Pimp my ride
I’m slowly getting through the list of mods to make to my Bladerider. Slowly.
This weeks addition… PBO shrouds.
I’ve been trialling a prototype forestay for the last couple of weeks, and it’s worked well. So now it’s all go on producing a full set. Dog is ramping up production and provided they work well, i’ll bring a bunch of them with me to Garda.
Why do it? It’s going to save close to half a kilo in the rig. Not that much in absolute terms, but then the rig doesn’t weigh much either.
Then there’s the stretch. 2.5mm standard wire elongates to about 12mm at half breaking strain (200kgs), but the new PBO will stretch about 2mm for the same strain.
It’ll be interesting to see if I can notice the difference that makes to the boat. It’ll also be interesting to see what will give when the boat nosedives and the rig loads up.
Anyway, if anyone wants a set, give me a yell and I’ll see what I can do.
April 23rd, 2007 at 12:18 pm
Scott,
Your mechanics is about what we would expect from a compueter engineer.
Stretch or elongation is mm. OK (1 mark)
Strain is a unitless measurement of elongation divided by length or in your moth stays 12mm/4000mm = .003 for wire, or 2mm/4000mm = .0005 for PBO. (0 marks)
Load should be in Neutons because anything in KG is a mass. I think you mean load is 200kg x 9.8m/s/s = 2000N near enough, or 2kN (0 marks)
Stress is load / cross section area. For your 2.5mm dia. stays area is 0.0000049 sq M. Stress is 2kn/0.0000049 or about 400 MPascals which sounds more like the breaking stress of the wire or PBO rather than the safe working load. (0marks if the mast falls down)
1/4 FAIL
What about the windage?
April 23rd, 2007 at 1:28 pm
Thanks Phil. Very edumacational.
April 24th, 2007 at 1:59 am
Hello Scott,
could not find an email link on your site so posting instead. If you are inetrested in selling your bladerider after the worlds at garda then please let me know.
Regards Christos
April 25th, 2007 at 7:11 pm
Hi Scott,
if you haven’t done it, it could be interesting to have a chat with Jonno from the 12 ft. skiffs. His boat is on PBO for a couple of seasons.
Cheers from Germany
Philipp