Fauvel AV48

Anything to do with gliders & gliding.
Sean Fitzgibbon
Posts: 57
Joined: 11 Oct 2017, 18:53
Location: Mitcheldean

Re: Fauvel AV48

Post by Sean Fitzgibbon » 05 Apr 2019, 14:07

Hi Doug, just wondering how your '48 is coming along and to ask a question.
I've fabricated the wing spars and I'm looking at starting the wing assembly. I began with the port outer panel and marked the rib positions on the rear of the spar then laid it flat on the board and attached the ribs vertically.
Problem I have is that the trailing edges of the ribs don't align properly, so my question is, did you build the wings over the plan in the normal fashion?
Cheers,
Sean.
Attachments
IMG_20190401_195501768.jpg
IMG_20190401_205359763.jpg

Doug Diener
Posts: 10
Joined: 25 Aug 2017, 00:44
Location: Seal Beach CA

Re: Fauvel AV48

Post by Doug Diener » 23 Apr 2019, 05:00

I just saw your post about the wings. I've been spending a fair amount time building and completing the wings. I found the wings to present several challenges including the joining of the wing sections, attachment to the fuselage, and getting the ribs properly elevated. As usual after completing one wing inner and outer panel the second set was much easier, faster, lighter and better built. To answer your question I built the aft part of the wing on the plans. Yes, there is problem with the TE needing to be packed up. The main spar was placed on the plan but packed up by a strip of 1/16 balsa for later shaping over the wing main spar when sanding to final shape. I saw this somewhere on the plans on in the build article. I then placed the ribs square to the spare and noted all the mis-alignments and scratched my head and said a few bad words as the alignments were not good. I did some guesstimation and created a tapered balsa spar/strip about 5/16 high at the root end down to about 1/16 at the outer end. This was pinned to the plan just ahead of the bottom 1/4 hardwood subspars for the inner area and just in from of the balsa TE along the aileron area. I also pinned a 1/16 balsa strip just behind the main spar to lift the ribs even with the bottom edge of the main spar. This leaves a 1/16 gap at the bottom of the ribs for cap strips added later. I then glued a few ribs to the main spar being supported on the tapered spar I made. Before attaching most of the ribs I clamped the lower portion of the TE to the ribs. I made my TE from 1/16 plywood beveled about 60% of the width of the TE to a sharp edge using my dremel tool with a 60 grit sanding disc. This TE was then clamped to the few ribs to check for alignment, the TE was supported by a straight hardwood spar to keep TE straight. I had to adjust things a little and then the rest of the ribs were attached. The top part of the TE is another strip of 1/16 plywood not beveled, that completes the TE, producing a tough TE 1/16 inch thick, again using clamps and extra wood spars (top and bottom) to keep the TE perfectly straight when gluing everything together. For the front part of the wing ribs I supported the wing vertically (hanging down)from my work bench by screwing some short horizontal wood blocks to my workbench and clamping the main spar to these blocks (the front of the main spar is facing up), after marking rib locations on the front of the main spar. I marked the midpoint of each rib front and used this to align the ribs as I glued them to the main spar. I use a adjustable protractor and a little balsa jig to align the ribs. Some of the ribs needed a touch of sanding to fit flush against the main spar and to stay in alignment. I hope this verbiage is helpful. I may have some pictures and I will check later
I also found that the ailerons were much to flimsy when built as shown on the plans, so I added cap strips and diagonal reinforcements and this stiffened them up. I used the same procedure for the aileron TE and they turned out straight and should be hanger rash tough.
Keep up the build as today I joined all the wing sections together and attached them to the fuselage, WOW what a beast, can't wait to get all the sanding finished and escape from the piles of balsa dust. doug

Doug Diener
Posts: 10
Joined: 25 Aug 2017, 00:44
Location: Seal Beach CA

Re: Fauvel AV48

Post by Doug Diener » 30 Apr 2019, 00:15

Here are some photos of my build
Attachments
IMG_0537.jpg
outer wing panel, note the two recesses on either side of the incidence rod hole these are four the bolt heads used to attach the vert stab to the inner wing panel.
IMG_0535.jpg
the inner and outer wing panels joined together, the gap is where the vert stab fits between the inner and outer wing panels. The inner wing panel has been sheeted but the outer wing panel not finished yet
IMG_0533.jpg
the shows the outer wing panel (unfinished) being sled onto the inner wing panel, note the aft portion that will fit against vert stab, see next photo
IMG_0550.jpg
showing the completed union of the outer and inner panel with the vert stab and rudder installed, still have to sheet the LE of outer panel and addition of hardwood LE
IMG_0549.jpg
same as above
IMG_0539.jpg
The outside face of the inner wing panel, shows the attachment screw holes for attaching the vert stab on either side of the incidence hole
IMG_0542.jpg
showing the building of the wing adding the front rib parts by placing the wing vertical by clamping to temporary wood blocks screwed to the work bench
IMG_0543.jpg
as above
IMG_0545.jpg
similar procedure used to build the ailerons by building the ailerons onto the wing

Sean Fitzgibbon
Posts: 57
Joined: 11 Oct 2017, 18:53
Location: Mitcheldean

Re: Fauvel AV48

Post by Sean Fitzgibbon » 30 Apr 2019, 20:49

Hi Doug,
thanks for taking the time to reply and post your photos, you have made great progress!!
I think we have encountered exactly the same issues, which is reassuring, in a weird sort of way. I had come to the same conclusion about aligning the ribs, we had several discussions in the clubroom about how best to proceed and I think I will carry on in this fashion.
I can't help but think that cutting the ribs complete from the rear of the main spar to the trailing edge and perhaps incorporating jigging tabs, would have been a better method, but we are where we are now.
I'll check back in with you as I progress, as long as my sanity holds out!

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