Rudder construction question

I have an Epic 9" surf rudder foil. It is one of the older models that had the CF shaft and of course it snapped. I am in the process of fitting a stainless steel shaft but have hit a snag (actually hitting a snag was what broke it in the first place.
There appears to be an aluminium plate sandwhiched down the centre of the foil. I set it up in the drill press but the drill is hitting the metal and running off centre. I have an end mill so i can get a straight hole going but was wondering if any of you good folk might know how deep this metal plate runs?
I want to fix the SS shaft as far into the body of the foil as possible because I'm not that keen on ocean paddling without a rudder. great for core conditioning but overall a real nuisance.
Cheers

I have drilled out and repaired a few carbon shafted epic rudders after they had come to grief.

Yes they snapped on impact with rocks etc. but saved the back of the boat being totalled.

The metal plate is only thin, however on all the ones I have repaired for myself and other people there has been a second plate further down so you have 2 to drill through.

I had the same problem with the drill running off centre but got away with going back to a small pilot drill to get through the plate then working back up in size.

Once I had epoxied a new stainless shaft in a drilled 2 small holes right through the side of the rudder and new shaft an put 2 stainless pins through (similar to size to the pin at the top of the shaft. This is for added insurance against the shaft twisting in the rudder under force.

I then filled the ends of the small holes over the slightly sunken pins so that they cant be seen.

I have paddled with a rudder repaired like this for over 12 months with no issues.

Hope this helps.

Thanks for reply. Was planning on pinning the shaft as well. I've already messed up the top plate so will get back on track with the end mill but that's handy info regarding the second plate.
I'm actually making the rudder for my Stellar hoping to improve it's surfing ability.
Cheers

Epic is a very fat shaft and stellar thinner from memory ? You may be better off simply getting a new blade moulded onto your stellar shaft . The inside of epic rudder blades I have seen had 3 pins through the shaft to stop the shaft pulling out or twisting inside the blade. (and the black composite shaft{i saw} is glass not carbon by the way)

Yep. The Epic shaft is fatter than the stellars. Was lucky enough to find a piece of high grade Stainless Steel of the correct dia.
I have a spare Epic rudder yoke which makes the process so mush easier as well. Don't have to worry about machining a square drive on the end.
This is essentially a low cost trialbecause I have the parts. However, if it works but my workmanship fails then I will probably look into your suggestion of having one professionally fitted to the existing shaft. Being in the industry yourself, what sort of cost would a punter be looking at for a such a job??
Cheers

You could always shape up some plywood of the same thickness as the shaft,and lay it on a flat surface and pour some resin around the shaft so its level with the rest of the blade, After that has cured use the timber plys as a contour map and foil each side, and then lay some glass over each side for strength ,if you have access to vacuum you can do both sides at once. If your blades front edge is quite round you could just wrap the fabric all the way around.

otherwise about $80 for one to get made in our mould

$80 sounds like a resonable price. Especially for the DIY challenged.
Wood is another option. Have had this in my favourites for awhile now
www.instructables.com/id/Homemade-rudder...p5/Fishished-rudder/

I wrote a reply before but somehow lost it

that rudder in the link looks very light with a balsa core and very little glass but i prefer mine a lot sturdier.
It would shed weed well with that layback and the little deflector glued on the hull . Cheers Lats

flat water use I guess.