Dominion 2-HW ,a Self-Righting Foiling RC Keelboat/ One-off Design & Build Project - Page 5 - RC Groups
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Oct 16, 2015, 03:13 PM
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FKS(Foiling RC Keelboat Scow)--Dominion IIRC


I got the lead in today-surprisingly quickly-ordered on Wednesday from California. As you see it ,it is .875"(7/8") diameter X 12" long X 2.95 lb. When finished it will be around 2lb. It arrived very well packaged and bent a little which does not matter. This looks to me like it is going to be a great way to create a bulb for a one-off boat. I started a thread here to try to get help: https://www.rcgroups.com/forums/show....php?t=2521512 And one of the guys made a suggestion about a tungsten rod and that got me thinking about trying to find cast lead rod/bars. I'm lucky to have found this company:
http://www.rotometals.com/product-p/...m?1=1&CartID=0



Last edited by DLord; Oct 16, 2015 at 03:21 PM.
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Oct 16, 2015, 08:03 PM
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FKS(Foiling RC Keelboat Scow)--Dominion IIRC/ Summary


BASIC DESIGN SUMMARY 10/16/15UPDATED 10/24/15
Most design work is complete with the design of the foil trunks being completed this weekend. I'm giving consideration to making the foils adjustable under sail-from max extention to max retraction which will be 2" either side of what you see in the working drawing of the shape below. The radio box is between the mast and the keel with servos,winches, receiver located there with the exception of the side to side Trapeze Power Ballast System winch which is built into the ballast system. If I make the foils adjustable by radio those servos(or servo) may be waterproof Hi Tec mounted on deck.

FOILS
The foils will be 17.375" span from the bottom of the hull to the tip with an 8- 9% t/c ratio. Chord will be constant at 2.1875"(2-3/16"). The section will probably be symmetrical for the first couple of inches(below the boat) transitioning to an asymmetrical section. Area of one side is 38 sq.in..(area of one side of nominally immersed foil=34sq.in.) One foil will be able to carry 80% of the load which at 8lb displacement is 6.4lb. Foil loading then will be .188lb/sq.in..of the immersed area shown in the sketch. Initial foil loading(both foils) before takeoff will be around half that.
Foils will not be retractable* but will be removable. The boat can be sailed in real light air(under 5mph) w/o them. Rake will be manually adjustable. There may be some twist to the foil over a portion of the span -maybe as much as 3 degrees-still working on that.
* They may be able to be moved up and down about 2" from the position shown in the working drawing below. This would allow me to experiment with flight altitude and raise the windward foil to give it more clearance when sailing on the lee foil.
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NOTE-foil area and loading updated 10/23/15.
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=============================================
SAILPLAN

See post 66 below for updated Sailplan.
Last edited by DLord; Oct 24, 2015 at 11:18 AM.
Oct 16, 2015, 08:45 PM
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Q23 fullsize


A new picture of the boat flying with spinnaker:

Oct 18, 2015, 09:33 AM
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FKS(Foiling RC Keelboat Scow)--Dominion IIRC


Adjustable foils: I'm working on a system that will allow the foils to be manually set to the position shown in the sketch or two inches deeper to test the effect of the increased altitude. At either setting the windward foil will be able to be retracted two inches to help keep it clear of the water.
The angle of incidence(rake) of the foils will be manually adjustable.
In order to make this work, the trunks will be somewhat special with sheet(.015" adhesive ready) teflon glued to the insides of the trunk and .25" teflon rods will be installed at the bottom of the trunk. At the top of the trunk a "slider" will be used with .25" teflon rods at the front and back. The trunk sides will be extended aft a bit to take a bolt used to adjust the AOI by moving the slider fore and aft and then retain it. A carbon tube will fit inside the forward trunk tube and extend up about three inches to support a block used to raise the board.
More on this as I go forward.
====
NOTE: as of 2/13/16 the foils will not be servo adjustable. I've found a way to eliminate that requirement. See page 13, post 194.

Picture of the full size boat with the windward foil retracted to the same degree that the model foil will retract:

Last edited by DLord; Feb 13, 2016 at 01:54 PM.
Oct 21, 2015, 10:45 AM
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FKS(Foiling RC Keelboat Scow)--Dominion IIRC


Finally received notice that my balsa has shipped from National Balsa* yesterday afternoon. The material for the foil trunks will be in late today.
Looks like the target weight of 7lbs was unrealistic and will probably be reset to 8lbs after a lot of work trying to get it accurate. Part of the increase is for two waterproof HiTec servos that will be used to adjust the main foils-each weighs about 2 oz. And the servo will use a push rod-not line-to move each main foil and will be able to do it when fully loaded.
At 8lbs, 4lbs is for movable ballast and keel ballast. The movable ballast can be removed if conditions warrant-so with that removed the target weight is 6lb all up.
New sailplan later today.........

* delivery Monday the 26th
Last edited by DLord; Oct 22, 2015 at 01:32 PM.
Oct 21, 2015, 02:46 PM
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FKS(Foiling RC Keelboat Scow)--Dominion IIRC


Here is the new Sailplan(next to the previous Sailplan) to go along with the higher target weight. Note that the boat has a "WingTip Rig" that I first developed in the mid 90's. It's main advantage is the rotating very small carbon gaff that gives the main an excellent planform and allows there to be an adjustable upper outhaul that works very well. The jib also uses a small squaretop. The jib boom is a Garry Hoyt invention that acts as a jib vang and allows the jib to be tacked down on the center-line as opposed to the end of a rotating boom as well as automatically increasing camber as the jib is eased.
While sail area was increased from SP 1 to SP 2, the height of the CE remained nearly the same. The fore and aft position of the geometric CE didn't change significantly,either.

Note: LOA changed to 52" 11/24/15-see post 105.


Last edited by DLord; Dec 01, 2015 at 04:59 PM.
Oct 24, 2015, 11:15 AM
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FKS(Foiling RC Keelboat Scow)--Dominion IIRC


A bit more detail with Sailplan 3:
1) Max heeling moment before depowering= about 12.76 ft.lb.
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2) Max wind before depowering= about 9.5mph(8.26 knots)
After depowering, with increased wind, the rig will be reefed or a "B" rig will be used.
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3) Maximum righting moment=12.85 ft.lb..This occurs with an 8lb boat weight and the Trapeze Power Ballast System fully extended to windward and the boat at a 9.5 degree angle of heel.

For reference:
a-about the same RM as a 6lb square Mini 40 trimaran,
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b-2.44+ times the RM of a Marblehead heeled 30 degrees with a 22" fin(from the boats CB) and a 7lb bulb.
Last edited by DLord; Oct 24, 2015 at 12:34 PM.
Oct 24, 2015, 04:51 PM
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FKS(Foiling RC Keelboat Scow)--Dominion IIRC


In anticipation of getting started Tuesday morning I got the building board laid out for the 10 1/8th inch bulkheads. I had to lengthen the board due to the 50" length. All the balsa and glue should arrive late Monday. Hope it's good stuff.
The board is ready for the bulkheads to be glued in place:

Oct 25, 2015, 06:21 PM
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FKS-RC / Dominion 2-HW


Well, the "type" that best describes this boat is: FKS(Foiling Keelboat Scow)-RC.
And I've come up with the final name of this particular boat:
Dominion 2-HW which is based on the name of the first and most classic tunnel hulled scow-and HW to honor the inspiration I've received from Hugh Welbourn who designed the Quant 23-the first foiling keelboat scow in the history of mankind-see earlier in the thread. I will use a foil system on this boat based on the foil system of the Quant 23 but tailored specifically for this boat.

Oct 25, 2015, 09:55 PM
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Tri foiling


Im sure you guys have seen this tri foiling you tube video.

Sorry if this is in wrong thread.

I was just amazed at how well he has it sailing. I have to imagine alot of experimentation to get it going like this..

On you tube type in - FAST HYDROFOILING SAILING WITH RC MULTIHULL

also the 2nd video same tri at champion lakes Australia. WOW..

Anyone know what design or details.
thanks
Last edited by fizzzy; Oct 25, 2015 at 10:10 PM.
Oct 25, 2015, 10:31 PM
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Quote:
Originally Posted by fizzzy
Im sure you guys have seen this tri foiling you tube video.

Sorry if this is in wrong thread.

I was just amazed at how well he has it sailing. I have to imagine alot of experimentation to get it going like this..

On you tube type in - FAST HYDROFOILING SAILING WITH RC MULTIHULL

also the 2nd video same tri at champion lakes Australia. WOW..

Anyone know what design or details.
thanks
=========================
Wrong thread but that's ok. I think you're talking about Ian Holts Mini 40 trimarans. He's done an excellent job of getting the trimarans foiling-and fast. The Mini 40 is 1.2m X 1.2m with .9sq.m SA and is relatively popular in Europe and Australia.
The FKS would never be as fast as Ians boats but it wouldn't capsize either.
Check out the German RC multihull forum here: http://www.rc-network.de/forum/forum...hp/166-Mini-40
lots of information about the Mini 40 cats and tri's as well as some about the 2m class.
Oct 26, 2015, 06:40 PM
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FKS(Foiling Keelboat Scow)---Dominion 2-HW


The balsa from National just arrived-but the package was short one of the tubes of glue I ordered. We'll see how they handle it tomorrow.
Oct 27, 2015, 10:19 AM
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FKS-RC / Dominion 2-HW


I'm happy to report that National Balsa handled my missing glue very well-they're sending another tube immediately. That makes my experience with them pretty good. The balsa looks real good. So next step is laying out the bulkheads and keels and cutting.
I have a Dremel 16" scroll saw so that should go fast.


Last edited by DLord; Oct 27, 2015 at 10:33 AM.
Oct 28, 2015, 05:46 PM
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FKS-RC / Dominion 2-HW


I'm considering rigging up a micro servo controlled gybing keel to help optimise windward ability.
And God willing and the creek don't rise I'll have the bulkheads up tomorrow and she will all of a sudden be three dimensional.....
Oct 28, 2015, 07:51 PM
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Fks -rc


Doug, cant wait to see your progress . Keep it coming.
Cheers Fizzzy.


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