Wing Design Concepts

The moth has been and should continue to be a development class so the natural next progression is towards a better aero package.

It's probably no surprise to learn that we have been designing a wing sail for a moth...as we suspect a lot of other mothies have been doing. They've been around for a while on C-class cats and seem to work well. Below are a couple of notes for developing a wing rig for a moth:

Requirements

• Weight - tricky one, extra weight can be acceptable if the boat is faster around the course. consult VPP
  
• Watertightness - gotta be able to right it after a capsize
  
• Survivability - not essential but handy. if repairability is high not as important
  
• Repairability - if it breaks, must be easy to repair in a boat park
• Better Performance - waste of time otherwise, although it would be cool, consult VPP and mojo
  
• Transportability - not all of us can afford to pay ppl to look after our boat 24/7. break down to either component parts or easy to fit in a regular trailer. 2x2 piece option may work
• Cool - can't look too shabby
• Cost - preliminary costings indicate that unless it is a full carbon monolith, the cost shouldn't be too extreme compared with a traditional rig (mast, stays, sail and development of these). mods to the hull are another matter, particularly if the requirement is to switch back to conventional configuration quickly and easily.
• Arrangement - A stay-less wing rig seems like the best option on a moth. On shore handling and durability of the rig are the primary concerns with stays. This isn't locked in stone though.
• Construction - Good if it can be homebuilt without special requirements (space, tools, etc).
  

Our revisions so far

1. full composite - likely to be too heavy and expensive
   
2. composite and heat shrink - not a bad solution in terms of weight and cost, used by C-Class et al ie proven construction, transport is a killer
   
3. sock over frames - with spinnaker clothe, light, cheap, not likely to be water tight and durability concerns
   
4. styrofoam modules - cheap, heavy, don't capsize on a petrol slick, UV issues, water absorption issues.
5. composite and heat shrink modules - demountable for better transport, a bit heavy, easy(ish) to build
   
6. composite and heat shrink nested modules - easily transportable, not too heavy, but stiffness might be an issue without careful designt. Nesting refers to the open bottom which slips over the module below when rigged. All modules nest together like a russian doll for transport.
7. composite and model foam nested modules - easily transportable, not too heavy, easily repairable, cheap enough, better stiffness than with heat shrink, free flooding but also free draining.
   

Option 5 (frames top and bottom)


Option 6 (note open bottom, glass leading and trailing edges shown)

The spar would just be a square carbon beam, nothing fancy and easy for a home builder with experience.

Note that we haven't even gone into performance and shape requirements yet, it is believed construction is the biggest hurdle to overcome.

Will it be feasible? Can we be bothered to build one along with the hull and beam modifications?

You'll just have to wait and see...or do it yourself...

QLD States

QLD moth states over 17-18 April.
Probably the first regatta where the foilers leaked more than the scows.
Fleet was 3x M2, 1x BR RX, 1x BR x8, 1x Assassin, 1x Home built foiler, 1x LR HT, 5ish scows.

More photos here, some are good.



I got back from a trip to china on the 17th, was hoping to make it out on the 18th but was struck down with teh ills, so i caught a ride on a rescue boat instead.

Perfect weather, nice easy 13kts or so when i was there on teh sunday. Appartently the saturday was much windier with some short chop.



Final foiler results:
1. Brent Pearson
2. Sandy Cavill
3. Steve Sherring




Final results for scows:
1. Mick Kohler
2. Pete Williamson
3. Mike Willcocks



Just one skiff, Nick Taylor.



In other news Nick has found an underloved BR RX and is giving it some loving till its sold. w00t! training partner.

nsw states

great place to sail.



my boat didn't go upwind, just reached back and forth.
don't know how to fix it yet - should be obvious with more practise.



some advice from other people were:
- improve foil finish
- bin the foils and buy new ones
- don't use 40mm cams on 50mm
- wand too far offset from CL
- use more vang



a repair of the push rod rebroke during the 5th race with 3 to go. Nick and I managed to jury rig a tension system and so the boat was back on the water for the final day.



boat at the rock? i thought it was bigger.

Sucker for a Pretty Face

Bladerider RX used less than 10 times.
Excellent condition.
$15,000 asking price
Located in Brisbane

Anna.Patterson ( a t )
goodman.com

Stress Less Refit

While Markla is well underway with boat handling and getting up to speed in his boat, I still don't have a boat of my own. I've been umming and aarring about the viable options; buy second-hand or rebuild an old boat with second-hand gear (already have access to a very narrow shell lying around). Ultimately I would love to buy a new boat and not worry about getting sticky fingers, but I just can't see the value in them for a relative newbie.

Decisions, decisions...

The bare hull shell that was stress less is sitting at Markla's parents place gathering dust and snakes. As part of determining whether it is feasible to rebuild it, I present an early rendering. Current thinking is to move towards socketed beams rather than what's shown. Maybe something similar to whisper but without the freestanding rig, a stump stepped mast perhaps. The stress less hull is very narrow but relatively light so I see no reason it can't be converted to a foiler. It will need some carbon reinforcing from mast to cb case though. The biggest problem is finding a place to do the refit.


Foils are also an issue. Markla has been investigating the design for a home-built set and we've got heaps of ideas for building them relatively easily. More on that later though.

Lots to think about...