front spar height

[Rick]

Hi Guys,

I'm building the original LE Ultralight, and from reading the Eagler's Nest posts it seems the ribs and spars are the same on the LE XL also. I just finished all my ribs and am working on the spar frames. Completed a rear spar and a front spar (lucky no spar webs added yet).

However, on a mockup with a rib prior to proceeding, I noticed an issue with front spar height. I have not found anything searching on Eagler's Nest about this. Am I missing something here or does anyone have different front spar heights on their plans. (Oh, and yes, after the fact I did notice the stamp on the bottom of the wing spar drawing) a gotcha moment?

I'm working off of plans 9/2024 as a web download from Leonard's Legal Eagle website and the full size rib drawing mailed 9/2024. Rib drawing shows the rib height of 7.25" high. The plans call for in two locations (see attached) a dimension of 6 7/8"
So to match the ribs it seems the front spar should be 7 3/16” ?, (Rib 7 1/4” - 1/16” 2 layers of 8 mm PLY)

I'm a first time plane builder with general carpentry skills, however as a young man -10 years as machinist/welder. Going from the Titebond III website, heating the glue with an iron soften the glue enough to wiggle the verticals free.

Now what? Replace all the verticals or can I just glue in spacers to make up the difference? see attached. What is proper?

Thank you very much!

[Kamcoman77]

If your rib is 7-1/4" tall at the front, then 7-1/4" - 1/16" is correct for spar height where it meets the rib. No spacers, please. Make new verticals. Seems like a lot of builders have slightly different dimensions.

[Rick]

Kamcoman77,

Thank your the quick response! Will do the new verticals tomorrow (I kinda new that).

I just started on the build in 2025 and not sure of the protocol here, when I come across issues with dimensions is it enough to post it on the forum or should I notify someone else (designer etc.)
– Just trying to do the right thing.

Thanks again,
Rick

[Kamcoman77]

You can usually get quick answers (and some opinions) here and on the Legal Eagle Facebook page. Leonard will answer questions if you call him. In many cases, using the Search feature here and Facebook will give the answers.

[Rick]

Good advice. I never joined Facebook always thought of it as a little evil . . . but. Do you feel Facebook has valuable info not presented here on Eagler's Nest! If so perhaps I'll give it a go.

Thank you Kamcoman77,
Rick

[Kamcoman77]

Yes

[Rick]

I'll give it a shot. Thank you.

[DA Miller]

Rick , you're not the first to get caught on this.  I and others got trapped by thinking that the full size rib drawing would be the correct dimension to match the spar height. These LE drawings are more like sketches than engineering plans. The rule in building a Legal Eagle is to cross check every dimension and its intersection with every other part that it contacts don't take anything for granted; check it out.  That being said many of us have carried on after being bitten by the FSWD. Learn how to use the search function at the center of top of page. E.g. Search tail feathers before starting to build your tail feathers you will find much good info. Keep plugging and ask the forum if you need help.
DA

[Rick]

DA,

Viewing Chuck's build and the ADCO video's has been most helpful so far working through the little issues with the tail section and fuselage, and doing just as you suggest, using search. But this time, after a long building pause, and getting nada from the search "front spar height" no matter the many variations, I proceeded . . . and got caught. Next time, I shall take your advice and just ask for help – no easy feat.

Also, I was pleasantly surprised how quickly the forum response came from the post, you folks are great.

Thanks for your encouragement!
Rick

P.S. Perhaps Leonard's great plan is teaching us all to be humble? ;-)

[Rick]

Since I have to rebuilt the front spar, thought I should confirm my assumption about the placing of the verticals to achieve the 139" width.– attached are the originals and the assumption. Not going to mention how long it took to decide ;-)

Thank you!

[pappyadkins]

Well, as you know, I'm working on an XL - maybe someone else can chime in here, but the last bay (wing tip) is longer than the others - measurements starts with the inboard side (the first double rib doesn't count in the over all length - if that makes sense) so you have a rib, then 1.5" have rib#2, then 13.5" the 3rd rib, then 15" the 4th, then 15" the 5th & so on...  If that's not helping then I'll shut up... lol  Again, not sure, but that's how I read the plans as you posted...  If you build as you modified in 2nd pix, your struts will be 1.5" farther outboard than designed... doubt that'd hurt; but just know it'll be different...

[Rick]

Pappy,
It does make sense, that's how I first read it. Then while laying out on the table that (65") diagonal strut brace dimension looked out of proportion from the 6th vertical (L-> R), 4x15" spacing = 60". Attached is that first assumption, with last rib spacing (L->R) of 17".

I don't like the idea of changing the strut location. What da ya think?
Thank you!
Rick

[Chuck in Indiana]

I don't like the idea of changing the strut location. What da ya think?

I don't much care for it either.  Probably wouldn't hurt anything, though..up to you. You have to be *very* careful changing anything because it might affect something later on.

[Rick]

You have to be *very* careful changing anything because it might affect something later on.

Chuck,

That's why I've been struggling with this, wings kinda important.

I just created a  drawing TO SCALE in the only 2-D application I  own (Adobe Illustrator)

• Wing length: 139"
• Strut Brace location per plans: 65" from inboard, on 30.5˚ angle
• 15" between each bay, with 2" from inboard/outboard ends (+/-.125")

This looks proportional to Leonard's Plans . . . to my eye. yours  ? ? ?

Rick

[Chuck in Indiana]

I gave my xl plans to a kid that *thinks* he would like to build one  so I can't say what differences there are. I like the looks of the top one, though. It's kind of weird to dimension it that way. I would give the dimension from the root to the hole in the fitting if it were me.