Rudder lost + storm video on Mainship 390

Hi guys! I'm the owner of 2002 mainship 390 trawler twin engine and I live in Russia Moscow. Last summer we've lost a right rudder. Here are the pictures how it looks now:

Yandex
Yandex

Could you suggest where to buy new one? Estimately what will be the price?

If it will be interesting to you here is our video during the storm on the russian lake:
Thank you!

Welcome aboard! I see you made it over here from the Yahoo site. This site has lots of people knowledgeable in trawler systems and I am sure you will find help in replacing your rudder. I will give you my thoughts:

First, like I said on Yahoo, Mainship is no longer in business, they went bankrupt a few years ago and the company that bought them, Marlow Yachts does not support the older Mainship boats with parts.

But there are a couple of ways to get a new one. Maybe the easiest is to buy a standard rudder from a company like Buck Algonquin who makes rudders and shafts and also makes bearing and packing assemblies. Look here for a series of rudders that might work for your boat: Bronze Special Rudders On Buck Algonquin.

They don't look like exact replacements for your rudder, but if the overall dimensions are ok, one of these should work. And it is entirely possible that Buck Algonquin made your rudder for Mainship to their design and maybe BA could build one for you. BA is the only supplier I know about for bronze rudders, but maybe someone else on this forum knows of others.


If you click on the small box on the right of the forgoing BA page, it gives rudder reference diagrams for their rudders and on the lower right of that page it talks about custom castings to your spec. They might still have the old Mainship molds if they made your rudder.

The stub on your broken rudder looks very small, an inch or less in diameter. The 22" long blade on BA's web page has a 1-3/4" shaft diameter for example and their smallest which has a blade length of only 14" has a shaft diameter of 1", but that one looks much too small for your boat.

BA's rudders are cast bronze which is the best material for this sort of rudder.

Another way is to get a local fabricator to make one for you. There are two possible ways:

One is to make one out of bronze plate, but finding the right material will be tough. Your fabricator will have to grind the leading edge round and taper the trailing edge. Then cut a slot for the rudder shaft and braze or maybe use a bronze shaft and weld it in place.

The other way is to make it out of fiberglass. Sailboats use these all of the time, but the smaller and higher stressed power boat props are usually bronze. You will have to start with a stainless steel shaft, weld up an "armature" to it to distribute the loads horizontally, then encase it in structural foam and fiberglass the sides.

All in all, I would buy a standard Buck Algonquin rudder even if it wasn't exactly the same shape.

Good luck, others will have more ideas for you.

David

ways:
One is to make one out of bronze plate, but finding the right material will be tough. Your fabricator will have to grind the leading edge round and taper the trailing edge. Then cut a slot for the rudder shaft and braze or maybe use a bronze shaft and weld it in place.

Click to expand...

A better way (or at least another way) to manufacture a rudder is to have one cast out of bronze. Use the rudder you still have as the pattern for the mold.
Then just a little machining to get the surfaces good and you're done. It should be easy to find a casting shop.

jleonard said:

A better way (or at least another way) to manufacture a rudder is to have one cast out of bronze. Use the rudder you still have as the pattern for the mold.
Then just a little machining to get the surfaces good and you're done. It should be easy to find a casting shop.

Click to expand...

That would be my suggestion.

jleonard said:

A better way (or at least another way) to manufacture a rudder is to have one cast out of bronze. Use the rudder you still have as the pattern for the mold.
Then just a little machining to get the surfaces good and you're done. It should be easy to find a casting shop.

Click to expand...

+1

I've had many complex custom bronze pieces cast. Right now in Toronto it costs about $6/lb. so a 20lb. rudder would cost about $120 + another $100 for machining. I'm almost positive the Mainship rudders, like their propellers are manganese bronze which is much easier to machine than silicon bronze.

Marine Hardware supplied a lot of those type parts to Mainship:

Welcome to Marine Hardware


Oh, and what storm??

Fresh breeze on a lake.

I'm not much help on your rudder question, but thanks for posting that video. We have a Mainship 37, not a trawler, but your video made me smile. We run ours the same way in rough weather -- from the upper helm, all the windows closed except the forward panel so we can see clearly. Makes for a chilly passage, but it builds character. Helps build personal endurance. Lots of people might criticize the previous generation Mainships as mostly coastal/recreational boats, trawlers or aft cabins, I sure have been impressed with how they handle rough weather.

(Our model doesn't actually have a lower helm, but even if it did, I'd still run it the way you do in rough weather. We had a lower helm on our prior boat, never used it, ever.)

Greetings,
Welcome aboard.

Welcome to TF, and thanks for posting that video. We also run on plane in storms like that but we do close all the front windows. I don't mind a bit of water in the summer but in the winter I'd much rather be dry.