Rear Fuselage Skins Done

Time: 5.5hrs

A momentous day for the airplane. Today the rear fuselage got closed up. Before closing it up I doubled checked that all the holes that need to be dimpled for the parachute area where correct. The only way to really check is to place the cover one the parachute box hole and verify that any holes that are covered by the cover skin are dimpled. I missed two on the right front side so it was good I checked.

Lots of photos below

Here’s the left and right side, checked and ready to go for riveting. The two areas I had some fitment issues where the tail cone along rib 6 (I think) and up in front on the right side along the join to the bottom skin… maybe 10 rivets. Other then that everything lined up great.

All the dimpling finished and checked for the parachute area.

Com1 antenna mount in place. I’ll need to install a few rivnuts here later for mounting the antenna.

Top of fuselage along the join. I used an edge tool to put a bit of a bend on the edge so that it seals well. Seems like it will work well. Thanks Peter for sharing this on your build log.

This is the luggage door area. The spot where the open rivet holes are have a spacer behind them. The spacer fits between the inside of the skin and a channel piece, But I noticed that the spacer they give isn’t really thick enough so I’ll have to make a thicker one or add to the existing. I found this after I riveted it and saw that he skin was being pulled a bit so I drilled out the rivets. I’ll have to come back to this.

Here’s where the space goes. It’s a good size gap, probably 1/8″ or a little less.

Here’s the spacer only about a 1/16″

Almost done

A good shot of the holes that I sized up to 4mm. There are a few on rib 6 and the last 4 holes on the top join. The long line on the top to bottom skin join is because of a prior issue with the skin and the longeron holes not lining up.

Still need to do some work here.

And it’s done. It all came out pretty good. Not too many bumps or pulls in the skin.

The only area that may need some work is the top middle section right where the com1 antenna and parachute box area is. Even though I made a spacer along the rib for the antenna bracket there is bump in the skin. It’s not that big of a deal since the parachute cover will cover that area up, but it would be nice to get it looking better. I did notice that even on the factory built planes this area is bumpy so I don’t feel too bad.

So next is to finish up riveting the luggage area… floor, parachute box, etc. then I should be good to put the front fuselage side skins on.

 

Grommet Edging for Rear Fuselage Ribs

Time: 1.5 hrs

Things done today:

  • Drilled out a few rivers on the tail cone/rear fuselage skin area to 4mm
  • Installed edge grommet on ribs where wiring passes through

This was suggested by Jean. He said that sometimes even if the wiring is wire tied it will rub on the edges of the ribs. I went through and installed a small piece of edge grommet on all these areas… maybe 10 or so. I wish I would have thought of this before the bottom skins were on… boy what a pain to do this now.

Forever One

Time: 3.75hrs

Things done today:

  • Partially joined the rear and center fuselage sections together. The center fuselage side skins are still not riveted
  • Loosely ran the rudder cable through the center fuselage… Need to tighten bolts on the sheathing part.
  • Installed the long elevator control rod in rear fuselage

Today was a milestone in the build. I was able to join the rear and center fuselage sections together. Rivets were put in the bottom skins and lower longeron to rib joins. I haven’t riveted any part of the side fuselage skins yet, just in case I need to work on something in the center fuselage. I’m also thinking that I may need to take the whole assembly off the work benches and put it on the floor so it’s easier to work on it.

A row of 4mm rivets joint the bottom skin. The second row of 3.2mm don’t do anything, they just fill the holes in the skin.

Inside looks at the rear to center fuselage join. I needed up having to remove the luggage floor it was just too difficult to reach all the rivets with it installed. The rivets on the inner ribs (CF-RIB-006 L&R) were nearly impossible to install, especially the left side where the rear elevator control tube is installed. luckily the holes I drill yesterday lined up well so it wasn’t;t to difficult getting the rivets in their prospective holes.

It almost looks like an airplane. Here’s an outside look at the joined sections. I need to remove the protective covering from the rivet areas on the center fuselage side skin… will have to add that to the task list.

Should Have Been a Surgeon

Time: 4.25 hrs

Things done today:

  • Checked the fit of the rear to center fuselage joining
  • Drilled missing holes in center fuselage ribs (CF-RIB-006 L&R) for longereons (RF-LGN-701 L&R)
  • Reamed holes in bottom skins of the rear and center fuselage to 4mm

Of all the holes to be missing it had to be the ones on CF-RIB-006 L&R, the ribs closest to the center of the fuselage. Also having installed the soundproofing didn’t help either since the holes were so close to the bottom skin. Some how though I managed to drill them out to match the hole sin the longerons (RF-LGN-701 L&R). Thank God for the lightning holes in the ribs and the flexible extension I bought for the drill. After drilling out these near impossible holes I thought… You know I should have taken the advice of my 10th grade Biology teacher who told me I should be a surgeon after having removed the fetal pig’s brain in one piece with only a scalpel. Well if I did I probably would have had enough money to buy a brand new Cirrus SR22 and not need to build my own plane, but then again where’s the challenge in just buying something.

OK so lets start with how I managed to maneuver the rear fuselage into place. Fortunately the rear fuselage is very light, but it requires a bit of an angle to get it into place. I used a large piece of PVC tubing so I could roll the piece around while I ran from side to side to see how things were lining up. This worked out great since it added a bit of an angle to the rear fuselage and it made it very easy to push and pull slightly to get things to line up. Once I got the bottom part to line up with in the center fuselage I clecoed the bottom skins together… see next photo

The rear and center fuselage skins clecoed so they don’t move. Note the second row of holes is because I have the updated rear skin, but and older center skin. The second row of holes will be filled with 3.2mm rivets just to fill in the holes. With that done I just used a box of printer paper under the rear fuselage and pushed in forward until the holes in the side skins lined up with the center fuselage.

Side skins line up well so those were checked as well. I found that it was easiest to leave the center fuselage skins free to move a bit so that lining things up was easier. I would definitely not follow the manual which says that by this point the skins should have been riveted to the center fuselage… I think that would have made things a lot more difficult.

Here’s the join of the center and rear fuselage (right side) where the center fuselage side channels (CF-CHL-032) join with the longerons from the rear fuselage. Everything lines up great.

And here’s the highlight of the day. I managed to drill these three holes out as well as three on the right side using the flexible drill extension through the lightning holes on the other ribs. In fact I was so proud of myself that I had done this I walked right into the garage door that I had put down about half way to keep the wind out of the garage. If I only had a video of that 🙂

Here’s the tool that saved the day… $10 from Home Depot.

Once the impossible holes had been drilled in the ribs I went on to reaming out the joining holes in the bottom skins to 4mm as directed by the factory. Here they are all reamed out. The last thing to do was to pull the section apart and debur everything. Now I’m getting very close to permanently joining the two sections together. I’m thinking I should be able to do it tomorrow. I just want to make sure it OK to do so I’ll look over my Task List and make sure I’m good to go.

Magnetometer and Luggage Floor

Time: 1.5 hrs

Things done today:

  • Installed the bracket for the magnetometer
  • Riveted rear bulkhead
  • Test fit the luggage floor and drilled out a few missing holes in rib 3
  • Riveted the rudder cable guides

Garmin magnetometer bracket mounted. I forgot to take the photo before I put in the luggage floor so the photo isn’t all that great.

The luggage floor fits well. It was a bit of a challenge getting it in though so I’ll try to leave it in here and just not rivet it yet. Besides having to run some cable I think it won’t get in the way too much.

Rudder cable riveted in place via the four plastic guides. Note that the cables cross in the lower left side of the photo.

More Rear Fuselage Work

Time: 4.5hrs

Finished up riveting the rear fuselage skins. I still need to mount the magnetometer bracket and then I can look at joining the center and rear fuselage sections. Also I need to see if I can get a new longeron RF-LGN-302 since the holes in mine don’t line up with the holes in the skins. 

Left side all done. 

Some photos trying to show the location of where the steps go. The top row has 4 rivets and the bottom has 5. So no rivets in these holes yet. I think I got it right… there’s no mention of the steps in the Sling4 manual so I had to look at the Sling2 manual to see where they go. 


And right side is done too. 

Rear fuselage skins

Time: 4.5hrs

Things done today:

  • Clecoed large skins for rear fuselage
  • Clecoed and riveted smaller skins for rear fuselage

Finally was able to start riveting the rear fuselage skins to the frame. Everything lined up very well. There were a few holes that needed to be reamed to get the rivet to go through. I left a lot of the protective coating on the aluminum. That’s why it looks a bit odd.