Birman

I'm ready to joing the wing panels on my Venture 60. The wings were built on a FLAT surface and I was extremely careful when I set the dihedral angle on the two root ribs with the dihedral gage. If I clamp the two root ribs together I get a perfect mate of the two panels with no gap. When I put the dihedral brace in, I get a big gap between the root ribs. When the wings were clamped together I held the dihedral brace up aganist the trailing edge and the angles of the wing and brace are off quite a bit.

Does anyone have a cure other than trying to figure out how to cut a new dihedral brace with an angle to match the wing?

Has anyone else run into this problem?

I welcome all comments.

Thanks,
Larry

surf

Birman, I have not built this particular plane but would ask if the instructions give a dihedral dimension at the wing tips (?). This will tell you which is correct; the root ribs angle or the dihedral brace. I would suspect the root ribs are off just because you have to glue them at the correct angle (which I have goofed up before) and I would guess the manufacture cut the dihedral brace correctly.

If there a two dihedral braces that gule flat against the spars one on each side (fore and aft), I would make pieces of balsa that will set the wing tips at the right hieght (dihedral) and glue the wings together even if there is a slight gap at the top of the mating wing root ribs.

It's best to have the correct dihedral and I have never seen a wing separate at the root. You can always wrap some glass around the two joined wings.

Birman

surf, the wings are not blocked up to set the dihedral. There is no dimension given, only the angle. The dihedral brace (one only) goes between the upper and lower hard wood spars.

RhyanO

Hey Birman,

I also am building the wing of my Venture 60. I just have the left wing built right now, so you are a bit ahead of me on the build.
I would advise you to call Bruce (manufacturer of your kit) and ask him about what to do.
Since he designed the plane he has an intimate knowledge of its construction and will beable to advise you on what
the best solution is to your situation.

Best of luck,
Ryan

horace315

My Feedback: (15)

without the brace in do you get your clearances as per instructions at each wingtip? the dihedral brace can be sanded as long as you get your proper dihedral measurement at each wingtip. I have had the same problem with the braces and things off slightly off. instead of tearing the wings apart just adjust the dihedral brace to get the clearance you need and close the gap. those braces set the dihedral but don’t have to be an exact fit they add strength to the wing to help join it but it isn’t that critical as long as you get the proper dihedral as per instructions.

yel914

I had to make some minor adjustments to mine whle assembling but nothing too significant. How much of a gap are you talking about? I also made a change to the mounting of the dihedral brace and shear webs. I installed two shear webs per rib bay where the dihedral brace installs between the spars. The new shear webs are fore and aft of the dihedral brace, essentially creating a box for the dihedral brace. Worked great and I sleep better!

surf

Birman, I think RhyanO has a good suggestion. If not able to do that you could always use the 'angle' given in the instructions an cut some shims. The dihedral brace does add strength to the wing joining so I would want to ensure a shug fit regardless of what method you end up using. Dihedral doesn't have to be spot on for the plane to fly well, if fact I have built many witout dihedral to spice up the performance.

BruceTharpe

My Feedback: (1)

Larry, my opinion is basically the opposite of horace315. I put a higher priority on the strength provided by the dihedral brace and the fit of the wing center joint than the wingtip measurement. That's why a measurement isn't provided in the instructions.

The strength of the center wing joint mainly depends on the dihedral brace making firm contact with the top and bottom spars. If you sand the brace to make the joint come together properly, then you are sacrificing strength. However, a good center joint is important too. You want the ribs and sheeting to meet tightly. That in itself doesn't provide a lot of strength, but adding the fiberglass tape will tie the panels together and add strength.

At this point, I would recommend cutting a new dihedral brace to match whatever angle your wing panels dictate for a tight joint at the center. Let me know if you need some plywood, I'll send it right out.

Deadeye

If every kit maker supported like good ol Bruce, we would have a world full of happy RCers! Cheers to BTE!

Birman

Bruce, thank you for your input. I now feel comfortable making a new dihedral brace. I have the plywood on hand as well as a band saw and belt/disc sander. I will make the new brace the same height as the one you provided as it is a nice tight fit between the spars.

Larry

horace315

My Feedback: (15)

you don’t include dihedral measurements in your instructions? you are talking about assembling wood parts and sanding them. no kit I have ever built has came out exactly the way the instructions said without adjusting here and there. and the center joint on any kit/wing is very importiant,and a good tight glue joint is almost a must to have a strong wing. most dihedral braces I have put in you could move up down back forth about 1/4 of an inch. what you are saying is that lets say you put in the brace and it makes for a tight fit in both sections of the wing joint but something is off, brace root ribs ect,,after installing the wing on the fuse, you measure from wingtips to the flat surface it is sitting on, one side measures 3" and the other side measures 3 and 1/2 that is acceptable? adjust the brace to get everything even on both sides otherwise you are going to have trim problems. you use 30 minute epoxy and if the dihedral brace is a little loose it wont move an inch after cured. if the root ribs were installed properly like was said then you want as tight a fit between the two ribs as possible, if your wing/dihedral brace is off and you don’t measure the heights on your wingtips and I check each side before gluing you still will have a problem with one wing being higher than the other and that means shimming the wing saddle to make up the diference.plus most kits go off of the wing measurement to align the vertical and horzontal,stablizers.i know this is a bit long winded but maybe I missed something here or you meant the same things i have been building models for over 30 years and have ran into a lot of similar problems but always build them strong straight and true. I have never had a wing failure due to dihedral brace breaking or coming loose, or wing separating at the middle/brace.

Hobbsy

My Feedback: (102)

Horace, the only way what you're suggesting is possible is if you don't have the wing joint in the center of the fuse. No matter what you set the dihedral at, placing the joint in the center of the fuse will make the wing tips the same distance from the flat surface unless the fuse is crooked or uneven.

horace315

My Feedback: (15)

Hobbsy
you haven’t built many kits then, you assume that a kit is perfect and built that way.im sorry I beg to differ with you, I have had very few kits come with everything true and straight, and taking into account on the builder not taking anything from Birman a slight misalignment in the center amounts to a lot at the tip, and most aren’t noticeable at the root rib unless you take the measurments.you assume that the dihedral brace is perfect and the spars and everything else.

that’s not what happened here as stated.

Birman
If I clamp the two root ribs together I get a perfect mate of the two panels with no gap. When I put the dihedral brace in, I get a big gap between the root ribs.

so something is off?wing,dihedral brace?

piper28

FWIW, I found I had to sand the brace a little even to get it to fit between the spars. So while doing that, I was able to adjust the angle of the brace a little to make the wings match up together properly. But if the brace slides in properly without that sanding, I'd probably go with what Bruce says and cut a new one. Hard to argue with what the kit designer says .

Birman

Thanks everyone for all the input. I'm going with Bruce Tharpe's advice and making a new dihedral brace.

Birman

horace315

My Feedback: (15)

I am sorry to anyone on this post if I came across as condemning anyone’s building abilities or openions,that isn’t what I was trying to do. and to Hobbsy,i have built hundreds of models over the years and have came across some pretty strange things and problems some on my part of making mistakes in building and a lot of material problems that I had to make corrections to, that is what I meant by saying you haven’t built many kits. that statement was not meant in any way as an insult.

Hobbsy

My Feedback: (102)

I still say that if both halves of the wing are the same length from the center the ends will be the same heighth above a flat surface if centered in the fuse regardless of the angle. Each wing half is one side of the angle whether 4 degrees or 45.