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Important Update regarding Open-EZ Rev 5 Templates


Jon Matcho

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*** IMPORTANT ***

Inaccurate reference measurements have been identified in the Open-EZ Revision #5 Templates that can result in improper airfoils.  In 3 of the 14 templates the X and/or Y reference dimensions are off by exactly 1 inch.  This was a result of human error (mine) where I used the 1" mark on the tape measure as "zero" (for accuracy), but forgot to subtract 1" at the far distance.

Specifically, the following is the status of the Revision 5 templates:

  • A1:  23" x 16.5" is good
  • A2:  23" x 17" change to be written as 23" x 16", building to incorrect dimensions will result in:
    • The GU canard core templates will be ~1/4" less thick than they should be.
    • The instrument panel bulkhead will be ~1/4" short (relative to the waterline).
    • Printing and not scaling to match the measurements would have been better in this case (assuming a ~1/8" typical "first try" inaccuracy of most large format printers).
  • A3:  23" x 17" is good
  • A4:  23" x 17" is good
  • A5:  23" x 16" is good
  • A6:  22" x 17" is good
  • A7:  23.5" x 18.125" change to be written as 22.5" x 17.125", building to incorrect dimensions will result in:
    • Just a bigger reference drawing, since the aspect ratio is preserved 1:1.
    • Printing and not scaling to match the measurements would have been better in this case (assuming a ~1/8" typical "first try" inaccuracy of most large format printers).
    • Ary Glantz has an excellent write-up on his blog site how he discovered this issue and corrected it (although Ary's workaround is unnecessary if you just use the corrected measurements indicated in red here).
  • A8:  23" x 17" is good
  • A9:  23" x 16" is good
  • A10:  17" x 22" change to be written as 17" x 21", building to incorrect dimensions will result in:
    • A longer main wing chord and overall skewed hotwire templates at butt-line 55 and 23.
  • A11:  23" x 17" is good
  • A12:  23" x 17" is good
  • A13:  23" x 16.5" is good
  • A14:  23" x 17" is good

The now-corrected dimensions above are entirely accurate and verified.  If you print templates, adjusting scale as necessary, using these corrected dimensions you will have perfect templates.  If your reference checks are off at all, it means your prints are off; NOT the marks themselves.

What to do if you've already built something

Most of the templates are accurate, and there's no cause for alarm in those areas.  However...

Canard (the 'GU' canard)

If you have already built your canard with the A2 templates you must destroy your canard and either find plans for the Roncz canard or wait for the next Open-EZ update.  If you've gotten this far you should know you would prefer the Roncz canard versus the GU canard anyway (and hopefully never built the canard).

Main Wing

If you have already built your main wing with the A10 templates you may have seen butt-joint surfaces off ~1/8" along a straight-edge.  This can be addressed as part of the standard wing glassing, filling, smoothing, and finishing operations.  Regardless, I would wait for the updated Open-EZ templates to compare against before you consider flying.

Your responsibility as a distributor of 'Open-EZ Rev 5' template files

The Revision 5 templates have not been available from the Canard Zone since January 26, 2010, but several web sites and other sources have since made these templates available (even before then).  If you manage one of these web sites or have downloaded the template files and shared with others, it is your responsibility to notify everyone who has or will have downloaded the template files of this information.  If you know of one of these web sites or download locations please pass along and share a link to this post.

Next Steps

Plans and efforts are already underway for an update to the Open-EZ templates, with a much improved technique for ensuring accurate analog AND digital template versions.  Understand that simply because someone may have templates or drawings that are "in CAD" does not necessarily make them more accurate than something hand-drawn on paper.  The concern is twofold:  1) what source was used to serve as the CAD reference (was the source accurate?), and 2) how exactly were the templates (dimensions) translated from analog to digital?  In the case of the Open-EZ templates, several original plans were utilized (at least 4 different complete original sets) to determine and set accurate reference dimensions and marks.  The Open-EZ templates are precise to <1/64" relative to the templates that were inspected.

Please be careful.  If in doubt, stop and get help, and by all means feel free to share your situation here.

Sincerely,
Jon

This post has been promoted to an article

 

 

Edited by Jon Matcho
Made red correction text even more clear (Ary Glantz's workaround is flawed and not required if one just follows the corrected measurements).

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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  • 5 weeks later...
On 11/9/2014 at 10:43 PM, magnum said:

FYI, this site has the plans for download    ( http://www.aryjglantz.com/p/documents.html?m=0) As far as I can tell with a quick look, its the same as the  terf CD. Its a good info site and he is doing a detailed build.

Tom

Thanks, I already have the plans I'm just trying to figure out what size paper to put them on for template use. I agree, Ary's site is very good. It's actually what motivated me to try this.

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Randy, if you open any PDF file using Adobe PDF Reader, you can then select the File > Properties menu where you will see the original page size.

The plans are not actually (at present) part of the Open-EZ project, but the paper size in the TERF plans is 14.5" x 8.5".  The original paper size of ALL plans shipped from RAF (as well as the Cozy plans) is 11" x 17".

Regardless, I would not trust any full-size drawings within the plans pages by simply scaling to 11x17 because:  

a) the original TERF scans may have reduced/enlarged sizes by a fraction, which is likely since the goal was not to reproduce any full-size drawings.

b) scaling to 11x17 will multiply any errors

c) there were never any verifiable reference marks

Still, you should be able to figure it out.  Is there a particular drawing that you see poses a problem?

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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Well yeah, look at all the parts for the various trim control pieces and the parts for the nose gear. Those are complex shapes. If they were square I might be able to loft them up but the curves kind of throw my pea-brain for a loop. If they were to scale I could trace them onto the flat metal plates. I'm not a fabricator I'm not sure how to get them accurately depicted onto the parts for cutting. I guess I'm missing some simple trick that all you guys know ?

Edited by 787Guy
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On 11/10/2014 at 2:23 PM, 787Guy said:

I'm not a fabricator I'm not sure how to get them accurately depicted onto the parts for cutting.

Most people buy the Cozygirrl parts.

http://cozygirrrl.com/aircraftparts.htm

Many of them are not to hard to make if you have the shop but it's time or money, take your choice. Shipping and hazardous fees are killers the days. Best to order all the materials at once from Spruce or Wicks.

I have found the biggest drag on building is waiting on parts or delaying something in order to make a larger order. A project really moves along quickly when you have everything.

-Kent
Cozy IV N13AM-750 hrs, Long-EZ-85 hrs and sold

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On 11/10/2014 at 2:23 PM, 787Guy said:

I guess I'm missing some simple trick that all you guys know ?

No, but you are experiencing the standard pain and suffering that many others have also had to get through. Also known as "paying your dues" I suppose.

Quote

Well yeah, look at all the parts for the various trim control pieces and the parts for the nose gear. Those are complex shapes.

Page numbers please (17-1 and 13-1 in this case). Most all metal parts were available as aftermarket parts way back (in the 1980s) with the exception being to build them yourself. Some choose to, which is entirely fine, but other options exist today for those that recognize "I'm not a fabricator". Consider supporting the community and buying them from a canard vendor.  For the nose gear, have you forgotten your Updated Suppliers List post? Nobody puts manual nose gears in new builds anymore. 

If you're still intent on having a manual nose gear retract system, you can take pages 13-1 to 13-3 to a machinist, with all parts and stock metal required (or have the machinist supply), and get parts made. If you do not see an obvious answer in a drawing, look elsewhere in the plans and you often find clarification or the detail you're looking for.  I expect you'll spend more than what an electric system and related parts would cost.

These are good questions, but I've found the situation is typical with plans-built aircraft in general.

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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Jon,

Oh boy - I'm not even talking about the manual gear parts I'm talking about little things like NG15A, NG3 and the nose wheel fork ( which I believe is a cast part) cozy girls don't seem to have those bits and I don't see anyone that does.

I'm just trying to make sure where to get things before I start the project. That's why I enquired about the suppliers list several posts ago. I'm not sure but I don't think a machinist can fabricate something very well without knowing the angle and radius measurements but I could be wrong - and in this case I hope I am.

Many of the individuals on the suppliers list are gone as well hence my frustration - I am ALL for as much prefabricated stuff as possible too.

Randy

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Nose gear forks here, see NG401B

http://www.eznoselift.com/index.php/price-list

The only part that can't be bought AFAIK, is the manual nose gear mechanism but it wouldn't be hard to fabricate. The Girrrls sell the large gear. Otherwise, they come up as people convert to the electric nose lifts

-Kent
Cozy IV N13AM-750 hrs, Long-EZ-85 hrs and sold

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On 11/10/2014 at 4:29 PM, 787Guy said:

Oh boy - I'm not even talking about the manual gear parts I'm talking about little things like NG15A, NG3 and the nose wheel fork ( which I believe is a cast part) cozy girls don't seem to have those bits and I don't see anyone that does.

Since Kent already gave you the link twice to where you can buy those parts today (first time in that other thread), you should buy them 🙂 I'll only add that you could produce a machined version of a cast part if you needed (or wanted) to.

Quote

I'm just trying to make sure where to get things before I start the project.

I certainly understand. It's a realistic concern when key parts are dependent on few individuals.

Quote

That's why I enquired about the suppliers list several posts ago. I'm not sure but I don't think a machinist can fabricate something very well without knowing the angle and radius measurements but I could be wrong - and in this case I hope I am.

Even in the absence of certain measurements, parts could be built if enough hints were given and the overall purpose described well enough. You will be impressed at how resourceful you will become. You'll also be able to keep your eye on items coming up for sale in various places.

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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Here's an example of a worm gear from one of my favorite "suppliers", McMaster-Carr (no idea which one would work for the manual gear, but you could figure it out after Googling for a weekend, etc. ;-)

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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On 11/11/2014 at 2:27 AM, 787Guy said:

Ok thanks for all that but unfortunately cozy girls does not supply those parts...

Are you talking about the trim system parts? Those are flat and very easy to make, relatively speaking. You could make them yourself with a bandsaw and a drill press or have someone else do them. You may also want to (should?) install an electric trim system versus the manual jiggery.

Several options exist on builder's web sites and from vendors such as (more available, not endorsing or in any order here):

At the time of this post all required parts are available for purchase or can be easily made for those with a will, a way, or money.  :)

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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It would appear that a few prospective builders have lost sight of the fact that the LongEZ is a plans built aircraft and that it is not a kit with every conceivable nut an bolt packaged in the shipping crate.

What complicates the situation is that plans are no longer available from RAF, thus builders are forced into the role of not only researcher, but "designer" to a lesser extent. 

During the plans preparation stage, there is a definite learning curve, or what has been described by Jon as "paying your dues." 

The OpenEZ plans, IMHO, should contain the disclaimer, "Some research and verification required."   :)

 

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Good points, and I give credit to those that have managed to break through the initial barrier -- it is perhaps harder than it ever was.

It's worth taking a moment to acknowledge how hard this must appear at first glance.  Even now I stop and think, "What if the (fill in the blank for a hard-to-get or make part) was no longer available?" and don't always come up with a good answer.  For example, nose gear bow, main gear bow, nose lifts, Cozy Girrrl parts, and then some.  In addition to knowing that the lack of a true factory exists (what would Aircraft Spruce do to secure ongoing Cozy/Long-EZ main/nose gear bow production, for example?) and the difficulty in identifying the proper approach to building anyway, I'm sure it's daunting to most prospective builders to the point of preventing building at all. 

To that end everyone needs to exercise some patience while the Open-EZ "plans" are updated to address this issue.  In the meantime your disclaimer certainly applies!

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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Another aspect from reading through this thread is that you can over think it also. Nowadays, there are many excellent sites, builders and solo info sites that explain almost everything that is done to build one in detail. All of them explain what parts they are using and why they came to that decision. Lots of detailed pics to go along with all of it. Also, not to be left out is the fact that everyone will go out of their way to help and some will make a part for you if they have done it for themselves.

   As was eluded to previously, a lot of stuff comes up for sale and can be had for really good prices....... Don't over think your way out of a fun project. (YOUR DREAM).

Tom

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"Time flys when your building"

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On 11/11/2014 at 6:55 AM, Jon Matcho said:

Are you talking about the trim system parts? Those are flat and very easy to make, relatively speaking. You could make them yourself with a bandsaw and a drill press or have someone else do them. You may also want to (should?) install an electric trim system versus the manual jiggery.

Several options exist on builder's web sites and from vendors such as (more available, not endorsing or in any order here):

At the time of this post all required parts are available for purchase or can be easily made for those with a will, a way, or money.  :)

Kind of funny you should mention that part about the bandsaw Jon. That was the whole purpose of my initial post. In looking at several of the drawings a couple days ago I pictured myself just tracing the scale patterns right onto the metal and cutting them out. Since finding out they are not to scale I'm not really sure how I would do it since curves and complex shapes are involved.

The part I was referring to that Cozy Girls doesn't have are the various metal pieces that attach to the nose gear strut. I intend to use electric trim for pitch not sure about roll.

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On 11/11/2014 at 10:40 PM, 787Guy said:

In looking at several of the drawings a couple days ago I pictured myself just tracing the scale patterns right onto the metal and cutting them out.

That is a workable approach for several items, provided they're close enough to scale (or indicate "FULL SIZE"). Granted, it would be nice to have drawings with full dimensions and mechanical detail, but you don't and that wasn't the general purpose of the drawings within the plans.

Quote

Since finding out they are not to scale I'm not really sure how I would do it since curves and complex shapes are involved.

Perhaps I steered you too far away from the in-plans diagrams. What I meant is that you need to determine the sizes required yourself. If a drawing shows a measurement -- use that measurement as opposed to assuming it is full-size (consider everything NOT to be full-size by default). Occasionally you will see "FULL SIZE" written, and if you print 11x17 that particular drawing will be close enough.

Quote

The part I was referring to that Cozy Girls doesn't have are the various metal pieces that attach to the nose gear strut.

I do not understand how this is still a question (you actually didn't ask any questions in your last post, although it seems you have one). Search in this topic and the Updated Suppliers List topic for all references to www.eznoselift.com. The nose gear parts you're talking about are available there.

Quote

I intend to use electric trim for pitch not sure about roll.

The same can be done for the ailerons, and you will find out how yourself as hundreds (thousands?) of others have done so already. You'll be able to pick the best design available. However, you do not actually need to concern yourself with this now (there are many hours of build work before anything metal is actually required) as your far away from being able to setup trim for anything right now.

If you make a leap of faith that "all the parts you need are available today", and that options will always exist and be shared by the canard-building community at large to keep these planes going, you can move on.

Here you go: http://www.aircraftspruce.com/catalog/cmpages/practicekit.php

Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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On 11/11/2014 at 10:40 PM, 787Guy said:

Kind of funny you should mention that part about the bandsaw Jon. That was the whole purpose of my initial post. In looking at several of the drawings a couple days ago I pictured myself just tracing the scale patterns right onto the metal and cutting them out. Since finding out they are not to scale I'm not really sure how I would do it since curves and complex shapes are involved.

The part I was referring to that Cozy Girls doesn't have are the various metal pieces that attach to the nose gear strut. I intend to use electric trim for pitch not sure about roll.

When you're ready for the exact measurements/full size drawings of the metal parts mentioned, I'm positive you'll find a member such as myself who's only too happy to oblige with a scan or exact dimensions.

It's not an understatement to say that there's more than enough work in the research/creating CAD drawings stage to keep you fully occupied for months.

If you have not already visited this website, here's a builder who's a bit further ahead of where you are at the present moment, 787.   He's another  OpenEZier ...  http://www.aryjglantz.com/p/blog-page.html?m=0

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Yes, it was Ary's Youtube videos that got me hooked in the first place. I guess I will try and ask him where he sourced his parts. Because as was mentioned earlier it goes better if you have the stuff you need instead of waiting around for it.

On a separate note my CFII is still current - if anyone needs a BFR or instrument currency in a Canard type aircraft we could sure work a deal !

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On 11/12/2014 at 7:36 PM, 787Guy said:

On a separate note my CFII is still current - if anyone needs a BFR or instrument currency in a Canard type aircraft we could sure work a deal !

Where are you?

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  • 3 months later...

I'm building a Long-EZ that was picked up with just the fuselage and canard built. All logs were there with fantastic documentation but no templates. I used the wing templates from the fifth edition of open-EZ drawings.  :sad: My second wing is close to finished, so I'm just going to keep moving on it, and I'll figure the rest out later.

I'll keep checking back here. I'd like to if anybody made the same mistake and how it's working out.

At times like these, I wish I could just design a plane instead of having to make due with an old design.

Thanks,

Connor

www.notsoez891.blogspot.com

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On 2/24/2015 at 9:59 AM, notsoez891 said:

I'll keep checking back here. I'd like to if anybody made the same mistake and how it's working out.

What's the size and nature of your "mistake"?   I gather that your wings are not cut correctly.

I can say from experience that some errors don't matter much.  On my Cozy, I built the strake leading edge 1" higher than plans.  In the pic, maybe you can see where the strake L.E. fairs down to match the wing at the added foam piece just inboard of the joint.  AFAICT, it doesn't make much difference in flying qualities as long as both strakes are the same.

OTOH, mounting the winglets with different incidences on my EZ made a big (bad) difference.

post-126542-0-25564800-1424793738_thumb.png

-Kent
Cozy IV N13AM-750 hrs, Long-EZ-85 hrs and sold

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  • 1 year later...

Hello everyone, just a few things about the Open-EZ:

  1. There continues to be a trickle of confusion in the questions I receive about the correct dimensions called out in the first post of this thread.  It's actually quite simple:
    1. Print the drawings once.
    2. Update the measurements according to the first post in this thread for drawings A2, A7 and A10.
    3. Verify measurements on all drawings according to the now-accurate dimension marks on the outside edge.  If you're more than 1/8" off at this point your printer is off for every print.
    4. Chances are "that's it".  You can play with scaling (printing to 101% or 99%, etc., as you see fit), or just measure and/or cut foam parts inside or out of the drawings.
  2. Open-EZ Revision 6 drawings (the fixes) will be published and available for download here in January 2017 2018.
  3. Open-EZ Revision 7 drawings (cleaned and with enhanced dimensional verification markings) will be:
    1. Available for download here ASAP in 2018.
    2. Also made available through a "print-on-demand" service for those wanting verified and checked drawings (without all of this anxiety in this thread).

Just wanted to share... 'tis the season!

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Jon Matcho :busy:
Builder & Canard Zone Admin
Now:  Rebuilding Quickie Tri-Q200 N479E
Next:  Resume building a Cozy Mark IV

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