Wayne,

Never noticed a problem. This is not a true I-Beam. It's a Millennium type of structure. Sort of. It does use strip ribs but you'll notice the start of the spar. It's built in the wing after the ribs are in.

It will also be partially sheeted.

 Hmm. Maybe I'm just thinking too hard about it.

No wonder your finish comes out heavy.   Look at all that metal in the paint.   

Tim,

Yea, that's why the white will probably end up just being white and any metallic will be in minimal trim. But the truth is, metallic paint isn't the culprit, it's putting on multiple coats. I will use a blocking coat and a very thin coat of white. In the mean time, I want to keep the weight down on the structure. And I have these cool new toys to try for the landing gear.

Some people claim to cover one or both sides of the balsa sheet with tissue/dope to strengthen the ribs or bulkheads, before cutting out the parts. Just a coat of clear on both sides would help quite a bit. Can't say I've ever stooped to such trickery, but it's not a bad idea. Watch the grain direction on the tissue, if you use it. Would .2 oz carbon mat work? I dunno, but an experiment with some scrap would tell the tale.  Steve

Some people claim to cover one or both sides of the balsa sheet with tissue/dope to strengthen the ribs or bulkheads, before cutting out the parts. Just a coat of clear on both sides would help quite a bit. Can't say I've ever stooped to such trickery, but it's not a bad idea. Watch the grain direction on the tissue, if you use it. Would .2 oz carbon mat work? I dunno, but an experiment with some scrap would tell the tale.  Steve

I'd want to weigh the result, and compare it to just using a bit heavier balsa.

It'd certainly keep the balsa from splitting, particularly if the tissue grain runs crossways to the balsa's grain.

CF may dull your knife blades extra-fast.

I've got an idea for the leadouts. WooHoo!

Here's a suggestion for what to do if your idea doesn't pan out.  Do not let it be said that I am not without suggestions when a technological problem presents itself.

Given that your plane is electric, with training this may even work for voice-activated, in-air adjustment.

G/day Randy
                   Just a quick question ,how do you get the true air foil shape on the rib lay out on the angle ribs? do you just cut the trailing edge off ribs like normal or do you have a secret in keeping the high point of rib in line? haha. just wondering as i got a plan here that i like to build and has a angle rib lay out. thanks
 Steve

I'll post some more pics in a few days. I want to thank Tim Wescott for some pictures that triggered the idea that led to my leadout configuration. While not really like Tim's idea, it certainly gave me the idea. Hope it works OK. It's done and seems to work really well. Guess we'll see.

The blocks are done and fit the fuse like a glove, so that's cool. Need to build gear mounts next then I can finish dropping the half ribs in and get the bottom sheeted, flip the wing over and do the other side. Pretty cool so far.

So, I'm plugging through. While not brilliant, I have been able to figure my way around some knotty problems. It's what makes this fun.

Wayne,

Weeee!!!!!!!!!!

Tim,

He, he.

What is the top picture?  Molds for fuselage pieces?

This old man can't figure out the middle pic. 

It does look like leadout slides, and he's adjusting from the bottom of the wing, like the ones that I schlopped onto the Gift Banshee I have.

If the wing is thin, and if those guides are buried well inboard of the tip, aren't there going to be problems if the plane rolls?  Even if it doesn't bang on corners, I would expect that in turbulent conditions you'd get quite a bit of roll.  I'd be worried about the actual exit point at the tip cracking out, or otherwise responding badly to having leadouts pushed up or down into it.

" I'd be worried about the actual exit point at the tip cracking out, or otherwise responding badly to having leadouts pushed up or down into it."

A lot of guys line the leadout tunnel in the tip with 1/64" plywood. Not saying that Randy does or doesn't do that.

John...We'll look forward to seeing you around this season also. Does that mean you'll be at NW Regionals at Eugene? Try to get Patrick to show. I intend to go, 'cause I have no plans to drive to Tennessee again next May! I'm trying to get Gary Gingerich to go also.  Steve

Tim,

I thought about that, too. The reason it's done this way is that I could really come up with an adjustment device that would work with the wing tip layout. Due to this being an electric, I was concerned about being able to get the leadouts far enough forward. That put the possibility that the leadouts would exit the leading edge into play. so I put in this device and have the path lined with 1/64" plywood. I've also reinforced the wing top and bottom to withstand a certain amount of torque that might happen if I hit the wind wrong and get some roll. The system is very free moving so I don't expect any problems, but you never know, I guess.

Oh, almost forgot. This whole thing will have a hatch over it so no, it won't be a turbulence device.

Charles,

It's a new design, but it's based on some other stuff I've done and a lot of listening to very good designers.

Tim,

As Justin Wilson said, I'm a safety man. I wear a belt AND suspenders.

Due to this being an electric, I was concerned about being able to get the leadouts far enough forward.

Electric-plane leadouts seem to want to be pretty far back, so leave some room there, too.   

OK, I'm machining the gear mounts. The stab is framed up. Just need to shape it. Should be able to finish up the gear tomorrow and get the stab done.

So, I machined gear mounts out of aluminum. They are pretty light (under a 1/4oz each for the whole assembly). Now I have to figure out how to attach them so they stay in the wing. I have an idea to lock them in so that they aren't dependent on glue to hold them in. The stab is done. I'll post some pictures in a couple of days.

 Um, just wondering, why aluminum?

What Tim said. Plus, you can drill and tap it for gear retention clips. Lot of work to machine out a lot of the material to keep the weight off, but in the end makes a nice piece.

Charles,

Primarily a bench top mill along with a ton of tooling. Nice as you can do a lot of stuff yourself. I'll take some pictures before I glue them in the wing.

more photos !!!

 

I second that 

Marcus

OK, this is tonight before I get started. Notice the hinge pockets in the stab training edge. The tips of the stab are just sitting there. I'll shape them once the stab is sheeted and the twin rudders are on. And the molded block flipped over is for Tim. The gear blocks are not finished, but you get the idea.

Marcus,

they are still a bit rough and I think I'm going to hog them out a bit more, but that's the idea. They are right around a 1/4oz right now and I think I can shave another few grams off before gluing them in.