Hi,
I am helping a friend who purchased my old (mid 80's) H16 and has an issue with the rudder gudgeon attachment and I need some knowledge to help her out.
I recently changed out the lower rudder gudgeon due cracking, some of the S/S attach screws were bent, they were very tight, I was reasonably confident they came out without causing secondary damage. New parts ordered and refitted all 4 screws were lubricated but still had some drag to screw in all the way, one screw started to strip when home so I stopped at that point, I guess that one is ~30% of its original integrity.
Her first sail in light conditions and that complete gudgeon pulled all 4 screws out, this baffles me, I have a solid enough mechanical background yet didn't pick anything odd bar the one starting to strip, the other 3 felt like they screwed home securely.
Unfortunately we don't have the old bent screws to compare for length, the new ones are ~ 1" in length and sold in a packet of 20 with the comment that they are a universal screws for the H16. However, I have a gut feeling the ones that came out were longer and I am wondering whether when refitting I was screwing through flock or some other medium in there giving feel of screwing into thread but never actually engaged the thread due shorter screws.
My questions are, what is on the inside of the transom, I assume some sort of glassed in backing plate with captured nylock S/S nuts or similar. How long are the correct screws? are the female threads open at the back end? can they be tapped successfully. I would rather not pull one of the other gudgeon screws to compare length, what ain't broke and sleeping dogs and all that.
Is there a known failure mode in here (saltwater use). To my thinking if they were the correct length then we have an issue that might mean cutting an access hole in the rear top deck, I can do this work and have done this sort of thing on composite aircraft.
If anyone has a photo of what's in there that would be brilliant, otherwise just a description will do.
Thanks in advance, Mick
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