Very Small RIBs

[GandyGoose]

Hi,

First post here, please be gentle. We're thinking of getting a small RIB, around 3m, to use as a tender to our sailing boat on its swinging mooring, and for pottering around. It needs to be able to carry four people on rare occasions, two people plus luggage more often. I'd prefer Cat C, since there can be a bit of chop kicked in some places, and powerboat wash as well.

Currently we're using a 10ft fibreglass dinghy with a Merc 2.2, but that's not ideal for a few reasons. Its a bit tippy and certainly doesn't feel secure for passengers in any sort of chop. That same tippiness makes it less safe getting between boat and tender than I'd like. Then the fact that its hard means we need to mess around with fenders etc when its alongside.

Looking at some boats in the dealer, I liked the look of the Zodiac Zoom 310. The solid hull seems sensible.

Really I was wondering about the pros and cons of a RIB vs an inflatable floor boat at these sizes, and whether there were other comparable or better or cheaper models that I should look at.

I haven't even thought about motors yet. Maybe try the 2.2 and see how much more oomph it needs. The 2.2 pushes our hard dinghy fast enough to throw up a fearsome wake.

Thanks in advance for any comments,

Tony S

[codprawn]

If the boat will never be stored away go for the hard bottom. If you want to chuck it in the cabin or the back of the car go for a softie.

I have a Quicksilver 3.1m which is great - has carried 3 adults and 2 kids at about 20mph with a suzuki 15hp 4 stroke.

A 2.2hp is very small - I wouldn't go for less than a 7.5. Never kn ow when you need the extra grunt.

http://rib.net/forum/showthread.php?...uicksilver+310

I would go for a 2 stroke - much lighter.

[Polwart]

I think cod is right 2.2 HP may struggle a bit with a boat that size if the chop is bad enough to genuinely justify a cat c boat (oh oh - thats probably just started a third thread debating the value of the RCD ).

I don't think you will need to go as big a 7.5 HP though. Whilst it would be nice to think you could get the rib on the plane if you wished to do so lightly loaded - what you are interested in is getting from your mooring/anchorage to shore and back. Essentially in rib terms (or at least in terms of most ribnetters) this is just an auxilliary engine. The generally ribnet rule of thumb is 1HP per m of hull length for an aux. So a 3.3 should be OK. A bit bigger would be slightly better - but bear in mind that bigger will be more expensive and probably heavier.

In terms of hull - i think you have 3 options: (1) a totally soft bottomed boat (known as SIBs here). (2) a soft bottomed boat with floorboards (also known as a SIB) (3) a fibreglass hulled boat with inflatable tubes (what is generally considered a RIB here).

Depending how big your yacht is will influence which of these is sensible. But my experience of yacht tenders in category 1 above is that they are much less "secure feeling" than the sort of thing I think you have right now - but as cod says much easier to collapse and take with you.

Not sure if there is anyway you can try these afloat before you buy. Stepping down off a yacht can feel quite tippy in a lot of boats.

[GandyGoose]

Cheers. Your both right about the motor, and even if I didn't need more power then I would still want F-N controls at the very least. I'm happy with two-stroke. Maybe a 4 is the sensible minimum, or see what turns up either with the boat or second-hand.

Codprawn - that boat in your thread, is that a RIB, if that's not a rude question? I could only find "soft" Quicksilvers when I was looking around.

My Cat C comment was maybe a bit OTT - I just noticed that inflatables of around this size tend to be Cat C, so I guess I might question why something on offer might be only D. Our mooring could have a mile or more fetch at high tide, but I wouldn't really expect 2m waves.

[GandyGoose]

Oops should have said. I don't intend packing the boat away. It'll sit on a trolley when not in use, hopefully under cover. We couldn't fit it on board anyway, we have an Avon Redstart for use away from home.

I like the idea of a solid hull just on pure prejudice, not based on actual knowledge. Are there any disadvantages over an "airdeck" type boat, aside from a little weight and a little cost?

(I'll need to say SIB, won't I. I've only just learned to call RIBs RIBs, back in "my day" they were called Seariders, because those were the only ones we'd seen)

Tony S

[codprawn]

My Quicksilver is a SIB with a wooden floor. There is an inflatable keel which gives the bottom a sort of cathedral hull shape.Wooden floorboards are more rigid than an air floor but not as good as a true hard bottom boat.

As to coping with sea conditions we have crossed from swansea to Ilfracombe and back - something like 25 miles each way....

[Hugh Jardon]

Originally Posted by codprawn

My Quicksilver is a SIB with a wooden floor. There is an inflatable keel which gives the bottom a sort of cathedral hull shape.Wooden floorboards are more rigid than an air floor but not as good as a true hard bottom boat.

As to coping with sea conditions we have crossed from swansea to Ilfracombe and back - something like 25 miles each way....

was that a wise thing to do? in a 3.1m sib

[Polwart]

Originally Posted by codprawn

There is an inflatable keel which gives the bottom a sort of cathedral hull shape.

do you mean cathedral hull? as in like a dory?

[Polwart]

Originally Posted by Hugh Jardon

was that a wise thing to do? in a 3.1m sib

at what size of boat does that suddenly become a wise thing to do?

[edit: unless you meant - going back to Wales?]

[GuyP]

Originally Posted by codprawn

A 2.2hp is very small - I wouldn't go for less than a 7.5. Never kn ow when you need the extra grunt.

Originally Posted by Polwart

I don't think you will need to go as big a 7.5 HP though. Whilst it would be nice to think you could get the rib on the plane if you wished to do so lightly loaded

Having spent my teenage years mucking around in a varierty of SIBs, you'll need at least a 5hp to plane a 3m SIB when lightly loaded. However, when loaded and against tide you'll find the going slow and you'll chew up fuel, as you'll be giving it full throttle all the time. I'd go as big as is reasonable for your budget. There's very little difference price and weight (now they're all 4-stroke) wise between a 4.5hp and a 7.5 hp now anyway.