High Performance MPX Foil/Self-righting Trimaran-The Test Model

hmm I just find a discussion of a build by Jim Cadwella who is doing his own vacuum infused molding of his foils. Doug did you also do vacuum infused molding of the foils for this project? is that why you are sending us there to compare the results?

 

BB, Doug did not send PM40 there, I did in response to his question about Cat's.

 

MPX Test Model-Mast Rotation with Noggle

Other than the cosmetics(finish of carbonated of noggle rail straps) I pointed out in post 898 the noggle/gooseneck system has turned out to be outstanding! The noggle controls rotation of the mast relative to the boom and does so automatically. The system can be easily modified to any greater or lesser angle of the mast/boom relationship. The MPX Test Model version works very well-I'm impressed. I want to thank Eric Sponberg for introducing me to the concept!
click for best view-

 

Ah my bad... I misread that. Ok. How's your project going? The site doesn't seem to have updates since late last year and you were making what looked like really speedy progress

 

-9 F doesn't allow Infusion molding or anything for that matter. LOL

 

Ah yes. A friend of mine just moved from Novi to Minot ND. And his video of him trying to get his dog to go outside to "do her business" is hilarious

 

MPX Test Model

Lets try to keep this thread on topic which is the MPX Test Model and the comparisons of the technical data from other RC foilers. Thanks.

 

Well Doug thought we were. We were looking at respective build times.

Question for you. You have said that this is your number one focus. But recently you posted that you had paid someone to build you a pair of carbon foils for a full sized boat that you have not even started on. Do you think the expense of that might have slowed down this project?

 

Foiler info

Curtis, Jim, Ian(?)PM40m-can you guys come up with an accurate wetted surface of your hulls plus foils before take off,please. That will allow me to get a pre-takeoff SA/ws ratio.
In a day or two I'll post a details of your boats and the F3 and MPX Test Model for ease of comparison.
Hopefully, this stuff will help us all as these boats get sailing time as well as helping other RC foiler designers to know when they're in the ballpark.
Thanks for your help.

 

Isn't your "noggle" basically a camber inducer? What advantages does it have over the conventional self tacking rotating mast system?

Why, when you've done everything else in carbon (including I understand, the radio control box) do you have so much stainless steel in the gooseneck area?

Why did you fit the mast rotation pivot at the front of the mast?

Just curious, based only on the photos above

and yes, PM40M is Ian

Richard Woods

 

MPX Test Model

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1) I'm not sure about the camber inducer bit-I have a box full of them and I don't see the resemblance but maybe there is to some extent except the noggle simply regulates the boom angle to the mast centerline not specifically the sail camber through a batten.
2) seems a lot simpler.
3) After Eric explained the noggle to me I was looking thru the Annapolis Performance Sailing catalog and accidently saw a fitting that seemed like it could combine a gooseneck with the noggle in a compact little device, so I ordered it and when it came in it was perfect. Virtually no work just assembling the boom and the noggle plates and it was done-and works perfectly. The "rail" to which the noggle/gooseneck and vang is mounted is carbonated to the mast with three straps.
4) Seemed like a good place for it to assure that the mast responds well. Many rigs like this have full battens that seem to aid mast rotation --this main has no full battens. The potential exists to use an upper full length diagonal batten but that has been removed from the pocket -at least initially-since I'm using a gaff.* Why?
5) Thanks-I'd seen the name on one of the great video's and thought it was probably his.
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*I produced quite a number of rc boats back in the 90's and early 2000's almost all of which used a version of a gaff in lieu of full battens. The "Wing Tip Rig" allowed a more or less rectangular planform and an upper outhaul and was a very effective main. Full battens(that I've seen) don't work well on models in light air and don't allow the control the upper outhaul on the gaff provides over the camber in the upper third of the sail. On the MPX Test Model, in addition to the gaff with upper outhaul, a "Gaff Control Device"(explained earlier) will be tested. Another advantage of the gaff is that it can serve as a convenient mount for an upper endplate and/or masthead buoyancy as in the Flyer cubed below:
Old video of some of the boats below:
http://www.youtube.com/watch?v=BRJDrWSZE6o&feature=youtu.be

Pictures,L to R-1) Worlds first production RC sailing foiler-F3 with curved, peaked up rotating gaff with upper outhaul, 2) Flyer Cubed 2m trimaran with gaff, upper outhaul and masthead buoyancy,3) Two Flyer cubed ,4) Micro Moth, experimental 36" monohull foiler with Power Ballast System,curved, peaked up rotating gaff with upper outhaul, 5) Left,"America One" with gaff, upper outhaul and vertical fabric endplate,Right, Spinnaker 50 with same gaff system as F3 and Micro Moth. These two boats were the first two RC spinnaker boats ever produced-sold about 25, 6) aeroSKIFF model with gaff and upper outhaul on the main and jib, 7-9) Super Scow 36 with Power Ballast System and same gaff system as "America One", 10) MPX Test Model main:
click-

 

doug
Full battens inhibit mast rotation. What they do is

• control sail shape across a wide range of wind speeds (which is why your lack of them is a surprising design decision)
• improve the entry shape on the leeside (assuming either a mast track or a sleeved sail

and all that SS adds weight - sure its simpler, but as Richard suggests, its anomalous to build the rc box out of carbon and use carbon masts and then load them up with oversized SS fttings

 

But surely you cannot adjust the rotation angle relative to the boom? And isn't it heaver than a piece of string?

As I say, just going from the photo, and with only mild curiosity

Richard Woods

 

MPX Test Model

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If the thing was to be produced it would be easily adjustable. It is adjustable in this configuration but requires a small amount of work.
What is the problem you see with the pivot point of the mast ?

 

I didn't say/imply there was a problem. I just wondered why you did it

If you fit the pivot at the front of the mast you increase the rotating mast lever, so it turns easier. But most masts rock backwards, so its probably better structurally to have it at the back. So that maybe is why most people compromise on the middle

again, just curious

Richard Woods