A quick search for opinions...

[Dieselram94]

Everything sanded and prepped. Possibly going to try to glass it in tonight!

[nebulatech]

I've got my fingers crossed for you!

[tribologist]

Here's my bow thruster install...

IMG_1344.JPG

The tube is straight but you can see how it got thicker at the end with my laminations to the hull. Almost like an hourglass.

I also first put a 3/4" radius fillet of thickened epoxy as a starter to bond the tube in place before I started with the laminations. Small strips first, then built up to larger strips with each lamination. I finished just by brushing gelcoat over the thing to make it pretty.

Told you I was a glutton for punishment.

What kind of thruster did you end up installing? I started to look at them after our long trip. There were a few hairy moments in very close quarters that would have been a lot nicer with a little bow kick. A Lewmar 110TT is under a grand and is rated to 62 lbf. More would certainly be nice but the cost starts climbing fast with larger units. I seen some people on the Swedish Albin 25 forum install them behind the water tank. It looks quite easy to put it in there assuming the tunnel for the 110TT is long enough.

Ulf

[hetek]

I installed a Side Power SE40. It uses a 5" diameter tunnel, which is the same tunnel for the smaller SE30. I also bought the far superior joystick control, rather than the push button version.

Bought everything at Defender Marine on a day trip to CT.

There is also a bow thruster shop in RI, I believe, if you didnt want to do it yourself.

Thrusters need power (duh!), but wiring them is a bit tricky. Two options: wire to the house/starting batteries and run 00 cables to the bow, or... install a dedicated battery and charger in the bow next to the thruster.

I did the cables to the bow method. The RI shop does the battery forward method.

Hope this helps.

[hetek]

Actually, it's not RI... it's Groton, CT.

Newenglandbowthruster.com

Isn't that in your back yard, Ulf?

[Dieselram94]

A little update...I didn’t get it glassed in the other night as I had hoped. But I did get it bedded in 5200. Two big setbacks happened. First one being I had to majorly modify the pipehead fitting as it was way too tall to fit with the rudder installed. So I cut it shorter as well as drilled out the inside below the bushing to allow the rudder to fit in deeper. This allowed just barely enough room for it to fit. Second big hold up came with me coming down sick (not corona). So I’m still not feeling well but excited to get this thing glassed in just as soon as I can!

[Dieselram94]

Also picked up a 2007 Honda 9.9 outboard with remote controls and electric start for secondary propulsion. Too good a deal to pass up!

[tribologist]

Actually, it's not RI... it's Groton, CT.

Newenglandbowthruster.com

Isn't that in your back yard, Ulf?

Sure is, In my extended backyard... we launch from there. The only thing it does not pay to do yourself is swapiing tires and do front wheel alignment... add ironing shirts and fertilize lawn.. the later due to potential EH&S risk.

If you now could get that boat in the water so we can figure how well it works..,

[tribologist]

I do not understand the chemistry of it, but it is a common procedure recommended by fine boat and airplane designers. To prevent oxidation and contamination, I guess. I always used just paper at hand and what worked. Decent dry paper should be ok. You really do not need to expose it for too long. Most wet paper I see, is kind of too fine.

We do the same at work when bonding aluminum if we dont have time to properly bond prep. Works very well. The idea is to simply fully wet the metal with the epoxy. Its very hard to truly clean. In this case it does not matter at all since you don’t need peel strength. You actually don't need any significant adhesive strength in this application. Its all mechanically held in place.

[Dieselram94]

Ok, finally it’s all done! Just waiting for this to set up now. I hope I got a good mechanical bond. I really tried to work the cloth into the grooves and work the air out. I guess time will tell!

[Dieselram94]

One final picture as I just painted this part of the bilge. Now onto keel repair!

[nebulatech]

Looks nice and clean, with heavier build where the shaft meets the hull. Great job!

Chemical bond is not possible to the stainless. Chemical bonding refers to the resins in individual layers cross linking chemically to each other, which only happens when wet is applied to wet. Any other bonding (resin to substrate, wet resin applied to a dry layer like the hull) relies on a mechanical bond, which is why sanding is so important.

Keel repair sounds fun. I have a bit of hull repairs to do myself. Just remember, if you use epoxy, you aren't supposed to put polyester on top of it, which includes polyester primers.

[Dieselram94]

Thanks! Yes, unfortunately the keel is cracked in the area that holds the skeg in place. It’s not really loose but I’m afraid it will lead to further damage if I don’t address it. I’ll start a new thread for that repair in a day or so as time allows me to get started on it.

[tribologist]

Thank you for the awesome ideas and discussion!!!
I had a hour tonight so I went ahead and removed the rudder port. It’s stainless steel and has grooves already in it! Just none that prevent it from spinning once the bond breaks free, also no evidence of any type of sealant on the flange where it meets the hull. No wonder it was leaking lol.

So... I’m thinking at this point reinstall as the factory did, only this time I will cut some vertical grooves to help it “key” into the new layup. That should prevent it from spinning if the bond lets go in the future. Also bedding it in a generous bed of 5200 as I don’t foresee removing this again. At least that’s my plan lol. I’m thinking of using the west system gflex epoxy as it’s flexible, and advertised as superior bond to stainless...for what that’s worth.
Although I really like the fiberglass tube idea!
Here are some pictures from tonight.

Is there one or two bushings in the tube?

[Dieselram94]

Two bushings, a upper and a lower bushing and a holder for the oring