How much thrust and what shaft lenght should I use?

[Big Unit]

Re: How much thrust and what shaft lenght should I use?

It's a fiber glass hul and I already figured out where and how I will place the bracket that will hold trolling motor. Mechanical engineering is my full time job so this part of the story is not a problem. I designed the bracket and I'm waiting the trolling motor to send the drawings to the company that will do the job. It will be made of a 3/8'' 3003 aluminum will 4 legs. each legs wil have a tab that will fit the shape of the boat. The top part of this bracket will be parallel to the ground. Maybe I could upload a picture of it if you want to see what it looks like.

This explanation brings me another question. I will have to put some rubber spacers under my brackets legs. What kind of screw should I use knowing that it will fasten through the hull?

Thanks.

 

[John_S]

Re: How much thrust and what shaft lenght should I use?

Sounds like you have the mounting thought out, just be flexible with the shims because like the water line, boat level position won't be known until place in water. While you don't need perfect level, the closer, the better, especially if you are getting any autopilot option.

There are specific rubber isolated T-nut for mounting trolling motors, like these: http://www.iboats.com/Motorguide-Mo...44281752--**********.288180133--view_id.39218

 

[Silvertip]

Re: How much thrust and what shaft lenght should I use?

You are making this project way more difficult than you need to. Minnkota and others make a trolling motor installation kit that consists of rubber well nuts and all the stainless hardware needed. A hardware store, Lowes, Home Depot etc can provide any number of rubber/neoprene washers you need to use as spacers. Absolutely no need to design any special bracketry. In fact using well nuts you don't even need to reach beneath the deck and provides isolation from noise and vibration that would result from any other connection method.

 

[Big Unit]

Re: How much thrust and what shaft lenght should I use?

My boat is a bowrider and all the contours are ''rounds'' and there is the red/green light in front. There is no ''flat'' part where I can fit standard brackets. If I could, I would believe me. Thats why I need to design a bracket.