All things Class40
- Thread starter furler49
- Start date
I thought they were manufactured in Romania?
The way someone explained the difference in the manufacturing process to me compared to, say, your Selden product, is that Axxon lays the fibres by hand rather than using automated mandrel filament winding. The former process allows the fibres to run along the zero axis (i.e. vertical), whereas machine-wound fibres will always be off-axis to some degree. This means you end up with a heavier spar for the same stiffness.
Selden (Farr X2):
Greyhound37
Super Anarchist
Very exciting week for me. My newly acquired #39 gets launched this Friday after a stage two refit. I will spend the weekend getting her commissioned then we go sailing Monday and Tuesday of next week. First time sailing the boat for me, can't wait.
38°59'N
Member
38°59'N
Member
Many newer boats have gone to the single-spreader Axxon masts with a lower CG than the previous two-spreader mast. While those 1 spreader masts don't have a material weight difference, the increase in righting moment allows weight to come out of the keel.
Flying Solo
New member
- 29
- 2
Thanks for the feedback on the masts.
Congratulations Greyhound! Plenty of fun ahead.
Congratulations Greyhound! Plenty of fun ahead.
adamadamadam
New member
This is awesome, thanks so much for the reply. Cool to see how you were able to use large foam sheets over the male mould like that - often you see strip planked foam running for/aft in this build style - super labour intensive with a lot of fairing required - or female mould done in two halves... But you've managed large swathes of sheet foam... Neat.
Thanks, adamadamadam.
Yeah, the gripe against male molds is that they ultimately require a lot of fairing, but I think the process matters. The care with which you shape the foam is a big part, and since we did multiple layers of ply vacuuming, we could sand away small errors at every layer, which made for much less fairing in the end. We recently finished fairing the outer hull, and when all was said and done, we found that all the fairing for the entire 72m2 of the hull required a total of around 2kg of material. Not bad for a vessel of 4580kg. Again, labor intensive, but an encouraging outcome. (Kudos to our lead builder, Raoul!)
I thought they were manufactured in Romania?
The way someone explained the difference in the manufacturing process to me compared to, say, your Selden product, is that Axxon lays the fibres by hand rather than using automated mandrel filament winding. The former process allows the fibres to run along the zero axis (i.e. vertical), whereas machine-wound fibres will always be off-axis to some degree. This means you end up with a heavier spar for the same stiffness.
Selden (Farr X2):
All the main Class 40 manufacturers I talked to say they run at least 70% of fibers along the 0 degree axis, like Snowden says, and they all use pre-impregnated carbon fiber. Also, in my experience, all the "bare tube" weight specs of the Class 40 masts are within 1 or 2kg of each other -- pretty similar dimensions. (Incidentally, in reference to the original post, Axxon claims to be the mast supplier for 90% of Class 40s competing today!)
For the interested, here's an old but concise video that shows the basics of manufacturing that are still de rigueur -- including things like a rotating mandrel, vacuum-bagging and an autoclave.
adamadamadam
New member
Can I ask what your layup schedule is, and what foam (Corecell?) & thickness you ended up using?
bushsailor
Anarchist
bushsailor
Anarchist
To answer a previous question the boat we are modifying is a Ker 40. It will have around 1400 l water ballast and a coach house for weather protection.
Baptismal name :
yemenja
Plan :
Lift V2
Architect :
Mr. Lombard Yacht Design
Worksite :
Lalou Multi Composite
Year of first launch:
2021
Main Skipper:
Keni PIPEROL DAMPIED
Owner :
. Lalou Multi
Sure.
Generally, we used 25mm, 80kg closed-cell cross-linked foam on the hull and sides and 20mm on the deck. We used three plies of 400g biaxial E-glass for both the outer and inner skins, alternating axes 45 degrees per ply. We've kept a very strict 55%-45% fiber to epoxy ratio. We got good advice from one well-known Class 40 builder, and can say this schedule is not unusual.
For our part, we put an extra ply in the crash zone of the hull because, well, because we were told multiple stories of delaminations and soft spots there -- C40s can be bumpy. And like I mentioned, we used a combination of hand-wetting and placement with vacuum curing for each successive ply -- to ensure we nailed the ratios and had no bubbles or dry spots anywhere.
Compared to most other Class 40s, I'd say our stringers, floors, and bulkheads or smaller in dimension but more numerous -- e.g., we included some diagonals among the longitudinal and traverses. So, they're lam schedule is not that different from the inner hull schedule. Foam formers and three or four plies depending. To stiffen the hull even further and spread distribution of the massive keel loads of the boat, we integrated an additional composite floor grid at midship to which we will attach synthetic cables from the foil. We'll laminate this grid with S-glass instead of E-glass.
One small thing is that we're integrating composite chainplates for shrouds and stays. They're built with unidirectional fiber running in the direction of the load, and as a matter of construction these fibers get 'woven' into the hull at the points of reinforcement, so that sort of becomes part of the lamination at those points.
We've made samples of laminated panels and tested them with hydraulics to make sure our laminations were what we thought they were. We've been really pleased with all our results so far.
P.S. Really love the slow-hardening epoxy from U.S. Composites. Great for our (very) warm-weather build. Excellent outcomes.
That's kind of fascinating. A Ker 40 for far offshore double-handing. Would love to see how you install the water ballast tanks and systems in that boat!
Something that might interest only me: I can't help but notice how far inboard he has his backstays attached. I believe I've always seen the runners attach at the very corners of the transom -- presumably because the wider spacing reduces their effective loads via geometry. Not to say that his set-up was the reason the stay busted, but... interesting.
