1/4 tonners + the cup

As I understand it, one of the differences with IRC is that the formula used is NOT public, and that it also also revised quite often. Part of the idea is that whilst designers can make good guesses as to what will rate "better" (ie essentially create a boat faster than those on the same calculated rating) they should not be able to know for sure. I think it also essentially gives bonuses to features which improve seaworthiness and onboard comfort?

IOR and IRC are measurement based handicap schemes.

IOR was used extensively until the mid 80s but the current scheme used around the world is IRC.

IOR basically allowed you to calculate a length in ft which was then used to correct the boats elapsed time. From this several open classes formed ie, 1/4, 1/2 and 1 tonners. Basically these boats dont actually weigh 1/4, 1/2 or 1 ton but end up with an IOR length which is less than a given value for that class. From memory 1/4 ton IOR length was around 19ft by the mid 80s.

Unfortunately IOR created some strange designs, with hulls having large bumps to reach girth measurements and relying on lots of movable ballast, ie crew, to keep them going. The boats when measured had very low ballast ratio. Also the measurement was performed with the boat upright so large overhangs were used to gain waterline length when heeled. In the aftermath of the notorious Fastnet race, the IOR rule was heavily criticised for creating un-seaworthy boats, and some small mods to the rule were made during the 80s to try and sort this but the rule had already moved into decline.

IRC is the current measurement system in use, and I have to say I dont know exactly how the calcs are performed but it does seem to favour boats of a certain length. Ballast ratios seem high as do sail areas but I believe there has always been a 'fudge' factor applied by the ratings office which has often been the subject of much contriversy.

Anyway the re-born 1/4 ton cup is being run under IRC so many 1/4 tonners have been optimised with increased ballast (ie bulbed keels), fractional rigs with non overlapping headsails and larger spinnakers (area taken from the overlapping jibs).

The joy with any measurement based rule is that you can always optimise your boat to suit it, but it costs!!

Edited by craiggo

Okay for some one who is not massivly experianced in yachting but is intrested in and the idea of the 1/4 tonners can some one give me an idiots guide to IRC/IOR what they are how they work etc

You've completely missed the point! We bought our bolero almost by accident, we were looking for a sonata and while searching we came across the bolero.  The bolero was never designed to be competetive under 1/4 ton rating which is where boats like Purple Haze came from, she was an optimised bolero, smaller than standard with more sail and slightly different lines aft, not really a bolero as most seem to believe! That is beside the point though, our bolero was what was known as a Mk2, the difference being she has a lead keel, a small sugar scoop, an inboard engine and a slightly taller rig with jumpers and swept back spreaders (the standard bolero had a 3/4 swept back rig and an outboard with an iron keel).

Since buying the boat we have taken the inboard out becuase on a small boat IRC doesnt favour it. We replaced the old rudder with a new modern design because the old one was rotten and very very heavy! We have cut the scoop off the back to reduce overlaps now that the boat floats higher with 200kg of engine parts removed!

That was the end of our work on the boat until last years cowes week when we T-Boned runaway bus as they broached into us. We had some damage to the bow so while we got that fixed we also moved the forestay out to the bow from its previous position about a foot back. This gave us some extra fore triangle so we had enough room to make the genoa slightly smaller, turn it into a jib and sheet it inside the shrouds.  Doing this we went from 150% overlap to 115% which IRC also like.  We lost 2m of sail area from this which we added to our spinnaker and this allowed us a slightly longer pole for more projection because the SPL is a function of spinnaker area. Roughly 0.456 times the squareroot of the area.

For the price of some new sails and some patching up holes where engines used to go on top of the new rudder we have ended up with a much better boat to sail with much more room down below which is also faster around the windward leeward courses that we race on.  Fast enough to trouble the £50k boats at the top of the fleet at the quarter ton cup this year and finish in 9th overall. 

My advice if buying a 1/4 tonner is to either buy a really sorted one which should set you back no more than £20-25k and do nothing to it apart from buy new sails and sail the boat fast. Secondly you could buy a knackered old boat, the bigger ones tend to be more popular but just look for clean lines. Stick it in a shed, sand it back and strip everything out by hand.  All this should only have cost £7-8k.  Then spend the remaining 15k on a rig and a new rudder and some new paint.

Don't do what we did and buy a boat that someone had lovingly restored for cruising and then buy new sails for the old rig and then not have enough money for a new paint job and a new rig a year or so down the line!  You really have to take the time to get the boat right first time in the shed and then you can fiddle with it to make it faster.

As I have said though, most importantly look for a boat with clean lines, some of the boats had strange creases etc to make them fit the rule, perhaps these days the production boats that just happened to fit are a better bet because the lines may be cleaner.  Just a thought!

This past weekend i was sailing a quarter tonner in my local yacht club
regatta, built by my dad in 1986, with original everything, even sails!
Unfortunately it was only ever raced of the club PY and never got an IOR
certificate so we cannot race in the cup even though it is an original and
more with the spirit of the rules than these moderised ones!