I’m starting on the main hull internals and I have a few questions.
It looks like the plans call for Futaba S5801 sailwinch. I’ve always used RMG but the RMG will not fit as well. Is the Futaba the winch of choice for this tri?
What thickness should I make the keel foil? Since there is not any weight on the botton I was thinking it should be thin as possible? Should the foil be covered in glass cloth?
The plans show the mast step going all the way to the bottom of the boat hull and hinging on a horizontal pin and a mast ram located at deck level. Is this common? It sure would be easier if I could just mount the mast on deck . 1/2" dia tapered carbon tube the mast choice? Any links to purchase from?
What is the common sail construction for a fast sailing tri? I was thinking of making mylar paneled sail like my IOM sails, but the sails would need to be much flatter. Is paneling necessary and if so, what is the amount of camber built into trimarn sails. It has to be less than a mono hull sail right?
Here are some pics from starting the main hull internals. I made the fin and keel box. They are both made out 1/8" lite ply with 2 layers of .7 oz glass. I will glass the complete fin box after it is glued together. Also attached will be the starting pieces of the rudder. I will make the rudder out of three pieces of 1/8 Lite ply and the horizontal foil out of 1 piece.
Hope to start on the mast box today.
I also have one float hull glassed and both arms glassed. The arms seem amazingly strong.
The sail servo is back ordered so I can build the servo mount yet.
I’m not sure if this transfers over to the model boat world, but all the full sized multis I’ve ever owned used foil shaped rotating masts stepped on the deck with bolt rope equipped multi panelled full batten mains. A round mast is the most unaerodynamic shape you can get. Since you’re in Texas you might try Ludwig rc yachts as a source for a mast extrusion.
I have got some more completed on my Trimaran this weekend. I primed and painted the float hulls. I am a little disappointed on the fiberglass finish but it will be OK. It gives me a great appreciation for the pros out there who can make a perfect hull.
I also started installing the main hull internals. See pictures following. Installed is the mast box which I made wide enough to fit a 1/2" dia. mast. The pin is a 5/32 brass rod taken from a piece of the rudder post. I did email Larry L and he will supply the 2m long aluminum masts. I’m not sure how to rig a rotating mast with the pin at the bottom?
The keel box is installed. Also installed is the sail winch mount and carbon fiber tube to hold the bow turning block. I found a way to fit my spare RMG winch but will require cutting the hull to get it out if the need arises. The winch is set at angle to align with the bow turning block.
The rudder construction is completed. The rudder is fairly thick so it shouldn’t stall if the rudder is put hard over. One change I did here is mount the rudder post vertically. The drawings indicate the rudder post at a right angle from the bottom of the hull, however, this would change the foil incidence when the rudder is turned. Will coat the ruddder assembly with epoxy.
I still have to mount the rudder post tube and rudder servo. Install the radio pot.
See the attached pics of the internals. Also attached are a couple pics of the port side of the main hull showing the foam removed ready to accept the stbd hull with internals.
You may notice the mast box and keel box extend past the hull on the top and bottom. This will get trimmed flush once the two hulls are glued together.
Mahoo
WOW!! I am glad to see that someone is also building a 48" tri. I just started and am sanding and sanding and sanding on the plugs. Hope to hit the gel coat stage next week. Do you know of anybody else who is building a '48 tri"??? and how is yours coming along???
Hearing about Mitch’s build has interested me in building an RC trimaran. I have actually started building. I also live in the Austin, TX area and am a member of the same model sailing club as Mitch.
I am using the same ghost train plans as Mitch. In fact my hull was cut on his forms.
SO it is official, the race is on to see who will have the first central Texas F48…
Hi Julian,
I and a few other US owner/builders are very pleased to hear of this possible renewed interest. Perhaps you are right, and it is time to start promoting the multihull “idea/concept” again.
It won’t be a huge class as you do realize we multihull folk are outcasts in most monohull dominated clubs - but what the heck - just having the ability to share ideas would certainly be helpful.
This weekend, I’ll see if my old forum site is still up or accessible, and all of you are welcome to share and participate if/when you wish.
Do to some challenging “persons” who frequent many forums doing self-promotion under a variety of names, it may be a requirement for a “real name” - even if a screen name is allowed. But let me first see if the old site can be reactivated.
Just as a matter of information, I am suggesting the following classes for discussion, and perhaps one new one that might draw some interest, mainly because of much smaller size.
For discussion and consideration, I am thinking:
2 Meter
F-48/Mini40
1 Meter/MultiONE
and for those who may have size concerns, I plan to try a boat at the RG-65 size of 65 cm/26-1/2 inches to see how well a small multi will sail.
I know big boats sail more realistic than tiny ones, but if there is any measure of performance in a small multihull, I’d like to take a closer look. There may be trade-offs necessary at the smaller sizes, but fun on the water by many is the ultimate goal.
Chad (forum administrator here) has been most helpful in supporting us “weirdo’s” so it may be helpful to move all the old forum stuff here - giving it a dust-off to bring it more up-to-date.
Will post once I get a chance to look “backwards” at what might still be out there.
Yes, we have two Ghost trains being built now using the glass on foam method. Having another one on the way has motivated me to finish mine. I just need to complete some finishing touches on the main hull internals then glue the two halves together and glass. In case you all haven’t see it, there is also a great construction thread on RC universe building a Nightmare using the plank on frame method.
I did a bit of digging and found the old F-48 multihulls discussion forum is still up and accessible - but boy, is a lot of the posted info kind of dated!
We could use it again, but I would hate for new folks to the site to accept posted info from back in 2004-2005 (many don’t look at posting dates) and also some of the posters aren’t around to defend their views. An item of interest is that we didn’t have Mike Dann’s email address back then, and much info came via Mike Howell (no deceased). Today, MIke has been a bit active and has even posted here once or twice as I recall.
Perhaps it would be better if I lobby Chad to provide a few sub-topics under the general heading on this forum - and bring some of the more pertinent items/info forward. Another problem is trying to remember my password to access it as Administrator - but I’ll keep looking. In the meantime - here is the link and I’m asking for comments from the multihull interested crowd as to which way to go.
:rolleyes: