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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
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
Hi Bill,
Remember that section of the manual is “finishing Specifications” and is for work in the ‘Field”. That is not necessarily what the factory supplied… i use a product by Alliance Coatings in El Cajon , CA. the WWII Green primer is their MIL-PRF 85285 Lusterless ( flat) <span style=”text-decoration: underline;”> Primer Green</span>. In the past ,we had a custom color match made off of many good Original primer samples. This product is super close!! It is the green which is seen in many WWII aircraft. The “yellow” zinc chromate or “yellow” primer is called “<span style=”text-decoration: underline;”>Zinc Green</span>” and is almost the yellow in color.
You are looking for the “Primer Green” color for the interior tubing.
The paint is actually a top coat color and will need a good primer installed on the metal first. It is almost impossible to find that color in an actual primer anymore.
It is expensive and a 2 part paint. It takes 2 days to dry properly , but it is consistent in it’s color and level of gloss (flat). It is the best I have used.
Sam
