F-804H Sideplate Position?

[bmurrish]

This question is directed at Wicked Stick, but if anyone has -8 build experience please chime in. I will cross-post on the other site as well.

How can you tell the exact horizontal and verticle positioning of the F-804H Sideplates? My wing spar spacing is adjusted to exactly 1 7/16" according to plans. There is about a total of 3/16" F-804C flanges not covered by the F-804H sideplate. Is this correct or should both sides be flush? Also, how do you determine the verticle position? If you make the top of F-804H sideplate even with the bottom of the upper longeron (remembering it is upsidedown now) the three temporary tack holes line up right on flutes in the F-804C flanges. F-804H was fabricated according to plans and has been tripple checked. Lastly, what is a temporary tack rivet?

[Wicked Stick]

This question is directed at Wicked Stick, but if anyone has -8 build experience please chime in. I will cross-post on the other site as well.

How can you tell the exact horizontal and verticle positioning of the F-804H Sideplates? My wing spar spacing is adjusted to exactly 1 7/16" according to plans. There is about a total of 3/16" F-804C flanges not covered by the F-804H sideplate. Is this correct or should both sides be flush? Also, how do you determine the verticle position? If you make the top of F-804H sideplate even with the bottom of the upper longeron (remembering it is upsidedown now) the three temporary tack holes line up right on flutes in the F-804C flanges. F-804H was fabricated according to plans and has been tripple checked. Lastly, what is a temporary tack rivet?

Hi Bill,

I'll do my best to comment on this part of the slow build for you.
First I made sure my spar spacing was as exact as it could be by having my local machine shop mill up 4 aluminum stock bars that would simulate the exact thickness of the wing spars. (I mic'd the thickness of them before hand for the machine shop) (this was probably overkill, but figured it wouldn't hurt to be as precise as possible for it.) I also had them drill the holes (slight oversize) so I could bolt them to the spar just like the wing would be. Others have used a very hard wood instead, and others have used threaded rod with nuts to adjust the spars to the proper spacing.

My 804C bulkheads came pre-fluted from Van's... I almost wish they handn't cause some of the flutes were in the wrong position to match up with the 848 gussets, but that was a minor fix.

The 804H side plates don't have to be flush with the flanges of the 804C's, but you do want to make sure it's positioned so there equal edge distance when the drilling starts. I think I drew centerlines on every bulkhead and the 804H plate and drilled a couple of 1/16 pilot holes to check the hole edge distance before drilling to final size. USE THE PRE-PUNCHED SKINS F-820 & F-823 to align the 804H plate properly. Be sure the plate does not come in contact with the top 887 longeron (same goes for the 802D plate) and also make sure the 804H plate doesn't go below the spar or the bottom skins will hit them. I did have to massage the position of everything a little to get it close It never aligned perfectly all the way up and down, but it did manage to stay within a decent edge distance top to bottom along the rivet lines.

The tack holes are not suppose to be in the area where the final rivets will go, so I guess that's why Van's chose to place those holes on the flute areas. The tack or "temporary rivets" are there only to hold the plate to the spar bulkheads 804C's so you can position and drill the skins without the 804H slipping or moving during the process.

USE THE PRE-PUNCHED SKINS to LINE it all up. Check all the measurments and edge distances. Refer to DWG 20 for the height of the bottoms of each station bulkhead from the reference plane of the jig. Pilot drill a couple of 1/16 holes to check everything if your unsure, and if you are satisfied with it, then drill to final sizes. I had a couple of areas on one side (left) that I didn't like the postion after drilling a few holes. So I moved it a bit to get more even spacing and ended up drilling a couple of the holes to a -4 rivet size instead of having an oval -3 hole.

Also, when it comes time to rivet these side skins on.. Use a trick I stole from Jim Daniels site.. and pre-rivet the 820 and 823 skins to that 804H plate around the spar area where there's no 804C bulkheads. You can easily squeeze them on the bench cause there's no way you can buck or squeeze those last couple on the bottom.

Send me your phone number in an e-mail if you have further questions, and a good time to give ya a call. I can also e-mail you directly some pictures of the areas your wanting to look at.

davidrgr@comcast.net

[bmurrish]

Thanks Dave, I sent you an email with my number.