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screws on rudder system ( hull fitted) fail quite often.
http://www.hobie.com/forums/viewtopic.php?f=75&t=49582		 Page 2 of 3
Author:  mmiller [ Wed Oct 16, 2013 8:42 am ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
This has been in place since about March of 2011. There was no bulletin on a running change / improvement.

80390346 SCREW W/NUT ISLAND GUDGEON

This is the 1/4-20 thread PH17-4 stainless stud with a seized-nut for a head.
Author:  Tom Kirkman [ Wed Oct 16, 2013 9:43 am ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
I pulled the gudgeon off my TI just a bit ago because after looking inside I could see where there were protrusions for 3 molded in nuts. Somehow I didn't recall that third one being there when I originally reshaped the gudgeon. Sure enough, the hull does indeed contain 3 molded in nuts, while the gudgeon is only fitted for two.

Image

I've not had any problems, whatsoever, even though I replaced the Hobie studs/nuts with standard 1/4-20 SS screws. I think this is because by reshaping the gudgeon to match the hull stern shape, a great deal of pressure and resulting fatigue has been taken off the screws.

Image

Since I do have the capability for a 3rd screw, I'll likely order the newer gudgeon and have what I think will be an almost bullet proof set up. However, I'll still reshape the new gudgeon to match the stern just as I did the original one. I really believe that's the key to getting the most strength and durability out of the assembly. If you're putting out to sea or any heavy water, I'd darn sure make this modification.
Author:  stringy [ Wed Oct 16, 2013 1:45 pm ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
mmiller wrote:
This has been in place since about March of 2011. There was no bulletin on a running change / improvement.

80390346 SCREW W/NUT ISLAND GUDGEON

This is the 1/4-20 thread PH17-4 stainless stud with a seized-nut for a head.


Thanks for that Matt.
Since 3/11?? I'm a bit surprised that this wasn't made known earlier as there have been a number of failures reported on this forum.

Tom Kirkman wrote:
I've not had any problems, whatsoever, even though I replaced the Hobie studs/nuts with standard 1/4-20 SS screws. I think this is because by reshaping the gudgeon to match the hull stern shape, a great deal of pressure and resulting fatigue has been taken off the screws.
... However, I'll still reshape the new gudgeon to match the stern just as I did the original one. I really believe that's the key to getting the most strength and durability out of the assembly. If you're putting out to sea or any heavy water, I'd darn sure make this modification.


You have a good point there Tom and I hope Hobie are listening.
Author:  mmiller [ Wed Oct 16, 2013 2:53 pm ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
stringy wrote:
mmiller wrote:
This has been in place since about March of 2011. There was no bulletin on a running change / improvement.

80390346 SCREW W/NUT ISLAND GUDGEON

This is the 1/4-20 thread PH17-4 stainless stud with a seized-nut for a head.


Thanks for that Matt.
Since 3/11?? I'm a bit surprised that this wasn't made known earlier as there have been a number of failures reported on this forum.



This was my first reference to the PH17-4 screws that I could find... back in October 2011...

mmiller wrote:
Quote:
More details please.
Upgraded part #'s? Available down under yet?


Not yet available. This is really new information. As a precaution, we are trying to source new screws made from the same material as the V brace screw (17-4 I believe). These are not off-the-shelf parts. They would be custom. Currently we are making custom bolts with a V brace screw and a nut jammed on as a head.

Just be sure your screws are tight. I think a loose screw may be the cause of failures. Especially after watching this users video.


Seems the factory engineers requested it in March, so may have taken a little while and then replacement parts were not defined by October of 2011.

Also... Correct number is 8030346 SCREW W/NUT ISLAND GUDGEON
STUD 1/4-20 x 1" PH17-4 W/ NUT SEIZED ... fat fingers.

Looks like we got the parts into the parts department in December 2011.
Author:  stringy [ Wed Oct 16, 2013 8:48 pm ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
Thanks again for those details Matt. I'd forgotten all about this issue (and that I'd asked the same questions back in '11!)
I have regularly checked the tightness of the bolts and have never had a problem but I have ordered the stronger bolts.
I think Tom makes a very good point in that an ill fitting gudgeon could also be a contributing factor in these failures.
Author:  Herbaldew [ Thu Oct 17, 2013 9:57 am ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
Here is a picture snjsanders posted on Sep 13, 2012 - my gudgeon looks exactly like this:

Image

I would like to do some sanding for a better fit and replace the studs but I'd like to clarify a couple things, first ... "8030346 SCREW W/NUT ISLAND GUDGEON STUD 1/4-20 x 1" PH17-4 W/ NUT SEIZED" ... The upper and lower studs are the same so I need two of this part number to replace them? This part is stronger than the studs that came on the boat (2011 TI)?

Secondly, I found this in an old post:
bosab wrote:
If you ask nice at Hobie they will give you or sell you a new guedoen that is much better made for the TI and new rudder system. it fits better and compensates for the bit of bulge at the mounting points. it is not the compromise design they had for the old twist and stow rudder.


Is this correct? Should I also order a new gudgeon? I think I remember my dealer saying that he upgraded the rudder from the T&S.
Author:  mmiller [ Thu Oct 17, 2013 3:31 pm ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
Your transom appears to only have the earlier 2 hole insert.

You can/should replace the lower screw with the stronger seized nut PH17-4 part #8030346 for best strength.
Author:  mmiller [ Thu Oct 17, 2013 4:26 pm ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
I compiled a history as best as possible. This shows possible configurations starting from early boats to current.

- Original Twist and Stow rudders. 2 hole gudgeon with 2x 8030214 SCREW 1/4-20 x 1" BTN HD (may have had phillips heads now has allen)

- Retrofitted rudders - same fasteners

- Changed insert to add 3rd leg (visible 3rd hole) to add strength to transom. More plastic and 3rd leg creates more resistance to pulling out or pushing in.

- Updated lower screw to PH17-4 higher strength stainless. Production fasteners are not available in PH17-4, so we constructed of a stud and seized hex nut for a head (slotted end on stud) Upper 8030214 SCREW 1/4-20 x 1" BTN HD / Lower 8030346 SCREW W/NUT ISLAND GUDGEON STUD 1/4-20 x 1" PH17-4 W/ NUT SEIZED

- Decision was made to replace the PH17-4 assembled part and go to a larger diameter (and commercially available) 5/16-24 screw and use both upper holes with 1/4-20s. Late March 2012 started 3 hole gudgeons with 1x 8030355 SCREW 5/16-24 x 3/4 BTN HD SCK Lower and 2x 8030214 SCREW 1/4-20 x 1" BTN HD Uppers.

- AI hulls started coming with the same 3 hole gudgeon and fasteners earlier this month.
Author:  tonystott [ Thu Oct 17, 2013 5:03 pm ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
Matt, forgive my slowness of uptake, but I am confused.

I bought my 2012 model T! in June 2012. Am I correct in understanding that Hobie at some time has changed the sockets molded into the transom from two 1/4-20 threaded holes, to " Late March 2012 started 3 hole gudgeons with 1x SCREW 5/16-24 x 3/4 BTN HD SCK Lower and 2x 8030214 SCREW 1/4-20 x 1" BTN HD Uppers."

So what fixings would I need along with the new gudgeon #88991094 which I assume now comes with three holes?
Author:  Tom Kirkman [ Thu Oct 17, 2013 5:22 pm ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
All three threaded inserts on mine require a 1/4-20 screw. If the bottom bore in the new gudgeon is larger I'll just sleeve it to accommodate the same 1/4-20.

I recognize that such running changes can sometimes be a bit fuzzy until all the various parts and pieces get sorted and standardized.
Author:  mmiller [ Mon Oct 21, 2013 8:01 am ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
If you have the larger lower screw… no changes needed.

If you have 3 available holes in transom and a two hole gudgeon… you can add another 8030214 SCREW 1/4-20 x 1" BTN HD (requires purchase of three hole gudgeon)

If you have a pan head ¼-20 lower… you can change to the 8030346 SCREW W/NUT ISLAND GUDGEON STUD 1/4-20 x 1" PH17-4 W/ NUT SEIZED
Author:  NOHUHU [ Mon Oct 21, 2013 12:59 pm ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
AI owners are not effected? They either have the complete 3 hole components or are not able to use them on their 2 holed hulls, correct?
Author:  mmiller [ Mon Oct 21, 2013 1:22 pm ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
The same screw information should fit AI issues as well. The AI was not considered to be at risk of screw failure like the TI due to smaller sails / loads, but the bottom PH 17-4 stud and using all three holes if available would be good for AI as well.
Author:  Tom Kirkman [ Fri Oct 25, 2013 9:22 am ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
Part #88991094 only has two screw holes. Just got one in from Austin Kayak expecting it to be the three hole model. It's not.

Anybody got the part number for the 3 hole gudgeon? Thanks.
Author:  mmiller [ Fri Oct 25, 2013 9:26 am ]
Post subject:  Re: screws on rudder system ( hull fitted) fail quite often.
Sorry for that. The gudgeon was a rolling change... same number. Specify 3 hole. I have reviewed our stock here to be sure all are 3 hole from now on. did that before, but...
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