Build Blog, my Hobie TI (3) 2017 project

Thanks for the pos feedback John! Appeciate the "Like"

Friday at last and a full weekend ahead! Dont you just live the feeling?

I am having a grate time doing the build. Geat fun!
I will be continuing the build tomorrow. Lots to do this weekend...

1. Attaching the extra rear akas and mount them. Maybe I should paint them black to match the stock akas?
2. Add some new rod holders. Got some new RAM Tube JR I want to try.
3. Make some straps for the haka benches for a secure fit.
4. Continue with the sonar transducer mounts and try to get them ready for action.
5. Try the new RAM mount for the VHF.
6. Set up the anchor reel and line with the quick-release system.
7. Mount the anchor trolley.
(Hope I can get most of this done this weekend )

On sunday I am heading out fishing again... I hope anyway... the forcast looks very promising.
It will be the first longer ride out with both sail and 4-stroke, very exciting!
Looking forward to a nice day out on the water again.

The fishing season is coming to an end way to fast this year. Winds are picking up more and winter is coming with temps dropping. Mornings are getting cold already but no temps below zero and no frost so far.

Thailand sounds very nice... sunny and warm!

_________________
Sailing my TI and fishing.... thats bliss!!

Nice job on the SST brackets for the fighting chair Gustav.
How in the heck did you fabricate those to get such a fair curve out of that square tubing ?
I'm enjoying your project progress despite not being a fisherman,,, yet.

Chris

Greetings Chris! Thanks a lot Mate!
About fishing you better watch your self its kind of contagious!
I was struck with "CAS" in my early years, Chronic Angling Syndrome, no cure!! LOL

Oh... the SS brackets for the chair looks ok, not very complicated really just some cutting and grinding.
I cut out the bracket first in a straight line leaving a "tounge" of metal and then clamp it down in the vice and bent it over a tube with the right radius. The good old sledge hammer and some cursing helped a bit!
I am pretty sure anybody can do a mod like this but it sure takes a lot of time.

I am just in for a quick coffe, been at it since 6am, (I am an early bird most days).
Finishing up the mounting of the extra akas in the rear. Nice to finaly see them mounted.







The setup with the angled akas feels ok. With tramps mounted both front and rear between the akas it will be so much easier to move about on the yak and to get out to sit on the haka benches.
(Getting out of the rear seat to get up front in a stock TI is accually a bit tricky. )

I will hot glue the tubes into the aka hinges to keep it from ratteling around. The aluminium tubes I could find was only 40 mm and the Hobie stock aka tubes are 1 and 5/8"?! 41,3 mm is not a very common dimension in the rest of the world! Go Metric USA Go Metric!!
Anyway I hope some hot glue before I put the pop rivets into place will do the job just fine.

Well coffy brake over! Back to the workshop!
Se ya!

_________________
Sailing my TI and fishing.... thats bliss!!

I don't know about hot glue but a marine sealant like Sikaflex 291 does work well. See mine and Mingles post's here:
https://www.hobie.com/forums/viewtopic. ... ex#p268220
Mingle didn't even bother with the rivets as the marine sealant bond was so strong.

Thanks for the tip Stringy!

Sikaflex would sureley work very well but it would be very hard to remove the tube again if needed.
The hot glue just adds some spacing for the aluminium tube that is a bit to small. The rivets will keep the tube from sliding or rotating.
If I need to change the tube in the future i drill out the rivets and just take the heat gun and warm up the tube and it slides out. Easy as pie!

Packing the fishing gear right now....
I am really exited. First trip out ever tomorrow with both sail + outboard and also the haka benches mounted. Forecast promises a nice day with windforce around 6-8 knots.
I will try to get some fotage, stills and video!
Goto hit the sack!
Wish you a great Sunday Mate!!
Se ya!
/Gustav

_________________
Sailing my TI and fishing.... thats bliss!!

This weekend I fabricated the railplates for the rodholders on the rear extra aka arms. I will have 2pcs of RAM C-balls for rodholders on each side making a total of four possible moutingpoints.





Maybe I will also mount a couple of real heavy duty rod holders on the 4-stroke motor-crossbar, still deciding about this.
The setup will give a pretty good "spread" of about 5 meters wide when trolling. Good only knows what will happen if I get "slammed" with 3-4 or more salmon at the same time!!?? It will be a mess for sure trying to handle that all alone!! But it will give my viewers a real good laugh!

I took a day of from the build yesterday and guided a kayak fishing buddy to some spots in Oresund (the strait between Sweden and Denmark).
A great day with nice weather in the morning. Some nice fishing, herring and mackerel. Very veak winds but we were drifting mostly. My friend Niklas had been teasing me before the trip that I would not to be able to keep up with his revo 13... he didnt know I had an outboard!!
I ran circles around him with the TI when we were heading out! (a little sailing to once the wind picked up)




As the day went by storms were slowly building on land on both sides of the strait and we decided to head back in. We had been drifting a bit further then enticipated so when thunder and lightning was eminent and started to hit in land I took down the mast and started the outboard. It really saved our little buts and we got in safely. (I will post som video once I edited the clips)
A good investement for sure to have an outboard!

Well its monday again, I will try to press on with the build best I can. I made a list once I got home today after work and noted 53 things to adress!!!
Phew!!
My old fishing byddys (not kayakers) are correct, they warned me, kayaking is hard work!

_________________
Sailing my TI and fishing.... thats bliss!!

Wow, just stumbled upon this thread today. You've done some very unique mods, very impressive and paradigm changing. Looks like fusioneng now has some serious competition for radical, innovative modifications.

I'm also intrigued, but a bit perplexed, by your bold selection of a 5 HP motor for use on a TI. I recently published a TI Outboard Motor Application Guide. It never occurred to me to use such a large, heavy, powerful motor for the TI because I felt even selecting a 39 lb (17.7 kg) 3.5HP Mercury was pushing the limit over the smaller, 29lb (13kg) 2.5 HP Honda and Suzuki. Having owned the larger, heavier 3.5 HP Merc I would now not recommend it. I certainly never would have been so bold as to select the 5HP Merc at 57 lbs (26 kg). I would have thought that both the HP and weight would put too much stress on the TI's plastic hull (the TI is rated for only a 400 Watt (0.5 HP) motor).

When unsupported weight is placed on the TI hull aft, a dimple will form on the bottom of the hull about 1/3 from the stern. This may eventually happen even to those who use Hobie Cradles rather than something like PVC pipe supports for a trailer because the weight of the aft end is not well supported, and this is without a heavy motor. With a motor, this might eventually cause hull damage which is why I suggested to everyone using a gas outboard to ensure the motor's weight was relieved when not on the water. Additionally, my 39 lb 3.5 HP Merc caused a considerable list which I found disturbing. At 57 lbs the list must be even more severe. Finally, so much weight aft tends to sink the aft end deeper into the water. If the weight is not balanced up front this may cause fore/aft balance issues.

I'm not saying a 5 HP motor couldn't be used, but I personally would not recommend it. There's a lot of excellent material in this thread to copy, but I hope new TI owners reading this don't copy the use of such a large motor. A 2.5 - 3.5 HP outboard motor is all or more than a TI needs. Even better suited to the TI, the Torqeedo 403 15 lb electric motor will suffice for most.

One thing I do like about the 5 hp is that you can use an external tank with it. If you typically motor over 10 miles and want to get somewhere fast (9 knots is hauling axx in my book), that might be a nice option. 3 gallons of gas will have huge range.

That outboard can also be equipped with a DC charging system. A 7 inch chart plotter used by a lot of fishing folks might use on the order of 0.7 amps and even the fairly weak charging system on that outboard easily supplies that plus will charge a battery.

But.. outboards are an easy target for thieves. The 2 to 2.5 hp outboards at just over 30 pounds are fairly easy to put on or remove from the mount or carry around. I have that same outboard as the 5 hp but in the 4 hp version and at nearly twice the weight, its not something I would want to move around as much as I move the 2.5 hp around. Maybe if I were 20 years younger my back would not mind so much. Considering everything.. I have to agree that 2.3 to 2.5 hp is about perfect for this boat.

Hello Mate! Glad you like the project. Appreaciated!!
Everyone on the forum has been very inspiring. I learned a lot from reading and looking at all of your builds but I also have a lot of ideas of my own that I have to "put to the test". So I hope some of my "mods" might interest others.

Thanks for the input about the larger 4-stroke. Very wise words and I am well aware of the stress I will be putting on the TI hull and did take this in consideration when designing the motormount the way I did.

The motormount is securely fastned in the two 75cm (2') long rails on each side of the gudgeon so that spreads the stress a lot. The gudgeon also seems to be rather sturdy. (some areas of the hull is really very weak)
Underneath the rails (inside the hull) two long square tubes acts as very large washers. Everything is mounted with a fair amount of Sikaflex that has a semi-rigid structure so at the end points of the rails/"washers" there is no sharp transition of force/load that otherwise might stress the plastic forming cracks in theese places.
I will off course not transport the TI on the trailer with the 5hp motor mounted. I already have some dimples from the cradles without ever transporting it with the motor mounted. (I will shortly adress this issue, straighten the hull and makes changes on my trailer soon. Pvc tubes seem to be a better sollution.)
The beachweels are mounted ("blocked") togheter with the motormount so when the TI is rolling on the rear beachwheels the hull is not pressed down by the motor at all. All the weight from the motor is transfered directly to the beachwheels. The hull is accually hanging in the 2 long rails when using the beachweels. I will mount a strap to lift and support the hull a little and this will also stabilize the wheels. I am still working on the beachwheel setup/design but I have a pretty good idea how to get it to work right.

The sea conditions must also be taken in consideration when pushing harder on the TI hull with a bigger motor. If its flat all is well but waves and rolling/bouncing gives a lots of extra stress so off course I throttle down a bit. The good thing is... most times when the motor will be used its beacuse of lack of wind.... yup... no wind mostly means calm waters.

So at the moment I am not especially worried about damaging the TI just because of the larger outboard. All seems good.

I have been running for about 5 hours now with 50%-75% trottle (at about 9 knots). No signs of damages on the hull but I will off course continue beeing observant for cracs or deformation. The motormount does not flex ot move around at all so that is a good sign I guess.
As I wrote earlier in the thread (after the first testride), a 2,5-3,5 Hp would be plenty in most cases but I really wanted an engine with external tank, reverse gear and exhaust thru the prop.
Concering the weight, the 10 extra kgs is no issue on the water, the TI can handle the weight if the weight is well dispured as with my setup. The list is accually not bad at all and the hydrofoil wings seem to straighten the TI a bit when using the outboard. The weight is more a "backbraking" problem when lifting the motor on land. Phew, 10 kilos extra is a lot when logging it over the beach. I will probably make a little cart for the 4-stroke to save my back. I allways attach the motor to the mount when I already got the TI down on the beach or or in the water.

But I fully do agree with you that as a general recomendation a smaller motor is much better choice for most users.
I have seen a lot of examples of motormounts that I would not dare to use even with a smaller motor so good thing you summed it up in the guidelines, very well done!!

I am still messuring the fuel consumption of the motor.It has just been broken in. It seems to use about 1 liter of fuel an hour when going half trottle (~9knots). If I messured this correctly the 12 liter external tank would give me a range of about 110 nautical miles ~200km (125miles) so that would be pretty awsome. I will have better data in the future once I get the Plotter mounted.

And I am NOT competing with fusioneng!! (but I appreciate the comment, I am very honoured but do not feel worthy)
That guy has really done amazing stuff with his mods. I will never get the level of experiance and time on the water in the TI as he has.
I just love his double motor setup. How cool is that!!
And his furling jib -wing/spinnaker setup... really awsome!!
I will be looking into a furling jib in the future so I will take a closer look at his build when the time comes.

It sure is fun messing around with theese great kayaks!!

All the best!
/Gustav

_________________
Sailing my TI and fishing.... thats bliss!!

Hi Walt!
Yeah I will be messuring the fuel consumption and have better data in the future but the first signs are very promising. So the external tank is a great thing. But I guess most smaller engines could be modded to support an external tank with some hose and a valve.

Hauling the 50lbs 5Hp Merc is the worst part. Will be building a little cart... my back has passed the expiration date...

_________________
Sailing my TI and fishing.... thats bliss!!

Anchor setup...

The YakAttack trolley system is a bit dissapointing. The plastic feels a bit week and flimsy. I am mostly worried that th D-Ring will brake when anchoring in stronger winds. The TI has a huge winddraft (because of the mast) compared with regular kayaks. I decided to mount the system anyway, the rope guides are very smart and should keep the line in place and the rope quick stop lock seems vey practical. if the D-ring brakes I will make a new copy of it but one made of stainless steel instead. I will not use the plastic YakAttack pulleys on my TI. I will mount the plastic pulleys on my little china kayak instead. I have steel Harken pulleys (same as the sheet line pulleys) that I will use instead on the TI for the anchor trolley.



I have three different anchors:
1. A very tiny 0,7 kgs grapnel type anchor with a plastic dive reel. I plan to use this in very weak winds or as a second anchor to align the TI in some situations to keep it from swinging/rotating around the main anchor so that the motions is making stationary angling difficult.
2. A grapnel type anchor 2,5 kgs with 2 m chain for hard bottoms
3. A plow anchor 2 kgs with 2 m chain for soft bottoms.





On the D-ring on the trolley line I have attached a snap shackle. I have tied a 6 liter boi to the big stainless dive reel that is then snapped onto the snap shackle on the trolley line. From the rear seat I will run a release line to the snap shackle to quickly enable to release the anchor if I get a big hookup. Just a quick pull on the release line and I am drifting freely leaving the boi with the divereel floating at the anchor point.



When putting the anchor down its important to mark a waypoint on the plotter. A small boi is otherwise extremely hard to find on open water... would be sad loosing my brand new divereel.

I will also mount an anchor roll on the rail and add a cam cleat to make it easier hoisting up the anchor without scratching up the side of the kayak.




Tomorrow I will check out the best placement for the anchor roll and where to mount the PVC tubes that will store the anchors.

I will for sure use the Xi5 electric motor gps anchor lock a lot but a regular anchor is very useful and also an important safety feature.

All the best!
/Gustav

_________________
Sailing my TI and fishing.... thats bliss!!

Retired guy (me) must be a little bored this morning ... but I played with some numbers given my peak speed with a 2.5 hp outboard and Husse0416's peak speed with a 5 hp outboard.

Listening to H's video, I think the 5 hp outboard was running up into the proper RPM range for peak HP and not rev limiting. So Im assuming that both he and I were getting in the range of the rated HP. He did not have the mast on (I did) and I dont know if the pedal drive was in place (mine was) and his boat is a little heavier from the add on.. but its a close enough comparison. In both cases, one person in the boat sitting in the back seat.

H didnt give the exact peak speed (a little over 9 knots) and for this little exercise, I assumed H's peak speed was 9.3 knots. My peak speed was close to 8 mph or 6.95 knots.

We know that hull drag follows a square law with speed at low speeds and then the exponent increases at higher speeds for a variety or reasons. Anyhow, we have two data points and in this case, assume an exponential equation for curve fitting the two data points. For sure a linear equation does not work for this case.

Details available if someone wants but the exponential equation that fits those two data points is

Speed (knots) = 6.956 * ((hp/2.5)**.4188 )

Note that a square law would have an exponent of .5 and a cube law would have an exponent of .333. So on the TI, the speed vs hp required for that speed is somewhere in between square and cube.

Using this equation, I plugged in some different HP numbers to see what speed would be predicted. Note that the numbers for 2.5 and 5 exactly match the real data.

HP / Knots
-------------
.625 / 3.89
1.25 / 5.203
2.5 / 6.95
5 / 9.3
10 / 12.43

That equation only is accurate near the two exact data points at 2.5 and 5 hp but its somewhat interesting to look outside the range. Defy here https://www.hobie.com/forums/viewtopic. ... 8&start=45 was getting 5.1 mph with the 400 watt Torqueedo at peak power (didnt post what power the control said was being used, that would certainly be interesting). Note that the equation based on the 2.5 and 5 hp data points predicted that 466 watts (.625 hp) would only get up to 4.47 mph or 3.89 knots and Defy was going faster than that. I take that to mean that at the lower speeds, the exponent goes back closer to square law of the typical parasitic drag vs speed equations.

Also.. its likely that the equation over estimates the speed for 10 hp as the exponent is probably lower for 10 vs 5 or 2.5. But I think its fair to say that you will not get speeds over 12.43 knots or 14.29 mph if for some crazy reason you did put 10 hp on a TI.

Ok.. back to doing something more useful (or maybe defending all that junk.. which could be incorrect).

I will have to take some pics of the controller next time i am out. But i pretty consistently get about 5mph at full throttle.


Sent from my iPhone using Tapatalk

I'm waiting for the chapter of Husse to start boring out the hull for more storage space

I'd never do anything like this to my T.I. but it sure is entertaining to watch from my "dry" desk.

_________________
2017 Tandem Island in Red. Lake sailing/kayaking in NH only.

Late evening here in Sweden. Just got in from the black autumn night. Finaly mounted the anchor trolley and drilled 14 new little holes in my kayak!! Starts to feel like I will be sailing a Swiss cheese!

I just lightly tightened the bolts untill the Sikaflex sealent sets. Tomorrow I will tighten them fully and mount the trolley line and se if it works ok. Its a long trolley setup 5,2 meters so I hope it will work. The line guides from YakAttack looks promising and the leverlock seems practical but I have never tried one of theese trolleys before.
Its to dark to take any pics tonight but this is the hardware before mounting it.



I did not use the original yakattack black plastic pulleys or the mountingplates. The moulded nuts in the YakAttack plates are of course not metric but imperial instead, 3/8" or something like that. I changed the bolts to 5mm and used 20mm washers on ghe inside all around. I hope that will work and be strong enough. Plenty of Sikaflex as usual to keep it waterproof and to protect the plastic in the kayak.

I changed some of the thick washer plates on the front motormount. They were unnecessarily thick (6mm) and heavy so I made 2mm plates instead. I saved 300 grams!! Wohooo!!
But I kept the left plate as before and welded on a tounge for a Harken pulley to re-route the furlingsheet. Unfortunately the pulley sits a bit to low so when taking out the sail and the furlingline spols up it jams underneat the roller on the mast.
I will weld on an arc or a small roller to lift the furlingline a bit to make it spool up correctly.




The furlingline will run along the port side and go through a couple of line guides back to the rear seat and then into the automatic line dispenser at the port side of the rear seat.
I hope I can get the new furlingline setup done by tomorrow afternoon and then get on with the transducermounts.
I have most of the pieces ready for welding. I changed some minor details on the design so I think it might work ok now.

New weekend ahead! Friday!!

_________________
Sailing my TI and fishing.... thats bliss!!