Long-EZ Engine extrusions and rudder pedal mod

[jppt2000]

Fellow canardians,

 

I am relocating my ship's brake master cylinders and installing them behind Dale Martin's rudder pedals.

I am also upgrading the ship's engine to an IO-320.

 

The Long EZ plans call for the original plans brake cylinders to be connected

between the aluminum engine mounts on the firewall.

The lower mount carried the end of the brake master cylinder through a bracket-CS73, while the top anchored a lever-bellcrank, which converted brake pedal motion into a "push" on the brake cylinder actuator.

 

Doing this mod on my Long-EZ, leaves an unused 3/16" hole in the aluminum "L" angle extrusions at (as a bonafide COZY mk.4 builder flyer suggests) near their point of max bending - not a desirable trait in an engine mount.

 

Has anyone ever heard of a fix to get rid of this hole without doing

major surgery on the extrusions, essentially replacing them?

 

Filling the hole with a weld will probably conduct heat to the nearby

spar and anneal the aluminum mount.

Reinforcing it with an attached piece of aluminum relies too

heavily of the attachment method of the reinforcement piece - epoxy?

rivets? (more holes).

 

My instinct says reattach the "old plans" bracket, without its associated brake master cylinder with its "old" countersunk screw.

 

Any ideas welcome.

[Drew Swenson]

If you Leave CS-73 in place on the lower extrusions, I see zero difference with the brake either attached or not. For the upper 2 extrusions, remove and replace with an extrusion with a 1/2 inch taller verticle web (for the heavier vibrating mass). The replacement will obviously remove the hole in question.

 

The extrusions are floxed and bolted to the upper longerons. Use a magnetic cheap studfinder to find the back of the bolts on the outside of the turtledeck area. Mark all 4 locations then drill through the fuselage to get access to the back of the bolts. Unbolt them and remove. Use your dremel to carefully dremel off excess flox around the aluminum/wood joint---don't dremel on the longeron itself. Once cleaned up, use a pretty hefty sledgehammer to beat the back of the extrusion. You need to break the bond in shear---and it will take quite a bit of force---and it will beat up the back of the original extrusions. Make a jig from wood, bondo and bushings so that you can use the old extrusion to match drill the holes for the new extrusions.

 

The rest should be easy from here.

 

You will also need to upgrade your engine mount. Dave Ronneburg did mine----Cozygirrls sell the mount outright---and I believe they can modify your existing mount.

[jppt2000]

I was afraid of this.

[Drew Swenson]

I was afraid of this.

The work I mentioned above is actually pretty easy---and is the least time consuming piece of the whole thing. You can swap out the extrusions in less than a day. I am not a welder---so I farmed that out. Cowls, plumbing, throttle cable, baffles, oil cooler mounting, wiring, etc takes a lot longer. My O235 was fine with the brock throttle bike cable. The O320 required a push-pull cable---also not that hard---lots of tips from me on the bulletin board. But there are a lot of little things that have to be done to accomplish this feat. Swapping same engine types can be done in a day---putting on a bigger engine involves more work. You will also need a new prop to absorb more rpms---and you will need a prop extension----your old one won't work.

[Kent Ashton]

Seen this idea?

http://www.vortexgenerator.net/EngineMount.html

 

Nice but I'm not sure it's worth the trouble. However, if I were replacing aluminum extrusions, I would certainly go to steel angles. Worth the piece of mind, I think.

[jppt2000]

Thanks Drew and Kent!

It's gonna be hard to tell folks I used a precise, delicate tool, such as a sledgehammer on the plane.

But it looks like it's the safe way to go.

BTW kent, is there a CP reference for steel extrusions?

Hey maybe the Cozy Girrrls might find these extrusions worthwhile to manufacture.

Thanks so much for the advice.

[dkreidel]

I was one of the first (if not the first) to knock out the old extrusions and install 4130 top extrusions in 1986. The lower aluminum extrusions are okay as is, and as several have noted a large hammer is required to break the epoxy shear line.

 

Dick Kreidel

N888EZ 2,680 hrs

[Kent Ashton]

BTW kent, is there a CP reference for steel extrusions?

 

Probably.

 

The yield strength of 2024-T3 alum is 50000 psi, mild steel 53700 and 4130 is 63000 psi.

http://www.onlinemetals.com/steelguide.cfm etc.

 

There is plenty of mild steel angle around. I have not encountered 4130 angle but a plasma cutter and a grinder will make some angle from 4130 square tube pretty quick. 4130 square tube is available many places.

 

OTOH, if you double the thickness of aluminum angle you're using now, you'd double the strength and it could turn out lighter.

 

Math! Ow, my head hurts!

[dkreidel]

Probably.

 

.

 

There is plenty of mild steel angle around. I have not encountered 4130 angle but a plasma cutter and a grinder will make some angle from 4130 square tube pretty quick. 4130 square tube is available many places.

 

 

That is a good idea! I should have done that - i used 1.5"x1.5" 4130N barstock and spent a lot of time on the Bridgeport turning the handles. I went to .150" with a nice fillet radius.

 

If using aluminum I recommend going to 3/16" material to lower the bearing stress and prevent brinelling the 1/4" fastener holes.

 

Dick

[jppt2000]

That is a good idea! I should have done that - i used 1.5"x1.5" 4130N barstock and spent a lot of time on the Bridgeport turning the handles. I went to .150" with a nice fillet radius.

 

If using aluminum I recommend going to 3/16" material to lower the bearing stress and prevent brinelling the 1/4" fastener holes.

 

Dick

Thanks!

Much appreciated!

[longez360]

I was one of the first (if not the first) to knock out the old extrusions and install 4130 top extrusions in 1986. The lower aluminum extrusions are okay as is, and as several have noted a large hammer is required to break the epoxy shear line.

 

Dick Kreidel

N888EZ 2,680 hrs

 

I followed Dick Kreidel's 4130 system with my O-360 with the exception of using 4130 all 'round. I believe one guy here in Aus had them machined, but I had them bent to the OD of the engine mount tube. Mine are 1" x 1".

 

Thanks Dick. We've never met, but good to see your name around the traps again. N888EZ is a beauty, I have not seen 26EZ but understand you and your late dad sure know how to build aeroplanes.

 

All, add this guy to your list of people who know their way around EZ's at the Mike Melvill level/category.

[dkreidel]

Hi Wayne;

We haven't met, but did speak on the phone many moons ago. 26EZ was pretty spectacular, and now that Jon Karkow (ex-SCALED, currently at ICON) has it I expect it will be even nicer. It had enough instrumentation in the rear cockpit to fly an ILS approach from the backseat!! Jon has it down for some modifications right now, but I'm sure it will be stellar when he's finished. As an example of Jon's prowess, he was the lead designer and program manger for the Virgin Global Flyer. It is, in essence a fixed gear Berkut. It is one of the best X/C planes I've flown; but ended up heavy at 1050#. There is nothing like a light LongEZ with a big engine

 

Thank you for the compliment - but I'm certainly not in Mike's league. I have built 2 LongEZ's and a Limo EZ, so I do know my way around them.

 

Dick

[gullikson]

Hi Dick an Wayne,

 

Did you make the 1.6" L extrusions and the 1.6" x 2" plates that mate to the upper engine mount extrusions out of 4130 as well?

 

Thanks,

Greg Gullikson

[dkreidel]

Hi Dick an Wayne,

 

Did you make the 1.6" L extrusions and the 1.6" x 2" plates that mate to the upper engine mount extrusions out of 4130 as well?

 

Thanks,

Greg Gullikson

;

 

 

Hi Greg,

 

The 1.6" long "extrusions" were 4130, but I used aluminum for the plates. Almost 3,000 hrs on the plane and no motor mount/extrusion issues

 

Dick

[gullikson]

Thanks Dick. This is a bit off the extrusion point but....

Did you extend the third OML ply of UNI on your fuselage full length in anticipation of the O-320 or are your fuselage layups pretty much per dwg?

Same question for the 3" wide UNI layup at top of fuselage that stiffens the upper longerons?

 

Greg

[longez360]

In my aircraft I made my engine mount angles (formerly extrusions) and plates from 4130. Dick's system of 4130 up top and alum plates is fine.

 

I ran all my UNI layups full length.

[gullikson]

Well, I can see now why Dick machined his 4130 1x1 angles for the engine mount extrusions... I am unable to find 4130 angle anywhere, only A36.

Wayne, did you find 4130 1 x 1 x 1/8 material in AU?

[gullikson]

Wayne, found your old post about bending the 1/8 4130 to make your four "extrusions".

Cheers.

[dkreidel]

Well, I can see now why Dick machined his 4130 1x1 angles for the engine mount extrusions... I am unable to find 4130 angle anywhere, only A36.

Wayne, did you find 4130 1 x 1 x 1/8 material in AU?

I' somewhat relieved to learn that I did look hard enough for 4130 angle - it doesn't seem to exist anywhere and it was very reluctantly I did the milling on chunks of 4130. Getting a clean fillet radius w/o any tooling marks took a lot of effort. Airplane #2, N26EZ used 3/16" x 1-1/2" 2024 aluminum on all 4 motor mount extrusions w/o any difficulty - it used an even heavier IO-360B1E

 

Dick Kreidel