SLINO Builds

Could the anonymous coward :) who commented here last month that they were doing a group build of 3 SLINO's please send us more details.

http://perverted-moth.blogspot.com.au/2013/05/queensland-state-titles-yeppoon.html?showComment=1367742927114#c8483886250895736746

I want to know details and see progress photos.

PB Speed Records

Not much in the grand scheme of things, but today Markla, Rob and myself went out at Lake Samsonvale just north of Brisbane for some big wind and flat water.

Markla and I set new pb speed records. (Below is for our archives as much as anything.)

10 seconds
Markla - 22.3 knots
Narkla - 23.6 knots
Rob - 22.1 knots

5 seconds
Markla - 23.2 knots
Narkla - 23.95 knots (because Markla won't let me round up to 24.0)

200 metre
Markla - 21.7 knots
Narkla -22.9 knots

Peak
Markla - 24.9 knots
Narkla - 25.6 knots
Rob - 22.8 knots (speedpcuk) (but he wasn't trying, pfft, boat retired hurt before the wind really kicked in)

nationals 2011/12 in photos

some of me have been trawled up from the depths of teh interwebz.

i think i'll find a real guy fawkes for next wongi. 

count teh convolutions

bow is to the right in all renders.

the pushrod input is the pair of rod ends in olive colour on the right hand side. the pushrod is not perpendicular to the centreline, hence the rod ends. 

this goes into the first rocker (pinkish). it has the same ratio and phase as the wand lever so the rotation of the bolt at the bow is exactly telegraphed (not sure if this is important, but may help with future development). 

phase can be adjusted on this rocker by spinning (nigga) the on board bolt,  draging the right hand side of the green linkage around that arc track. this is set up for adjustment on the land only. i may add a nob (ur) to the top to make it adjustable from the cockpit. 

green linkage is a turnbuckle that is needed to use the extreme range of the phase adjustment. for minor adjustments to phase, it shouldn't be required, the brown rocker just won't stand up straight. 

brown rocker is the gearing. spinning the bolt drags the input pin up it's track. going up amplifies the signal. it has a rope guide on one side only that moves with the rocker, however i expect it will be able to be adjusted from both sides of the boat, it will just need to remain rather tight, and i may need to make some sort of lead for it. 

next is a blue linkage made from a turnbuckle. this acts as a dial. just before it exits the machine there are two nuts on either side of a plate. these are limit screws that mean no matter what you do upstream, it will bottom out on this plate before damaging the centreboard pushrod. will also be a convenient way to see what the flap is doing. 

bearings are to be pressed in, then retained with worm screws. i have just bought some shock aborbers to add into there somewhere (probably on the pink one, with a screw to adjust lever to for dampening). wand length, bungie and wand stopper will also be run to the tramp, seperate to this machine but equally complicated. 

all plate parts are watercut 4mm aluminium hard coat anodized. bolted to the boat with 5x M5 countersunk fasteners into a carbon channel bonded to the deck. 

resistance prediction, table of hydrostatics

resistance numbers and table of hydrostatics now available as part of the design package.

i don't really have much to say about them except they may be useful for anyone doing a VPP where the lowriding, or partially supported case is of interest.

SLINO Weight Estimate (with pie!)

here i am, friday night watching 7:30 queensland on ABC doing a weight estimate for a boat i have already built and weighed. 

well, its one of the remaining files i promised with the design package. and maybe i am feeling a bit compulsive. 

but it does show some interesting things. the centre of gravity is futher aft and lower than i would have expected as shown in the graphic below (note it excludes skipper weight)

the weight calcs result in the following numbers:
     hull, paint, gantry   = 11.87 kg
     wings (alloy), tramps  = 9.89 kg
     foils, tiller  = 8.50 kg
     rigging, standing, running, control, mast, sail   = 13.06kg

    Total = 43.33 kg
 
This distribution is illustrated below.

this is clearly 6 or so kg overweight. as I have noted previously, changing the wings to carbon would save around 3 kg. changing to dacron tramps (rather than trampoline material) would save some too. and I need to change to carbon spreaders. 

the remainder i think would need to come out of the hull. my construction method of laminating the seams of prefab panels results in a lot more bonding than a moulded boat (2kg i would estimate). 

how else to save weight? maybe less hull, particulary in the foredeck. or if you were confident in your boat handling maybe a lighter panel laminate, like nomex and prepreg. 

that rigging component is still a large piece of the pie. easy to see how a wing is viable from a weight point of view. 

updated design files

Some recent interest in the design has inspired me to complete the design package for the boat.

Lots of detail info here:

http://perverted-moth.blogspot.com/2010/11/slino-design-files.html

New drawings are:

SL2-E1-02__04A - Hull Construction Details
SL2-E2-01__02A -  Centreboard Construction Drawing
SL2-E3-01 Stem and Transom Lug Construction Details
SL2-E4-01 Wing Mounts Construction Details

SL2-F4-01A - Running Rigging Arrangement

SL2-G1-01A - Control System Arrangement
SL2-G1-02A - Control System Parts

I am hosting them on google docs. if anyone has trouble downloading them could you let me know and i will investigate different hosting arrangements.

UFO? / Virtual Punter

n4rks sent this to try to prove to me he has a boat. and it flys. 

i think it is a rather sketchy photo, like those ones of nessie (teh monster, not teh wife), and ufos and stuff. therefore should be subject to doubt. i am even facing the otherway. and winning for that matter. well jack and steve are sort of in front but that's not the point. 

while not sailing nor working and bored i decided to try maknig a version of virtual spectator in rhino script to prove i can do anything in that program. i think it is the best and at 1k worth every penny. i am rather pleased with the results. rendering of the video needs some improvement but it has a lot of potential, and once i have 2D nailed 3D rendered graphics should be simple. background images were systematically raped from google maps at 5 different zoom levels to make up a matrix of around 20,000 tiles. but that is a different story. 

now i just need some decent GPS tracks. 

housekeeping

a couple of pictures i have been sitting on from the worlds, first courtesy of Thierry and the second from Ben Rankine.

UPDATE: 

Karl, 

I purchased a 2 piece mail foil off a friend at the worlds and spent most evenings adapting it to suit the boat. Only got it ready for the final day of racing. On the way to the start line, after 20 seconds of foiling it failed thru the socket, pushrod tearing open the TE of the vertical. 

Once the lifter had departed, the rapid descent must have overloaded the bottom leg of the gantry, it bucking under compression. I have a Dave Lister style articulating gantry which saved the rest of the gantry, but it rotated up and snapped the tiller off on the hull. 

I was able to recover the lifter vertical, gantry and rudder were still attached, but the tiller/worm drive/extension goned. 

Windward Heel

Could've sworn I posted this ages ago.

I was wondering why 15 degrees seemed to be about the right windward heel for best performance upwind. Also wondered how much lift was actually required by the foil at such a heel angle and the transverse force balance of a moth at such a heel angle. Was fairly convinced this was all related so I developed a spreadsheet to find the heel angle that balances the vertical and transverse forces determined from the righting moments.



If anyone wants a copy to play with, let me know and I'll email it to you.

Good photo of Mark from Worlds

Foredeck

Just mucking around with some concept designs...





More of the hull, deck and wings to come. Not happy with them as a whole yet.

Luka's Lister Boom

For anyone interested in the merits or otherwise of Luka's boom I present the following. Be warned, it was done in about 10 mins while I was having lunch at work so it is a bit simplified...

150kg vertical leech load
100 diameter thin wall steel boom
10mm round bar steel vang
20ish mm round bar "spreader"
2.5m boom
400mm gooseneck to vang take-off

Conventional Boom

Bending Moment


Deflection = 14.5mm


Luka Boom Arrangement


Bending Moment


Deflection = 13.2mm

A little over a tonne of tension in the vang in the conventional arrangement and a little under a tonne for the Luka setup.

Is it worth the complexity?

nick in teh boat

SLINO Design Files

Please Note:
I am publishing this information as a personal reference only. If you chose to replicate it, it is at your own risk. This information carries no warranty and has not been thoroughly thought through or engineered. Building and sailing a moth to this design could seriously hurt you and/or cost you a lot of money and/or cause emotional damage.

If you do attempt to replicate derivate from this information please send me an email – I am always interested to see where this design leads. (mr.markla@gmail.com)


See Also:
http://perverted-moth.blogspot.com/2009/01/new-moth-design.html


Documents and Calculations
SL2-A1-01A - Drawing and Document List
SL2-A1-02A - SLINO Build Sequence
SL2-A1-03 - Parts List
SL2-B1-01 - Weight Estimate
SL2-B2-01 - Table of Hydrostatics
SL2-B2-02 - Resistance Prediction


Drawings
SL2-C1-01 Side Profile Drawing
SL2-C1-02A - General Arrangement

SL2-D1-01A - Hull Lines Drawing

SL2-E1-01A - Hull Construction Drawing
SL2-E1-02__04A - Hull Construction Details
SL2-E2-01__02A -  Centreboard Construction Drawing
SL2-E3-01 Stem and Transom Lug Construction Details
SL2-E4-01 Wing Mounts Construction Details

SL2-F1-01A - Wing Assembly
SL2-F2-01A - Gantry Construction Drawing
SL2-F3-01A - Spreader Construction Drawing
SL2-F4-01A - Running Rigging Arrangement
SL2-F5-01__02A - Cradle Arrangement

SL2-G1-01A - Control System Arrangement
SL2-G1-02A - Control System Parts

SL2-H1-01A - Hull Jig Assembly
SL2-H1-02A - Deck Jig Assembly
SL2-H1-03A - Foredeck Jig Modification

SL2-I1-01A - Carbon Cut File (1)
SL2-I1-02A - Carbon Cut File (2)
SL2-I2-01A - MDF Cut File (1)
SL2-I2-02A - MDF Cut File (2)
SL2-I3-01A - Hull Panel Marking
SL2-I3-02A - Deck Panel Marking


Rhino Models
All models have the same zero point, so you can import (or worksession) the components into a single file.
SL2-R1-01A - Hull Construction
SL2-R1-02A - Hull Jig
SL2-R1-03A - Wings

SL2-R2-01A - Centreboard

SL2-R3-01A - Rudder

SL2-R4-01A - Control System

SL2-R5-01A - Wing Sail

SL2-R9-01A - Cradle

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.

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.

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)

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.

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...