RV-7/7a Plan Gottcha's

[wirejock]

Originally Posted by BillL

These bushings in the stick are problematic. The tube welded to the stick gets distorted slightly, then the tube is DRILLED, and it is typically no longer round. I have two sticks to prove it. You would do well first to ream the tube for the bushing, then measure both. It will likely be loose, but with a little extra length before installation, it will crush slightly and expand to help fill the gap. More than .001 clearance and the stick will be loose.

I have many more details and a long tale to go with them. Let us know more specifics of your problem.

My original stick was loose, in the tale, a new stick was purchased, still loose, and I made a custom bushing to fit. Fits nicely now, no slop.

Thanks. Mine are the opposite. I had to drive them out the first time.
They say grind to a slip fit but as you say, the holes really need to be dressed before removing material from the bushing. I believe the pilot side is just a tiny bit out of round but the reamer goes through just fine. I'm going to examine more carefully tomorrow before touching the bushing.
The other one, copilot, is slick with just a little polishing of the tube with 400 and 600.
Thanks

[sahrens]

Originally Posted by gasman

this faring will never need to be removed..... just rivet it on.

The fuselage plans have you rivet those locations. Later when you get the finishing kit you find out something else. Screw the fairings on or rivet them on does not change the need to know about those locations.

[BillL]

Originally Posted by wirejock

Thanks. Mine are the opposite. I had to drive them out the first time.
They say grind to a slip fit but as you say, the holes really need to be dressed before removing material from the bushing. I believe the pilot side is just a tiny bit out of round but the reamer goes through just fine. I'm going to examine more carefully tomorrow before touching the bushing.
The other one, copilot, is slick with just a little polishing of the tube with 400 and 600.
Thanks

Good Luck, you know that the 1/2" on each end really does the work, and if the bore, or bushing, is not straight it will bind. Check each end by inserting the bush just 1/2". If that helps, then you can chuck the bush in a drill and make it an hourglass shape with a few thousands off the center and help. Since the proper reamer goes through, I wonder about the straightness and concentricity of the bush.

Just a thought.

[wirejock]

This is a tricky spot. I found a few great tips using the search function. Credit goes to these two links.
http://www.vansairforce.com/communit...ghlight=F-605C
http://www.vansairforce.com/communit...ghlight=F-605C

Here's how I did it. YMMV
Cut F705B to length. Measure F-605C. On mine the bends were perfect. The bends determine where everything lines up. From the first outboard bend, measure 2" outboard and make a line. The next bend should land 3-3/4" from the end line. The inboard end of the bar should be 12-1/2" from the end line. Yours may be different. Mark a line at 6-1/2" from the outboard end line. That's where the taper begins toward the inboard hole. Make another mark 12-1/2" from the outboard end line. On mine it was exactly at the end of the inboard end of the bar. Measure 1/4" from the inboard end line and make a mark exact center of the bar. Center punch and drill a pilot hole. Enlarge to #31. This will be the alignment hole.
Draw a center line the length of both of the F605C bars and the F705B bar.
Locate the exact center of F705B and make a mark, center punch, pilot hole then finish #31 hole. Cleko F705B to the F705A bulkhead and clamp the ends making sure the alignment line is centered in all the holes. Match drill the holes leaving the bolt holes. I use a bushing with #41 hole to drill the bolt holes then enlarge to #13.
Now cleko F605C in place using the hole in the inboard end, square the ends of F-605C and F705B then clamp the ends with a shim. Match drill F605C through F705A. Go back through and ream all holes to the final dimensions.
Fabricate the F705H spacers just a bit longer than 1-1/2" and draw the center line. Insert it into place, mark where the hole will actually be located. Remove, center punch, drill #41. Clamp the two F705H spacers together and match drill then enlarge up to #12 reamer. Disassemble.
Mark F705C for the relief taper and cut away the extra making sure the edge distances are followed. Cleko parts back together.
Relieve the edge of F705H to fit.
Finally, cleko it all back together. On mine I had to cut about 3/32" off the inboard ends of F605C to match the F705B bar. Some have to cut both ends. YMMV.
I'm not saying this is the right way, but it worked out well.

[Warbo]

I've only just started building and still on the first plans page. I got to the step which says draw rivet lines on the HS-00001 as per the drawing shown below.
http://
When you look at the part it's clear that the 3/16" and 1/4" dimensions can't be correct. I rang Van's and they confirmed it. The dimensions are actually 3/8" and 1/2". So it turns out the problem is that the plans I'm working from had a number of errors including the wrong rivet callouts and a few of these drawings managed to get out to new builders. Lucky me was one of them.

This is the drawing (DWG3 R3) with the errors.
http://

And this is the drawing (DWG R4) that corrects everything.
http://

If you happen to be using DWG3 R3, there is an updated and corrected DWG R4 available from Van's.

[wirejock]

Ian
I recently disassembled and reassembled my HS. My fault performing the service bulletin. In the process, I found all sorts of errors on the instructions and changed the order of some instructions. You may want to check out the Empennage section of my blog. The rebuild is towards the bottom of the Empennage page. Thanks for posted the plans change.

[Warbo]

Thanks Larry. I've had a look at your blog - great stuff. The pictures of the finished items make so much of the plans confusion disappear. By the way, is it normal to spend more time staring at the plans than actually doing the building?

[wirejock]

Originally Posted by Warbo

Thanks Larry. I've had a look at your blog - great stuff. The pictures of the finished items make so much of the plans confusion disappear. By the way, is it normal to spend more time staring at the plans than actually doing the building?

Boy if I had a penny for every minute staring at plans!
I'm glad it helped.
It gets really bad when you start the fuse. The manual gets pretty brief.
Add all that time spent looking for parts too.
I've got a pretty good tracking spreadsheet with a full inventory. If not for the location column, I would never find stuff.

[DaleB]

Originally Posted by Warbo

By the way, is it normal to spend more time staring at the plans than actually doing the building?

Well, I have found that I have a choice. I can spend time staring at the plans instead of building, or I can spend time fixing stuff I got wrong because I didn't stare at the plans long enough.

[wirejock]

This one is a little gotcha but cost me a piece of angle.
The plan detail calls for the part to be cut 24-5/32. Cut it long. 24-5/16 is where mine ended up.
The reason is the hole where F-729C and F-729B are riveted together will end up far too close to the end of F-729B if cut to plan.
Start with a slightly long part. Drill the alignment hole in the aft end of F-729B. Cleko it in place and mark the part the longest you can safely fit against the forward flange of F-729A.
This will insure you have adequate hole edge distance when you match drill through F-729C.
Also, don't drill a hole in the top flange of the part. Allow the hole to fall where F-729C aligns.