After successfully removing two puzzlenuts with the shop-made key, the key failed on the third one. Sheared the rods right off. Mmm. Rods were made of 1/8 mild steel rod. Made new key from the previous drawing, using drillrod this time.
Then it started raining for several days. It finally stopped yesterday.
Weather ain't great, but it ain't raining and I no longer need a canoe or waders to go in the back yard, so time to remove the last puzzlenut.
Pull boat out of boat tent. Assemble tools. Tap new snug-fitting tool onto last puzzlenut with deadblow hammer until it goes bang rather than thud. I did say snug fit, right? OK, it's fully seated. Assemble socket, ratchet, and 24" cheater (old Rabbit front driveshaft), place on puzzlenut tool, mutter invocation to St. Erho, start applying steadily increasing pressure on yonder end of the cheater bar. The truck and trailer rolled backwards a bit. Leaned a bit harder.
SNAP! Snap? I didn't plan on snap, what's with the snap, I mused curiously. I muttered the ancient Celtic word for "curious" which has rather different connations in modern English......that's my story and I'm stickin' to it.
The welds between the hex part and the key had snapped. Mmmm. My welds failed. This does not happen in real life. Leprechauns named Murphy have been dancing in my back yard. Now I gotta get that muthuh off of there, hadn't planned on that.
Large visegrip, couple of sideways taps to rock it a bit, a little prying with large screwdriver, thoop! Came off without a fight. Snug fit, nyaahh! Drillrods within are pristine and laughing at me. Bring bits into shop, fit together, fire up the TIG and weld the snot out of it. All the way round this time, puhlenty of heat, used ER70S-6 filler this time. If it's good enough for airframe welding, it oughta be good enough for this job. Puddle the size of a 12D nailhead, probably at least as deep as its radius. Got me some penetration, and generous fillet build as well. Tossed it in the water bucket to maybe lightly heat-treat the drillrods within.
Go back out, tap tool onto puzzlenut until it goes bang rather than thud. Just 3 light taps this time. Assemble tools, start leaning on the yonder end of the cheater. Truck and trailer start rolling. Keep increasing the torque. Hello, the cheaterbar is still moving but the truck and trailer are no longer rolling! YESSS!!!!
A few strokes later, I'm looking at a bare stud, mercifully not a sheared off stud. Man, it hadda be close -- I've sheared off 3/4" bumper bolts with that kinda torque. Those studs must be some kinda robust steel. Smear a bit of anti-sieze on the stud, wind on new puzzlenut to about 60 lbf-ft of torque, replace hub cover, put new key in the captive mesh bag in the tacklebox locker, lock the hatch, back boat back into tent with big grin.
Gee, it only took me two or three weeks to get that nut off -- but I got 'er done as they say. Sure glad I decided to get that leaky tire fixed in my backyard rather than alongside a road somewhere.