TParker Long-EZ Rebuild

[TParker]

On 6/3/2020 at 8:42 AM, Kent Ashton said:

It would probably be interesting for you to join  https://canardowners.com/       I think(?) they have scanned copies of past Central States Association newsletters in the site.  That was/is  a great newsletter.  When the world was building EZs and Van was just a little kid in knickers, people contributed a lot of ideas to the newsletters.  Very interesting reading.

I joined. Doesn't look like they have scanned copies of the past CSA newsletters (yet?).

[Jon Matcho]

On 6/4/2020 at 11:50 PM, TParker said:

Doesn't look like they have scanned copies of the past CSA newsletters (yet?).

You may already know this, but Terry will send you 34 years on a flash drive for $100. I'll put the info. up in the For Sale section here.

[TParker]

13 hours ago, Jon Matcho said:

You may already know this, but Terry will send you 34 years on a flash drive for $100. I'll put the info. up in the For Sale section here.

Thanks for the heads up!

I bought one as soon as I found out about it, got it about a month ago.

[TParker]

Been a while, much of it without much activity. But I have gotten some stuff done.

EM Extrusions: Did some stress calcs for landing loads, decided to leave them alone for the most part. Didn't want to do the surgery to add hard points for the bolts that missed and inadvertently cause more damage than I was fixing, so I came up with a laproscopic flox repair to locally address those.

Engine Mount: Cut the extraneous stuff off, blasted it, and painted it. Figured out what I'm going to do when I reinstall it to try to minimize/mitigate potential local EM extrusion cracking at the attachment points.

Nose gear: The retract system couldn't be rigged to have full extension (fuselage longeron level, proper nose wheel caster angle) and full retraction at the same time. Full retraction was also not flush. Ended up relocating the clamp on the gear leg, and modifying the gear strut tunnel. Tunnel wasn't pretty, and still isn't. The wheel well and gear alignment aren't great. If the wheel is a bit cocked in one direction, it will hang up on the wheel well before it fully retracts. Not sure if wind stream and the bit of vibration in flight will make this a non-issue; going to leave it be for now. Need to figure out a new nose pad/bumper; think I'm going to make one out of HDPE or similar to sit right in front of the strut, and maybe on the strut too.

Strake ends were filled with micro, and were cracking and delaminating; right side was worse, left wasn't too bad. Did the lower right first, tried to be clever but was a lot of work. Simplified it to just flox for the rest. Managed to screw up the left side because of how much filler there was on the outside, so a bit more work needed there.

Elevators: Spent a bunch of time on these. Stripped one side of one thinking there'd be a lot of filler and that would help balance. Basically no filler; the exposed surface looks ok, they're just heavy. Plans allow for 3 oz extra balance weight to the outer mass, doesn't say exactly how/where to add that. To make my extra 3 oz as effective as possible, I increased the moment arm and resized the cove in the canard to compensate; now they're in spec for balance and weight. Hopefully this wasn't a bad idea; don't copy me.

Ailerons: Similar deal, they didn't balance. These had a ton of filler on them, took about a pound off of each, but that wasn't enough. I've learned to love an angle grinder with a flap wheel for stripping stuff off, gotta be careful though. Balance rod was a steel tube instead of a steel rod, haphazardly packed with lead. Cut the tubes off, bonded on 1/2" steel rods instead. I know others have gone from the plans 3/8" to 7/16", don't know if anyone has done 1/2". Might alter the roll handling a little. Didn't see a max weight spec'd anyway, and there's a later CP that says (to deal with vibratory aileron hinge wear) to add more weight with no specified limits in order to balance with top surface level. Velocity ailerons are about the same size, shape, and hinge length and spec a 9 lbf max; mine are about 7 lbf without paint right now. 

Currently working on the gaps between the ailerons and the wings, they were way too tight before (like 0.005"). Plans call a spec for the chordwise gap between the aileron and the cove and I'm pretty much there now, need a bit of final prettying up; can't seem to find a spec for the spanwise gap. Also working on deflection; looks like the universal joint boot on the aileron torque tube hits in the wing and needs some extra clearance for full aileron travel, they're not too far off but shouldn't be the limiting factor. The bellcrank brackets in the wing root cove have witness marks from the rod end attachment bolt, and don't have the aileron stops (and never did, no holes). The aileron pushrods are all missing, so I'll have to make new ones once I get the wings on.

Edited January 26 by TParker

[Marc Zeitlin]

11 hours ago, TParker said:

To make my extra 3 oz as effective as possible, I increased the moment arm and resized the cove in the canard to compensate; now they're in spec for balance and weight.

Be very careful with making the mass balance longer - you still need to ensure that you can get full book value of TE down elevator deflection, but if the MB hits the inner upper skin too early, you can't.

[TParker]

8 hours ago, Marc Zeitlin said:

Be very careful with making the mass balance longer - you still need to ensure that you can get full book value of TE down elevator deflection, but if the MB hits the inner upper skin too early, you can't.

Thanks Marc! Appreciate the concern, and checked that as I was milling the cove out with the new weight taped on (thus that picture) before I made it permanent. 

[jridge]

Glad to see you're making progress again. 

Are the engine mount extrusions the stock 1/8" x 1" x 1" size or have they been increase in size?

How far down did you have to move the bracket on the nose gear leg to get full up/down movement?

What's going on with the engine and the cylinder corrosion?  Have you made a decision on that yet?

 

Jeff

[TParker]

21 hours ago, jridge said:

Glad to see you're making progress again. 

Are the engine mount extrusions the stock 1/8" x 1" x 1" size or have they been increase in size?

How far down did you have to move the bracket on the nose gear leg to get full up/down movement?

What's going on with the engine and the cylinder corrosion?  Have you made a decision on that yet?

 

Jeff

Extrusions are the stock size.

Not sure how far I moved the bracket (closer to the pivot, away from the wheel); I know I took some measurements to get a rough idea of how far it needed to go, and then I used the outer bracket, without the inner piece so it would cinch up on the leg, temporarily installed and testing it to get it right. I ended up marking an acceptable range on the strut to guide where to put the bracket when I bonded it back on. 

Haven't decided what to do about the engine, I bagged it up with some desiccant and left it in the corner; was hoping to find a good deal on a core or mid-time 320 at some point but haven't. I'll probably tear the 235 apart and rebuild it, probably with overhauled cylinders, that'll probably be the cheapest route to getting it flying. But I'm also toying with the idea of putting a Rotax in it (for stupid reasons), I want to get the wings on to see where the empty airframe CG is to see how much or little engine weight I can tolerate.

This weekend I opened up the aileron torque tube recesses to get full aileron travel, and started working on the spanwise gaps. I've got the travel I need now, gotta clean it up a bit and close it out (Maybe? plans call for extending the root layup in about an inch, but I can't see that it really serves much purpose. Gotta think about it). I found the spec for the gap, same 0.080"-0.200" as chordwise, on the same page of the plans, just didn't realize at first what the other cross section was. These were just as razor thin to non-existant as the others. I've got the right one done, left is up next.

Example before:

And after, at about 0.085",:

Edited January 28 by TParker

[Kent Ashton]

On 1/26/2024 at 12:17 AM, TParker said:

Nose gear: The retract system couldn't be rigged to have full extension (fuselage longeron level, proper nose wheel caster angle) and full retraction at the same time. Full retraction was also not flush. Ended up relocating the clamp on the gear leg, and modifying the gear strut tunnel. Tunnel wasn't pretty, and still isn't. The wheel well and gear alignment aren't great. If the wheel is a bit cocked in one direction, it will hang up on the wheel well before it fully retracts. Not sure if wind stream and the bit of vibration in flight will make this a non-issue; going to leave it be for now. Need to figure out a new nose pad/bumper; think I'm going to make one out of HDPE or similar to sit right in front of the strut, and maybe on the strut too.

Just thinking that if you move the gear leg clamp up the strut, it will increase the leverage of the nose-gear & weight which then transfers into the NG30s.  People have had them delaminate from the nose once in a while.  Perhaps there is a better way to get more extension by relocation of micro-switches if you have electric gear.  Also make sure the nose strut is perfectly vertical when on the gear.  If not it will castor in one direction and leave you thinking you have a dragging brake.

The nose opening is a big pneumonia hole and the only way I have figured out how to seal it is to build a door or cover on the strut which when retracted, seals against strips built into the nose-gear box.    https://www.canardzone.com/forums/topic/18661-kents-long-ez-project/page/23/#comment-72419

Alternatively, you might build a cover that seals against the bottom of the nose

 

[TParker]

10 hours ago, Kent Ashton said:

Just thinking that if you move the gear leg clamp up the strut, it will increase the leverage of the nose-gear & weight which then transfers into the NG30s.  People have had them delaminate from the nose once in a while.  Perhaps there is a better way to get more extension by relocation of micro-switches if you have electric gear.  Also make sure the nose strut is perfectly vertical when on the gear.  If not it will castor in one direction and leave you thinking you have a dragging brake.

The nose opening is a big pneumonia hole and the only way I have figured out how to seal it is to build a door or cover on the strut which when retracted, seals against strips built into the nose-gear box.    https://www.canardzone.com/forums/topic/18661-kents-long-ez-project/page/23/#comment-72419

Alternatively, you might build a cover that seals against the bottom of the nose

 

Thanks for the suggestions Kent.

Gear is manual, so the travel of the retract system is pretty much fixed; any more retraction angle and it will draw the spring/strut into the retract mechanism, and more extension angle is further over center and would reduce travel. I'll check the vertical rig of the strut.

I left sealing the nose opening as a problem for later; filed under nice to have, eventually, but not worth delaying the project from flying to solve.