Cleaning corrosion from fuselage interior

Thanks Warren!

Perfect timing on this message. I just got back from the hangar, finishing the job of removing almost everything aft of the yokes.

My A&P suggested Alumiprep which I purchased but haven't yet used. I'm glad to read that you agree! My tail cone & center section contain decades worth of fogging oil residue caked with grime so we've rendered it safe to pressure wash. I did try cleaning up the area around the control mast with a 3M Roloc Bristle Disc which works wonderfully. I'll be interested to see how many discs I eat through by the time I'm done.

The coupe has even more holes now because we're installing the center section & elevator inspection plates. Those should help with all this pressure washing, alumiprep, and priming.

Aircraft Spruce Bonderite C-1C 33 ARCO

Alumiprep 33 hit spots first with 320 wet / dry sandpaper to takeoff hit spots. Treat spots with the 33 let set for 4 or 5 mins. Rinse with water. the idea is to cut through the corrosion. It may leave a gray discoloration. You can do the frame-to-frame area. Then retreat spot that look to have remaining Corrosion. I then I use Scotch-Brite pads # 07447 to do the area wipe it with clean rag paint with self etching spray can.

Yet another question about refurbishing my coupe!

The previous owner had stored indoors and treated with ACF50, but somewhere in the past this coupe was allowed to develop a decent amount of corrosion in the tail cone. (It also has some in the center section but it's been deemed airworthy by an A&P-IA with knowledge of coupes, but we shouldn't let it continue to degrade so we're cleaning out the center section to alodine & prime the whole area.)

Anyway, I have been experimenting with cleaning out the tailcone. Simple Green Extreme does a great job of removing oils, but it takes *forever* to scotchbrite down to clean metal. I ordered some alumiprep to enhance the scrubbing. I am tempted to skip alodine and jump directly to self-etching zinc phosphate primer. (I'm hesitant to cram myself into the tailcone while slinging alodine - it's nasty stuff - and the coupe lasted 75 years with no treatment so I'm not trying to go overboard.)

So, who has experience crawling into the tailcone? So far I've been working on areas I can reach while kneeling on the seat but eventually I will need to get back there. Is it easy to damage the skins or ribs? Would removing the horizontal stabilizer help with access at the very back?

Thanks again - any advice much appreciated!