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Would like to know what other people are using for wheels and brakes other than the original. Apparently there are two different length axles on gear legs. The earlier version was approximately 5.5 inches long and was for the 6.00 x 6 Wheels with 7.00 x 6 tires. The second version was for the later model aircraft (L-5E-1 and L-5G) and had an axle length of approximately 6.25 inches long and was for the 8.50 x 6 Wheels with 8.50 x 6 tires. So I have a NOS set of legs with the 5.5 axles and a set of L-5G legs with the 6.25 axles but they need some minor work (weld a tow bracket at the bottom of the leg and fix zerk fitting at the top). I would like to use the NOS legs with the shorter axles as they are correct for my L-5 42-98774 but I do not know if modern brake sets are compatible. I have heard some are using Grove wheels and brakes but I do not know what axle length they have and what kit number they are using.
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Hi Matt, The Grove wheels and brakes use long axles. You can switch axles by cutting off the tow lug and pressing the old axles out and the new axles in. I have done the axle change several times. Works well. (NOTE: the real early get legs/ short axles had an attaching bolt which ran vertically. The mid age short axle and late gear leg/a long axle had a bolt which ran horizontally. I have changed Mid and late axles only. I am not sure if the early are the same axle as mid age. ) Tow lugs are easily welded back on.
Grove wheels/ brakes are great quality components. The people at Grove should be commended for helping owners of older aircraft ( and experimental too) keep the planes flying with safe options.
More brake info– (start yawning:) “Cleveland “type disc brakes are not new to airplanes. Their were many successful conversions made starting in the 70s?(60s?). But disc brakes “conversions ” have had some bad press due to improper matching of airplane master Cylinders and and wheel brakes. Cleveland made ( makes) over 100 sizes of brakes and probably 30 sizes of master cylinders. So when mechanics start to “Mix and match” components. You need to pay attention which does not always happen. This leads to sensitive or “too strong ” brakes or the ineffective ones.
I get this comment often on my L-4 with Cleveland brakes……. ” the two piston Cleveland is way too strong a brake for a Cub . It will put you on your nose.” Yes it will if it had Cleveland master cylinders installed, but mine are stock cub Scott master cylinders and they match well the 2 piston wheel brakes.
The “Cleveland” style disc wheel brake is a Low volume , High Pressure ( LV HP) brake piston system. Meaning ,the amount of brake piston travel only requires a small amount of fluid to work ,but it requires a higher pressure generated by the master Cylinder to “push” the piston hard enough to squeeze the brake pads properly.
Our stock L-5 expander tube brakes were High Volume, Low Pressure ( HV LP) systems. The wheel brake( expander tube) needs a lot of fluid to move but it had a much lower pressure because of the huge surface area being used.
SO… ‘Cleveland” brakes used small volume ,High pressure master cyls which were small diameter (maybe .50-.625″) and could generate pressures to work the small area wheel cyl pistons( relative to expander tube areas). Our L-5 uses a 1.25″ piston and travels much farther that a High pressure type.
The problems can occur when you mix LV HP components with HVLP . I have seen L-5 with stock masters and disc brakes and some “Cleveland” masters and disc brakes.
The Grove engineers will work with you and select a wheel brake size witch will match the power of the stock Wagner 1 1/4″ dia. master cylinders well. I have flown a ‘G” with that set up and it was great. (to me ,a perfect brake holds at run, up but barely:).
The brake assy was # 29-1005A The Wheel was 65-1003A. It required special sized axle spacers to be made which will position the disc in the correct spot relative to the Torque plate which is bolted to the gear leg flange.
This installation requires an FAA field approval to go on an L-5 because it is not listed on the Grove Eligibility list. I can help you with that paperwork if you choose to go that route.
One last note – Blah, Blah ,Blah ,blah…….. The brake fluid used in the system may now become an issue. You may need to run DOT 5 Silicone fluid in the brakes if you are matching automotive seals( master cyl) and aircraft seals ( wheel cyl O rings).
Sam out!!
Nope not done yet!!!! You may consider contacting Grove ( full name is Grove Aircraft Landing Gear Systems in El Cajon ,CA) and see if they can make a brake installation with the short axle. Give them the measurements from the gear leg bolt flange to (A) the start of the threads( for the axle nut) (B the total length of the axle including threads, axle diameter, Gross weight of L-5 and existing wheel/tire size. Who knows? they may be able to adapt a set to the short axle . Now I’m done 🙂 ST
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Well, I cannot shut up today;) . The Cleveland brake calipers were very often made of magnesium. Light weight, strong. But in normal wear the outer surface treatment will wear through in the piston bore area and that will start corroding the brake housing assy. and leaks will occur. Expensive to replace. Grove uses Aluminum brake housings.
I read Rich Saylors post and agree. Expander tubes brakes ,when properly working are great for L-5s ( my personal favorite) . But I also know that part are getting tough to find so Disc brakes serve as a good alternative.
ST
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