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A No-Modifications, FlexiBoom for $14.95
http://www.hobie.com/au/en/forums/viewtopic.php?f=69&t=53647		 Page 1 of 2
Author:  vetgam [ Thu Jan 08, 2015 7:00 am ]
Post subject:  A No-Modifications, FlexiBoom for $14.95
Slaughter introduced the FlexiBoom idea a while back and I had been hesitant to implement it due to the mods needed at the mast base and main clew. I decided to go forward with it with my AI and in doing so I was unexpectedly able to rig a no-modifications version.

Here is Slaughters original video demonstration that shows the extra downwind speed his FlexiBoom creates. (It's an brilliant idea Slaughter!)



Here is where I ordered the shock cord tent poles- important to get this one for the no-modifications version.

http://www.amazon.com/gp/product/B00M7B ... UTF8&psc=1



The idea is that these tent poles have a bend at one point in the pole. We use this bend to our advantage. You will get two separate poles already assembled with shock cord inside. You will need to remove a few pieces at each end and put one half hitch in the shock cord at the mast end and create a loop in the shock cord at the clew end. (See pics) No sawing of the poles is necessary (at least on the AI). Poles may be long enough for a TI but not sure. The key is to use the bent end at the mast and instead hooking it into a fabricated dowel clamp on the mast, you just remove one of the crossbar screw plugs and set the short bent end directly into the hole. It hold the FlexiBoom firmly and the bend in the tent pole allows the Flexiboom to rotate easily. You will notice this creates a nice contour of the FlexiBoom in relationship to the foot of the main.

At the clew end, the loop that you made passes through the small loop in the stainless steel hardware- that you already have at the clew and that connects to the main sheet. Once you pass it though the hardware loop, then pass the stretched loop back over the end of the tent pole. (again, see pics) Now, when you go to take down the FlexiBoom, you just lift it out of the crossbar and pull the clew end towards you and it automatically releases. Although I have not had a chance to get it out on the water, it worked well in a dry run on a windy day in my yard.

Here are the pics (sorry, I don't know how to make them smaller)

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Thought others might like this.

Greg
Author:  Salty Dawg [ Thu Jan 08, 2015 8:26 am ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
Great idea !
I'm kinda wondering though about what happens when you have to reef or furl the sail ?
Is it a quick disconnect at the end ?
Author:  vetgam [ Thu Jan 08, 2015 8:40 am ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
Both ends disconnect instantly. Just lift the mast end out of the hole and pull the flexiboom forward to disconnect the clew end. You can do this literally in less than 1-2 seconds. Then reef. The beauty of this is the ease of removal as well as deploying. Tent poles fold as seen in Slaughter's video.
Author:  vetgam [ Thu Jan 08, 2015 11:06 am ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
I'm rethinking the connection at the clew. Movement of the sail could cause chafing of the shock cord over time where it exits the rod. Instant FlexiBoom disintegration. Slaughters clew attachment might be better. The concern i have with Slaughters clew is that i don't like the idea of a metal piece dangling at eye level when not in use. I could stick with my method but apply an acrylic to the edges of the tubing to prevent chafing.

Greg
Author:  Slaughter [ Fri Jan 09, 2015 4:04 am ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
Great work Greg. So glad you have been able to grab the idea and run with it. Have you been able to test drive it yet since your last post ?

I've had a great run with mine however I am really cautious when I use it. I tend to only use it in our light downwind easterly conditions. Our westerlies can be extremely gusty so I make sure in those conditions it's always tucked away, out of sight, out of mind. :wink:
Author:  vetgam [ Fri Jan 09, 2015 6:48 am ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
Have not had a chance to use it yet Slaughter. When you see the FlexiBoom on the boat on it becomes real just how much of it difference it is likely to make. I had planed to be carefull with its use in anything other than mild winds.

Curious about two things. One, have you broken rudder pins while using it? Two, does that piece of harware at the clew that your using stay there all the time and do you ever get hit in the head with it?

Oh, and do these tent poles rust over time?

Greg
Author:  Slaughter [ Fri Jan 09, 2015 12:26 pm ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
Gee Greg, so many questions, it's 6 in the morning here and my brain hasn't kicked into gear yet :shock:

Nope, no rudder pin breakages yet. Because of the light conditions I use it in, the loading will hopefully never exceed the loading the pin takes under full sail.

The hardware at the clew is just another of those standard 'S' shaped fittings (whatever they are called ). So I have 2 of them attached together and the end of the tent pole ferrule ( joiner ) slots into it. That's my quick connect. It hasn't hit my head yet, no more than the sheave block in the same spot.

Yep the ferrules are made from mild steel and poorly coated so they do rust. I'm going to replace with stainless when I get a chance. The poles themselves are fibreglass so not a problem.

Keep us updated with you testing :wink:
Author:  stringy [ Fri Jan 09, 2015 4:03 pm ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
Nice work Greg. You should have no corrosion issues. Your poles are powder coated aluminium and were a real bargain. I tried to order them but they won't deliver to Aus. :(
Out here those poles would have cost a lot more.
Author:  vetgam [ Sun Jan 11, 2015 2:51 pm ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
I played with the clew attachment and think I have a reasonable solution. I just lengthened the loop in the shock cord and when you apply lengthwise pressure the cord does not seem to pull out and chafe on the tent pole opening. You just have to play with different lengths of the loop. Below shows the proccess of attaching a releasing the FlexiBoom at the clew. In the video, you have to imagine that the loop I make with my index finger and thumb is the grommet in the clew. Sorry, low quality video.



Greg
Author:  cosybike [ Sun Jan 11, 2015 6:47 pm ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
I had a tent with powder coated alu poles that got salty over a weekend. They failed quite quickly shortly after.

Fibre glass rod or a carbon roach pole could also work.
Author:  vetgam [ Sun Jan 11, 2015 7:14 pm ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
Any way to bend carbon fiber or fiber glass? I would imagine the only answer is to joint two ends with acrylic material at the required angle to allow you to use the screw access hole I the crossbar.

Once I get these aluminum rods into the saltwater, I'll report back.

Greg
Author:  tonystott [ Sun Jan 11, 2015 10:00 pm ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
I reckon my middle name should be McIver, as I can't help thinking that my idea of filing a small groove in the end of the Hobie paddle, which can catch one of the knots on the string dangling from the clew of the mainsail, is easily the simplest solution for holding the sail out when well off the wind..., to be honest, I very rarely sail almost straight downwind because it is boring! Far more fun to sail at an angle and pick up increased apparewt wind. You will just about arrive at the same donwind destination at the same time, but with a grin on your face!
Author:  vetgam [ Mon Jan 12, 2015 11:03 am ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
Tony, you do win the McGyver award for that one. I likedyour idea and have been using it for a couple years now. It does help but I have not found and easy way to set and forget. Plus the FlexiBoom video that Slaughter produced looks as though he is getting more speed from the Flexiboom. The FlexiBoom is set and forget and it appears to hold the sail out more effectively than my paddle does. I can compare yet because I haven't test drive the FlexiBoom yet.

If the FlexiBoom works better, I'm going to let the two of you fight over the McGyver award. :D

Greg
Author:  Slaughter [ Mon Jan 12, 2015 5:08 pm ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
Hey Greg. I like the attachment knot. The bungee cord will give the sail a bit of give which is possibly better that my fixed connection. With your design, you will need that, due to the geometry being different to mine. On your FlexiBoom design, when the sail is reefed, the pivot point to the clew is a different length than the base of the sail at the mast to the clew. But it would be approximately the same length when the boat is running downwind. But then again in looking at your second last photo, the distance looks pretty much the same so I may be talking out my arse ( again ). Hard to explain in words but hopefully you know what I mean. Looking forward to seeing the results from the sea trials.
Author:  vetgam [ Tue Jan 13, 2015 6:42 am ]
Post subject:  Re: A No-Modifications, FlexiBoom for $14.95
Slaughter, I understand. It works fine (at least on land) on a port tack as well as starboard even though the mast pivot point is slightly offset. Probably due to the stretching and relaxing of the bungee in combination with the mainsail pulling in and keeping tension on the FlexiBoom.

My biggest concern is that the FlexiBoom doesn' t unexpectedly disconnect at the clew with accidental jibes and sail motion. The bungee loop can probably be adjusted to avoid this but I may need to experiment with it a bit on the water.

Greg
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