Arneson's, They break too......

[Pete B]

.041 would be about the right size, for this application. and to do it right, a pair of Safety Wire Pliers would help. Although loctite is good on certain applications, this type of locking is prefered in the Aviation industry.

[Bobcat]

Ugh, wired a sh*tload of F-4E parts together! I guess that the wire would only have to last one race ( as opposed to a pleasure boat's season)

[Pete B]

A ton of stuff gets S/W ed, and lasts until it is cut! Besides S/W, I am really surprised at the lack of inspections conducted on Steering components, tie bars , Etc. this stuff should be NDI'ed once a year, between saltwater, and the abuse it see's.it would be a small piece of insurance in my opinion.

[Cookee]

Rotational or torque force couldn't be responsible as most all propeller thrust in an Arneson gets transferred to the transmission/engine.

Only if the transom has broken!

[Ratickle]

Looking at the pics will the broken arnson let water in like a broken brovo or #6.

Rik or Cookee, there is no way for water to enter the boat if this ever happens again, is there?????


I don't want to answer for sure, since I'm not positive....

[Cookee]

Rik or Cookee, there is no way for water to enter the boat if this ever happens again, is there?????


I don't want to answer for sure, since I'm not positive....

With our drives (older 1721's) we have seals top and bottom so there would be no problem unless you ripped it all out of the transom - even with later version that use a chain on one side and gears the other you have to keep the oil in the right place which would keep the water out of the boat, there is no way I can see you would sink a boat from breaking an Arneson - Rik will hopefully confirm all of that ............ Don't worry!

[C35]

I am really surprised at the lack of inspections conducted on Steering components, tie bars , Etc. this stuff should be NDI'ed once a year, between saltwater, and the abuse it see's.it would be a small piece of insurance in my opinion.

You would think. You'd also think people would take all sorts of steps to avoid bad things from happening, like strong canopies and full time air systems. The race orgs aren't going to lose a single reg fee from a race team over something like this. And if the boat owner yourself doesn't find it their your best interests to look after themselves...

[Ratickle]

I would have to believe the owners of the boats do the inspections to the best of their capabilities. There is no way, my opinion, they would want to spend the kind of money it takes to enter and run a race like the worlds, and take any chances on components.


Maybe I'm wrong.....

[Anchored]

Unless I'm missing something, it seems like this is newsworthy precisely because it happens so rarely. It seems that it could only have been lateral forces or shear forces that broke it in that way. Rotational or torque force couldn't be responsible as most all propeller thrust in an Arneson gets transferred to the transmission/engine. I may be negating the effects of prop lift on the unit. What does the race crew have to say about it?

You're all mixed up. the forward thrust is transferred from the thrust tube to the gear case then extension box then transom.
The failure is from direct lateral load on the drive. No thrust is transferred to the Velvet drive or engine.

Jeff

[Rik]

You're all mixed up. the forward thrust is transferred from the thrust tube to the gear case then extension box then transom.
The failure is from direct lateral load on the drive. No thrust is transferred to the Velvet drive or engine.

Jeff

Correct other than the failure analysis. The piston on the trim cylinder shaft came off allowing the drive to fall. When it fell the ball extended beyond the range of the socket breaking the socket. Then the thrust tube was free from the socket housing. This had nothing to do with lateral loads, thrust loads or any loads other than gravity.

[old377guy]

I stand corrected. Some days I just don't put on my thinking cap....

[Anchored]

Correct other than the failure analysis. The piston on the trim cylinder shaft came off allowing the drive to fall. When it fell the ball extended beyond the range of the socket breaking the socket. Then the thrust tube was free from the socket housing. This had nothing to do with lateral loads, thrust loads or any loads other than gravity.

It's reassuring to know the ball socket nut it tough as nails!

Jeff

[Ratickle]

Yep, Arneson's are sweet.

I had never seen one break like that one did, so I figured it would be fun to give Rik a bad time......

Curious Rik, when something like this happens, do you do an email type notification to all your customers as an update for a possible enhancement? Or, was this such a fluke that you never expect others to experience the same issue?

[Rik]

Yep, Arneson's are sweet.

I had never seen one break like that one did, so I figured it would be fun to give Rik a bad time......

Curious Rik, when something like this happens, do you do an email type notification to all your customers as an update for a possible enhancement? Or, was this such a fluke that you never expect others to experience the same issue?

I am looking into it, but I am also trying to learn the background of these drives. They have been apart I was told so how much and who performed modifications?? As for a cure, sure as others have pointed out a safety wire or similar method can prevent future concerns. Thankfully this is not a prevalent problem rather an isolated one so concerns have to be exercised accordingly.

[Ratickle]

Thanks Rik, appreciate it......

[old377guy]

Well then, that's a wrap. Always good to get the story and learn something. BTW Rik, I would like to come by your shop next time I'm visiting our friends in San Rafael.