| Hobie Forums http://www.hobie.com/au/en/forums/ |
|
| Ballast pulley accessory system for the TI http://www.hobie.com/au/en/forums/viewtopic.php?f=71&t=58011 |
Page 1 of 2 |
| Author: | Sunchaser_SWMI [ Fri Jun 17, 2016 11:21 am ] |
| Post subject: | Ballast pulley accessory system for the TI |
So I had an idea, but knowing this forum, I wouldn't be surprised if someone had tried it already. Here's the gist. I would like to create some kind of pulley system that would allow me to shift some kind of a buoy or ballast bag to the high side of the boat. I'm thinking like 50 lbs of ballast that would normally sit against the hull, with the pulleys being operable from the back seat. When sailing in high wind, you could pull on the pulley line and extend the ballast out to the amas, bringing the boat flat. Has anyone tried or thought of something like this before? If so, how did you implement it? Most of the time I sail solo, and prefer sailing from the rear seat. I built some hakas in the past and have a set of trampolines, but then I need to move to the front seat and steering becomes problematic. Not to mention I'm a rather heavy fellow. |
|
| Author: | Tom Kirkman [ Fri Jun 17, 2016 12:23 pm ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
There are larger boats that use moveable ballast systems to do what you describe. The better ones are fairly sophisticated, while older more mundane systems usually entailed nothing more than the crew moving sails and other heavy items from one side of the hull to the other... For the purposes of small boat sailing such systems are generally more trouble than they're worth. Things happen quickly on a small boat and you'll likely find that a shift in your own body location will be the quickest and most practical means of boat trim possible. The most likely problem with a mechanical ballast system is what happens if it doesn't react quickly enough or fails, leaving you the ballast where you can least afford it, and where it may end up doing you more harm than good. Ease, hike, trim. |
|
| Author: | KayakingBob [ Fri Jun 17, 2016 12:42 pm ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
Maybe some type of water tank/bag on each ama/aka using a small pump and tubing to pump water in/out and even between the two. This way, other then the dry weight of the bags, tubing and pump, you launch and land without much extra weight. Maybe even two haka made mostly with pvc pipe as the 'tank'. 
|
|
| Author: | Chekika [ Fri Jun 17, 2016 2:17 pm ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
That is an interesting idea KB! Of course, Stringy would say, simply hike out on the haka for ballast. Keith |
|
| Author: | tonystott [ Fri Jun 17, 2016 4:46 pm ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
Actually, I would question the whole concept. Multihulls gain much o their performance by minimising weight and widening their footprint. Adding weight in the form of ballast runs counter to this. I also firmly believe that due to the ability to partially furl the sail, performance can be maintained even in very heavy winds by reducing sail area. Moving 50 lbs of ballast is going to have a minimal effect in those winds. Also, if you are a heavy bloke, I believe you would be better to sit in the front seat, which turns out to be almost spot on the centre of flotation. I weigh around 300lbs and am very happy with my TIs performance sailing from the front seat. |
|
| Author: | TI_Tom [ Fri Jun 17, 2016 5:18 pm ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
I'm also about 230ish lbs. and I find the front seat as the best balance point as well. I've also found that hiking out on the windward tramp really helps flatten the boat out. Sent from my SPH-L720T using Tapatalk |
|
| Author: | fusioneng [ Fri Jun 17, 2016 5:44 pm ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
Of course you could alway have a little bladder tank on each ama, then have a tilt able hose that you can lower to fill up the tank with your forward motion, the when you want it to drain tilt it either backwards so it's trailing or jus lift it out of the water and let gravity do the rest. However 50 lbs of water is a lot of water, we are talking a 5 gallon pail volume wise, that a lot. You could maybe use large diameter rubber tube so it would fill up like a water balloon, you can probably get a lot of water in a ten ft long 2" to 3" tube. May add a dump valve at the back so you can drain quickly. I actually thought thru all this stuff when I added all the extra sail area to my TI (260 sqft) because the AMA's no longer had enough flotation to keep the boat from flipping unless you hike out on the tramps. What I ended up doing instead was widened the boat by extending the AMA's by on foot on each side. Doesn't sound like much, but just that one foot wider doubles the capsize force, so now my boat is pretty much uncapsizable even with both my 33sqft jib and main full out in 15mph plus winds. Plus the AMA's no longer go under water at all, they just plane on top of the water creating very little drag (if any), the only seem to create a lot of drag when they are mostly submerged. Also because the AKA bars are mounted at an angle, when you move them out, the boat cruises with both AMA's completely out of the water. This ended up being my most bang for the buck mod. FE |
|
| Author: | Chekika [ Fri Jun 17, 2016 7:07 pm ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
tonystott wrote: Actually, I would question the whole concept. Multihulls gain much o their performance by minimising weight and widening their footprint. Adding weight in the form of ballast runs counter to this. I also firmly believe that due to the ability to partially furl the sail, performance can be maintained even in very heavy winds by reducing sail area. Moving 50 lbs of ballast is going to have a minimal effect in those winds. Also, if you are a heavy bloke, I believe you would be better to sit in the front seat, which turns out to be almost spot on the centre of flotation. I weigh around 300lbs and am very happy with my TIs performance sailing from the front seat. Tony is absolutely right. Keep the weight down for best speed. Hiking out on a haka as Stringy suggests will maximize the speed--just be very careful not to fall off or be sure to be tethered to your boat. All my friends sail from the back seat of a tandem Keith |
|
| Author: | TI_Tom [ Fri Jun 17, 2016 7:39 pm ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
Keith, some of us are a little to large to sail from the back seat solo. I found that out the hard way last year when I got stuck at the north end of a lake with a south wind blowing. Until I moved up to the middle the bow rode so high that the wind was just pushing me in circles. Made getting back to the ramp at the south end quite an experience. Sent from my SPH-L720T using Tapatalk |
|
| Author: | stringy [ Fri Jun 17, 2016 8:25 pm ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
Hey Sunchaser_SWMI, Simply hike out on the haka for ballast. (there you go Keith!  )Hiking out is my prefered sailing method, though I understand that it won't suit all. The great thing about these craft are the many sailing position options. I'm so used to hiking out now that I feel very uncomfortable sitting in the seat with an ama buried. Personally I've found the best balance point when sailing solo (I'm 80kg) is opposite the rear footwell. This gets the bow up slightly and lessens splashing. I made my V3 haka to cantilever to the front of the rear hatch:  The flat empty rear footwell is comfortable and makes it easier to swap sides when tacking and the rear X-bar makes a great handle:  I remember a discussion years ago about pumping water into the windward ama, but like Tom K, Keith and Tony I think adding any form of ballast is not really worth the hassle. |
|
| Author: | tonystott [ Sat Jun 18, 2016 2:08 am ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
How good is THAT to illustrate the point! Top job stringy! Pity I am too big a slob to dart around the boat. My ballast stays where I put it when boarding!  BTW Not wishing to hijack the thread, but can you give some details on that unusual camera position? I assume it is attached to the main batten, but then it looks like it can move about a bit.... |
|
| Author: | Chekika [ Sat Jun 18, 2016 2:09 am ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
Good pictures, Stringy! Keith |
|
| Author: | stringy [ Sun Jun 19, 2016 4:32 am ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
Thanks Tony and Keith. tonystott wrote: My ballast stays where I put it when boarding! Tony I was hoping those great looking (and solid) haka you made might be getting a workout sometime? tonystott wrote: BTW Not wishing to hijack the thread, but can you give some details on that unusual camera position? I assume it is attached to the main batten, but then it looks like it can move about a bit.... (Sorry Sunchaser, but I'll be brief.) It's a GoPro rotating helmet mount I made using ideas found here: http://www.diygopro.com/diy-gopro-swive ... -improved/ Based on a swivel castor and using 25mm tube, bimini T-fitting, angle brackets and some PVC pipe fittings, it fits on top of the mast and is secured with an R-Clip. 
|
|
| Author: | fusioneng [ Sun Jun 19, 2016 4:36 am ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
Yea i've always ran a jib and 2ft bowsprit on my TI (only sailed it twice without one and didn't like it). So I'm pretty much stuck in the front seat when solo, plus when you have a jib and big sail sets you pretty much have to hike out on the tramps to keep the AMA's from going under (if you haven't widened your boat yet), I found when the AMA's are mostly buried they create a lot of additional drag, but when they are just skimming on the water there is almost no drag (these boats have a really efficient AMA design if you can keep the bow in the air a little ( IMO). Sitting in the back solo with a jib the bow rides too high and gets blown around too much making the boat difficult to steer. Sitting in the front at least seems to me to be the best ballance point on my boat, plus with tramps and spray skirts It's a lot drier in the front. Also with my TI I have twin outboards that add 55 lbs weight to the rear of the boat, they don't effect the sailing performance of the boat when tilted up but they do effect the balance point (we pretty much need the outboards to be able to cover the vast distances we have to traverse in SWFL and the keys (85% of the time in very low winds). However on a stock TI (which I don't have) with the main mast mounted so far forward 'lighter than me' guys would likely get the best all around performance sitting in the back seat. Getting that bow up and out of the water a little is all important on these boats in my opinion, how you do that is completely up to you. By paying attention to the load center via shifting your passengers and gear forward and back to get the best balance point in my opinion is the best way to get reasonable performance out of your TI. In my opinion one of the best features of the TI is you can sail equally well solo from either the front or the back depending on your own weight and how much gear you have that day. These boats are so versatile it's insane, you can use the crazy things for anything you can dream up (and boy do I dream up a lot, truly the ultimate SUV of the water). FE |
|
| Author: | Sunchaser_SWMI [ Sun Jun 19, 2016 7:28 am ] |
| Post subject: | Re: Ballast pulley accessory system for the TI |
Thanks for all the replies everybody - what a great community we have here! So it seems the consensus is to reduce sail size by furling or hike out. That makes sense. For the folks that hike out - are you using a hiking stick when on the starboard side of the boat? |
|
| Page 1 of 2 | All times are UTC - 8 hours [ DST ] |
| Powered by phpBB® Forum Software © phpBB Group http://www.phpbb.com/ |
|