I remember reading somewhere that if the main hull of one of these designs is used with the floats of the other, the result is a better boat.
Can anyone tell me if this is true, and if so which is the best combo.
Thanks
OK. Which is the better boat in general then. I have plans for both, and I am trying to decide which to build. There will be at least 3 of us building so we want to get the right one.
Freight Train has a very wide and broad cross hull selection from waterline down (tear drop shape) which would seem to be a lot of surface area (drag). It also has only one (wing) for cross beam.
Ghost Train has two cross beams, and is at least one generation of design newer than the Freight Train design - if I recall correctly. Both are by (UK) Andy Mcculloch and there have been a number of hulls built to each set of plans. I like teh asthetics of Ghost Train, and also like that Andy included a rig plan with various sail area dimensions.
Some have built the Ghost Train hul and the SnapDragon floats - just to muddy the water a bit more. For you New Zealand guys - if you build to the Ghost Train lines, I think you may find a few more come out of the woodwork and you may find yourself with a fleet of them - email Alan Hayes at Kiwi RadioYachting as he has one and may be enticed to revive his interest if there are going to be others built there.
Or you could give your fleet a real quick start and buy my boat! (Any reasonable offer considered)
Mine is a Ghost Train, my old boat (Short Sharp Shock) is in Auckland, it is a Ghost main hull with Freight floats.
In my opinion the true Ghost sails a lot better and easier but I couldn’t say whether it is only the floats or whether the lower weight of the new boat and some other mods I made were the difference
Been following the trimaran threads and now seriously thinking about building one too. Perhaps the ghost train since the plans are available. I have a couple quick questions:
- If the Ghost requires additional bouyancy forward, would extending the forward lenghts of the hulls be worth while? Would this move the center of lateral resistace enough to change the rig plan?
- What would the weight difference be between a built up hulls (laser cut frames and planked with 1/8" balsa )and a quick build hulls with foam and glass? Would the additional weight be a benefit?
- Fabricate the curved arms with carbon cloth and balsa core in a shaped press to define the shape?
- Any other tri plans out there to consider that would be considered current? Seen the freight, nightmare, box, etc.
Thanks All, this could be fun.
Mitch
Hi Mitch -
here’s my opinion …
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As I recall without unrolling my plan sheets, I think the GHOST TRAIN floats are already at maximum length. Staggering them slightly forward of main hull would help reduce pitchpole, but then overall length would exceed 1.2 meters (48 inches). It might be better to just lengthen the shadow templates to add a bit more height to the bows, or slightly more curve to the shadow templates to add a bit fuller bow buoyancy. Alternatively - as Alan did on his - is to add some small foils to the floats to force them up when the go into a wave. They are small and only stick out horizontally maybe 1/2 inch or so. Kind of like the small rails on a full size Shearwater cat of days gone by.
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If you leave the foam inside of a skin of glass, you might add a pound or two at most. If you cover the foam with plastic tape, layup two layers of 4 oz. glass cloth you will have hollow hulls with are much lighter and only need bulkheads where cross beams attach. Balsa strip covered in glass probably falls in the middle somewhere as far as weight. Obviously instead of glass cloth, you could skin with carbon which would help with weight - whether you left foam in place or removed it.
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Many will cut a ply core to gull-wing shape, add foam to each side and fair to eye and then cover with cloth. Those anxious to get on the water will simply purchase carbon tubes and go with straight round cross beams. I think part of the multihull appeal is to make it look like a real tri with the gull-wing cross beams - but it does add extra work. On my first F-48, I laminated up a series of very thin cedar strips to form the curved beams. A bit heavier than carbon and foam, but they retain the desired “wood” look which I personally enjoy. They are finished “clear” so the various wood color of laminations show.
A French site by Jean Margail has drawing for WATER RESIST which has hulls that resemble the old “Phillips” catamaran with the wave-piercing bows. You can also get the plans free by emailing him. (He also has plans for a 2 Meter sized cat!) See photos below - my hulls with curved wooden beams - a completed Water Resist F-48/Mini40 - and line drawings of the boat in general for reference.
Good luck with the prospective build. ADDED: PS - where are you located?
Thanks for the quick reply,
I think I did run across the water resist plans as well. Any plan best suited for a tri newbe to get around in tacks?
I did see a later tri from Andy called the express train (based on a Mongoose??) and the floats shape looked like it was at max depth at the bow. Would this added depth give the added bouyancy up forward as well? Thats one advantage to the foam. I can add volume pretty easily.
I’ll have to build it with the gull wing arms. That is what makes the boat in my opinion.
I’m located outiside of Austin texas and currently sail a Vic, Star45 and Disco IOM.
Mitch
Sorry - but I’m not familiar with “Express Train” lines.
Yes - foam is easy to modify and a pretty fast build, although some guys are really quick laying down balsa strips.
Would love to see a tri down that way. Kris Harig was instrumental in setting up the 1 Meter trimarans, and he was in Tulsa as I recall. He kind of dropped out of sight, and not sure if he stops in to read forum or not.
Try the 1/8 or 1/4 inch plywood to cut out the general gull-wing form shape (viewed from bow) and then add foam in front and in back to shape. Once you get what you like, you can add glass and mounting connections at each end of the beams.
I’m pretty sure the ‘Express’ pre dates the ‘Freight’ which in turn pre dates the ‘Ghost’.
Important to get the trains lined up right
How are the arms connected to the floats? With the gull wing arms turned down at the floats, it looks like the arm penetrates the hull into socket tubes? How is the arm connected to the main hull?
Noticed the fiberglass on foam construction method. This might be the best of both worlds. Are the foam pieces in half and is there an small overlap section to glass together? Or do the FG pieces butt up and then connect the halves with FG tape? Seems like butting them together would be tough to line up perfectly.
Thanks everybody, looks like I have a new fall/winter project.
Mitch
When time permits, I will post some construction drawings I happened to find an a site in Brazil. Local lady of latin backgound did a little translation, but said it was Portugese so some pages aren’t translated since she wasn’t sure. Not being a sailor didn’t help her with translation either.
By the way - I ran across the photo of my glue-up process for the cedar cross-beams that were laminated. 4 inch PVC pipe cut into narrow slices, and then cut through in one location makes for excellent, easy to make and inexpensive clamps. The general shape was cut from 3/4 inch chip-board, slightly undersize to allow for some springback. They slide into glass slots in each float and are held in place by machine bolt into a 'T" nut. They are thru-bolted into aluminum backing plate on main hull. Plate is embedded into main hull and glassed in place.
That will be great if I can get a tri building guide. Even if it is in Portuguese.
I do like the idea of the floats having sockets and detaching from the arms as needed.
Here is a series of detail photos which are from the Brazil site. Most are self-explanatory
This photo shows a float that has been shaped from foam - suspended between two nails so it can be rotated and the glass cloth applied.
These photos - Thanks to Alan Hayes of New Zealand - show the cross beam attachments during construction phase. Another photo shows the small foil/rail along the hull designed to help prevent pitchpole. The third photo shows Alan’s boat powering along and showing speed.
Again, my personal thanks to Alan for having shared these (and many more) way back when I was first starting to build my multihulls. Without his kind assistance and support, A lot of trial and error would have taken place.
Here are a couple more ideas of how a cross beam “could” be connected. The all white boat is French, but I don’t recall where I got the other - or to whom it belongs. Just more from my “photo vault”. 
In the second photo, the builder elected to use what appears to be common aluminum electrical tubing and tube mounts. hey work fine, but aren’t pleasing to my eye. Then again - as speed and 100 feet away sailing in a pond, do looks count - or is it strictly functionality?
Thanks for the contruction pics. I am now considering building foam 1/2 plugs and FG the plugs and then joining the two FG halves together as per your earlier photo. Any photos how you joined the two halves would be appreciated.
I noticed on one of the pics that the dagger boards were installed in the floats, and not the main hull. The dagger boards are at a angle inward. I have also noticed this on some full sized multihulls as well as a foil that curves inward. That kind of goes against common thinking that foil should be vertical in the water to provided maximum lateral resistance. Would this be worth while on a Ghost Train hull?
Thanks again Dick for all your info,
Mitch
Mitch -
A vertical board is to provide lateral resistance and to help the “lift to windward”. In Alan’s case, there is some vertical to prevent side slipping, but they may also be angled inward slightly. Consider the boat heeled to one side. The lower portion of the foil may be parallel to water surface. If it is angled with leading edge up just “slightly” it could be trying to lift the float and thus prevent a pitchpole.
I never asked Alan if he had any incline angle when heeled on those foils - or if/how well they worked. Perhaps he would be so kind as to offer his experiences.
As for joining, I cut a strip of foam about 1/4 inch thick by about 1 inch wide. I attached it inside one half of the hull, allowing for a 1/2 inch extended “lip”. When first side cured, I used the extended “lip” to align the other side of the hull. It provided a way to hold both halves together and then I used masking tape along various spots to hold everything in place until the second side cured. After hulls were glued, I ran two strips of very light fiberglass cloth (some .75 oz. stuff) along the seam where the two sides came together. First layer was 2 inches wide, the second layer was only 3/4 inch wide which allows the seam to be faired and blended to the hull sides.
My apologies but I never took photos of that. I can sketch if you don’t understand the description. Let me know.
I’ll have to think about the lift of the foil. It’s in the middle of the hull and probably wouldn’t give much lift on the bow. They do look cool though. I will post this question on a boat design web site and see what the experts say for the reason for the inward angled foils. The one advantage I can see fin in the floats is it will sit up right on the fins and rudder.
OK, I understand your hull construction method for joining the two halves. Does the foam go around the entire hull joint?
I was thinking of fabricating my hulls with a overlapping joint. Each hull will extend 1/2" past C/L. I guess a small offset will be required so the inner piece will slide into the outer piece. This will give double the thickness of FG where it is needed most.
The foils I out on are angled, I forget what the angle was:)
The foils are also asymetrical and so provide lateral and vertical lift, one day while out sailing in a strong breeze (>20kts) the whole boat was briefly lifted out of the water in a gust.