| Trailer question #157824 10/21/08 11:22 AM 10/21/08 11:22 AM |
Joined: Jul 2007 Posts: 976 France pepin OP
old hand
|
OP
old hand
Joined: Jul 2007
Posts: 976 France | I have two cats and two trailers right now, and I want to swap the trailers as the one which came with my Nacra is more recent and lighter to move around. In order to do so I have to install new hull cradles on the cross bars and so on. But I was looking at the A class trailers on the parking lot at Grafham this week-end and they do not use hull cradles at all, they use beam supports (because I assume the hulls of an A class are too thin and light to be strapped down on cradles). Somewhat similar to the system on this roof rack. Anybody tried such a system on a F16 trailer? pro? cons? | | | Re: Trailer question
[Re: pepin]
#157825 10/21/08 11:41 AM 10/21/08 11:41 AM |
Joined: Aug 2005 Posts: 2,921 Michigan PTP
Carpal Tunnel
|
Carpal Tunnel
Joined: Aug 2005
Posts: 2,921 Michigan | there is no reason why you couldn't do that with an F16, though you should look at your dolphin striker and see how far out to the hulls the V goes. This would make it difficult to put a support there because it would interfere, although there are ways around even that. A lot of A cats don't have dolphin strikers so it is easier to do it with them than other cats. Another issue would be how difficult it is to get the boat on and off the trailer with those type of supports. I would like to do it on mine but don't have that much time to modify it. I also don't generally trailer that much so I don't see it as an issue. The 400lb boats handle the cradles well, the F16 handles it well too though I am much more careful to make sure the rollers in the rear are well padded.
Last edited by PTP; 10/21/08 11:44 AM.
| | | Re: Trailer question
[Re: bobcat]
#158057 10/23/08 03:20 PM 10/23/08 03:20 PM |
Joined: Sep 2005 Posts: 1,187 38.912, -95.37 _flatlander_
old hand
|
old hand
Joined: Sep 2005
Posts: 1,187 38.912, -95.37 | I'm in agreement with Bobcat. An analagy...
My Dad was considered a Maverick, in the early 50's, when he left his V-4 outboard motor on the transom of his boat while trailering. "They" said it'd be laying in the road with the back half of his newly built boat. Everybody took their motors off the boat and put it in the trunk of the car, a two man job.
John H16, H14
| | | Re: Trailer question
[Re: _flatlander_]
#158069 10/23/08 04:38 PM 10/23/08 04:38 PM | Scarecrow
Unregistered
| Scarecrow
Unregistered | I'd advise against supporting any bolted boat by the beams. When you fly a hull the hull is pushing up on the beams not bouncing down a road hanging off them. Hanging the hulls on the trailer will definately soften the composite structure around the beam landings and shorten the competitive life of the boat.
A's can do it because they're A. light and B. Glued. | | | Re: Trailer question
[Re: ]
#158071 10/23/08 04:52 PM 10/23/08 04:52 PM |
Joined: Dec 2005 Posts: 443 Edmonton, Alberta, Canada bobcat
addict
|
addict
Joined: Dec 2005
Posts: 443 Edmonton, Alberta, Canada | I can see where you are coming from....the sidestay is doing the heavy lifting. But then again, so isn't the mainsheet also lifting the beam. So, the bolts are sized for the beam torque, not the weight of the guys standing at the back of the bus?
Is the composite structure at the sidestay that much superior to the structure at the beam landings? Some mode conversion here I guess. The sidestay is in shear, while the beams are compression/tension.
Hanging off the beams while trailering would put the beam bolts in tension, while the normal mode is compression. So, the nuts are at risk of pulling through?
Just trying to get my head around it. | | | Re: Trailer question
[Re: bobcat]
#158080 10/23/08 05:58 PM 10/23/08 05:58 PM |
Joined: Oct 2005 Posts: 951 Brisbane, Queensland, Australi... ncik
old hand
|
old hand
Joined: Oct 2005
Posts: 951 Brisbane, Queensland, Australi... | Hanging off the beams while trailering would put the beam bolts in tension, while the normal mode is compression. So, the nuts are at risk of pulling through? If you've tensioned the bolts up properly, they will remain in tension throughout the usual range of loadings. The bolts are so much greater in diameter than the sidestay wire, it isn't worth thinking about.
Last edited by ncik; 10/23/08 09:37 PM.
| | | Re: Trailer question
[Re: ncik]
#158084 10/23/08 06:39 PM 10/23/08 06:39 PM | Scarecrow
Unregistered
| Scarecrow
Unregistered | Its not the bolts that stop me from doing this on my boats, its the composite structure around the beam landings which will become softened over time due to vibration etc. Also I'm not suggesting that the boat will fall off the beams, merely that its competitive life will be shortened. | | | Re: Trailer question
[Re: ]
#158101 10/23/08 09:42 PM 10/23/08 09:42 PM |
Joined: Oct 2005 Posts: 951 Brisbane, Queensland, Australi... ncik
old hand
|
old hand
Joined: Oct 2005
Posts: 951 Brisbane, Queensland, Australi... | Sorry mate, quote added for reference. You're right, the bolts will not be a problem.
Although to be honest, I'm not convinced the softening of the beam landings is a major concern with a trailer setup like this. Relatively speaking, travel is only a fraction of the sailing time, and sailing would be putting more stress on the area with the torque loads...well certainly where I sail, the chop is nasty! | | | Re: Trailer question
[Re: ncik]
#158127 10/24/08 03:29 AM 10/24/08 03:29 AM | Scarecrow
Unregistered
| Scarecrow
Unregistered | Agreed, but it all adds up. | | | Re: Trailer question
[Re: ]
#158223 10/25/08 10:02 AM 10/25/08 10:02 AM |
Joined: May 2002 Posts: 1,037 Central California ejpoulsen
old hand
|
old hand
Joined: May 2002
Posts: 1,037 Central California | I'd advise against supporting any bolted boat by the beams. When you fly a hull the hull is pushing up on the beams not bouncing down a road hanging off them. Hanging the hulls on the trailer will definately soften the composite structure around the beam landings and shorten the competitive life of the boat.
A's can do it because they're A. light and B. Glued. Never had a problem with my bolted Taipan over several thousand miles on my beam-supporting trailer. I would check the bolts from time to time and they were always torqued as expected. Also, the boat is as stiff today as new.
Eric Poulsen A-class USA 203 Ultimate 20 Central California
| | | Re: Trailer question
[Re: ejpoulsen]
#158231 10/25/08 11:27 AM 10/25/08 11:27 AM |
Joined: Jun 2001 Posts: 9,582 North-West Europe Wouter
Carpal Tunnel
|
Carpal Tunnel
Joined: Jun 2001
Posts: 9,582 North-West Europe |
The hull only weights 23.5 kg (50 lbs), that is not a lot to hang from 2 (or 4) M8 bolts or even a typical laminate work.
Of course the same reasoning can be reversed. I rather hang 23.5 kg from the bolts and the reinforce area around the bolts then press against the (unreingorced) keel line by the same amount.
It is laminate up there, but also laminate down there. So what is the gain/loss ?
Wouter
Wouter Hijink Formula 16 NED 243 (one-off; homebuild) The Netherlands
| | | Re: Trailer question
[Re: Wouter]
#158328 10/26/08 09:40 PM 10/26/08 09:40 PM |
Joined: Jan 2004 Posts: 196 Arkansas, USA CaptainKirt
member
|
member
Joined: Jan 2004
Posts: 196 Arkansas, USA | Can't comment on the other F16's but Jim Boyer, who built the hulls for my and all the older Taipans at least, definitely recommended trailering from the beams- in fact, I was told if you trailered with boat supported on the hulls it would void the warranty even! Jim was more concerned about the boat "racking" during trailering and being "squeezed" by straps over the hulls/beams down to frame to hold boat on the cradles than the hulls "hanging" off the bolts. Jim therefore recommended a stout, heavy steel trailer (softer ride and less twisting) and supporting the boat by the beams. My boat is supported by the front beam at the inside corners but only in the middle of the rear beam (ie a triangle) precisely to prevent "racking" of the boat if the trailer does twist going down the road. Most of the weight of the boat is supported by the front beam- I would guess there is only about 20-30 lbs. maybe being supported by my rear beam in a static situation. If it was good enough for Jim it's good enough for me!
Kirt
Kirt Simmons Taipan, Flyer
| | | Re: Trailer question
[Re: CaptainKirt]
#158358 10/27/08 09:02 AM 10/27/08 09:02 AM |
Joined: Jan 2005 Posts: 6,049 Sebring, Florida. Timbo
Carpal Tunnel
|
Carpal Tunnel
Joined: Jan 2005
Posts: 6,049 Sebring, Florida. | What about this, cover the trailer with plywood, add foam to where the hulls will rest, thus making it like a flatbed type trailer, so the hull is supported along its full length rather than just at two points, front and rear?
Blade F16 #777
| | | Re: Trailer question
[Re: Timbo]
#158372 10/27/08 11:19 AM 10/27/08 11:19 AM |
Joined: Jul 2007 Posts: 976 France pepin OP
old hand
|
OP
old hand
Joined: Jul 2007
Posts: 976 France | What about this, cover the trailer with plywood, add foam to where the hulls will rest, thus making it like a flatbed type trailer, so the hull is supported along its full length rather than just at two points, front and rear? Would maybe work if the hulls were flat bottomed. The bottom of my Stealth has quite a lot of rocker front to back so I'm not sure it's a good idea: it will probably end up with one pressure point in the middle instead of a constant equal pressure all around. You can do that with a Wave or a Nacra 500 maybe, but it doesn't seems like a good idea for my boat. | | |
|
0 registered members (),
615
guests, and 86
spiders. | Key: Admin,
Global Mod,
Mod | | Forums26 Topics22,405 Posts267,056 Members8,150 | Most Online2,167 Dec 19th, 2022 | | |