Not much to add to last weeks post to be honest. This week started out by riveting more of the baggage area…
And in between riveting the fuselage I started riveting the flap together.
It’s funny how quickly it all comes back when you work on something from way back in the project.
But eventually, all the flap riveting was finished and it is ready to be mounted back on the wing.
So, back to the fuselage the firewall sealant had arrived which meant that I could finally close up the front of the fuselage. I pealed back the side skins and applied the sealant.
I applied sealant to the bottom of the firewall (top in this picture) and then riveted every rivet I could reach in the forward side skins. Lastly, I fitted the floor skin and cleco clamped every hole.
That’s it for this week. I know it doesn’t seem like much but given the circumstances I think it’s making great progress.
Well, here we are still in the middle of the Coronavirus lockdown with the fuselage ready to be riveted. Following my last blog, it was lovely to have offers of help from people, but it’s really difficult to wait until after lockdown and it wouldn’t be right to ask the usual suspects to come over now so I resorted to relentlessly nagging the family!
It worked! My wife, Karma and son, Jake both relented and helped me get some riveting done this week. First Karma helped me rivet the F-704 bulkhead and the armrests in the seat skins for a couple of sessions.
Then Jake helped with F-705 bulkhead, baggage supports and the F-706 bulkhead in the baggage area.
Overall good progress this week considering.
Riveting is tiring work so, not to put the volunteers off riveting for life, we kept the riveting sessions short.
While they recovered I looked for anything I could find that could be riveted solo, like the aft rivets.
And the bulkhead to longeron bottom rivet.
And the forward floor stiffeners to brackets.
And the rear floor stiffener to bracket rivets.
To make the best use of the rest of the build time I decided to build a replacement left flap that had been on my to-do list for a long time.
When I finished the original left flap the blind rivet didn’t set properly. After drilling it out the hole enlarged. So I used a larger -5 rivet but that meant that I didn’t have the right edge distance. Also on close inspection the flange of the rib inside the flap didn’t sit flush so a lot of the rivet is between the flange and spar.
While it was probably no problem at all, I didn’t like having such a problem with my pride and joy. So, for all those reasons about 18 months ago I ordered a replacement left flap to be built when convenient.
Well, now is convenient. So I got the box of bits out of storage and started clecoing parts together.
It felt weird – but fun – going back in time building something i’d put behind me some time ago.
Before long the flap parts were all prepped and ready to disassemble for scuff, debur, dimpling and priming.
That’s enough for this week. There’s just the main flap spar, bottom skin and top skin left to prep – next week. Oh, and more fuselage riveting when I can convince the crew!
So the paint was dry (enough) and I could start reassembling the fuselage for the last time.
It’s been a long time since I last riveted anything so I started with something easy, the bracket for the autopilot servo.
Then the stiffener for the aft F-706 bulkhead.
Once that was done I put jointing compound on and cleco’d the F-706 bulkhead into the aft fuselage.
Next I riveted the gussets onto the firewall as per the instructions.
And riveted on the angle brackets to the forward longerons. I won’t rivet these onto the firewall until the fuselage is together.
I then pre-riveted on the Gear Attach webs to the F-902 bulkheads. Doing it now is much easier than when everything is back together.
Next I riveted on the nutplates to various bulkheads.
Then the F-704 doubler plates.
Next I fitted and torqued nuts and bolts to the F-704 bulkheads as per the plans. Again much easier to do now than when it’s all together.
Then I fitted and riveted the outer seat ribs.
and torqued the bolts. (If you’r building don’t do this now, it interferes with 2 rivets you need to set).
As I’m building a tailwheel I filled the unused holes for the main wheels with AN4 bolts as per drawings.
Then I got stumped.
The plans have you run the wiring down the centre channel all the way up to the F-706 bulkhead. There are holes for the wiring in everything except the F-706. I can’t see how or where to drill 2 wiring holes without weakening the structure or interfering with the elevator push rod.
So I called Richard for a quick brain storm. In the end we agreed the best way was for the wiring to transition from the centre of the aircraft to the next ribs under the baggage floor. But, the baggage floors are supposed to be riveted into place permanently.
As there were nuts and, now, wiring in that bay, I didn’t like riveting up the floor permanently. So I called Nigel (my inspector) and asked permission to make the baggage floors removable.
He said that was find so the next job was to fit nutplates to all the rivet holes.
That took about 4 hours to do everything and in some places it needed the one legged nutplates.
Eventually they were all done and I was pretty happy with the results. Only time will tell if anything else interferes with any other parts.
Once I was happy with the centre section and there was nothing more I could possibly think of doing it was time to flip it and attach it to the aft fuselage again. Thanks Jake for your help.
I then started locating all the parts and reattaching them.
While on a tea break I spotted that I’d missed priming an overlapping part of the structure. Doh! So I quickly knocked up both primers and got it done.
Next I started riveting any hard to reach rivets that could be done now such as the three aft arm rest rivets.
Next I riveted the aft support rib as far forward as I could – some overlap with the side skin so I left those.
Finally, it was time to fit the main side skins. But first every contact surface needed JC-5a jointing compound.
Then on went the skins.
Once the skins were on I started fitting all the parts to the forward fuselage.
I peeled back the front of the skins just enough so I could rivet the angle bracket to the fuselage.
Then I looked for any more rivets I could do alone such as the ones around F-704 wing slot.
Finally, I fitted and torqued the 4 bolts that attach the firewall to lower longerons.
That’s it, everything I can do solo is now done. What’s needed next is a riveting buddy. Any offers?!
After quickly finishing the last little bit of work on the armrest reinforcements it was time to wash and degrease the last of the parts. Some of these parts were so big they had to go outside to be degreased.
As before, I knew when the parts were grease free when the water sheet off the parts. The dog thought it was party time.
Eventually all the parts were washed and degreased and it was time to spray it all with etch (wash) primer.
Once the etch had dried I then sprayed the cabin parts with acrylic 2k paint in my chosen colour – RAL7001.
Anything that was not going to be visible in the cabin I sprayed with PR143 primer.
I also primed any parts of the outer fuselage that overlapped other parts.
I did the same on the massive longerons. The aft section was primed with PR143 and the forward part was painted with RAL7001.
I also realised that there were a bunch of parts I had primed previously – like the firewall and F-706 bulkhead that needed to be painted so I gave those a shot of RAL7001.
and the uprights for the mid section.
Finally I took the big F-770 skins outside and sprayed them with RAL7001 too. The first one sat there and dried within an hour or so. I swapped it out with the second one and gave that a coat of grey.
As soon as I’d finished spraying the second skin I was done painting. Yay! So I started tidying up the workshop.
After about 10 minutes into the tidy up I heard an almighty clang coming from what I thought was a neighbours house. Until it dawned on me…
NO it can’t be!!!! Please no!…
Yes, it was my skin! A gust of wind had caught it and slammed it to the ground!
After a moment of staring in disbelief, I grabbed the skin as carefully as I could and put it back on the table. While I waited for a break in the breeze so I could safely run into the workshop and grab a piece of wire to tie the skin to the table to stop it happening again I examined the damage.
There was nothing I can do while it was wet so I left it to dry.
After about 4 hours I came back to the skin and decided to sand off the affected areas. The paint was only 4 hours old so it should come off pretty easily.
I started with some maroon scotchbrite pads. Useless! Didn’t even mark the paint.
So I used some 400 grit emery paper. A very light mark but it wasn’t making any headway!
So the good news is this paint is tough! Perfect for high wear area like the cockpit.
In the end I used 200 grit sandpaper and smoothed as much of the damage as possible and worked back to the emery and then the scotchbrite.
I then took the skin outside, set it up on the table (tied of course) and then sprayed over the sanded areas.
What a week but I’m glad the painting is all done!
Well here we are in the middle of COVID-19 lock down. Work had been really busy for us helping everyone get set up working from home but this week things have started to calm down a bit.
So, what do I do with this spare time? Build on!
I spent a whopping 21 hours this week preparing all these parts for painting. Starting with the big side skins.
Every single hole gets deburred…
All the pen marks and printed marks need to be removed with solvent…
Then the entire thing gets scuffed so the primer can stick better…
Next I cover all the holes that should NOT be dimpled! This involved a lot of checking the plans and others builder logs.
Finally I dimpled all the open holes.
Next I detached the centre section from the aft fuselage…
And removed the bulhead for deburring…
Next I removed the massive longerons…
Countersunk and prepped them…
With a little help from Karma I got the centre section onto the bench and deburred as much as possible.
As well as the main bulkhead…
I scuffed parts of the aft fuselage where it would be overlapped by the centre section.
Once all the deburring and prep was finished I then finished the week by washing & degreasing as many parts as I could get done.
Parts that were washed were hung up to dry.
Once the parts had dried I put them in a storage container (lined with new packing paper to keep the parts clean).
Finally, after much thought and consultation with the RV Squadron forum, I decided to make reinforcements for the armrests. I’ve seen more than enough damaged armrests to convince me this was a good idea.
So, what a week! After spending so much time on this it’s weird that it feels like I haven’t made a dent! Hopefully next week will seem more productive.
As I’ve been disassembling I’ve had this nagging voice in my head telling me I’d missed something. Sure enough I had missed a couple of 1/8″ holes that connect the F-902 bulkhead to the longeron. Not a massive problem and easily done after the fuselage is rebuilt but luckily I was able to do this now while those parts were still together.
Once that was drilled I then went on to dismantle and prep the F-604 bulkhead.