Thread: Building the OZ PD Racer - now renamed the OzRacer

Michael,

I'm definitely going to use the lug but I've had further thoughts on leading the mainsheet to the daggerboard case. When I had the Pacer I was continually losing my hat overboard when the loop of sheet under the boom caught it when tacking. If I attach the sheet to the centre of the boom as Brian does on his scow, would a 3:1 purchase be enough for the little bloke (he'll be eight) to handle the sail? Would it be better to go to 4:1 (as long as I don't cleat it )? Also how would this effect sail shape, is it better if the sheet pulls on the end of the boom?

cheers,
clay

Howdy Clay,

If using centreboom sheeting the boom will need to be a fair bit stiffer. I would add about 9mm depth in the untapered part - the ends can still taper down to the same size.

I would be guessing that 4:1 will be necessary - maybe more.

The other way if you want to consider the 2:1 endboom sheeting with the run along the boom and the drop to the back of the centrecase ... is to do what most boats do to avoid critical hat loss.

They put a plastic loop or two or bit of the narrow seatbelt webbing that hang down like a U from the boom between the two blocks.

This supposedly prevents dehattings and beheadings. Personally I have never had a problem with either despite many years sailing NS14s and more than a few sails and races in Lasers.

MIK

Thanks Michael,

I think I'll stick with the endboom sheeting and try some loops to guide the sheet. It may not be such a problem with a smaller diameter sheet anyway. The sheet of the Pacer was about 1/2" so there was a fair weight of rope hanging down.

BTW the cheapest ratchet block in the Whitworths cattledog is an RWO #R5431 ($57.95 ). Do you know it and, if so, does it comply with the OZPDR Rules?

cheers,
clay

Mike,

I found more information on that RWO block and it does have a switch to change from ratchet to free. I can't find any that don't, any suggestions? Maybe I'll just have to use a plain block and reef if the sail gets too hard for the little bloke to hold.

Also by my calculations the downhaul you suggest for the Goat will give a MA of 6:1, outside the OZ rules. Will the same rule apply to downhauls as vangs i.e. 4:1.

I only ask because I have lots of relatives in Adelaide and seeing them will give a good excuse to drive over for an Aussie Campionship .

cheers,
clay

Howdy - Riley make a ratchet block that fits the rules. It is about the cheapest on the market ... about as ugly as you can imagine, but it will still be working in 2050.

Yes ... you will have to bring the Downhaul or vang down to the rule requirements if they are to be adjustable. If you just tie them off you can have 100:1 if you like!

MIK

Originally Posted by Boatmik

Howdy - Riley make a ratchet block that fits the rules. It is about the cheapest on the market ... about as ugly as you can imagine, but it will still be working in 2050.

Yes ... you will have to bring the Downhaul or vang down to the rule requirements if they are to be adjustable. If you just tie them off you can have 100:1 if you like!

MIK

Michael,

I just checked and the RRP of the Riley RM324 is $64.43 which is more than Whitworths' price for the RWO with a switch . I know the rule was designed to keep costs down but discount wars seem to have made it redundant.

I thought it would be good to have the downhaul easily adjustable on the water. Will the rules allow 4:1 for the downhaul or does it have to be 3:1 like other sail adjustments. BTW I think 100:1 is a bit over the top . Besides I'm not sure the rig and sail would be able to take the strain .

cheers,
clay

Howdy Clay,

Problem above a certain point that frictional losses become much greater than the mechanical advantage as some point ... so it is diminishing returns. I doubt that for a rope purchase with 1000:1 that it would be possible to move an item weighing a few grams and with a very great deal of effort.

I will announce something about the ratchet block in the News section of hte PDR website before any champs and grandfather that one in at least temporarily. If the price goes up then I will reinstate it much be an unswitched one.

Don't worry ... the main point is to have fun, so I will work out a good way.

Best wishes
MIK

Thanks Michael,

I'll test the 4:1 rule if/when I make it to a championship .

cheers,
clay

Oh ... but that would be terrible Clay!

Imagine ... you could win every event and then someone go .. 1, 2, 3, .... 4

Muuuuuuuuum .. HE IS DOING SOMETHING ILLEGAL.

m.

LOL I can just see the headlines in the yachting press:

"There was an uproar at the Puddle Duck Australian Championships today when the winner of the coveted Wooden Spoon was disqualified for a rule infringement. The furor continued when the second last place finisher refused the trophy on the grounds that he did not deserve it as he had at least finished every race."

OK looks like it's 3:1 or no cleat.

clay

Nice to see that PDRbuilding is kicking off again in other threads on this forum! Looking busy out there!

MIK

Forgive me if this is written obviously in the plans... I may have missed it.

I've got my lug rig spars all shaped. I recall recommendation to glass up to where the boom meets the mast on the sprit leg o mutton rig but my question is about where glass is needed on the lug rig? Do I glass up to the boom AND down to the yard? Any glass on the boom or yard where they meet the mast?

thx
Shawn
Charleston, SC

Not really needed in an absolute sense. a bit around the partner area is good though.

Problem is that the lug boom and yard will be set up slightly differently each time. Actually ... not a problem ... but that is the way it happens.

MIK

Howdy Shawn,
I had some confusion about 'glassing the mast' (p 49., second paragraph) too - there must be some words missing in my plan which made me be not so sure about how the mast should be glassed. Afterward I checked some related photo-streams and I saw that it is the area around the partner which needs to be glassed (and the ends of mast and boom with 50 mm glass tape of course).
At the moment the last layer of epoxy has just dried on my PDR's mast, centerboard and rudder ready - hull is next.
Bests
Csaba