Short shaft built better.....maybe....

[FNG]

Alright I'm hooked an I'm building my own mud motor. Short shaft. I have scoured the search feature so please don't blast me;

I'm going 18hp, belt driven short shaft. Built from scratch because I have a few ideas (I know....always someone trying to reinvent the wheel) The problems I'm faces are simple ones on the geometry I need to match. Shaft length to transom hight is everything on a long tail as I understand it. Building a short shaft, I can make my belt housing whatever height I need so I'm not sweating that.
My main questions being 1) is there a standard shaft length for a short shaft motor and 2) when I make my swivel/transome bracket, how much; if any, downward angle on the prop shaft do I need to allow for?

[Orphanedcowboy]

Go over to Mud Motor Talk and research, there are quite a few home brewed surface drives posted up.

You need trim up and down and a simple piece of all thread with a nut on the motor end and a handle for on the fly adjustments on the other will allow you to get it dialed in for various loads.

Google Copperhead and look at the pictures, you will see how they solved the trim adjustment issue.

Good luck and post tons of pictures please.

Sent from my SM-G950U using Tapatalk

[FNG]

Thank you an I absolutely will post a lot. The trim is one of the areas where I have a mad scientist idea. Lol