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Messages - MacGyver

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1
Hangar Flying / Varieze nose leg needed
« on: November 04, 2006, 11:20:51 AM »
The stock Long-EZ nose gear strut, as currently configured, is thicker, fore & aft, than the original VariEze strut.  It may be a very snug fit if the airframe incorporates the pre-fab strut cover that is installed between the NG30s.  It will not be a "plug & play" procedure.  

When replacing, make sure you duplicate the overall geometry of the old strut.  This can be done on the bench.  You need to be able to duplicate the exact angle that the strut makes with the upper pivot axis (think of a "T", with the pivot axis being the top section, and the strut being the vertical section).  By bolting the upper pivot block between two pieces of wood that are affixed to your bench, then placing a fixed index piece on either side of the lower end of the strut, you can maintain this same angular alignment when you integrate the new strut with the upper pivot block.  You need to make sure the index pieces for the lower end will also accept the new strut (i.e. if there are any width differences between the respective struts, you need to be able to accomodate them, and still maintain the correct geometry.).

Alignment of the lower pivot & nosewheel fork is best done on the airplane, not only to ensure the net length is OK, but to also ensure the lower pivot's vertical axis is truely vertical, and that the caster angle has the proper "negative" inclination.

Most of the above is all based on a nose gear re-build I did for Dave Koester a while back for his Long-EZ.  I did the build-up of the lower end off the airplane, but this was a case of a Long-EZ strut/Long-EZ strut replacement.

Good fixing!

2
Hangar Flying / Roncz canard
« on: July 19, 2006, 06:44:42 PM »
Eric,

The hidden rudder bellhorns are not applicable to the VariEze - there is really no room in the VariEze winglet for such an arrangement.  As for the Roncz, it was never tested/approved for the VariEze.  A few builders (2 that I know of) have used it (cut down in span) on the Vari, but such an installation & testing is not for the average soul.

Overall, I would recommend a series of small/incremental changes to your new airplane over time, rather than a whole bunch of significant or Major Changes in close proximity.

My 2 bits,

3
Hangar Flying / My Long-EZ nose gear won't stay up!
« on: July 19, 2006, 12:02:07 PM »
A loose NLG system can be fixed in a variety of ways.  The ratchet installation is a nice one.  Note that this part was not produced by Brock, however.  In addition, to bore the hole through the center of the ratchet, the metal was annealed, drilled, then re-heat-treated to achieve the original hardness (an annealed ratchet core would not last terribly long).  I believe the NLG ratchet assembly was sold by an EZ builder, back in the 80's and 90's.  I cannot recall the gent's name.

Overall, I would avoid band-aiding a NLG system that tends to lower itself when retracted.  This is a sign of looseness, and could show its potential ugliness during landing or taxi.  I had a reasonably tight system on my first VariEze, and while taxiing at Mahlon Sweet (Eugene, OR) many years ago, I had the nose gear collapse.  Yes, the sucker was all the way down (and "locked" too).  A perfect combination of jostles (caused by taxiing over a series of ruts on the ramp set up related oscillations (up and down) of the nose.  After about 6 - 10 bounces, WHAM!  Down she came.  Addition of the ratchet was a must at that point, in spite of having a properly rigged retract mechanism (per the CPs).

For what it's worth,

4
Hangar Flying / VEZE on Ebay
« on: July 19, 2006, 12:03:24 AM »
Noel,

Ya gotta talk to me about the technique for now, and sans anything written, it is easier to show & explain than describe it in written form here.  Suffice to say that a transfer tool is made with precision drill bushings, potted in with tooling stone (or similar, like dental plaster), so as to pick up existing hole position and angularity of the eight 1/4 inch holes common to the c-section fitting area and the composite spar buildup.

This approach works well, and is superior to any machine shop approach - we use such "on-the-spot" transfer tooling techniques when necessary for airframe mods or repairs on the big birds.  Work severy time, and is cheap.  See this forum for a notation from Drew Swenson on how he did his engine mount extrusion replacements this way (topic was "Major Alterations" or, "Canard Vortex generators").

Happy to show you the basics if you want.

Cheers,

5
Hangar Flying / VEZE on Ebay
« on: July 18, 2006, 05:08:40 PM »
The fitting can be replaced (i.e. old Brock fitting replaced with a new Brock fitting), without need of a machine shop.  I have a retrofit process that enables one to do it with excellent results & minimal tooling.  Just takes time, patience, and attention to detail (along with potted drill bushings, retention framing, etc.).

-Joe Person
EAA Tech Counselor 4418
VariEze N79JN
Bothell, WA  (KPAE)

6
Hangar Flying / Extending Strakes on a VariEze
« on: July 13, 2006, 09:00:22 AM »
Al Fink did extended strakes on his VariEze, and tested the airplane extensively.  The airplane flies well.  I would not worry about airframe stress in this area of the fuselage, but one must still do some re-design to account for the revised strake set-up.  Al is a very experienced airframe engineer (among other things) - he did not make the mod willy-nilly.  Contact me off-line (ezejoe@comcast.net) to get Al's contact info.

7
Hangar Flying / VariEze First Flight Inspection
« on: June 16, 2006, 06:43:14 PM »
The VariEze Owner's Manual gives the basic criteria for first flight, etc.  If you don't have a copy, this website has a .pdf version available in the Downloads section.

8
Hangar Flying / VEZ Main Gear geometry
« on: June 02, 2006, 11:22:53 PM »
Robert,

You are probably better off aligning the axles to have proper toe-in and camber when the main gear is under load, unless your gear shows signs of strain/damage (fractured paint/filler, etc.).  Localized application of any stiffening plies would have to be done carefully - it is simpler to do an alignment of the axle, assuming the main gear's sturctural integrity is satisfactory.  I have seen several examples of unsymmmetric gear flexure on the VEZ, mine included (my gear flexes more on the right side than the left, for no known reason).

I did the final alignment of my VEZ axles this way, measuring toe-in and camber of the wheels with the airplane loaded near gross weight.  You need to plumb-bob and chalkline the centerline of the airplane, measured from BL 0 at the firewall, to the centerpoint of the nose gear fork pivot.  Using level straightedges along the wheel outer rims allows you to measure toe-in - I like about .25 to .50 degrees, total toe-in, under load.  The camber angle is easy to measure - I like a 0 degree camber angle.  Minor camber & toe-in adjustment can be done with shims & flox.

You can take all the critical measurements of the wheel alignment under load, them relieve the gear to do your work.  You can mathematically determine the thickness & location of any shims.   If you have the ability to machime a thin tapered shim from 2024-T3 aluminum, that is a good way to do it.  Make sure any shim you install is "captured " - all shims should have boltholes to allow them to be constrained by the .25 bolts that attach the axles to the strut.

Study the plans to see how the initial alignment of the axles is done as well, if you did not builkd the airplane.

Any questions, shoot me an email.

Best regards,

-Joe Person
EAA Tech Counselor 4418
VariEze N79JN
Bothell, WA  (KPAE)

9
Hangar Flying / Re: Long EZ on ebay
« on: May 03, 2006, 12:33:13 PM »
Quote from: "Bruce Hughes"
Hi Noel and others

Mike Melville is in a class by himself.   NOBODY can build a Longeze
with all of the layers of glass, etc. at less than 880 lb. [end quote].



Dunno - Clark Lydick and I built N777CJ back in the early-mid 80's - Weighed 860 pounds, with a huge LORAN (in the fwd end of the right strake), dual Nav-Coms (the old RST kit-builts), essentally a full IFR panel, and all weighed on very well-calibrated scales.  N777CJ was propelled by an O-235-L2C, and would true out at 205 mph at 8000' at full-bore.  We figured the "day VFR" version of N777CJ would have been in the high 700's.  I've done 2 VariEzes myself in the high-500/low 600 pound range.  IT CAN BE DONE, with excellent workmanship (begins with the foam cores), proper laminating techniques (and I've never vacuum-bagged), and attention to EVERY detail on the airplane.  I swore that if I were ever to build a LEZ, it would weigh less than 800 pounds.

10
Hangar Flying / Trailering an EZ
« on: January 29, 2006, 01:51:57 AM »
Kevin,

If you could wrap (securely) and pad the wings and canard, and tie them down on a flatbed, should be no problem.  I'd plan on doing the best job possible protecting the fuselage & canopy with covers too, for trailer transport.  I helped a friend move a Long-EZ on a trailer 20+ years ago, with no problems.

The truck with the lift gate does make it a cinch - I just brought my Eze home for the winter for some upgrades too, and will use the truck method again when I relocate the airplane to it's new home at Paine Field (Everett, WA) this Spring.

Good luck!

11
Hangar Flying / Trailering an EZ
« on: January 28, 2006, 08:31:14 PM »
Kevin,

Of course, if you are planning on trailering as a means to avoid having to hangar the airplane, I can contact Mike Drew (He's here in the Seattle area as well), and have him contact you.  Mike had a fully enclosed trailer for his Eze, and it was quite a nifty arrangement.  I believe he took 30 to 40 minutes to set up or take down the airplane.

Cheers,

-Joe Person

12
Hangar Flying / Trailering an EZ
« on: January 28, 2006, 02:03:40 PM »
If you have the option, using a 24-foot-box truck with a liftgate will accomodate an Eze nicely.  The fuselage is rolled onto the liftgate with the tail-end facing forward, and with someone holding the nose (gear retracted), the lift gate is raised.  Best to chock the wheels on the gate with 2x4's and clamps.  Roll the airplane into the truck.  Chock the wheels, and secure the nose with straps wrapped around the upper section of the F-22 bulkhead, and secured on each side of the sidewall of the truck.  Make sure you pad the prop hub (take the spinner off, if so-equipped) with a folded up moving blanket.  Put a pad under the nose as well.

The canard can be wrapped well with moving blankets and secured hanging from one side of the wall.

Wrap the wings and lay them flat, with the winglets on either side of the nose, and secure via the tie-down holes, and with soft nylon rope through the wing fittings.  This arrangement will travel well for over 1000 miles.  Been there, done it.

Transport in such a truck eliminates all potential for roadrash, rock dings, etc.  If only going a short distance, the trailer is fine, but at 50 MPH, I believe the chance for rash & FOD damage is fair.  Structurally, the winglets will be fine in all wind factors.  The winglets are built to withstand something on the order of a full 90-degree sideslip at the 180 knot level, as I recall.

Good transporting,

-Joe Person
VariEze N79JN
EAA Tech Counselor 4418
Bothell, WA  (KPAE)

13
Hangar Flying / Spider Box
« on: January 28, 2006, 01:08:43 AM »
Epoxy won't bond to aluminum????  Yikes!  I'm never getting on a modern commercial airliner again, and I'd better quit my day job as well!!!  

The epoxy actually bonds to whatever oxides are available on the aluminum itself.  This is why we use either phosphoric acid anodize, or similar procedures, to prepare aluminum alloys for bonding.  The better the "bond strength" of the epoxy to the oxide, and of the oxide to the aluminum, the better the bond.  And yes, we do use epoxies, as well as other adhesives to bond aluminum in aerospace.  It works quite well, as long as one does not include a fibrous matrix retainer or other media into the joints that can wick moisture over time (remember Aloha Airlines???).  As for the requirements of an intake spider, I'd not worry about the criticality of the bonding.  The naturally-occurring oxide layers that form should be quite satisfactory for the needed strength in the spider box.

-Joe Person
VariEze N79JN
Bothell, WA (KPAE)

14
San Diego EZ Squadron / VariEze back seat
« on: December 07, 2005, 12:22:21 AM »
Noel,

Remember, my back seat was cushioned and contoured for maximum comfort for my 5'8" far-better-half - with stock cushions, your fit would have been a bit more comfortable.  I've spent 9 hours straight in the back seat of a Long-EZ (when I weighed 185), and felt fine.  The Stock VariEze's rear seat is probably best suited for passengers who are 5'10" or less, and who are not over about 150-160 pounds.  

My Eze is one inch wider, from firewall to nose bulkhead.  I did this primarily for back seat comfort.  I have taken a 245-pounder aloft, and although he was tight in back (I put in a set of stock cushions), he was not too bad off (try putting same person in the front seat of a C-150, for example).

My nickel's worth,

-Joe Person

15
Hangar Flying / heat treating 2000-series aluminum alloys
« on: January 17, 2005, 02:04:47 PM »
Regarding heat treating 2000-series aluminum alloys:  If the information was meant to infer that one could make existing aileron tubes even stronger by heat treat - bad answer.  If the tubes are made from 2024-T3 (as they should have been originally), there is no way to ever make them stronger by additional heat treat - in fact, they will never again be as strong as when in the "from the mill" -T3 condition.  For one to take this suggestion a different way, and start with tubes in the "0" condition, the best you will get is the T42 condition, which is not quite as stout as T3.  Most "aircraft" aluminum alloys will have better conditioning from the mill, versus heat treats in the field.  "0" condition is specifed where some requisite of manufacture (e.g. forming) needs to be done prior to heat treat.  A good example on our airframes are the hinges on the GU elevators - they start out as 2024-0 and are then heat treated to the T4 or T42 condition after forming.  They are not, nor will they ever be, in the T3 condition (as has been erroneously given in the plans, as I recall).

Stay away from your own attempts to heat treat your aluminum components if they are "per plans" - there is no good reason to do so.  As for fireproof controls, that information is in the CPs.

-Joe Person
Tech Counselor 4418

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