Roll call: Open-EZ builders?

[Jon Matcho]

Since today is the 7-month anniversary of the Open-EZ, what better time than now to ask a few questions:

 

a) Anyone building an Open-EZ?

b) Anyone planning/intending to?

c) Do you think we should continue?

d) Any ideas for what to add?

 

The biggest request is for full-sized drawings. After that, the suggestion box is open and waiting for your feedback.

 

Go ahead... a penny for your thoughts.

[Big Steve]

This Might sound crazy to some but after I finish this cozy I am thinking of building an open ez if the information is still around. I guess I just like the "Build" STeve

[aadamson]

I've collected all the build instruction *stuff* and once I get my Legacy finished. I'll most likely start one as well. Would really like to see those full size drawings.

 

Alan

[dpaton]

Go ahead... a penny for your thoughts.

I'm collecting my pennies, but more than likely they'll end up paying for Cozy plans now instead of OpenEZ parts. Part of it is practical...going cross country with 2 people in an EZ, you have less baggage capacity than in a Cozy, but most of it is that my GIB hates tandem flight, she gets terribly airsick back there. Side by side it's no problem at all, even in unusual attitudes. Neither of us can explain it, but that's the way it is. Yes, the EZ is a more efficient cruiser, but if I can't cruise with my passenger, then what's the point?

 

I'm still working (slowly) on getting the templates unified, but I'm somewhat hampered right now. It's come to my attention that the ones that we have may be less than perfect, and there may be better examples out there. I'm working to get those examples into my hands for comparision and review, to make sure the stuff I produce is as good as it can be.

 

Updates as they happen.

 

-dave

[Jon Matcho]

I'm collecting my pennies, but more than likely they'll end up paying for Cozy plans now instead of OpenEZ parts.

I certainly won't hold that against you!

 

I'm still working (slowly) on getting the templates unified, but I'm somewhat hampered right now.

Good to hear. I was thinking of starting up the same effort -- maybe we can divide and conquer?

 

It's come to my attention that the ones that we have may be less than perfect, and there may be better examples out there.

I think someone is feeding you a line of BS. The digitized versions were compared against:

• originals located in New York (now sold), and
• my copies that came from Australia.

Both were found to contain the same "defect", which points back to the original printing of the Long-EZ plans. This "defect" would affect many holders/builders/flyers of original Long-EZ plans.

 

I'm working to get those examples into my hands for comparision and review, to make sure the stuff I produce is as good as it can be.

It is, of course, possible that multiple batches of plans were printed at RAF with various results. But was it the master that had the defect, or the resulting prints? I too am curious about this, but still hold firm that this is par for the course with 1980s technology and amounts to a non-event in the life of an EZ builder.

[dpaton]

It is, of course, possible that multiple batches of plans were printed at RAF with various results. But was it the master that had the defect, or the resulting prints? I too am curious about this, but still hold firm that this is par for the course with 1980s technology and amounts to a non-event in the life of an EZ builder.

I only have one data point right now, and I couldn't secure the sheets I saw for scanning, but I did hold in my hands a set of assembled original templates that had no distortion whatsoever. Every single line on every single sheet lined up perfectly, all circles were circles, and the quick measurements I was able to do showed none of the compression and skewing on the existing OpenEZ drawings. I'm working very hard to get those drawings back into my hands, and I'm following leads on another set reputed to be in equally good condition. I was very surprised when I saw them, as I was under the impression that all copies were the same. I was rather excited as well, as perfect drawings will allow the computerized tracing of the templates, getting us close to our goal of a CADd OpenEZ.

 

I'm quite certain that there were multiple printings of the EZ drawings over the years, and that the masters did not have the distortion present in the existing electronic files.

 

The real mystery is what happened to create the two branches of the templates?

 

-dave

[Big Steve]

I built a Longeze back in the early 80's I do not remeber having any kind of mismatch with any of my drawings. The Plane flew great and I am still missing it. I wonder if it that big of a deal having these lines match up perfectly. There are a lot of Longeze's flying out there and I bet their:confused: lines did not match up perfectly. Just my .02 STeve

[dpaton]

There are a lot of Longeze's flying out there and I bet their:confused: lines did not match up perfectly. Just my .02 STeve

I freely admit that I'm being anal about it, but when I did the initial fit of the templates in my computer, I was off by close to 0.5" in some places. I'll tolerate 1/6-1/8" here and there, but 1/4" is bad and 1/2" is unacceptable to me. The out of roundness of some of the gauges on the IP and some skewing of the firewall templates really spooked me badly, in that such things, if present elsewhere, would build a plane that would never be straight.

 

Yes, it may be a bit obsessive, but I want to make sure that anything I contribute is as close to infallible as possible, since it'll be more than just my butt riding on it.

[Jon Matcho]

My Cozy Mark IV, AeroCanard FG, and full-sized Cozy drawings have the same issues.

 

...I did hold in my hands a set of assembled original templates that had no distortion whatsoever. Every single line on every single sheet lined up perfectly, all circles were circles, and the quick measurements I was able to do showed none of the compression and skewing on the existing OpenEZ drawings.

Well then, that sounds a touch more definite than "there may be".

 

I'm working very hard to get those drawings back into my hands, and I'm following leads on another set reputed to be in equally good condition.

That's a better route to pursue than doing it "down and dirty".

 

I'm quite certain that there were multiple printings of the EZ drawings over the years, and that the masters did not have the distortion present in the existing electronic files.

Given what you've seen, that is likely.

 

The real mystery is what happened to create the two branches of the templates?

Not really a mystery. Print run #1 produced "perfect" versions, while print run #n used a printer/copier with a bad feeding system.

 

Also, to put this in perspective, we're talking about line widths, 1/16ths, and at worst, 1/8ths of a difference. I can tell you that anyone who thinks that 1/8th of a difference in airfoil drawings is going to have a major impact on adverse performance of an EZ has simply not cut templates, hot wired foam, smoothed, glassed, and finished a wing. There are MANY opportunities to introduce at LEAST this much error in the process. For all I know, you might end up with a better airfoil than what is actually specified.

 

Regardless, I too would like to have something based as close to the original master as possible, without any errors or defects whatsoever. My point is only that if I were into the build process (and I am with the Cozy -- the same issues are present and visible), I wouldn't hesitate to continue (since I already did).

[magnum]

Hey!

I'm building and kinda using the open ez plus my own changes I want. All the info is useful and it saves a lot of reasearch. Keep up the good work everyone!!!

[Jon Matcho]

Thanks for the feedback Steve and Magnum.

 

...but 1/4" is bad and 1/2" is unacceptable to me.

I agree.

 

The out of roundness of some of the gauges on the IP and some skewing of the firewall templates really spooked me badly, in that such things, if present elsewhere, would build a plane that would never be straight.

I could see spooked as well, but don't worry about any of this affecting whether you'll build a straight aircraft. There are many opportunities and checkpoints to verify straight and level. If you ensure that everything you do on both sides is symmetric, you'll build a fine aircraft. It's all about symmetry (and a bunch of other stuff ).

 

Yes, it may be a bit obsessive, but I want to make sure that anything I contribute is as close to infallible as possible, since it'll be more than just my butt riding on it.

We can only do our best, and it's really up to the builder to decide whether to fly or not.

 

This feedback is good!

[DowningHawk]

I'm still interested in building one. I printed the templates at Kinkos and have measuring discrepancies. The measuring tick marks on the page margins are often not to the scale they claim. A couple of them were 1" off, with others being within 1/8".... But when I put the the drawings together, everything fits just fine. Has anyone else had this problem? Were the tick marks added to the drawings or were they originally there? Kinkos printed them out all the same with no scaling. I am hesitant to start any actual construction with this uncertainty.

 

For those who have printed the drawings, did you measure all of the tick marks? Did they all come out perfectly?

 

 

Thanks,

Mike

[Jon Matcho]

The measuring tick marks on the page margins are often not to the scale they claim. A couple of them were 1" off, with others being within 1/8".... But when I put the the drawings together, everything fits just fine.

Sounds like printing is off in one axis.

 

Were the tick marks added to the drawings or were they originally there?

The tick marks were added to the original drawings prior to scanning. If they don't measure-up, the prints are unacceptable.

 

Kinkos printed them out all the same with no scaling.

Did you use the TIF files or the PDFs? The next version is NOT going to include the TIF files as PDFs are more portable.

 

I am hesitant to start any actual construction with this uncertainty.

Absolutely. If the tick marks do not measure up, then you cannot use them. 1/8" is not so bad, but anything over needs to be fixed.

[Jon Matcho]

A couple of them were 1" off, with others being within 1/8"

Some more thoughts on this. Have them print the PDFs, which contain embedded measurement information for the size of the paper (which you can see yourself when opening the PDF in Acrobat Reader). If their output is different than the PDF size, which it must be in order to be an entire 1" off, then they need to fix their method of output for you.

 

However, what might have happened is that you may have used the TIF files, which are not good for controlling dimensions. They will not be included in the next release.

 

Let me know if that helps.

[bigriverdubya]

I have the build manual for a long ez and an incomplete set of A1-A14 templates. With the Open EZ A1 - A14 templates I now have everything I need. I am planning on starting in the spring of 07.

[EZ AHAB]

Looks to me like the solution to all this dimensional accuracy stuff is to use a CAD format. Reproducing dimensional accuracy is what CAD is for, not PDF. Am I just stating the obvious or is there a good reason this hasn't been done. I've digitized portions of the plans myself but not all of them. I redesigned the lofting of the fuselage on my plane so I drew all new fuselage bulkheads anyway. It shouldn't be all that big of a deal to simply import the images into CAD and scale them appropriately. I've done this plenty of times to repoduce the hotwire templates. What I don't know is whether or not raster images are exported in dxf format for printing purposes. I'll investigate and see.

 

Also of note on the subject of dimensional accuracy is the fact that I measured the Roncz canard templates on my original plans I got from RAF. There are 2 that are simply mirror images of each other. They should be exactly the same length, right? They were about 1/10" off which I consider to be very significant since the whole chord length on the template is only about 10". That's a 1% difference even when comparing two original drawings printed at the same time on the same piece of paper! This could give you up to 1/2" of error over the 43" length of the largest wing template.

[dpaton]

Reproducing dimensional accuracy is what CAD is for, not PDF

I beg to differ. The import/export processs between CAD packages (since we must deal with the fact that not everyone uses the same thing) can introduuce just as many, if not more, scaling errors than a PDF, and iss a thing more succeptaable to humaan error than not. A PDF is a static document, allowing no adjustment without explicit scaling. It is tied to both a paper size and bitmap raster content, and given anything but the most byzantine print drivers or invasive print operator, will always come out the same size every time, given the same paper size in the print device. If we all had access to architectural print shops that can push a DXF out to a DesignJet with 0.05% scaling acuracy I'd be all for it, but since most folks only have a local Kinkos, PDF is the most reliable option.

 

Bitmap images like are used in the exiisting OpenEZ templates are exported as such, not as CAD vector data (DXF/true PostScript)

 

As for the template scaling errors, it's something I'm working on. Check a few posts back. There are larger errors than those in some templates. I'm trying to track down a set that doesn't have them so we can update ours and be closer to accurate.

[Jon Matcho]

Looks to me like the solution to all this dimensional accuracy stuff is to use a CAD format. Reproducing dimensional accuracy is what CAD is for, not PDF. Am I just stating the obvious or is there a good reason this hasn't been done.

You're misunderstanding the sole purpose of PDF -- portable document format. If anything can be expected to be printed accurately from one device to another, it's a PDF file. CAD files rely on the program under which they're loaded. Last I checked CAD files are NOT OPEN (the file format is defined and controlled by Autodesk). Even if it was open, you need to rely on the company implementing the format properly in their CAD product. Bottomline, no guarantees w/DWx file formats.

 

There are no guarantees with PDF, but considering that the sole purpose of the PDF format is to allow documents to be PORTABLE from one printer to the next, the PDF format is the best choice as far as I'm concerned. It's also why ALL the CAD software companies are supporting it.

 

The next version of the Open-EZ will be distributed in PDF format. If CAD files exist by then, great, but good luck bringing them to Kinkos and getting them to print accurately.

 

Also of note on the subject of dimensional accuracy is the fact that I measured the Roncz canard templates on my original plans I got from RAF. There are 2 that are simply mirror images of each other. They should be exactly the same length, right? They were about 1/10" off which I consider to be very significant since the whole chord length on the template is only about 10". That's a 1% difference even when comparing two original drawings printed at the same time on the same piece of paper! This could give you up to 1/2" of error over the 43" length of the largest wing template.

Your point is that the RAF ORIGINALS are OFF as well. I just verified my COPIES of the Roncz originals (mirrors @WL 19.8) to be off 1mm in one measurement (over approx 20cm). Would I care if I were building a Long-EZ? Absoultely not! I'd just average the two and use that to determine whether I cut inside or outside of the lines.

[EZ AHAB]

I understand the purpose of pdf very well. I'm just saying it's not exactly intended to reproduce scale drawings like CAD is. Maybe it works fine anyway, I've never tested it.

 

Also, I've never actually tried to get something printed at Kinkos that I needed to be dimensionally accurate so I can't speak to that. If I really needed quality full sized prints, I would try to find a place that does architectural drawings. I don't live in all that large a city and there's one here so I would assume they aren't that hard to find??? Anyway, I usually just print everything at home on my inkjet printer on legal sized paper and then paste the pages together. That way I have full control over the dimensional accuracy of my prints. If I properly calibrate my printer it works fine. 1 inch equals 1 inch. I also have an old HP pen plotter that does an excellent job too but will only print vector images, not pdf or bmp. I got it on ebay delivered for $30.

 

As far as CAD losing accuracy between packages; again I only have one package that fulfills all my needs plus I always use dwg format, not dxf so I haven't had to deal with any of that. It just seems to me that it should work very well. Maybe I'm wrong. I do know that after I import images to CAD and get everything set up properly and then print them again, they line up perfectly with the originals.

[Jon Matcho]

I'm just saying it's not exactly intended to reproduce scale drawings like CAD is. Maybe it works fine anyway, I've never tested it.

I think you're wrong on this point. As I said, all the major CAD vendors have or are in development with add-on products to support PDF as a more readily transportable file format -- because it is a format designed to reproduce "ink on a paper" most accurately among disparate devices.

 

The problem with the CAD file formats is that there is NOT a standard file format (yet?) and therefore there MAY be inaccuracies when exporting from one program into another. With PDF this behavior would be considered a defect. In the case here where we're talking about the output being an entire 1" off, I suspect that is a printer calibration issue and not a PDF issue.

 

Also, I've never actually tried to get something printed at Kinkos that I needed to be dimensionally accurate so I can't speak to that. If I really needed quality full sized prints, I would try to find a place that does architectural drawings. I don't live in all that large a city and there's one here so I would assume they aren't that hard to find???

One of the goals of the Open-EZ project is to keep things simple and allow any builder the luxury of walking into a run-of-the-mill print shop (Kinkos for example) with a bunch of files and walk out w/accurate drawings economically. Locating a print shop equipped to print CAD files is at another level of complexity.

[Jon Matcho]

Also, I think it's a GOOD idea to get the drawings cleaned up, which likely means doing that using a CAD software. However, the universal output should still be PDF. If CAD files were available as well, that's bonus.

 

Taking a step back, and considering ONLY the drawings -- why do we want CAD? For me, it's so that the drawings would only look 'cleaner'. In the big picture, this is completely unnecessary as they're certainly good enough in their current pencil-based "analog" state. You can indeed build a plane with them, as several hundred builders have managed to do so before.

[gfulton]

I plan on building once the question of the templates is settled. I'll also need to TERF CD, and the garage cleaned out, but I'm getting there.

[Jon Matcho]

I plan on building once the question of the templates is settled.

As far as I am concerned, there are no issues "at large" beyond those that hundreds of EZ builders have already dealt with.

 

However, we do have this issue:

 

I printed the templates at Kinkos and have measuring discrepancies. The measuring tick marks on the page margins are often not to the scale they claim. A couple of them were 1" off, with others being within 1/8".

What drawing is 1" off? Did you have the TIFFs or the PDFs printed? I will retest at my local Kinkos if you give me the info.

 

Speaking of Kinkos, the local shop by me recently converted their SOP for scanning to give customers PDF files instead of TIFF files. When I asked why, the person reminded me that the TIFF file is a raw file that is subject to the device it's being printed from whereas PDF prints consistently regardless of the device.

[ColinB]

back on topic

 

ill be building an open ez when spring comes

 

however im planning on taking on a few berkut esq changes and a few bits of my own

[Jon Matcho]

I plan on building once the question of the templates is settled.

I tried to settle this in another post.

 

I'll also need to TERF CD...

I have an extra TERF RAF Encyclopedia if you're interested. I'll put up here or on eBay shortly...

 

...and the garage cleaned out, but I'm getting there.

Ah yes, reality. Cleaning the garage out is a good thing. That's when I realized I was on a collision course with a junkyard...

 

ill be building an open ez when spring comes

Okay then, maybe should keep this project going.