Recent Posts

41

Chuck's XL in Indiana / Re: A little progress XL H-58

« Last post by Chuck in Indiana on May 14, 2025, 02:16:46 PM »

Thanks for the kind words. The toe brakes are fine. Not needed, really..I've never had to drag a downwind brake on rollout. They *are* good for turning around on the runway, but that's about all IMHO. I had a flying Jones last week but it was blowing directly across the runway, actually worse than I thought. When I came in, the little weather station was saying 10-12. It handles crosswinds well.. after all there's no fuselage back there.

42

Chuck's XL in Indiana / Re: A little progress XL H-58

« Last post by Rick on May 14, 2025, 07:45:37 AM »

Dear Chuck,

As a former cnc machinist - 1970's & 80's, I really appreciate that you shared your skills in fabricating your LEXL bullet, just terrific work. So when I got to your post on page 22 of your build, Reply #320 - rudder petals and "(hopefully) toe brakes" you had my attention!!!

I am a newbie builder - LEU and low-time Cub flier, but, I have 25 years experience with a 4-wheel Kubota on my hillside hobby vineyard. Operating askew in very tight quarters and sometimes slippery conditions having to drag a left or right brake (with feet) to avoid slamming into posts or vines has become second nature. Not something I want to do with double hand levers mounted on the control stick while steering an airplane. Not to mention that my local grass airstrip is also on a hillside.

SO . . . after flying for awhile with Bullet, how are the toe brakes working out? I also watched your video "Bullet walk-around" but no mention of toe brakes.

43

Builders logs / Re: Robert's LE (Original Design) Build Log - Oregon USA

« Last post by Tom Emery on May 13, 2025, 03:58:37 PM »

Would anyone on here happen to have the Dxf files for the nose ribs and the aileron rib? I lost the stylus for my digitizer and am lost without it.
Thanks in advance.
Tom Emery

44

Double Seaters / Re: First post, and sacrilege already

« Last post by BobbyBreadwinner on May 13, 2025, 02:16:14 PM »

I'm wondering why go through the trouble to precicely cope the tubes if you're assembling with gussets anyway? 

That has been discussed by the coffee group at our EAA: One could argue that the copes become a secondary load path under compression, or they straddle the tube preventing movement side to side, or if you needed to you could add epoxy to the joint, or it is a starting point for a welded structure, or at the very least if you have the something in the wrong place it will definitely not go together. Final answer: it just looks cooler.

I have used this system to create assemblies that were welded (larger aluminum tube assemblies, engine mounts, non-gusseted assemblies, etc.) so the copes were necessary. However, back to the original topic...

It is kind of inefficient to use a bunch of time to accurately cope small tubing. In my humble opinion, 1/2 inch is the tipping point. Anything smaller and you can just straight cut at the correct angle and fill when welding. At 1/2 inch you need a little bit of cope, but close is good enough. At 5/8 inch tube your TIG welds start to look like ugly MIG welds if you have sloppy copes. At 3/4 and up, coping accurately is necessary and really shows in your final product. Almost the whole fuselage of the Legal Eagle is in the 1/2 to 5/8 inch neighborhood. So whether you CNC cut or hand cut you end up with about the same aircraft. I personally would rather CNC cut tubes because it makes welding a bit easier: I am great at cutting and grinding, I am not so great at TIG welding tiny objects (thank you old eyes and shaky hands).


I hope this helps,

Robert

45

Double Seaters / Re: First post, and sacrilege already

« Last post by thseng on May 13, 2025, 01:13:54 PM »

I am going out on a limb here to say that I am likely the only one who can answer your question with any experience

I'm forced to agree. Thanks for posting that, very interesting. 

Off topic, I'm wondering why go through the trouble to precicely cope the tubes if you're assembling with gussets anyway? 

46

Builders logs / Re: Pappy's LEXL Build in Texas

« Last post by pappyadkins on May 12, 2025, 10:46:02 AM »

No offense ever Chuck! You are correct about any bolt that can pivot... I think I've mentioned that before even... I'm waiting on hardware order as we speak... Thanks for looking out for us - Thanks for all your input in the community for sure!!!

47

Double Seaters / Re: First post, and sacrilege already

« Last post by BobbyBreadwinner on May 12, 2025, 09:03:31 AM »

Charlie,

I am going out on a limb here to say that I am likely the only one who can answer your question with any experience: I have a CNC router, with a tube cutter, of which I use to cut aircraft tubes. I have written specialized software to perform the coping calculations which result in CNC files. And yes, I am the guy who has cut the tubes for the current builds of Barnaby Wainfan's Facetmobile. Those details are here:

https://worktablecnc.us/projects/facetmobile.html

I have also built a Legal Eagle the traditional way: With two angle grinders, one with a cut-off wheel and one with a grinding wheel, I have cut, ground, ground, ground, and ground until the tubes are all coped perfectly together. I did the welding using TIG, and any gaps left I had to bridge with extra filler. Those details are here:

https://worktablecnc.us/projects/legaleagle.html

---

If I had to build a second Legal Eagle...

I would probably use the CNC. It would take more time. I am a builder, that does not bother me. I enjoy building, solving problems, being creative, and ending up with a product which reflects the very best I can do.

If I needed to get it done quickly...

I would cut it by hand just like I did it before, and then blast it with a MIG welder.

---


* There is space enough in this community that either way is the correct way. You do you. *


---

I do have a few additional comments:

+ If you already have a RV-7, then you already have an aircraft with a second seat that most of the time will be empty. If you are looking for a simple after-dinner flying machine then please reconsider the single-seat Legal Eagle. It will be an ultralight, no registration, lots of flying examples, easy-peasy. I have a lot of friends which are RV builders/pilots. A common mantra with those guys is More-Is-Better. Legal Eagle = Less-Is-Better.

+ I previously looked at the VR3 Engineering requirements (for the rest of the group VR3 Engineering is a Canadian company which provides CNC cut tube kits, and they do not exclude aircraft). You can either simply buy one of their kits, or you can send them your own files. However, creating your own files is no small task: You have to take every tube, drawn and coped in 3D, then slit the 3D tube, flatten it, and provide a 2D pattern. I use CAD for a living; this is a mountain of work. Whoever did all of this originally for the Legal Eagle patterns at VR3 deserves a big hug.

+ No, I do not provide CNC services with my router. I only helped out a few of the guys at my local EAA chapter, and Barnaby is now one of them. The time I have spent on their projects I could have completed another aircraft of my own. I have a list of projects I would like to do which exceeds my lifetime, and becoming a tube kit manufacturer is not one of them.


Respectfully,

Robert (BobbyBreadwinner)
Oregon, USA

https://worktablecnc.us

48

Builders logs / Re: Pappy's LEXL Build in Texas

« Last post by Chuck in Indiana on May 10, 2025, 02:39:32 PM »

I also made a delrin spacer to keep anything from interfering and not having to bend the arm. Here's the finished assembly.

49

Builders logs / Re: Pappy's LEXL Build in Texas

« Last post by Chuck in Indiana on May 10, 2025, 02:33:15 PM »

Pappy, certainly no offense intended, but on your pivot bolts for the aileron linkage, you have a standard AN365 lock nut. Where a castellated nut and cotter pin is required is "Subject to rotation." That bolt is able to rotate, and needs to be cotter pinned like so..

50

Off Topics and General Interest / 3D printed fairings

« Last post by Brock on May 09, 2025, 09:59:49 PM »

This is a little project that I have been working on for a Sportsman.  It is coming to completion and I got to thinking it might be fun to print a few fairing for the LE.  Removable and not required for flight, of course.  Here are some videos to tease the idea.