brake cables revisited

[RMASS]

Guys, looked at the brake cable subjects and read that people are using 1/4 bowden cable for brakes with 1/8" cable inside. question somewhere I read use the ends on your present cables-Are we talking about the yoke that fits the pedal or is there something on the housing that hold it in the brackett? Have a 7AC housing is roughly 23' long with some sort of compression fitting close to the ends, with a bunch of tape wrapped around the shield ( I guess to hold it in the brackett). Well supossed to be close to the end. Is the best way to change both or just a cable? Cable frayed pretty bad at the wheel connection. Wagaero has cables in galv and SS for 30 odd dollars--Is this just the inside cable? (did not say). Someone showed a drain cleaner from home depot for the setup ??
Also door seal where how long-round or quater round style?
got the wing covered and starting on flying surface then fuselage slowly but surely
Thanks Ron

[RMASS]

it's 2/32 cable inside!! Ron

[Paul Agaliotis]

Ron,
I use the largest cable I can put in the Bowden cable, I'm thinking 3/32. If the Bowden is in good shape you can just snake in a new cable. I use a clevis at the pedal end and the adjuster at the wheel end. If you need to make new Bowden, I put heat shrink tubing over it to keep out any oil, dry lube (graphite) only here. Most Champs are missing the brake pedal return spring and bar. The release spring at the wheel is for the brake shoes not the pedals. The compression rings on the Bowden attach to the inside of the clamps. They restrict the Bowden from movement in both directions. I use galvanized cable for the brakes, it's a bit stronger than stainless.
On the door seal, see what fits during installation. You don't want to load it too much, it will break the door at the hinges.
Paul

[RMASS]

Thanks Paul, not only can I not read correctly I can't type either. It is 3/32 and Yes I need new Bowden and the shrink is an excellent idea. Yep missing the return springs. will have to look at the drawing and see what/where they go. This little champ was sure abused ( I guess like many). Wish I would have visited this site before I made my decision. much info from the group.
Where woulg I buy bowden cable home depot?
thanks again Ron

[Paul Agaliotis]

Ron,
Go out and buy a closet snake and chop it up for the Bowden cable. I take a standard nico press sleeve, cut it in half and run a taper punch through it to round it out. Slide it over the Bowden and use a standard nico press to set the ring. Go slow or you will crush the ID too small. You only need enough to hold on the Bowden secure.
The return spring uses a tube secured to the extra holes in the brake pedals. It connects the left and right pedals. In the center of this tube is a lug that holds one end of the spring. The little tab in the center of your fuselage at the firewall, under the floorboard, secures the other end of the spring. This interconnect tube also has the attachment for the parking brake.
Paul

[RMASS]

Well as said before it was abused during it's day and for only 1700+ hrs total time (I'm guessing from the log books/tach time from engine change), It has no parking brake or tube connecting the pedals. As everything else the log books were probably abused also!!!!!! do I need the parking brake? We are removing them from the 170's due to interference with brakes master cylinder plungers! I know this is a completely different set up but, is the parking brake either worth while or necessary. I'd like to have return spring on the pedals. Jury rig one on each side???? Ron

[Paul Agaliotis]

Ron,
I like the parking brake and use it for start-up. It's not required but nice to have, but you need the anchor point under the floorboard. And that's just one more piece to make or find.
You can build the cross tube at the pedals easy enough, just a tube with a couple of pins to the pedals and a single spring to the forward lug. The tube just kind of swings around as the individual pedal is pushed but has enough pull to return the pedals to their stop.
See if Joe A. or Todd T. have the drawings. If the plane is assembled pull the floor boards, it take half the day but is about the only way to do it right. I've straightened out customers mechanical brakes and they were amazed how well they work. Most were considering hydraulics but threw that idea out after they get the original brakes working correctly and adjusted.
Paul

[GWestphal]

Another spot for the bowden jacket is your local Yamaha 4 wheeler dealer. They stock brake and throttle replacement bowden material for 3/32" cable and figure out what you need for 2 and have him bring out what he has from the rear stock room for you to choose. Usually you can look at the machines on the show room floor and pick out something with a nice protective vinyl jacket on it to keep water out................Gordy in Minnesota.

[GWestphal]

Paul, question on your follow up notes about the 2-796 brake beam and 1-769 spring shown on page 51 of the 7EC parts books. Did the 7AC use this rod/beam if you didn't have the hand brake handle installation. My 7AC does not have this and I wondered if the torsion spring on the brake assembly at the wheel was the only spring part used to put tension on the cable. My Champ does have the spring tab welded on the lower front firewall fuselage cross tube but there is no wear in the hole showing that a spring was once mounted to the tab. What size diameter tube was used for the brake beam 2-796 and was a short piece of rod welded into each end to go through the bottom brake pedal hole with a cotter pin and washer for retention? Gordy in Minnesota

[Paul Agaliotis]

Gordy,
My guess is they would have them. There is really no way to return the pedals with out it. Now the parking brake is optional,but, I'm not sure the beam and spring was specific to the parking brake installation.
I believe the beam was 3/4 or 7/8. The beams I have use a pin only. Once installed it can't be removed unless the pedal is removed.
Paul

[GWestphal]

Thank you Paul for the additional info on the brake pedal return rod info. I will need to make one up and install before the boot cowl goes on. Thanks again...............Gordy

[MikeB]

Gordy,
How about some pictures of your project Champ? Sounds like it's coming along pretty well if you're getting down to installing the boot cowl.

Mike