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Old 07 December 2004, 13:03   #1
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Buying a new RIB - Colin Jones

Buying a new RIB
by Colin Jones

Make sure you know what you are buying! Advice about buying new comes from Colin Jones, author of Rigid Inflatable Boats, with seven questions to ask your friendly RIB dealer. < Edit: This article was one of the first things on RIBnet at the beginning in January 1998! JK >


1 What is the background of the construction/marketing company?
Most builders are their own sales force, or have an officially appointed, soundly established agent with a properly equipped demonstration boat. The ones who bother my bank manager most are those who have changed company names and locations a couple of times in the past few years. they have left behind them a trail of unpaid bills, dishonoured cheques, deposits taken but no boats delivered and even have county court judgements against them. These few bad eggs seem to go down the financial Swanee, then rise again like a Phoenix from the ashes. They are well known in the trade and most honest dealers will steer you away from them, their products and their marketing consultants.
Happily there are some companies which have been trading in the leisure market for a number of years and you can deal with them with confidence. This is not to say that all their boats are equal, but they are what the author sincerely believes to be fair traders.

2 Who makes the tubes and how are they fitted?
Of the RIB's two parts, the hull is usually so solid that it will withstand many years of abuse without complaint. the inflatable element however, is more vulnerable and can give trouble in itself and in the join between the hull and sponson.
The best sponsons are those which are shaped by template exactly to fit the curves of the boat in both the horizontal plane and in the sheer to the bow. Some companies make their own shaped sponsons, whilst others contract the work out to a tube specialist -- generally Henshaw, whose reputation for quality is quite deserved.

The type of construction to avoid is that where the two sides are joined together at the nose to make a simple V-shape. This collar is then inflated to a very high pressure, attached at the bow, then forced onto the side of the boat by a couple of gorillas, whilst the brains of the team puts on some tourniquets. The ensemble is left to cure for a couple of days before being released to an unsuspecting customer, who does not appreciate that they might have bought a problem just waiting to happen. Ask.

The actual material is not a problem. Much of the Hypalon/neoprene used comes from the same source and there are quality builders who prefer military spec polyurethane. Both are good.

The best hull/tube joints are where the sponson is dropped down into a flange, which is shaped to the circumference of the tube itself. It is part of the RIB design philosophy that a sponson should give a little on impact with wave or wall, so the flange need not be enormous. it does, however, need to be adequate. A builder should be able to give you the exact dimensions.

3 How is the deck/floor constructed and supported?
This is the area where most change is happening. There is nothing wrong with the old way of supporting the floor on two or three fore and aft stringers, with lateral supports beneath the seating console, as long as the timbers are glassed over. If the long units are shaped up into an elbow which is itself glassed into the transom and to the after edge of the deck, you have a construction which is almost indestructible.
Also good is the practice of decreasing the weight without sacrificing strength and rigidity by constructing the cross members of a polystyrene former covered by a thick GRP layer.

The way of the future probably lies in propping the floor on a computer designed, plastic box form honeycomb matrix. This is already in use and has a number of pluses. Each unit is precise to a millimetre, so it should overcome the problem (very prevalent in shoddy boats) where the deck does not quite touch the propping up members, so it either cracks when subjected to the banging weight of people, or it warps and in some cases puts sufficient pressure on the hull to cause cracking. The honeycomb could also be tight enough to form a number of watertight boxes -- possibly even to house the compass sensor and isolated in-hull speed and depth transducers -- and would certainly be a very fine support for seats, dive bottle racks and A frame.

4 How is the transom configured?
After the deck, the transom is obviously the most important solid element and must be robust enough to stand the thrust of the engine. Transom support methods vary from the strong elbows already discussed, (make sure that they have drain holes to let water drain from the corners) to diagonal stainless steel bars which, I confess, are not my own favourites partly because they snag ropes and catch on things.
Good transoms are made of two separately glassed and bonded thicknesses of marine ply, solidly supported. An interesting and very sound design is used by Osprey, who use twin sloping box construction transom knees. One acts as trunking for the cables and the other is a small personal effects locker.

A water draining well just forward of the transom is more complex and costly to construct, but brings the advantages of extra floor/transom rigidity and collects all that irritating water which comes in on feet and swills around the deck to annoy dry footed passengers. The well also means that it is simpler to insert the bolt holes for engine mounting.

All hulls eventually get some water in them -- condensation, seepage through bow eyes, console fixing bolts etc. It is not dangerous, but is better removed, so I prefer to have the excavation bung egressed into a well rather than touching the sea outboard of the hull.

5 What fittings are standard?
There is often a substantial difference between what is shown in the brochure picture and what your basic price brings to the factory gate. Rubber grab handles are essential, not so much for passenger comfort, but for moving the boat and trailer on land. We were recently appalled to learn of a boat with no basic grab handles (4 is the minimum) included and to be told "Fitting them would only cost you an extra £100". I get fed up with being told that something basic will only cost X pounds to add to an already expensive product.
the areas to ask about here are not the obvious seating and steering, but such things as lifelines, bow eyes, ski hooks, double cladding on the topsides, stainless steel console rails, battery stowage, transom capping and non-slip floor. These are all relatively low cost, but tot up to a considerable budget of extras. Other areas marking generosity from penny pinching are the inclusion of good quality inspection and access hatches and the addition of an anchor locker. Here, caveat emptor because what is often described as an anchor well is no more that a transverse piece of timber to stop the anchor sliding back down the boat.

6 What sort of organisations buy your boats?
If this is important to you, make sure that you get the full story. Claims that RIB companies sell to very prestigious customers can mostly be taken with a pinch of salt -- with the exception of long established companies like Avon and Tornado, who have passed all the tests and build to stringent military specifications and controls.
Very often, the public service purchasing agent has little experience of RIBs (he also buys vehicles, specialised equipment, buildings and the fuel contract) and is very influenced by his budget and shopping around for a good deal. There has certainly been one public body who bought what experts would consider to be one of the worst boats on the market and plenty of other dodgy deals. The answer to those who say "we supply this and that police, fire, airport, coast service body" is to say "So what does that prove?" If you know the full story, often not a lot.

7 Package deals or separate suppliers?
There is no real budgetary problem here. The professional will always get a better price for trailer, A-frame, engine, navigation gear, radio etc than you will obtain. It might make you seem a bit of a pain, but you could ask what each of these elements costs to add and then compare this price with the rrp, or discount prices in magazine adverts. Some builders add a big percentage (other than for fitting) whilst others are content to pass on the savings in order to sell a boat.
A word of caution here about engines. Ask about arrangements for the essential 10 hour service. Can it be conveniently done close to where you live and without hassle. If not, you might be faced with a 200 mile drive to get it done.

Summary
Ask the same questions about what the warranties actually cover. Does a 10 year warranty on tube material also include seams and seam tapes? What happens if you sell the boat? Does a 2 year engine warranty cover the electrics? If an instrument like the GPS is warranted, do you deal direct with the supplier if a fault occurs, or do you have the delay of passing it through the boat builder, then his supplier, before reaching the repair source?
These are the basic questions you should be prepared to ask about every RIB on the market. There are others concerning whether the payload quoted in persons means a slip of a thing, or a 20 stone diver and his equipment. There is also the question of the delivery date and whether the builder will accept an entirely reasonable and binding financial penalty for lateness. There are certainly some agents who will take your deposit against a quoted date, then put you further down the queue if another order comes in from a pushy cash customer insisting on immediate delivery.

This piece has been written under separate section headings, but each major question also poses several minor queries, even before you ask about spray rails, hull configuration and whether the seat is a mere box, or slightly pyramidal so as not to bruise your legs.

The best advice is to make a written list of all the questions you want answered and to have it openly to hand when you discuss spending several thousand pounds of your hard-earned money. If the supplier does not wish to play your game of twenty questions, go find somebody who does.
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