Sunday, August 29, 2010

4 – Accident With Local Consequences / steve mothing

there was an unnatural amount of dust gathering on boat, and we finally had wind for the first time in months so we tried to take the boat out today. water was the coldest i have ever felt the gold coast.


session finished 20mins later after I chernobylled another gantry and push rod.



nick took a short vid of steve sailing:


Click me for more photos of Steve.

Monday, August 9, 2010

spreader construction booring.


while the world is ablaze with wing rigs, I just did a booring sketch woot to answer the question below.

Hi Mark,
...The cut file you provided included spreaders, but judging from your email you haven’t converted these into a finished product previously? My plan is to tip the spreaders with glass to stop the wear from the stays, and to add uni down the sides to cover the core and to give it some more strength. The Bladerider spreaders have a protrusion on the spreaders that fits into the fitting on the mast that you sent a photo of. I’ll search in the Ronstan catalogue for something similar to the fitting that John Illet uses on his spreaders, but in the absence of a ready made solution, I’ll just cast something in glass....

Yeah, I had every intention of making myself carbon spreaders, but I had an alloy set lying about and I have been using them ever since.
The cabon cut file for the spreaders is still sitting in the garage and may get finished some day.

Attached is a drawing about how I was going to do it.
The key is:
  • Remove the core from the tips of the spreaders.
  • Lay up some solid fiberglass (not carbon - glass is harder wearing, alternating passes of double bias or woven roving is ideal) plate to 5mm thick
  • Cut the fiberglass plate to shapes that will fit inside the decored area.
  • Glue the fibreglass plate in and then lay some 200 uni carbon (UD-C) over the top of the cut part over the length of the spreader arms.
  • The spreader base can be made the same way, cut an E glass part that is approx 60x20, with a radius and a pin hole where it will attach to the mast.
  • The UD-C should lap over the top of the protruding part of the E Glass plate.
  • Ronstan part is RF917 with the pulley drilled out

I haven't tested this laminate yet, but seeing how light on the prowler spreaders are I think it should work. As soon as the UD-C has cured you should have a good idea if it is strong enough.

Cheers

Mark.

Friday, July 30, 2010

Ski Trip Bazinga!

The gang are off for a ski trip to NZ, specifically Mt Ruapehu, starting this weekend!

Markla and Nessie should be taxiing now with the rest of us stragglers coming in waves tomorrow.

Wish us luck and no broken bones...

wings

i did up a drawing of the wings on my boat for reference to the new slino. this drawing is available thru my google docs (i will gradually transfer all of my drawings to this site - still not sure where to put the rhino model and cad files, for now these can be emailed on request).

at the moment I am running aluminium wings as noted on the drawing. i also did some calcs for equivilent carbon wings (based on CST products):

76x1.27 Aluminium (EI 14.37kN/m2)
*ID63x1.8 Carbon

50x1.6 Aluminium (EI 4.92kN/m2)
*ID35x2.5 Carbon
ID40.4x2 Carbon
ID44.7x1.8 Carbon
ID47.2x1.5 Carbon

40x1.6 Aluminium (EI 2.46kN/m2)
ID32x1.5 Carbon
*ID30x12.6x1.5 Ellipse Carbon

As drawn in aluminium the wings would be approx 7.47kg
Using the alternative carbon sections marked with * above gets 4.72kg

A bugetary price for aluminium tubes is $266, for carbon $1873 (again using the * sections)

Wednesday, July 28, 2010

new slino

i can't remember when but I sold the jig-mould-thing to a guy in melbourne and gave him some cut files so he could build a boat like mine. i just got some photos of his progress and they are attached.


gotta love the stealthy look.





more details as they become available.