Tip Up Questions

[Tbone]

Just a few...I promise. After fitting the Canopy frame (WD-716) to the fuse and all the skins to it, along with the canopy stiffeners, with clecoes, I "think" I am ready to start fitting the canopy. The only thing that I haven't finalized is the rear canopy "bows" to the WD 725's. I have adjusted to the required degree bend and fluted to make somewhat flat. I have riveted the canopy frame to the 725's and have a good fit in the C702 (FWD SKIN) to the F771 (Forward top skin). My questions are should I rivet the C702 to the canopy frame at this point? The clecoes would be in the way. ( I haven't fit the struts yet or their brackets to it) and does the Aft top skin ( F744 ) need to be removed for trim work on the plexi? Also would there be a problem not yet fitting the rear canopy bows to the WD-725's yet? Seems that I read that the area could be tricky in a tight fit to the canopy. What would be the correct or "allowable" procedure? Any areas or "gotcha's" to look out for?
Any web sites that show a detailed procedure? Thanks!

 

[dhall_polo]

should I rivet the C702 to the canopy frame at this point?

I don't think there's hard and fast rules here on order, but I think it is best to have the frame fully assembled and installed, minus the bows and latch fingers, prior to canopy trimming.

( I haven't fit the struts yet or their brackets to it)

I would recommend fitting them.

does the Aft top skin ( F744 ) need to be removed for trim work on the plexi?

You don't need the aft skin installed for trimming, but you *could* have it installed.

Also would there be a problem not yet fitting the rear canopy bows to the WD-725's yet?

You don't want the bows installed until the canopy is trimmed, because after the canopy is split and trimmed, you will adjust the bows so that they are pressed against the canopy. (with shims for sikaflex).

Any web sites that show a detailed procedure? Thanks!

I'm sure there are plenty. I have a few pics at http://donka.net/gallery/rv7canopy

 

[Tbone]

It shows on your site that your tip up frame did not have the skin riveted on. Did it remain so during the canopy trimming? Also any advice on how pertinent is the fore/aft centerline to be on centerline to canopy and how is the best way to measure and if a variance is acceptable?

 

[Rupester]

Tip-up order of assembly

LIke a couple of friends who are doing tip-ups, I did all the prelim canopy trimming with the 702 skin clecoed on the frame. I will not do final trims until the frame and 702 skin are riveted and the underside reinforcements are done, however.

 

[#N72CR]

Here is a link to my pictures. I would have tip-up frame complete (riveted), before cutting the canopy.
I probably made 30 cuts, before it was all done. I started with about 3/4 inch off the front. then cut another 3/4 inch. then smaller cuts. Be sure to sand the edges with a coarse sanding block after each cut.

 

[Tbone]

Thanks for the help. Another question... I have done the prelim cuts on the front, sides, and rear of the canopy. I have yet to finalize anything. The manual states that the upper part of the canopy won't touch the roll bar until it is split from the rear. I have about 1 inch clearance. When I mark the split line and cut it it seem that when the forward and rear parts of the canopy will naturally fit better but the split line will have a larger gap at the lower edges. Is this normal and if so what is the remedy to align without affecting the front and rear lines of the canopy? Also I have done the S/B on the reinforcement (634A?) and don't think I will have the necessary edge distance of 1.25. Do I notch this out of gradually blend back to the required distance?

 

[D-Dubya]

Split Line

You are correct in reasoning that the gap will open up at the lower edges after the Big Cut is done. It's no big deal...mark the cut to center it on the roll bar (or whatever Van's calls it), and just make it as straight as you can. You can sand it after it's been cut in two to make it fit to the exact centerline. There should be enough meat left in the back half of the Plexi to make up for the 1/16" or so material that you sand away.

If you are really worried about it, you can "cheat" the bottom of the cut line aft at the sides if you want, but don't get too carried away. It doesn't move much when the canopy closes the remaining inch. Doing that will have the forward half very close to lining up with your marked roll bar centerline, and you can start fresh on the rear half to make it match up to it.

Regarding the second half of your question, I'm not sure what an S/B is.

 

[Tbone]

Thanks for the help Dave. The S/B 05-1-1 is the service bulletin on the reinforcement of the F732A at the rear. Extra parts and such. I believe that you can find more info @ vans.

 

[dhall_polo]

s/b 5-1-1

Many/most of those older S/B's are already merged into the kits as standard construction. My kit already covered this in the directions (slow build). Was this not baked into your kit?

more canopy talk:

I actually had the wonderful opportunity to do two canopies. (ouch, crack) On the first one, I did not have the tip-up structure fully riveted or constructed. On the second, it was all done. Either way works fine. But it does make much more sense to have the structure riveted. The thing is a wobbly piece of junk until it's all constructed, so it's better to have as much done as possible.

As to your gap questions... Once you split the canopy, you will have an opportunity to really refine the fit of the two halves of the canopy. The big split cut is not your final iteration, it is only the first step. The first thing to do would be to make sure the edge on the front half of the canopy is trimmed and polished up to your centerline on the roll bar. Then you trim the rear canopy edge until it fits nicely to the forward half.

I bet I took the rear canopy on/off the frame 30 times, each time making fine adjustments. I even had to make a few more adjustments after final assembly in advance of inspection.

Don

 

[Bavafa]

Make sure the forward skin is in place

I agree with the way Don recommends it. The only thing I would add is that to make sure the forward skin (I think it is F-7106) is at least clekoed or temporarily riveted in place and the struts are installed. Both will affect the position of the canopy. Without these you might find out that you have shaved too much between the two halves.

Mehrdad
RV7A - flying

 

[Rupester]

What Mehrdad said. Clecoing on the front fuse skin is necessary to "rigidify" the whole subpanel and fwd fuse structure. W/o that the hinge blocks can move around, as then will the canopy frame. You'll also see that the canopy frame reinforcements have a similar effect on the frame itself. You 'll want that all solid and stable before you make final cuts on the Plexi.

 

[Tbone]

All great advice. I will re-cleco the forward skin on. Last night I started the lift strut install. I do have the tip up panel (F702?) finished all but riveting to the substructure. I don't believe that I will do that until I finalize the plexi cuts. I may have to shim the forward edge and such. The reinforcements are ready. Correct or any additional knowledge?