Building the OZ PD Racer - now renamed the OzRacer

[Boatmik]

Howdy Mark ... just looked through carefully and found a different mistake

I have double counted the chine logs so the entry showing
Gunwales, chines 19 x 19 2500 4
should be
Gunwales 19 x 19 2500 2

But your suspicions about the framing is unfounded ... I would let the current figure stand. ie
Framing for bhds and misc 19 x 19 17500 1

That's all most people need to know. But to explain

Bow transom framing 2400 excl bottom frame
Cockpit front bulkhead framing and side deck supports 4600
Transom excluding bottom frame 2800
Frame #1 1600
Frame #2 2200

This is 13600, but a bit extra to make sure all the long bits will come out of the supply I would up it by 10% so 15,000mm.

I think a lot of people will be happy to get the 17500 in the plan though ... just to cut the risk of a critical error. To have a bit extra up their sleeves.

I think that was my decision at the time. It looks like it would be possible to trim it down a bit ... but if a dud piece appears or some of the timber is split or something ...

MIK

[Theodor]

OK .. thanks for the quick recalulations. This is helpful. I also like having a little extra length to spare - I just wanted to check I wouldn't end up with 15m+ spare!

A few more clarification questions from the timber list while we're at it:
a. What are the stern/bow Bottom cleats?
b. What do the asterix (*) refer to on the list?
c. Is the cockpit front coaming 19x19 (p.38 in plan), 19x22 (p. 5 timber list), or 19x45 (p.38 on drawing)?
d. What is the centrecase rudderbox headlog?
e. Do you recommend carlins to be laminated with 19x10x2100 (4 off) or would it be fine to make them out of 19x19x2100 (2 off)? I think this is a what-are-the-design-considerations-in-doing-either-option type question.

Peter has been sourcing mills to find us some nice spruce for our PDRs so we should be ordering in the near future. We glued up the rudders the other day and Peter says they look great. Unfortunately our mate with the nice combination machine has given it to his brother to work on his house in the mountains. So our planer/thicknesser option has gone. We're trying to convince our wives of the investment potential of buying one for ourselves.

Thanks again for the clarification.

[Boatmik]

OK .. thanks for the quick recalulations. This is helpful. I also like having a little extra length to spare - I just wanted to check I wouldn't end up with 15m+ spare!

No worries ... do you and Mark think that you will document the building here at all. Might be nice to move things to a separate thread. I can do it ... I have the power.

A few more clarification questions from the timber list while we're at it:
a. What are the stern/bow Bottom cleats?

They are along the bottom edge of the bow transom and stern transom because the bottom meets at an obtuse angle. So they need to be a little deeper so they can be bonded to the ply with an overhang to have the extra angle.

b. What do the asterix (*) refer to on the list?

It means that the builder can use finger jointed timber for these pieces as it is cheaper in Australia

c. Is the cockpit front coaming 19x19 (p.38 in plan), 19x22 (p. 5 timber list), or 19x45 (p.38 on drawing)?

The designer is on drugs. Go for the timber list size ... I will get to cleaning that up ... we used wider stuff on our Mk1 boats but it is just to stop water splashing in. The 22mm looks best.

d. What is the centrecase rudderbox headlog?

The vertical piece that keeps the sides of the rudder case and the sides of the centrecase the right difference apart. It needs to keep the ply 25mm apart, then there is enough clearance for the 22mm centreboard and rudder blade to slide through.

e. Do you recommend carlins to be laminated with 19x10x2100 (4 off) or would it be fine to make them out of 19x19x2100 (2 off)? I think this is a what-are-the-design-considerations-in-doing-either-option type question.

On the boats I have done so far the 19 x 19 is JUST ok to take the bend. So that is where some of the spare timber might be useful? Or you could go to laminated.

Peter has been sourcing mills to find us some nice spruce for our PDRs so we should be ordering in the near future. We glued up the rudders the other day and Peter says they look great. Unfortunately our mate with the nice combination machine has given it to his brother to work on his house in the mountains. So our planer/thicknesser option has gone. We're trying to convince our wives of the investment potential of buying one for ourselves.

If you do try to get a second set of blades thrown into the deal.

MIK

[koala]

Dear Michael
As I was just about to cut the rudderbox sides I noticed that some PDracer like here http://www.flickr.com/photos/boatmik...7594524425079/ or look at post #139 on this thread;
they both have their sides upside down re. to your plans specifications (page 64).

The straight horizontal edge should be on the bottom, right? Then the tiller follows the angled top edge. Is that correct?
Pete

[Boatmik]

haha Koala .... that is ancient history now that pic...

I cut them out the right way and Midge built them upside down!!!!

But I forgave him about 10 posts later in that thread.

There are some significant differences in the building methods between those Mk1 boats where we were trying to find out way and the Mk 2 boats in the plan. The main place is the way the centreboard case and the frames that support it at either end go in.

Also the mast partner and step have been streamlined and I changed the depth of the hull slightly to allow some extra ply for the side tank faces - I had to use big epoxy fillets on the Mk1 boats.

Probably the photo series here will help.
http://www.flickr.com/photos/boatmik/collections/

Particularly the "Building the PDRacer" and a shorter version is "Dakotas PDR" - the things we can all learn from an 11 year old!

Michael

[dopeydriver]

Or should that be finishing !.
Finally , finally , we are moving to close to the coast , on a river , and I can hopefully finish my PDR , and get it on the water.
Hopefully , by summer , as we have a lot of other work to do..
Anyone in the Portland Vic.area ?.
Regards Rob Johnson

[Gyula]

Today was sailing day again
It was one of those rare windy days in our town so we went to sail on our local river.
The other boat is a D4.

[Boatmik]

I just get blown away by the lovely appearance of that lug sail.

(for those who don't know the design and construction are a supplementary part of the OZ PDR plans - the standard rig is the tall sprit rig you see in the other pics earlier on)
http://www.pdracer.info

It is a flat piece of polytarp with one curved edge against the yard that does the business in collaboration with the bend of the yard.

So the all up cost could be from about $25 to 50 depending on grade of polytarp etc.

The foot has some convex curve and the leach (back edge) has a bit of concavity to prevent fluttering. But this simple sail is as good as many professionally made lug sails.

I thought it would take some adjustment to get it right!

But sometimes designers are lucky!

Best wishes
Michael Storer

[koala]

Dear Michael

I'm close to building the hollow mast for the PDR. I have 4m long spruce boards (5 pieces of 95mm wide and 4m long). Obviously I need to make at least one scarf joint on all four sides of the mast (wide and narrow staves).
The question is should I make these joints high up the mast or low down on the mast?

Should I alternate them from side to side (one up on down on narrow staves and the same on wide staves)?
Thanks,
Peter

[Boatmik]

yes ... having them up and down is good Peter!

Michael

[arbordg]

Peter - The theory is: you want to stagger the scarfs as much as possible. Worst case would be to have them all lined up at the same mast height. In practice, you do the best you can to seperate the joints.


"In theory, there is no difference between theory and practice; in practice, there is" -- Chuck Reid

[Gyula]

My friend made a short film

[ame="http://www.youtube.com/watch?v=-pljlVGhaW4"]YouTube - More sailing on Mures river[/ame]

[b.o.a.t.]

WOW!!!
That little boat fairly hoots along !!
Hard to believe it's an 8' x 4' box !!!
Well done Michael & Gyula !

AJ

[Boatmik]

I couldn't stop laughing ... that is a CRAZY speed for the little boxy boat!!!

Thankyou Gyula!!!

Michael

[Gyula]

I never sailed an other boat (except my model boats) and there are no other boats here with same sail surface for comparison so I don't know if it is fast or not but I love it
There are two D4 boats, but their sails are much smaller.