Slowing working on the Cleveland brakes. Sent off the brake lines to get rebuilt and while they are gone I’m working on the calipers.
I had bead blasted the outsides and cleaned them well, but because the aircraft had sat since 1983, there was residue of the O-ring on the bore of the caliper.
I used some X-50 anti-corrosion spray and a scotchbrite to clean that area up. In the picture below you can just see that ring in the bore of the caliper on the Left and how clean the one of the right is.
Aslo found out Univair sent me the wrong -O-ring for the Piston.
I was out at the hangar tonight, working on Brake master cylinders and the Cleveland calipers. I put the fuselage out of the hangar in the grass so I could have more room to work. Well the Sun set was nice and I thought I would take a Glamour picture.
As she sits here, she has all new control cables installed with all new Pulleys. Also rebuild control column and Dual brake / rudder pedals.
Working on Floorboards and Brake lines now, next will be 1/2″ fuel lines and selector.
Well, this weekend I wanted to get the tailwheel built up and mounted on the airframe so I can roll the darn thing around. Well as I gathered all the pieces together and started a final inspection, I noticed the Scott 3200 wheel bearings were pitted.
Next comes the research to replace them. The Bearings are Timken A4050’s with a race A4138. Looking at the regular places like Univair, Aircraft Spruce and others, these bearings are very costly considering their size. To get the Bearings, races and dust covers is over $270.
If you look up the timken A4050 on its own, you can find the bearing for MUCH less, like $40 for two bearing and race sets!
So now you are asking why? Why are the SAME bearings 1o times more expensive from the Aviation parts houses? Well I found an interesting post on this McFarlane site stating that the Aviation grade of the A4050 actually has a part number A4050-20629. https://www.mcfarlaneaviation.com/products/product/A4050/
You can see that the A4050-20629 has the FAA/PMA stamp and appears to be a black roller cage.