Someone tell me to leave well enough alone

[InertBert]

So I've been looking into having an arch on put on the transom of my CP16.  The eclipses have something similar to what I was looking at ...



and I noticed that Carry-On has a similar set up on his CP 16 as seen here :



I would like to use this as a mast rest for trailering and some shade attachment points at anchor.  I am most certainly going to build it that far, but then I got to thinking...(this is typically where I get in trouble) what if I had the arch made of some pretty strong stainless and put a traveler rail up there for the mainsheet?  Then I could run boomless on my mainsail, or even convert to a boomless sprit rig(half daydream, half serious).  I could also avoid accidental gybe induced boom accidents by pinning the traveler over to one side.  It'd be a good place for the anchor light and with the mainsheet up high I might not need a topping lift with the sail down.

I guess this boils down to a few questions:  

Does anyone know if having your mainsheet up high is a terrible idea and/or should I try it?  I can always rig it back the way it is and use the arch like normal.  AND, for those with experience with a mast crutch/shade arch, how would you change your setup?  What do you like and what would you change?  I have been talking to a few welding shops and will probably have this built no sooner than late july, so I have a bit of time.

[MacGyver]

Out of all the boats I have seen.... I have never seen a mainsheet up necessarily that high.
I am unsure totally what that would do to the angle of approach especially without a boom.

Interesting concepts...... If I were you I would maybe make a small model on paper and play with it a bit....
That is how I designed my Lazy Jacks and charted out some projects that actually conceptually never made it off paper.... yet.


Interested to see what others have to say.

Mac

[Salty19]

The Com-pac Legacy, the CP16's replacement, has a similar stainless arch with sheet controls on it that you're talking about from the factory. It does have a boom however.



Check it out more with google searches for more pics.

[InertBert]

The Com-pac Legacy, the CP16's replacement, has a similar stainless arch with sheet controls on it that you're talking about from the factory. It does have a boom however.

Well why didn't you just say so to begin with?  That looks perfect.  I will do some searching around and see what people say about the mainsheet handling on such a setup.

That appears to be similar sized tubing as what is used for the bow pulpit.  Do you figure that's strong enough for a dumb sailor in big wind? 

I think if I am careful, I can incorporate this rail with my plan (wife's behest) to add a bit of shade to the cockpit.

If I attempt to mess with the sails or switch to a boomless setup this winter, that may give me more appropriate geometry to outhaul the clew/foot. 

[Pacman]

I would keep the boom.

If the boom is eliminted, the arch will carry a large load from the clew of the mainsail pulling forward.

The boom handles this load so that, if an arch is used to mount the traveler, the primary load on the arch will be in the form of vertical tension when the boom is centered and then moving to port or starboard and a bit forward when the boom is out over the side.

The strongest set up is as it was designed in the original C 16 with a boom and the mainsheet tackle attached to the stern.

[Pacman]

If I put an arch on my C 16 it would only be used as a boom gallows and to support a sun shade.

Maybe I would mount a stern light on it too.

My mainsheet would remain attached to the stern.

[Salty19]

I guess I've never really thought about that type of a system much.
Without actually doing the complex math to determine strength of the system, factoring in angles of brackets, sheet pull, line load, pipe diameter and thickness, etc, etc,  you'll never know if it will be safe in adverse conditions.

I agree with Pacman about keeping the boom.

[Bob23]

Bert:
  Since no one else will tell you, I will: "Leave well enough alone."
Bob23

[crazycarl]

interesting,

our starwind 19 had the mainsheet attached to the stern rail.  it could slide port to starboard some what like a traveler.


i've thought about this on or 19, making the center stern rail a "traveler" with the main sheet tackle fastened to it.

carl

[InertBert]

Without actually doing the complex math to determine strength of the system, factoring in angles of brackets, sheet pull, line load, pipe diameter and thickness, etc, etc,  you'll never know if it will be safe in adverse conditions.

I could trust that ComPac got it at least adequately strong with the legacy and have mine built a bit stronger than that.  Plus, without putting the mainsheet up high, then I will have to have the bimini entirely in front of the mainsheet instead being able to run it farther back. 

I will certainly keep the boom for a while, and I rarely make changes that can't be undone once I figure out how stupid it was.  Although, I have been cutting up an old sail to try out boomless on the current setup, and I am going to bring that puppy out maybe tomorrow morning.  I've looked quite a bit at the geometry and the current setup is a completely wrong angle, but I am interested in seeing how it goes anyway. 

[InertBert]

Bert:
  Since no one else will tell you, I will: "Leave well enough alone."
Bob23

Thank you for that.  I feel like I need a tinkerers anonymous support group.  Its been 26 days since I've taken a power tool to a machine that was in perfect working order.  Which reminds me... maybe I should make some more progress on my proa.

[Bob23]

Trust me, Bert:
    I'm in no position to give anyone advice...I've got a proven track record of fixing things that work perfectly so they hardly work at all when I'm done! I love to tinker. It's like my mind is always racing to find ways to improve things that don't need improving!
Bob23

[Pete H]

Hi Bert,

I have a Legacy which has a stern rail or pushpit, it comes from the factory standard like that so you can assume that they know what they were doing when they designed it as far as strength and diameter of tube is concerned.

The main sheet traveller is part of the design and works well.

The mooring cleats are also attached to it, as is the red stern nav light and a support for the lowered mast. All in all a very well thought out and handy design.

I use it to help pull myself up over the stern when the boat is on the trailer and as I'm no light weight if there were any weakness in the system this would have detected it.

I have a Bimini fitted to provide shade and having the main sheet attached to the stern rail allows for sailing with the Bimini raised.

So, the legacy being very similar to the 16's I can't see why you shouldn't give it a go. Have a look at the Legacy design, you might even be able to get a second hand one to modify, or perhaps you could get Legacy one from Hutchins.

The only downside in my opinion is the look of the thing, to me it seems to look too high and somewhat out of proportion on the Legacy and probably would do so on a sweet sixteen.

Regards,