Been trying to put the vstab skin on the ribs to cleco it in place. To me it seems like the radius of the bend in the skin is too tight. Can’t seem to get the holes to line up. I did radius the front of the ribs a bit. Is there a trick to getting it on or should I un-bend the leading edge a bit?
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Putting skin on ribs
- Thread starter BrianP
- Start date
You can bend the skin outwards a little to help open up the nose section. Taking care not to over bend it. I used ratchet straps to pull my skins on with stringers by the ribs and spars. You may have to add some backing near the trailing edges so you don't bend the skins when the strap pulls tight. You want to be ginger about pulling that all together so you don't pull the skeleton out of alignment. Some nose ribs may be massaged into place by taking out the bottom nose rib and pushing it with a stick of wood. Or if you need to push from the top, you can get a small length of steel rod and push through the tooling hole in the top VS rib.
Hey Brian,
Did you smooth over the nose rib as in the attached page from section 5? I would try to put the fwd most cleco in each rib on one side, then one cleco in each rib on the opposite side. Slowly work your way aft, back and forth. In your second picture you have a gap on the bottom. Take out all the clecos except the fwd most one, on each rib, and then transfer that gap to the other side. Slow and steady. Sometimes you have to push the rib fwd to get that first cleco in. I’ve also used a scratch owl to Gently persuade the rib hole into alignment with the skin hole. You may have to do that a little on each rib before you can get a cleco in.
As far as the dent goes, I use a teaspoon with tape on it and a little lubricant. Massage it back in. Get it close, painter will fix the rest.
Thanks
I did take some material off while radiusing the nose ribs but I’m guessing probably not enough. The rivet hole in the photo is a lot closer to the forward end of the rib than mine are.
I'm having a similar experience to this and see that others have it as well. Before I do the flute in the web, has anyone asked Van's about the strength of the rib with the flute in it? I understand that fluting the flange is okay because the load path travels through the web. However, with a flute in the web, there is now a location for the web to buckle since the entire web is no longer in compression without a bending moment.
Shouldn’t be any flutes in the web. The fluting is in the flange and is to reduce the distance between a set of holes in the flange. Fluting is also used for straightening ribs so they lay flat on your table. More info on this in section 5. Make sure the tabs and notches in the flange are smoothed over as in the picture above. I’ve even bent the edges of the tabs slightly to prevent any protruding of the skin, once riveted. Try with one hole clecoed on the top, then one on the bottom and work your way aft. I’ve also used a scratch awl tool to Very Carefully pull the rib forward into alignment. This works well if you can see about half the rib hole through the skin hole. Good luck
I had a similar experience with all the leading edges, control surfaces and wings.
As mentioned above, I finally was able to get the skins on the ribs by inserting clecos in the first hole of each rib on the top, then the first row on the bottom, and alternate back-n-forth, slowly moving to the aft.
I did get some... "imprinting" (I think it's called) of the ribs through the skin, even after following the section 5 rib faceting.
Below is a wing leading edge where I used a similar process.
Good luck.
As mentioned above, I finally was able to get the skins on the ribs by inserting clecos in the first hole of each rib on the top, then the first row on the bottom, and alternate back-n-forth, slowly moving to the aft.
I did get some... "imprinting" (I think it's called) of the ribs through the skin, even after following the section 5 rib faceting.
Below is a wing leading edge where I used a similar process.
Good luck.
Interesting thread. I'm building a -9A and note that on page 6-1 of the Manual (Horizontal Stab) there's a specific callout for fluting of the nose web to improve skin fit. "Cleco the HS-905 nose ribs into the HS-901 skin. The forward web of the inboard nose ribs must be fluted slightly to make the nose end slightly narrower. (Sec. 5N)". The OP @BrianP mentioned he's working on the Vertical Stab, and I don't see any reference to fluting in that section, but if I were facing the same difficulty with the skin I would have considered the same fluting of the web called for on the Horizontal Stab. Would that be an incorrect method?
