For other reasons I really need them to be completely flush with the deck when not in use.
Unfortunately Polwarts Monitor marine items look particularly good but I don't know how I'd mount them, and I bet they are a bit pricey.

I don't really want to go adding hatches everywhere to gain access to the underside of the deck, and it doesn't matter if the threaded holes are left open when not in use. The area underneath has the fuel tank in it and has large drains back into the well at the transom. Any water in the well backs up into the space anyway, so I often remove the small hatch over the sender and flush it with fresh water.

I'm thinking more about using 3inch discs with 4 screws in each point along with epoxy. With 4 points the engine would have 16 screws and a large area of epoxy holding it down which I'd have thought would be enough.

Need to do some more thinking.

Nasher.

Ian M · 13 August 2011, 19:21

So, a bit like these then?
Not much use to you unfortunately, I had blind threaded inserts put into the deck during manufacture, and finished them off with the stainless washers that you can see in these shots. They sit nicely flush with the treadmaster.
Simon, you have a PM.

Razorbill RIBs · 13 August 2011, 21:53

Hey Nasher....see my thread /solution here: http://www.rib.net/forum/f8/removeab...how-32701.html

We bolt in survey kit, seats, bottle rack, have used them when we have had custom brackets fabricated for tripod mounts etc.....The dowls work brilliantly and haven't budged. We use flush allen headed blanks when not in use greased up with silicon grease. They aren't 316 so I occasionally give them a light wire brush and spray with wd40...they still look like new. Can get you some pics this week if you want.

Am going to do something similar for the Pac, but am able to access beneath the deck there so might just go for the bighead solution.

Dan

9D280 · 15 August 2011, 10:06

Somewhere on the SIB pages I mooted my idea of using Yacht / dingy jibsheet lead block tracks & then using the travellers that have a simple eye on.

The plus points are that you get a rail that is granted not flush, but pretty close & eminently walkable on, and also means that by using the travelelrs you can have as many and in almost infinitely variable positions along the deck. Traveller cars can be removed when not in use.

My plan was to fit them along the corner where the deck joins the hull, but that's a feature usually only found on Seariders & some Humbers.......

Nasher · 09 September 2011, 21:14

Just a little taster of what I'm up to with this project

As you can see a Prototype has been knocked up.

So far I've managed to blag all the materials as other peoples waste. Although I had the Stainless M12 Acorn Nuts 'In Stock' from another project.

The Two 2mm plates are plug welded together and the Nuts welded on the back.

I know the water that gets in the hole will just sit there, but I'm happier with that than it draining down through the deck. In any case a quick blast with the pump will get most of it out.

More to follow.

Nasher.

Razorbill RIBs · 09 September 2011, 22:18

Looking good Nasher, v. similar in principle to ours

....... When not in use, we have recessed allen headed /threaded inserts which are flush and help keep the threads clean.....I lube them with silicone grease.

martini · 10 September 2011, 12:17

Quote:

Originally Posted by Razorbill RIBs

Looking good Nasher,

+1

Although I'm interested to know why one plate has 3 big holes when the others have just one in the centre? And why another has much larger diameter csk holes??

Poly · 10 September 2011, 13:10

Quote:

Originally Posted by martini

+1

Although I'm interested to know why one plate has 3 big holes when the others have just one in the centre? And why another has much larger diameter csk holes??

Ah, I'm glad a professional is asking that - I thought I was just being thick! I guess the difference in diameter of the csk holes is because the two plates are stacked together to get the total thickness hence the top plat has a bigger csk than the bottom? Are the 2 big holes something to do with how the two plates are welded together?

[Edit: Ah - just looked up what plug welding is - and it sound like my guess was about right. Sounds like a lot of effort compared to finding some 4mm plate in the first place?]