Replies to This Discussion

Permalink Reply by John Austin on December 4, 2017 at 8:05am

When posting in the Open Forum, no one has any idea which Zenith airplane you're referring to, so it would be helpful to state in your post/request if you're discussing the 701, 750 STOL, Cruzer, 801, 601/650, etc. 

However, I looked up your member info and it says you are building a STOL 750.  When I built mine 6 years ago (Edition 1 with Edition 2 upgrades), there was no specific brake line routing.  I have standard pilot-side brakes and ran the lines down the center console area to an optional parking brake valve:

... and then down the lower sides of the center tunnel on the inside of the tunnel, securing both the brake and braided stainless fuel lines with "butterflied" or doubled-up Adel clamps:

... and then turned and went across the inside of the bottom fuselage skin in the space underneath the baggage floor, through a grommeted hole to the outside and down the back of the gear leg through a protective channel I made:

Some choose to use a couple of 90 degree fittings to make the brake line transition from inside to outside but I found that a slightly oversized, grommeted hole provides just enough "give" to let the line angle through the hole without kinking (I like to eliminate joints and connections whenever possible to eliminate the possibility of leaks).  Some go with stainless braided brake lines but I had an aeronautical engineer tell me they used the exact same nylon brake line on some of his company's (Boeing) hydraulic test rigs and it will withstand pressures far in excess of what can be generated with the Matco brake cylinders. As you can see on the exterior picture, I tried to keep the line protected by the gear and gear support as much as possible to avoid it being accidentally snagged.

Also, Zenith now sells a fairing that goes down the rear of the gear leg to fair-in the brake line.  Mine was simply a piece of 6061T6 tubing held by a couple of clips with tabs stuck to the back side of the gear leg with 3M exterior adhesive pads.  I reasoned the foam-cored adhesive pads would provide a little "give" with the gear leg flexion and be superior to rigidly attaching with screws, etc.  This has worked well for 5+ years and 500 hrs!  Running the line down the rear of the leg protects it from damage in off-field landings should you roll through some brush, etc.

Hope this helps!

John

N750A

• ▶ Reply

Permalink Reply by geo. keyes, jr. on December 23, 2017 at 10:50am

hello all,

i am building a Cruzer...  i have been wondering about an effective method of securing the brake line down to the discs.  Any chance folks would be interested in showing off their attachment methods for a brake line protection tube to the main gear?  i'd be interested in any other ideas that builders have installed as well.

the above photo is my most likely routing and i like the aluminum tube, but how is it secured?

also, john's response states that 6 years back "there was no specific routing".  Is there now?

thank you all,

geo.

• ▶ Reply