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Very cool! Ya, I took the plunge about a month ago and bought a sailrite ultrafeed. I am flirting with a bunch of small canvas projects but I haven't actually done one yet other than run some test seams through the machine. It's a beast though, can do leather or like more than 8 layers thick of outdoor boat canvas. I think your project looks great though, awesome that you just found a way to get it done.

I saw a ton of pictures on social media groups of people up that way laying the wood to lings after you posted this. Guess they were bitin' huh? :D Nice fish!

This is really pretty incredible. Chuck is the man. The weather down here has been pretty ripper, although it's probably just another day on the water for all you northerners. 1300+ miles of it sounds really daunting, I can't even imagine. :) Pretty freaking cool.

General Discussion about the Great Alaskan / Re: Bow thruster install
« on: March 22, 2023, 09:59:51 PM »
That's going to be a tough first cut to make.... :o

Measure 10 times, cut once!!

No doubt. :) How many double and triple checks does it take to make sure the hole is in the right spot? Certainly never feels like enough in cases like this...

General Discussion about the Great Alaskan / Re: Bow thruster install
« on: March 21, 2023, 02:20:25 PM »
Cool. Ya, for the shape of the hole I intend to cut a center-hole on both sides, then put a rod through them that has a sharpie attached the tube's radius from the rod. That should allow me to accurately trace the shape of a circle transposed onto a curvy hull since the rod can slip side to side but not off of the center-point. Maybe I will make a video of the journey and share if it doesn't suck after I do it lol. Or maybe if it does suck I can title the video 'what not to do when installing a bow thruster' :)

General Discussion about the Great Alaskan / Re: Bow thruster install
« on: March 21, 2023, 10:06:23 AM »
Thanks Brian! 18" is a good amount to play with, I think I should be able to find a good compromise in there. Can you include details on how to locate the initial tube in relation to the keel or other hight reference so I can use it to make sure I don't locate the tube too high? I think I should be able to eyeball not getting into the fillet or tape on the keel but I want to make sure I don't put the tube out of the water either. I can probably figure out how to translate the original measurement forward too, so if you have something there that I could use that would be super helpful!

I basically hit the bunks and then just crank until the bow eye is right above the winch, and then pull it bit by bit trying to get the stern positioned right. I think your front bunks are way shorter than my front bunks, and I have mine set up a fair bit wider I think than yours (at least judging from the pic where you were putting your boat on the trailer). I wonder if you should get longer bunks up front.

General Discussion about the Great Alaskan / Re: Bow thruster install
« on: March 17, 2023, 02:26:33 PM »
I will reach out to their support and ask. A smaller tube allows the installation to move forward right? Doesn't have to be as long, doesn't have to have as much vertical space to work, also more torque generated if it's further from the pivot point...

General Discussion about the Great Alaskan / Re: Bow thruster install
« on: March 17, 2023, 08:38:34 AM »
They make a thruster with a 4 5/16" diameter tube, with 62 lbs of thrust -

Is that worth checking out?

General Discussion about the Great Alaskan / Re: Bow thruster install
« on: March 16, 2023, 09:28:00 AM »
Ah, interesting. Ok, thanks for the info Brian, seems that the balancing act is a little tighter than I thought. Let me see what I can do to make this work as designed. I appreciate you taking the time to help me see the light.

General Discussion about the Great Alaskan / Re: Bow thruster install
« on: March 15, 2023, 04:31:18 PM »
I spoke with Lewmar's customer service rep, and gained a bit of additional information that was good. He didn't answer my questions though really, but searching around I feel like I have a somewhat ok grasp on what the trade-offs are. The relevant part of his response (where he wasn't telling me that I need to have a professional shop install it) is this:

"The further away from the barycenter the thruster is the more leverage it will have to push the bow (or stern).  The tube needs to be far enough below the water line so that the exit water does not interact with the surface or thrust will be lost.
At the same time you have to keep the tube far enough away from the hull bottom so there is enough strength to prevent it from breaking."

I also found this document that details lots of things around tunnel thruster installation:

The question that seems like biggest shortcoming of installing the tube forward of the cad drawing is that the length of the bottom of the tube might be shorter, and might be closer to the surface and/or closer to the keel. The recommended length of the tube is 2x the diameter of the tube, diameter being 5.5". I was reviewing Chuck's install, and just ball-parking from the pictures it doesn't look like his tube is 11" long. I did speak with him about it though and he said the system works great.

So, couple more questions for you Brian. 1. Do you have the shortest length of the tube as designed in the cad drawing? 2. How close can the tube be installed to the keel to maintain structural integrity?

General Discussion about the Great Alaskan / Re: Bow thruster install
« on: March 15, 2023, 09:49:32 AM »
The docs state that the length of the tube should be 2x the tube diameter (which is 5.5" or close to). And actually, let me just include the relevant part here for the sake of discussion and future builders possibly doing research:

The actual position of the Thruster will depend on the internal & external construction of the Motor Boat or Sailing Yacht. For optimal performance the Thruster should be mounted within the following:

‣ As far forward as possible (Fig 3.1.1 / lever effect).
‣ 1 x below the waterline to prevent air being sucked into the tunnel. (Fig. 3.1.2 / 0.75 x minimum.).
‣ Minimum suggested tunnel length 2 x .

NOTE: Ensure there is sufficient space for the Thruster assembly complete with motor and controls in the boat.

= Tunnel Diameter

I had posted about the jet thruster not too long ago, it looks like a really cool option but was also going to take some work to get to fit well. If my memory serves the power consumption requirements were really heavy for that as well (it needed a battery capable of something like 500 cold cranking amps, so would have most likely required me to install a dedicated battery and all that entails). I contacted Lewmar support for clarification and additional feedback about their suggestions. If/when they get back to me I will update this with anything relevant.

General Discussion about the Great Alaskan / Re: Bow thruster install
« on: March 14, 2023, 01:54:48 PM »
Thanks Brian. I could put the tube where the drawing shows, but I would probably be losing most of, if not all of, the floor space in the cuddy. If I could move it maybe 12-18" toward the bow it would make that a lot less. I could also move it aft about a foot but then I start running into the stringers so I don't think that's going to work. I would like to keep at least enough floor space in there to keep the head in there (a 5 gallon bucket with a seat). So since moving into the dead space inside the crash chamber isn't really feasible, maybe making another space just aft of the crash chamber could work. Definitely curious to hear your thoughts.

General Discussion about the Great Alaskan / Bow thruster install
« on: March 13, 2023, 01:59:57 PM »
I am going to be installing a bow thruster at some time in the near future, and was reviewing the images in Grady300's build thread of the cad drawings that Brian did for his install. I put my crash chamber bulkhead too far forward to use the measurements in the drawings, so, I have a couple questions around it.

Is there a hangup putting the tube further toward the bow? I believe there is a minimum width of the bottom of the tube, so as long as that requirement is met, and the minimum depth of the tube is also met under the waterline, is there any other reason that the tube needs to be located further aft as in the drawings?

If the tube is far enough forward such that the back of the tube becomes a perpendicular face toward the direction of the boat traveling, is there any reason to reenforce that back edge and round it off so that the water would flow off toward the outside of the tube?

I am attaching the drawings from Grady's build thread for reference.

Blog, New Designs Discussion / Re: What boats?
« on: March 09, 2023, 01:09:21 PM »
On my run this morning I was also mulling over how cool an offshore catamaran would be as well. Something approximately the size as a GA, probably with more beam, but set up with a walk around house and cuddy would be killer. Even a smaller center console sized cat would be awesome too...

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