Awesome fun

Absolutely bloody magic guys

thats insane!!!
What speed did you and Daff crank it to Matt??

what? No gybe!

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boardboy said...

what? No gybe!

I was thinking gybing would be an adventure...

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boardboy said...

what? No gybe!

and it needs to be a duck gybe...

So, did you get a decent speed?

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FormulaNova said...

boardboy said...

what? No gybe!

and it needs to be a duck gybe...

So, did you get a decent speed?

No.

In our defense, there was barely enough wind to get going and it took 3 or 4 tries as it was. Perhaps 16-17 knots and 5.8m Koncepts. I think we just touched 30 knots.
We were hoping to get a Heli shot of it but got it out just as the chopper went back for the Col to land and change sides. By the time they got back there was just not enough wind to even dream we could get it going.

nice one lads !!

I think we need a GPS Team Challange Tandem results section.
So that we can track results and stimulate others to make one.

It would be good to track improvement over the years

We can gybe and tack the Starboard Gemini, but I cannot imagine gybing the SpeedTandem, it is far too small/narrow for that...

Any chance of getting some specs/dimensions on the board for a one-design speed tandem challenge. I take it that it is a polyester/pu board with a us finbox...

No problem.
You will have to translate into metric, but basic measurements are 10'8" x 20"
I will make some more measurements on Thursday and post them.

It was made on a Polyurethane Burford blank which had its rocker reduced when the single stringer was inserted. I am not sure of Burford still have the moulds for this blank. I was disappointed to find they don't have the 'speed board' moulds any more.

The US fin box (Chinook) is a both an advantage and a disadvantage. The advantage is that the position can be adjusted fore and aft for directional trim, which we have found quite critical. The disadvantage is that we can't easily use the latest available speed fins which are all Tuttle base.

For our 'slalom' tandem we will be building an adjustable 'Tuttle' box so we can trim the fin fore and aft.

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Kimba said...

Any chance of getting some specs/dimensions on the board for a one-design speed tandem challenge. I take it that it is a polyester/pu board with a us finbox...

Hey Tim are you looking for a new project for the winter. I have a couple of old boards if you need mast tracks or power box fin boxs.

may want to set some ground rules if there is a challenge involved.
like only sail in your own state, Ha ha.


finally got internet back after 2 weeks bloody telstra.

hope to be speed sailing on sunday, friday looks good as well but robe wave comp is on.

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sailquik said...

No problem.
You will have to translate into metric, but basic measurements are 10'8" x 20"
I will make some more measurements on Thursday and post them.

It was made on a Polyurethane Burford blank which had its rocker reduced when the single stringer was inserted. I am not sure of Burford still have the moulds for this blank. I was disappointed to find they don't have the 'speed board' moulds any more.

The US fin box (Chinook) is a both an advantage and a disadvantage. The advantage is that the position can be adjusted fore and aft for directional trim, which we have found quite critical. The disadvantage is that we can't easily use the latest available speed fins which are all Tuttle base.

For our 'slalom' tandem we will be building an adjustable 'Tuttle' box so we can trim the fin fore and aft.

Thanks Andrew. I was thinking of doing a styrofoam board with d-cell stringers for more rigidity and a cheaper build as I imagine rigidity will be more important than weight. The adjustable Tuttle box is a good idea...are you going to do a trimbox type setup with bolt in blocks. It looks from the planshape like the rail has a lot to do with keeping it straight, where is the releasy point, under Mathews front foot? No problems with imperial or metric as I can enter either in my modeller...

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jimbob SA said...

Kimba said...

Any chance of getting some specs/dimensions on the board for a one-design speed tandem challenge. I take it that it is a polyester/pu board with a us finbox...

Hey Tim are you looking for a new project for the winter. I have a couple of old boards if you need mast tracks or power box fin boxs.

may want to set some ground rules if there is a challenge involved.
like only sail in your own state, Ha ha.


finally got internet back after 2 weeks bloody telstra.

hope to be speed sailing on sunday, friday looks good as well but robe wave comp is on.

Hi Jamie, thanks for the offer but I too have plenty of donor boards. I have an itch as I haven't made a board for 7 years... There are 2 in-line before this one though. I reckon they would be fun on Georgy Baby...

I had a few spare minutes and did a quick model by scaling your photos Andrew. The blank/block is 160L...

Great skills mate!

Looks very close to my eye. The tail is a bit rounder and perhaps a tiny bit wider and more parallel in the rails towards the tail, but very, very close. I will post some measurements tomorrow. Can you get measurements off your drawing?

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Kimba said...
Thanks Andrew. I was thinking of doing a styrofoam board with d-cell stringers for more rigidity and a cheaper build as I imagine rigidity will be more important than weight. The adjustable Tuttle box is a good idea...are you going to do a trimbox type setup with bolt in blocks. It looks from the planshape like the rail has a lot to do with keeping it straight, where is the releasy point, under Mathews front foot? No problems with imperial or metric as I can enter either in my modeller...

If you can do styrofoam with good stringers it would work. Full PVC foam sandwich would be pretty rigid too.
This tandem is pretty weighty which is one reason why it has lasted so long.
The idea with the adjustable Tuttle box is to make a long box with interchangeable blocks to fill the ends and wedge the fin in the desired position.

At speed the release point is at least at the back foot of the front rider! see my avatar.

If you work a long Tuttle box, think ,that you need always the ends of the box,
it hold the fin higher or deeper. Wolfgang

Correct Wolfgang. The ends will have standard Tuttle box taper shape and the blocks will fit between the fin and end to wedge the fin tight.

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sailquik said...

Great skills mate!

Looks very close to my eye. The tail is a bit rounder and perhaps a tiny bit wider and more parallel in the rails towards the tail, but very, very close. I will post some measurements tomorrow. Can you get measurements off your drawing?

Thanks Andrew,
The measurements from the model are...

Plan
Tail:283, Width:508(20"), Nose:280.
Length:3251(10'8"), Wide Point @200

Rocker
Flat:1800, 70@2800, Nose Lift:190
I think the flat would probably need to be shorter, around 1300?

Thickness
95@ rear sailor front strap
142 @ frontm sailor front strap
Max thickness 150 at front base.

Fittings
Straps(centres) 110, 415, 1100 & 1560
Rear base @ 950
Front base @ 2100
Fin trailing edge @ 270

Below are screen grabs not drawings so they are not that tidy...

I am amazed at how close Tims figures are. I finally took some careful measurements and will PM them to Tim to adjust the plans.

The actual length is 10' 6 1/2" which is spot on 320cm
The measured width is 20 1/4" which is 51.5cm

Widepoint is further back at 1850

The tail is a little wider as I thought: 50 = 159, 150 = 230, 300 = 289, 500 = 350

The measurements for the center of the footstraps are spot on but we have added and angled strap for the rear sailor using the front hole of the front strap.

Back mast track goes back to 1010mm from tail, and goes 230 forward in 2 steps.
The front riders back strap is also in the back track and goes forward the same amount for upwind sailing
Front track starts at 2140 from tail and goes forward 420mm.

The rocker is not as flat as it looks in the tail.
It is flat to around 90mm and then rolls over over about 100mm to another flat to 150. With the straight edge on the second flat there is 4mm of tail rocker. We used this type of rocker a lot on our smaller speed slalom boards and it works very well, allowing the board to ride on the tail flat but also plane up easy and ride flat in the chop. It certainly works on the Speed Tandem!

With the straight edge hard on the second rocker the total nose lift is only 150mm. Not sure how much if you held it hard on the back flat because my straight edge was not that long.