Nut size for prop?

1 month into enjoying the new Gori propeller it has fallen off the boat Cry

not sure how this could have happened? everything installed per the instructions Cry

any how looking at maybe having the old one welded but I'll need a castle nut at least, any one know of a reasonable replacement or the size? I'm going to draft a note to PYacht and see what they have to say...........ugh!

Jon

Pandora

Hull#167

Lake Ontario SBYC
Past President LYRA

I am really sorry to hear that you lost your new prop. Terrible! I think the most likely way for that to happen is from not getting the ends of the cotter pins bent down into the correct position such that the operation of the prop's blades don't interfere with them and cause them to break off..

I very strongly recommend AGAINST welding the prop's spindle hub to the main body. Even if you only operate if fresh water, eventually you will damage the sail drive casing with electrolysis. We have now received three fresh water Lasers in Vancouver, and I have had to re build each of these sail drives owing to exactly such treatment to the propellor.

What I have been doing is to heat and then punch the center splined hub out of the main body. I have in one instance made a new one of these, oversized its center, then deformed it with a milling machine so that it was not round. To the main body, I bored out the center to 30 mm, then went in with a long 10mm end mill and also deformed the bore sort of into a square shape. The two were then aligned and the center splined hub cast in place with flexible polyurethane of 80 durameter.

The alternative and more simple method is to heat the body and hub,then press the center our with a strong press. Clean the bores up. The have a welder braze some brass or bronze rods to the sides of the center splined hub so that it is not round. Someone must then bore out the main prop hub and deform it so that it is not perfectly round (any amount of deformity will do, and cast the center back in place. Such urethanes are produced by Smooth-On, cost about $40 a pack, and one only needs to mix up about 3 ozs. to fill the hub. I doubt they really take more than 2 oz.

I could do this all for you, but it is a bit of a labour of love and takes quite a few hours, but I am getting better at it. On certainly could not make any money on this over purchasing a new prop, however I would be happy to do it in my capacity of an owner and hobbiest for. One would still have to suffer the costs of shipping both ways, etc. If I were still effectively working, surely it would be better to do some overtime at the office and buy a new prop! Send me a personal message if you want help with this and we can work something out.

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Jon167 Members Profile Send Private Message Find Members Posts Add to Buddy List Skipper Joined: 14 April 2011 Location: Webster NY Status: Offline Points: 95	Post Options Post Reply Quote Jon167 Report Post Thanks(0) Quote Reply Topic: Nut size for prop? Posted: 15 July 2012 at 9:39pm
	1 month into enjoying the new Gori propeller it has fallen off the boat not sure how this could have happened? everything installed per the instructions any how looking at maybe having the old one welded but I'll need a castle nut at least, any one know of a reasonable replacement or the size? I'm going to draft a note to PYacht and see what they have to say...........ugh!
	Jon Pandora Hull#167 Lake Ontario SBYC Past President LYRA

bal149 Members Profile Send Private Message Find Members Posts Add to Buddy List Skipper Joined: 14 August 2010 Location: canada Status: Offline Points: 67	Post Options Post Reply Quote bal149 Report Post Thanks(0) Quote Reply Posted: 20 July 2012 at 7:49pm
	the previous owner of Balaou lost the prop because it was installed back to front

frfletch Members Profile Send Private Message Find Members Posts Add to Buddy List Commodore Joined: 13 May 2008 Location: Canada Status: Offline Points: 365	Post Options Post Reply Quote frfletch Report Post Thanks(0) Quote Reply Posted: 21 July 2012 at 10:38am
	I am really sorry to hear that you lost your new prop. Terrible! I think the most likely way for that to happen is from not getting the ends of the cotter pins bent down into the correct position such that the operation of the prop's blades don't interfere with them and cause them to break off.. I very strongly recommend AGAINST welding the prop's spindle hub to the main body. Even if you only operate if fresh water, eventually you will damage the sail drive casing with electrolysis. We have now received three fresh water Lasers in Vancouver, and I have had to re build each of these sail drives owing to exactly such treatment to the propellor. What I have been doing is to heat and then punch the center splined hub out of the main body. I have in one instance made a new one of these, oversized its center, then deformed it with a milling machine so that it was not round. To the main body, I bored out the center to 30 mm, then went in with a long 10mm end mill and also deformed the bore sort of into a square shape. The two were then aligned and the center splined hub cast in place with flexible polyurethane of 80 durameter. The alternative and more simple method is to heat the body and hub,then press the center our with a strong press. Clean the bores up. The have a welder braze some brass or bronze rods to the sides of the center splined hub so that it is not round. Someone must then bore out the main prop hub and deform it so that it is not perfectly round (any amount of deformity will do, and cast the center back in place. Such urethanes are produced by Smooth-On, cost about $40 a pack, and one only needs to mix up about 3 ozs. to fill the hub. I doubt they really take more than 2 oz. I could do this all for you, but it is a bit of a labour of love and takes quite a few hours, but I am getting better at it. On certainly could not make any money on this over purchasing a new prop, however I would be happy to do it in my capacity of an owner and hobbiest for. One would still have to suffer the costs of shipping both ways, etc. If I were still effectively working, surely it would be better to do some overtime at the office and buy a new prop! Send me a personal message if you want help with this and we can work something out.