Rudder inspection

[a64pilot]

My IP38 is on the hard getting a bottom job and other work, rudder is being removed.
Exactly what should I inspect beyond the obvious, dye penetrate the stock?
Assuming I can find out what it weighs, I can weigh it to see if it has water in it?

[neilpride]

Visible cracks , moisture meter, most rudders readings are hig , if yes, drill a pilot hole at the bottom , and the usual stock inspection for corrosión or cracks, with the Wheel stuck, try to push hard the rudder sideways , any obvious play call for a rudder rebuilt...
Cheers.

[a64pilot]

I had a BIG boy pushing real hard on the rudder during the survey, about 300 lbs worth. And I did this time too when the boat was pulled. Due to it's age (27 yrs) corrosion and wasting of the internal structure is a very real possibility.
So just a visual with maybe a 10X magnifying glass for the stock, no Dye pen?

[robert sailor]

Tell you what I did with several boats. I carefully drilled some holes in the lower section and took a peak inside. If it is wet and most are then I drained the water out and let them dry. I then drilled a larger hole just thru the skin so that I could see the stock and internal supports, have a peak at welds and check for cracks. If all is well after it is dry I make the repairs, fair it and if it is built in halves and glued together then I wrapped it with cloth and faired it out and done deal. If it was really soupy after I did my first checks I made a template of the rudder. Then after removing any loose and soaked foam I drilled larger holes starting from the bottom and filled it with resin. After it went off I moved up drilled more holes and filled it with resin until I got to the top. Wrapped it with cloth and used the template when I was fairing to ensure I had the original shape.

[neilpride]

Originally Posted by a64pilot

I had a BIG boy pushing real hard on the rudder during the survey, about 300 lbs worth. And I did this time too when the boat was pulled. Due to it's age (27 yrs) corrosion and wasting of the internal structure is a very real possibility.
So just a visual with maybe a 10X magnifying glass for the stock, no Dye pen?

The most likely suspicious área is where the stock penétrate inside the rudder, clean the ss really well, i use emery cloth, and yes 10x mag glass and Dye Pen can do the trick, if you feel worry use a dreamel and dig a chanel around the fiberglass where the stock enter inside the rudder, if is clean , good news, if is rusted or with severe pitting, bad news...you can fill it later with some epoxy...

[a64pilot]

Thanks guys, I'll start fist by seeing how much water is in it. I'd assume if it's full, best to split it in two, dig out the foam, do whatever is necessary for the internals and put it back together and fill with resin with microballons?
First I'll see how much water it holds, then go from there

[UNCIVILIZED]

I've just started doing some self "home schooling" on Non-Destructive Testing (NDT), & some of the ideas might be helpful in terms of checking out your rudder. Most of them are mentioned in my posts in this http://www.cruisersforum.com/forums/...ml#post1701631 thread. And there are a variety of them. Plus someone on another forum sent me some more links on NDT which I've yet to look at/into. If you want'em, LMK. But definitely read the posts in that other thread.

In addition to that, there are a couple of obvious ones; have the thing X-ray'ed so that you can see what's going on with the structural bits inside. And or, send it to Island Packet for a checkup, or have them send out a rep or recommend someone local to give it a serious going over. Given that they built the thing, they'll know loads about it.

Also, if you're going to remove some of the glass surrounding the shaft, where it enters the rudder, if it were me, I'd do some studying on flexible epoxies. So that when you refill the area which you removed, the material which you're putting back in has more built in "stretch" to compensate for different material expansion rates & coefficients. Thus it'll be more likely to remain waterproof. And of course, do the proper prep for bonding to metal when you rebuild things.

[a64pilot]

I think IP buys the rudder I think, Foss foam comes to mind, but not sure.

Years ago I was a Level 3 NDT tech for a short while, but no more as recency of experience requirements for even level 2 is quite high, but I still know how and still Have Dye Penetrant chemicals and the UV light. Eddy current would I think be best, but I don't have that equipment.

Coin tap test didn't seem to indicate it was full of water, but I guess the acid test is to drill a hole, of if it takes a fork lift to pick it up

[robert sailor]

Originally Posted by a64pilot

I think IP buys the rudder I think, Foss foam comes to mind, but not sure.

Years ago I was a Level 3 NDT tech for a short while, but no more as recency of experience requirements for even level 2 is quite high, but I still know how and still Have Dye Penetrant chemicals and the UV light. Eddy current would I think be best, but I don't have that equipment.

Coin tap test didn't seem to indicate it was full of water, but I guess the acid test is to drill a hole, of if it takes a fork lift to pick it up

My bet is that it will be in better shape then you think.

[a64pilot]

Originally Posted by robert sailor

My bet is that it will be in better shape then you think.

I hope so, but 27 yrs, is a long time. I should know in a week or two.
Just seems prudent to pull, and if it's out. I want to know everything to check, seems straight forward, common sense stuff.

[minaret]

Originally Posted by a64pilot

I hope so, but 27 yrs, is a long time. I should know in a week or two.
Just seems prudent to pull, and if it's out. I want to know everything to check, seems straight forward, common sense stuff.

Drill your first test holes from the bottom right in the center seam before pulling the rudder off the boat. If it drips, I'd recommend you go ahead and open up a window in one side so you can reef out the foam and do a proper inspection. Good call to inspect, and plan for the worst. I'd say more than half of the rudders of this vintage I inspect should probably have some degree of rebuild. Just catch it before the armature goes bad and you will save $ in the long term.

[Cheechako]

Originally Posted by minaret

Drill your first test holes from the bottom right in the center seam before pulling the rudder off the boat. If it drips, I'd recommend you go ahead and open up a window in one side so you can reef out the foam and do a proper inspection. Good call to inspect, and plan for the worst. I'd say more than half of the rudders of this vintage I inspect should probably have some degree of rebuild. Just catch it before the armature goes bad and you will save $ in the long term.

Yep... drill a hole. I'd inspect the stock right where it exits the rudder real well. Not sure you can see much though. If the rudder has water in it then it likely creeps down past the stock exit point... which means the problem area would likely be inside the rudder at the top. (low oxygen environment)