Bolting a rack down on the floor of an Avon RIB

[dsteding]

I have an 5.6m Avon Adventurer, and I'm adding a scuba tank rack.

I'll need to bolt it to the floor, my question is, what is the best way to go about it?

The back rack (installed by the previous owner) has brackets lag bolted in place. I could do that, or I could use a sleeve-type anchor ("molly bolt") that would allow everything but the sleeve to be removed.

Thoughts?

Also, anyone know how thick the deck of an Avon hull is?

[matt h]

one inch thick,

[Nos4r2]

Originally Posted by matt h

one inch thick,

I remember you saying yours was that thick, but didn't Avon argue the toss over that and say it shouldn't be (making yours an exception) or something odd like that??

[Stoo]

In my last RIB, which was about 5.2m, I bolted a Pelican rack to a 3/4" thick piece of ply, which extended 6" or so past the rack. I notched this ply so that the centre console slipped into the notch to hold it in place. This plywood base was a few inches larger than the rack for stability.

I found the rack to be very stable, but I could also remove the entire thing easily when I wanted an uncluttered foredeck.

I'm assuming you are talking about this type of rack...

[dsteding]

Originally Posted by Stoo

In my last RIB, which was about 5.2m, I bolted a Pelican rack to a 3/4" thick piece of ply, which extended 6" or so past the rack. I notched this ply so that the centre console slipped into the notch to hold it in place. This plywood base was a few inches larger than the rack for stability.

I found the rack to be very stable, but I could also remove the entire thing easily when I wanted an uncluttered foredeck.

I'm assuming you are talking about this type of rack...

No, I'm having a custom made one out of aluminum. See the attached sketch, it the front part (where the corners on the bottom are cut off) will bolt on the anchor locker, then I'll bolt down the back.

Since we dive double tanks a fair amount we need stuff like this to support those tanks.

[dsteding]

Originally Posted by matt h

one inch thick,

Seriously? If so, I'd almost have to lag bolt it-I don't think molly bolt or toggles would work that well.

For what it is worth, the back rack is lag bolted in place-and has handled up to ~200 kg just fine.

[Rogue Wave]

Matt when you say the thicknes was an inch was that for an Adventurer or a Searider?

I believe the Adventurers are moulded by these people. it might be worth contacting them re thickness and fittings they might have a plan? and you could find some strong points

Fletcher Boats,
Macrome Rd,
Blakeley Green,
Wolverhampton,
West Midlands,
United Kingdom
WV6 9HD.

Phone: 0845 230 5670
Fax: 0845 230 5671
Email: fletcher-boats

[Stoo]

Originally Posted by dsteding

Since we dive double tanks a fair amount we need stuff like this to support those tanks.

Gotcha... as do I. I dive alone most of the time, so just lie the tanks on the deck. I'd love to see photos of this rack when it's finished...

[Pete7]

I have always used epoxy resin and GRP cloth to hold bottle racks down, assuming the rack has feet. Use an area say 8 x 18" and eight layers of cloth. Good surface preparation before hand with an angle grinder so the epoxy can grip the deck and once set lightly sand and wash to remove the bloom then paint as sunlight can degrade exposed epoxy.

Pete

[dsteding]

Originally Posted by Stoo

Gotcha... as do I. I dive alone most of the time, so just lie the tanks on the deck. I'd love to see photos of this rack when it's finished...

Sure, I'll post photos of both the front and rear racks when they are all done.

The rear rack used to hold 8 tanks, but that was just too much weight in the back of the boat (the exhaust port of my outboard would be submerged with all that weight in back). So, we're doing this to shift weight forward and balance things out.

When done, I should still be able to carry the same load, but it will be much more evenly distributed.

[captnjack]

1) Let's see if we can measure the thickness of the anchor locker wall with calipers.

2) If the back floor was think enough for the 8 tank rack, I'm thinking the forward floor will be thick enough for a 4 tank rack.

[Chris]

Why not get some top hat fittings made like the ones I had done for mounting my rear bench seat.

http://rib.net/forum/attachment.php?...2&d=1177191945

I got 6 x 3" dia disks of 3mm Stainless then had a 30mm long piece of 20mm dia. stainless roundbar welded onto the center of each disk.

Then each disk had a hole drilled and tapped for a 10mm SS bolt going through the center of each disk and into the roundbar to a depth of about 20mm leaving the roundbar sealed off at the end.

Then each disk has 4 x countersunk holes drilled around the disk that are sized to take no12 CSK SS self tappers.

Then you just drill a 25mm hole in the deck to take teh roundbar and the 4 holes for the self tappers and screw the whole things down with lots of Sika.

Very strong and worked a treat !

[dsteding]

Looks like the floor up front is ~20 mm thick. Fiberglass and plywood.

We lag bolted the rack in place, I'll post some pics when I take them this weekend.

Took the boat out and moving ~100 kg of tanks forward really helped in terms of the way the boat sits in the water.

[dsteding]

So, here is the final product, it works great, wish I could say the same about my outboard.