keel trunk and rudder mounted…
trial fit of the deck. hull still needs a final trim to the sheer line and I need to figure out my internal electronics. I don’t think I’ll have any space issues… pretty sure the rudder servo will be surface mount in the cockpit. and a dual arm sail winch, single purchase…
Looking very good Marc! The lower part of the deck looks very low to me… won’t water flow inside from the back?
Tarm…
you are correct, the deck is too low aft. the gap between the bottom of the cockpit and the hull should be a bit bigger. my plan is to put in a small foam spacer to account for the sag. the bottom of the cockpit should be level with the chines on the hull and the deck pitch from center to the sheer line should be greater than what is shown in the pic.
the deck is so wide and flat that it wants to sag.
I will have similar issues in the bow area of the deck which will be exacerbated by the fore-stay mount on the deck wanting to raise the foredeck like a tent… once I put tension on the rig
here is a line drawing of the real boat…
Marc - take a look at Claudio’s idea on attaching a jib rack to the bottom of the hull and having wires lead to deck. I think it was in his Marblehead free plans if I’m not mistaken.
Dick,
yeah I have seen that. dave creed has a novel solution for his IOMs and one that is pretty simple. a few peices of glass formed into L shapes… the idea being you epoxy the bottom on in place first. mount the deck, and then glue in place the upper as it passes between the two lowers. and abit of epoxy… serves the same purpose.
I hadn’t seen that one. Thanks for the post
here is a pic of one I made last night…
not as nice and refined as the one dave creed makes…but should do the job nicely…
it sails… turns lightning quick… but when pressed, it really seems to want to push the water like a barge…
also some video…
http://youtu.be/mj-0VKUOAHE
http://youtu.be/we1R04khfCQ
http://youtu.be/uRWtR4-3Rgw
hopefully will have a practice day soon to try it against other rgs…
RTS weight is 1420 grams…
Marc, it looks fantastic! (and you built it really fast!)
Yes, looks like it turns on a hairpin. Please keep tell us how it goes against others…
Hey Marc - just a thought. Try sailing it with main only. It may have too much weather helm, but I am wondering if the bow will stay up if not being pushed down by the jib? Obviously giving up some sail area, but if it works, you can always make up an oversize main - staying with the regulation mast height, but extending the length of main boom for larger foot size. Just try it by removing jib and tying off forestay.
Tarm,
I think that fact that it doesn’t have a pointy bow is what makes it turn so quickly… the bow skims over the water as it turns…
My keel weighs 640 grams…
I figure the 1420 is not a bad weight, since I’ve basically used enough fabric and epoxy to build two hulls…and I’ve never built any hulls that are light…
Nice videos. You can see in the videos that the scow without the typical chin that digs in
rotates around the keel better. I think it might be a real good light to medium air boat.
Mike
Hello my friend,
I hadn’t seen the new project of yours.
I do not know if you have seen it but I am building a mini Transat in a scale of 1/7. (92.5cm)
Now that I am used in the shape of it (width) everything else looks like arrows.
I haven’t finish it yet and I do not know the way it sails but from the videos that you have posted,
I saw that the boat accelerates when it is heeling.
I understand that it is because of the gust but I have reasons to believe
that you should have a lighter ballast so as to help the boat to heel more.
This way I believe you are going to have much better performance upwind.
YehaI saw and commented in a few places on your 1/7 transat
it will be interesting to see how it compares to other conventional hulls
Dick,
not sure how I mised your post about removing the jib… I guess in a pinch I could make a “una rig” But then I’d have to drill a hole int he deck and drop in a tube ect… and make it a free standing rig…
problem with a main only would be a really bad weather helm…
We’ll see how it does on sunday against other boats… I think putting some heavy batts in the rear on either side and reducing the bulb weight or lossing the keel bulb altogether would also work… to help keep the nose up so it “skims” over the water rather than pushing it out of the way…
Blunt entrance was already known in the Fifties and this was used in order to create a divergent bow wave as such to reduce the hull contact surface with water in the first meters with hollow wave formation and therefore aiming to a reduction of friction. It din’t last long !
Personnally I can immagine that a very wide bow may suffer of a loss of pointing capability unless compensated by larger fin area and where the skipper can manage to control the situation… Still curious about Marc future developments and comparative tests anyhow !
It is never too late to learn !!
Cheers
ClaudioD
This added sketch would explain better my toughts
OK Marc - it is Sunday … we’ll be watching for a post. Hope it went well for you.
Dick
well sail against 4 RGs, one sympatico “glass hull” and two simitara (breaking winds styrene hulls)
it was light flukey less than 5 with the occasional puff when the boat powers up the bow goes down and it begins to act alot like a barge. so rather than skimming across the water i’m just pushing it out of the way, which is very slow.
so…I need to get weight aft . servo’s and a 2 cell lipo are already aft.
thoughts… add ballast on the aft corners and reduce ballast in the keel. Since the hull is so wide, having the ballast in the corners would result in the same righting moment or keep things as they are and add a T foil to the rudder to help trim the bow up…
It seems to point ok once it gets moving… but with no bow knuckle it is “twitchy” feels like it handles like a go-cart… made more than a couple mark rounding and ended up nearly hitting the mark as a result of the tight turning radius…
out of seven races I finished dead last in all but 2. took a second and a third. but it wasn’t because of a fast boat…just took advantage of others misfourtunes…