Rudder Pedals: Long Bolt Trick

[maus92]

I did the long bolt and springs mod on my RV-8A. However, one of the master cylinders developed a leak on top that required a rebuild. The rebuilt cylinders had enough "return" / recovery to eliminate the need for the springs. Kept the long bolts though. Note that the spring installation was not the cause of the leak; the shaft had deformed which allowed fluid to escape under heavy braking. Hopefully the long bolts will prevent the master cylinder from twisting, and reduce wear on the shaft.

[MikeyDale]

I did the long bolt and springs mod on my 7 and I still hear the brakes drag on occasion when I'm on a paved runway. But I just inspected the brakes and after 2 years and close to 300 landings, found very little wear on the shoes!

[rapid_ascent]

After playing with the brake springs way too long I've finally settled on my spring configuration. I ended up just using nylon washers and the 0.5" OD spring. The slightly larger spring actually looked bigger so I decided against it even though I had tracked down sleeves that would fit inside. Now I have a ton of parts I'm not going to use but at least I got to evaluate all the options. My configuration now looks like Bruce's.

If you are interested in any of these extra parts PM me.

[Mel]

Originally Posted by MikeyDale

I did the long bolt and springs mod on my 7 and I still hear the brakes drag on occasion when I'm on a paved runway. But I just inspected the brakes and after 2 years and close to 300 landings, found very little wear on the shoes!

All disc brakes drag a little by design. There is no return spring on the caliper piston. This keeps the discs clean.

[PG13]

If you just order the parts listed, they either changed part numbers or something happened because the formula in this thread doesn't work. The sleeves are perfect, they slip right inside the M/C. You need a spring with an ID of 5/8" of an inch. I got the bag of springs and basically have a bag of springs I'll never use now. OSH had some long ones that worked great, cut in half and tweaked at the ends. The wire thickness of .50 gauge wire spring seemed a lot more appropriate to me than the .41 or the .6?
Good middle of the road type.

[ppilotmike]

Originally Posted by rapid_ascent

I just finished this step in my build. I did use a 12" #12 bit to make sure the pedals rotated freely on the long bolt.

I noticed that the tabs for the master cylinders may need to be adjusted a little so that the are aligned properly. Otherwise there was some additional resistance.

I went ahead and ordered the springs and etc. from McMaster. Cheap insurance in my mind. PM me and I can send you 4 springs. They are sold in bags of ten. Oh and if you want nylon washers I have those too. I didn't like the shoulder bushing setup called out in a related thread where the 0.5" diameter spring rested on the end of the shoulder bushing.

Ray,

I sure would like some of your extra springs and washers. I'm at the point where I'm building my rudder/brake pedals right now. My mailing address is below:

8563 W ILIFF AVE
LAKEWOOD, CO 80227

[rapid_ascent]

Mike, I'll take a look and try to find those parts. PM me if you don't hear from me and I forget about it.