Firewall Sealed Off

Part of section 29 is to seal off the perimeter of the firewall to the surrounding skins to keep away any fumes or dangerous carbon monoxide from the cockpit. This is what I did today, reluctantly. Still working on getting over the flu and the associated coughing and congestion is annoying enough. Wearing a respirator and trying to get into confined spaces while wearing it and trying not to gunk-up the pretty paint job with firewall sealant didn't really sound appealing to me.
It wasn't appealing but I did it anyway to get it over with.
First I turned the fuselage on its side. thanks to the rollbar this is a one-man job still, despite the really heavy structure.


Then I masked all the areas around where the sealant was supposed to go.


Then I cleaned the application area with alcohol to ensure good contact of the sealant. By the way, I learned that the firewall sealant is much thicker than the Pro-Seal stuff used to fuel proof the tank (and which was used in other areas to seal off the firewall). So it requires much more force to push that stuff out of the cartridge which can get a bit tiring. Particularly as you have to finish off the cartridge in one run once you mixed the components. It's all or nothing.


I added some drop catching paper layers before knowing that the stuff is so think I wouldn't have to worry about it dropping.
It also dried very quickly and became to hard to nicely spread it out with a popsicle stick, so I will just get the look as it applied right out of the cartridge. Not exactly what I had hoped for.
I am now waiting for the stuff to fully dry and will then take the masking tape off. An attempt to do it right after the application showed that it comes off from the electric tape easily but then still sticks to the main string, so I decided to wait until it's cured before removing the rest of the tape.

Section 24 Completed

I am slowly getting over this flu and I was able to fool around yesterday for half an hour and today a little bit to complete section 24, the rollbar story.
Yesterday I just clecoed on the rollbar and its supporting structure to see if for one the rollbar would still slide over the bases and second to see if the overall fit was still satisfactory. Both questions were answered positively.


When priming the bases I remembered the inherent roughness of the green Cortec primer that I had used on the inside of the rollbar. So for the bases I didn't feel it was a good idea to use Cortec again as it might have made that sliding-over part very hard to accomplish. Instead I wanted a primer providing a slicker surface which the Napa 7220 stuff is definitely good for. That's why you might have noticed the bases in previous pictures to be grey in color after the priming.
I don't know if this was the reason why it all worked out well but I was definitely able to slide the rollbar over the bases without any help.

Then, today, I riveted all the parts together that were just clecoed yesterday. It wasn't much of a problem except for a lot of manual labor with the CQR (Close Quarter Riveter) as I refused to rivet the aft part of the brace to the aft bulkhead from the easy side. This would have been from the tailcone side which could have been done with the pneumatic riveter all along but then exposing the ugly warts of the shop head on the inside whre they'd been visible. Instead I riveted from the cabin side and that was a bit awkward to say the least.
Anyway, now that it's completed this will soon be forgotten. Enjoy the nice shots ...

Rollbar Painted - The Sequel

Despite me developing a full blow flu (in this temperature, go figure!) I was able to spray the other side of the rollbar and the reading light brace. The job turned out very nice again.


The scale has absolutely no meaning to this picture and shouldn't even be there. Please ignore it.

While I was feeling a bit better and waiting for the paint to cure I worked a little around the fuse, mixed some Pro-Seal and put the upper firewall onto the fuselage. I also match-drilled the little stub pieces of piano hinge and riveted them into place. I hope everyone at this step realizes that the upper screw hole for the nutplate that gets half riveted to the firewall and half to the side skin has to be dimpled for a #8 screw. If you riveted the stub hinges in place without doing this it's either drilling those rivets out again or dimpling the hard way by forcing the screw in. Not sure you like the looks of the later in such a prominent area.


The last thing I did before the flu took the best of me was to rivet the little diagonal stiffeners onto the side skin from the front inside area.


I took the photos tonight as I was just too exhausted this afternoon to do anything but lying down.

The next steps are messy and require firewall sealant to get spread around to seal off the cabin from possible fumes in front of the firewall. In my current condition I better hold off on that one until I feel better.
Maybe I can do some light riveting job with the rollbar while I'm forced to be at home...

Rollbar Painted Part 1

Early in the morning I prepared the parts for painting. The primer had dried nicely and the surfaces were quite smooth. To remove minor imperfections I sanded them with a maroon SB pad and then started the painting. Paint use anticipation was dead on and while the parts were curing I worked on section 29.
Most of the dimpling of that strip that goes on top of the FW I had done yesterday so now it was to rivet the nutplates and the strip in place. That went relatively easy although slow. A lot of care had to be taken to get those rivets in and the overlapping skins flat. Some of these needed the screw to go into the nutplate to hold everything down and in place.


Then the piano hinges for the cowl had to be match drilled. If you haven't cut them to length yet, make a note for 1201J, the longer one of the two hinges. The manual asks for it to be cut to 25.5" length. That is incorrect. It needs to be 26" long with the loop starting on the lower left side of the FW and that flat side in that little cutout area where the hinge pin ends will be stored.
How I know? Look at this:


I had to drill an extra holes to rivet down the end of the piano hinge and will have to fill the unused hole with a rivet.I believe the page where this incorrect length was mentioned had a revision number. Stuff like that just makes me angry. The drawing is incorrect either as it shows two loops on each end which is not would you need to do here to get the hinge over that hole.

After match-drilling and the deburring the holes had to get countersunk for AD3 rivets.


And then the hinges were riveted in.


And finally the rest of the vertically mounted nutplates were riveted in and the antenna platform was riveted on.


Then it was time to get the parts out of the paint booth and put them in the shop for the night.


They turned out nice, tomorrow the opposite side will get painted.

Lots of Invisible Things

That's what I did today. Despite a cold I developed just after the end of the work week yesterday, I spent a lot of hours in the shop today. You can hardly see what I did. Among the more visible things is the priming for the paint job coming up tomorrow morning. Then I screwed and torqued the rollbar bases back on and lacquer sealed them. I also prepared a lot of parts in the forward upper fuselage section 29, so I can work on that while waiting for the paint to cure tomorrow.
Dimpled the upper firewall and the little aluminum strip that will hold the cowl hinges, countersunk the nutplate attach holes, deburred everything and pulled additional parts that will need surface treatment and priming.
No photos, sorry. More tomorrow.

Rollbar Removed

I cleaned the fuselage from chips from yesterday, removed the brace to allow the rollbar to be removed, which I did as well and it went fairly easy. I am confident at this time that I'll get it back on without too much of a hassle.
I did some supplemental riveting for section 24. Riveted the nutplates in, added the rest of the LP3-3 rivets to complete connecting the angles, bulkheads and floors together.




I also removed the bases and marked them left and right by filing a mark into both of them indicating which side they have to go on. Deburred everything and stacked up the parts that need surface treatment and primer next.


Oh, and I also countersunk the last outside holes in the rollbar and the top attach holes in the rollbar brace that will have contact with the Lexan glass eventually.

Tomorrow, I try to do the surface prep in the morning and also prime a little later in the day, so I could paint on Sunday. Let's see how it plays out.

Rollbar Match-Drilled

Don from Texas had brought up a very good idea for the match-drilling of the rollbar. He suggested to hold off on that until the rest of the structure it connects to through the center rollbar brace has been put in place. That way you are sure that the alignment of the rollbar is correct. Apparently, a lot of builders found out later that the rollbar had to be pulled back a little to match the rest and that's a bit hard to do when you already riveted it to the bases at some defined angle.
I thought that was a great idea and so I did not start with drilling today but by putting the aft area of the fuselage into place. In order to do that I had to rip open the sealed off tailcone as two parts of the aft bulkhead were needed to match drill a little bracket tab in the front of the tailcone.


I was very pleased to find nothing in there that wasn't supposed to be in there. The seal had worked well it appears. Unfortunately, the 3M cream painter's tap eI had used when running out of blue tape had deteriorated tremendously over the time and did not want to come off clean. I had a very hard time even with MEK to remove the residues from the aluminum. Lesson learned, never use the creamy tape again. It's 3M but some nasty crap anyway.

After this cleaning session I fitted the bulkheads onto the fuselage. The little cutout for the longerons are very tight and I used a hand deburring tool to shave off tiny layers of metal in that cutout until it easily slid onto the longerons.


By the way, see that perfect fit? Not just the cutout, I mean how nicely the flange follows the side skin? Well, there's an ominous request on page 24-05, I believe, that asks for fluting the 3 flange segments below the cutout on both bulkheads until the holes in the flange mate the ones in the side skin. I found that weird from the start as the side skins are pretty much flat in that area and so are the flanges. You usually have to flute when something follows some kind of arch.
So I did nothing and just clecoed this one in place to see if there was some fluting required. I didn't see the slightest hint to do anything on either side. Do you?


Maybe Van's did it at the factory. When you look very closely you can see a little dent in the middle of the middle flange. I didn't do that. So maybe this step is not required anymore, just like the one that suggested you should separate the bulkheads from one initial piece. That step was obsolete either as Van's had already done it for us.

Anyway, I clecoed the aft part of the structure together and put the rollbar brace on top. This is how it looked without changing anything about the alignment of the rollbar.


A little closer and taken from the plane of the aft bulkhead...


...reveals that this is pretty straight and doesn't look like it needs any adjustments.

I tried to wiggle it around but the rollbar wouldn't want to move at all, so I figured that this is perfectly aligned and I went ahead and drilled the bases.


The inner holes were a little odd to get at but it was manageable through the opening in the aft bulkhead.
Well, that concluded the day. It was already past 9pm when I took that photo and I left the cleanup of the chips for tomorrow or whenever the next session is going to be.

Rollbar Riveted

From the three options I discussed yesterday I chose the one that I least liked. Why? It's the only one that ensures that the rollbar would be maintaining its structure when taking off and allow me to paint the part separately before putting it back on for final installation.
It was a little awkward to rivet the rollbar while on the fuselage and some of the rivets were hard to get at (mainly because the workbench is now too high) but I managed and prepared everything for the match-drilling happening tomorrow evening.


In clecoed the struts on to push the rollbar back a bit and hold it in the correct position for match-drilling (I hope so at least).
I also took the parts I painted yesterday out of the paint booth and removed leftover spray dust. They turned out pretty nice.


Tomorrow's a gusty, breezy day again and so I covered the whole fuselage with a tarp in an attempt - probably futile - to keep the dust out.

Rollbar Continued

I didn't know how to describe the progress from today as it partly depends on how I am going to continue tomorrow evening. When I came home I started doing some supplementary jobs while waiting for my wife to come home to help me with the rollbar.
Among those jobs was a little counter sinking and nutplate riveting on the bracket that will hold the fuel tank in place as well as dimpling all the nutplate attach holes of the aft bulkhead that will close up the tailcone to the fuselage. Forgot to take a photo there but it's not that big of a task, is it.

I also started spraying the parts for the oil reservoir and the battery and the little platform for the GPS antenna with engine enamel.

Then when my wife came home, we immediately started working on sliding the aft half of the rollbar onto the bases again. That went pretty well as we had done it yesterday as a trial run. The next step was to now take the front half and get this one on as well. That was a bit more tricky - as expected, but we managed to finally get it on with a little tweaking and pushing.


Everything was clecoed into place and now the big question is how to continue?

I could rivet half of the holes inside and out and leave the rest clecoed before match-drilling, or I could rivet all of it and hope that I somehow will be able to get it off for deburring and then back on, or I could fill the rest of the holes with clecos as well, delay the riveting and match-drill now. The big advantage of the latter would be that if there was any trouble sliding it off or back on, I could take the clecos out and just do it like we did tonight. I'm afraid that the riveting will put so much tension on the bases that I might be able to get the rollbar off but maybe not so easily back on.
The structure just clecoed as it is in the photo above is very rigid, stiff and strong, so I'm not worried about the match-drilling being off if I just held it together with clecos.
So I lean towards that no-rivet option right now. Any comments from the educated crowd?

While I was thinking about the best way to do this I kept my hands busy by trial fitting those little struts that will go in front of the rollbar and connect it to the canopy deck. Looks like the fit is pretty good.


It was getting late, so I turned the previously sprayed parts over and sprayed the other side for the parts to completely dry over night. I peeked through "door" of the paint booth to take this sneak peak shot.


My favorite color red was out of stock ...

Addendum: Thinking about my thoughts from last night again I found a problem with them this morning. While it might be better to not rivet the structure before match-drilling for easier removal, it doesn't really help at all when painting it. My intention was to paint it before final installation and riveting it to the base blocks. Without rivets in them this is not going to be doable. I'll have to think more about this ...

Rollbar Fitted

Tonight I just briefly worked on the plane after coming home very late. All I did was to install the rollbar bases (keeping the bolts loose) and slide the aft rollbar that had the strips riveted to it over the bases and see if they would fit. They did fit indeed. I was quite amazed that they even slid on quite easily as I was expecting much more resistance or misalignment.
I won't get sloppy now but this is at least a good sign I guess. Tomorrow evening with the help of my wife I hope be able to put both halves on and start the final riveting process on the roll bar (continuously checking that I can still slide the thing on and off the bases. Once that is done, I can match-drill the rivet holes into the sides of the base blocks and then prime the bases as well as paint the rollbar.

Section 23 Completed

Finally, after almost 70 hours of work, the exhausting section 23 has been completed today!
It started with the installation of the air sickness detectors or air vents as they are usually called. Check Dave's blog if you don't understand why they are also called air sickness detectors. I found that a much more precise term than air vents.


This required some match-drilling. Right side clecoed and ready for the drill bit.
Nothing really fancy about this step only that I had some trouble with the final installation of the vent doors because I didn't precisely remove the material Van's had asked for and so the doors wouldn't fully close due to some interference. It was much more time consuming to remove the material now that the door had been riveted together from its various parts but I managed and so eventually the vent doors were installed.


Then the last step was at hand, installing the piano hinges that will eventually hold the lower cowling to the fuselage. This again required some mach drilling and also some priming of a spacer that sits under the hinge.
This was all quickly thrown together and riveted on, so all you get is the photo when it was completed.


And this completed section 23. Horray!

It was around noon and getting real hot (95F today) but it was too early to call it a day, so I went inside the shop, turned that great A/C on and closed the door.
I wanted to continue on section 24, which is the rollbar installation. The parts were already primed on the inside but I hadn't riveted them together yet because I read in other blogs and in the forum that people had issues following the plans order. It seems that the fit of the rollbar is pretty tight and it is very hard to slide the completed rollbar onto the base pieces on the fuselage. My plan was to complete part of the riveting off the fuselage but leave the two halves separated for now. Try a test fit on the bases and then rivet the parts together while they are already clecoed to the bases. My hope is that by doing that I won't have an issue trying to slide it over the bases afterwards.

So, I started by riveting together the two sides of each half.


And then added the inner strips to the aft half.


That was quickly riveted.


While at it I also added the modifications for the little "reading" light that will get attached to the front rollbar. I also drilled the holes for the wire into the flange of the aft rollbar and put the snap bushing in. I didn't feel like trimming the flange (and ruin the looks) and so I ended up using clear silicone RTV on the inside of the flange to glue the snap bushing in. The side of the hole is so deep that the snap bushing wouldn't snap in without being recessed - or glued in)



The final step was then to open up a pilot hole to 3/8" in the right rollbar attach plate on the fuselage to accept another snap bushing for the wiring. This one can get drilled wider from below and allo wthe snap bushing to get properly seated.


And that concluded another busy weekend.

Side Skins Riveted

Friday I finished the last preparatory tasks for the grand finale. This included painting the longerons where they'd be visible in the interior and some small parts. I sprayed the paint a bit too wet this time (still not sure how that happened) but I was able to just avoid runs.


The paint on the parts was well cured after 16 hours and I continued to aforementioned grand finale, the actual riveting of the skins onto the fuselage.


The longerons were quickly put back into place to receive and hold on to the skins.


See that painful looking arch in my back? It was about then when I realized that I should get a seat to do this.

After clecoing both skins on and setting half the rivets I was ready to start the enjoyable part of riveting.


An hour or so later the rivets were pulled and the final rivets seated.


Left side was soon done and relieved of any blue tape and no longer needed clecos, On to the right side...


Same game but less pictures. After two more hours the task was completed and we now officially have a .... boat!
This completed page 23-06 which took me almost 17 hours to finish.

One Side Skin Ready

I didn't quite finish my secret task list that I had aimed to do tonight. This was possibly caused by all the other things I had to do before getting home quite late. All I could do was to relief the two side skins from their blue vinyl covering and rivet the nutplates in place on skin.


You can't see it in this picture but I deviated from the plans a bit. Van's asked for the nutplates to be installed with those pesky little pop rivets. As all the holes were easy to access for dimpling except for 3 (Van's says two would be hard to get at but I couldn't get to 3), I chose to use AN426AD3-3.5 rivets to install the nutplates and use the pop type only on those 3 holes where they were necessary. Once the pneumatic squeezer is set up for a certain rivet length I find it particularly easier and faster to use squeeze rivets than those little pop rivets.
On the second skin I only got as far as to put the nutplates in place with a cleco in one hole on each of them.

The final task of the day before closing shop was to hang up a motivational picture.


It shows a picture a fellow builder sent me. He obviously got ahead of me and also got a really low-cost engine solution installed, so he'll be flying very soon now. I hung this up to remind myself of the final goal and to keep the competition going... :-)

I hope to finish the nutplates tomorrow evening and maybe to hang both side skins back on the fuselage.

Preparing Side Skins

I didn't quite finish the next task of preparing the side skins but I got almost through. I deburred the longerons and touched up some scratches in the primer (knowing that it will likely get scratches in the same spots again). Then I cut off the little match-drilling template tab on the end of both side skin. That was tricky task as the cut will be visible on the finished plane and so I wanted to make sure that it would be a nice cut.
The tool of choice for a nice cut is the bandsaw but the skin is quite awkward to handle alone and I certainly didn't want to scratch the nice paint job either.
So I had to find a way to get the bandsaw close to a flat work bench.


The bandsaw on a bucket got me within 1 or 2 inches of the height of the skin and that was enough to work with. I got two nice straight cuts out it and deburred the edges of the cut.

Then I carefully broke the rear and bottom edges of both skins. I took my time with that to avoid to accidentally run the tool into the skin which happened with the tailcone skins once. That would have been really ugly. Didn't happen this time.
Then I dimpled the holes around the triangular cutout on both skins.


And before the end of the day I managed to spray some primer onto those pesky little parts that I had overlooked before and that need to get painted before they can be riveted in place.


So I didn't get to install the nutplates in the freshly dimpled holes around the triangular cutout but this will hopefully get done tomorrow night. After that I think I will be ready to cleco everything back in place.