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Paddy as of right now I have it set at 18mm as this was the minimum that Andy suggested. I will go down a if bit it runs a wet.
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Chuck that esc looks bigger than the CC 240 I ran in mine. Is the rear sponson boom still across the tub? These hulls do blow over if the weight is not right and those packs should get as far forward as possible. If your weight is not right you will find that you will have to run the strut as deep as 1" to stop the blow overs and this makes the sponsons run wet. I tried to aim to have the CoB as close as poss to the rear of the ride pads, not 2" back as the usual hydro formula would suggest. With the CoB approx 5-10mm behind ride pad I could run 18mm strut well into the 60mph range with only the occasional lift and it was controlable.
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NOT a shot at Andy.
This is a very contentious issue with me at the moment.
A common "rule" that is trotted out is 1-2" behind the sponson for hydros and riggers.
1"on a 18 "rigger is a lot different to 1"on a 32"rigger.
I have read that 10-14% of the afterplane is a good start area too. This make a little more sense than a fixed dimension.
FFS these hulls are quite different when you take into account Shovel nose, Pickle fork, Ventilated just for Hydros then come the Riggers with bare booms or even winglets like the X2.
One formula for all ??? Like F#$@ !!
A start point for all. YES !!
It is easy to set the CoB just aft of the sponson and start your trimming from there.
As an example.
Paddy has his CoB 24% aft of the sponson on the X3
Slim has his over 20% on the same hull.
Neither have blown over yet Paddy at least has gone over 110 Km/h
Set your AoA of your sponsons to the suggested point.
I am not familiar with that hull............yet.
Just listen to Andy or Paddy for strut depth measurements and this will give you an AoA that is measurable.
Run it and let us know.
If you are feeling brave then move the CoB aft untill you blow it over.
This CoB measuremenrt must be recorded and should be published, here with video.
VIDEO IS A MUST if you choose to go this way.
I will help where I can with tech knowledge.
Andy and Paddy have first hand knowledge of this hull so will provide a LOT of good information that will help you get this boat screaming.See it....find the photos.....sketch it it....build it........with woodComment
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Good comments Simon as this boat WILL blow over if you put the weight too far back. To stop mine blowing over I stole 3 of my sons fishing sinkers and they are right up in the nose.
Andy solved the problem a better way IMO.
See the pictures below and you will notice he used pieces of soft drink bottle on the winglets. When he told me about it and sent me the pics I was thinking this is some of Andy's
but now I own the boat I can see it works very well and his old boat is quite a lot lighter than mine.
Several boats in various stages of destructionComment
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Simon that is the formula I was refering to. The xs2 does not run well at speed to that formula. Because of the wings and the obvious lift they generate you will find that at 60mph you NEED the CoB at or close to the back of the ride pad,Comment
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First off thanks for the COB advice I will see about shifting things around to move it forward. Second I looked at the carbon rod going through the tub and it is not supported where the wings meet the tub. Is it glassed in somehow, supported by wood then glassed, or are the wings filled with 2 part foam for support? I don't want to cut it out until I have a plan or better understanding of how it is supported at this point.IMPBA 20481S D-12Comment
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Chuck the pictures below might help.
This is Andy's old boat. We both did similar things except I used thicker wood than Andy. You must drill the wood, remove the boom so you can let the boom slide through the drill holes and when you have the boom in place glue the wood to the hull. After it has dried for some time cut the boom and you open up the hole for the battery to slide almost all the way to the nose.
I hope that helps.Several boats in various stages of destructionComment
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Thanks Paddy that answers a lot of questions. Hopefully I can free up the carbon rod for this method - if not I may have to resort to drilling the hole and splitting the wood for a 2 part installation.IMPBA 20481S D-12Comment
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This is what I came up with. The aluminum was to thick to bend and a get good fit. So I looked through my lumber yard from when I built 1/12 scale doll houses and furniture quite a few years ago and found just what I needed. The pieces are glued with CA and ready to be epoxied into place.Last edited by egneg; 04-11-2009, 07:00 PM.IMPBA 20481S D-12Comment
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Even a little bit of glass ribbon just to make sure it is strong, and yes a cleaner job than mine. In my defence I was learning the art of model building at the time and now it would be a muck cleaner job.
When they are glassed in it will look like it came from the factory.
Excellent work ChuckComment
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A great thread. I have to build one and show you a**holes how it is done....using pieces of soft drink bottles on the winglets, give me a break! Now, a Scotsman would use, used condoms...no need for velcro...open the used condom and apply. A simple solution you Colonial twits
Paddy, I do like the new avatar, Andy's is land locked as is the egg man
Douggie the ?Comment
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Douggie you are just jealous because you only get to run boats once a year and that's if summer falls on a weekend! So you have 363 days a year for building boats.
BTW there is this wee pond ten minutes east of my house that never freezes!!!
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