Patrick's Sling TSi

Weeks 86-95: Fuselage, firewall and landing gear

It took quite a bit longer than I had hoped, but I finally accomplished the goal of completing the firewall and landing gear so that the fuselage could move off the table and onto the ground. Part of the delay was waiting for the firewall forward kit so I could properly cut the insulation. While waiting on this to arrive I got a head start on the landing gear.

I started with assembling all the wheels, then I attached the front wheel to the front landing gear assembly. There were several parts that attached to this and the main gear that were not coated, so I decided to paint them with a black epoxy paint to match the powder coated parts. Also while I was waiting I put on the main landing gear assembly. Fortunately I had another set of hands available to help get the bolts installed since it required attention both inside and outside the fuselage.

During this time I also received the avionics, panel and final wiring harnesses from MidWest Panel Builders. The panel looks great, and I am looking forward to getting it and the avionics installed. I did notice that the panel will require a notch to be cutout in the glare shield to accommodate the switches. This shouldn't be hard, but its one more task to add to the list.

While getting ready to cut the insulation I noticed my firewall was different than what the instructions showed. It looks like some of the hole locations have been moved, and the factory recommended modifying my parts to match the latest version. They sent me locations and I drilled the new holes as necessary. To cover the unused holes I made some stainless steel blank offs and sealed them to the firewall with a high temp gasket. I also found some grommets that I liked better than the kit version to seal the water hoses as they pass through the firewall, they have steps with multiple diameters to better seal to the hoses.

The last step I did while waiting on the firewall forward parts was match drilling the fuselage top skin so it could be attached to the firewall and side skins. One thing I realized while doing this is that the components this attaches to do not need to be dimpled or countersunk since the fiberglass is thick enough for the rivet to sit flush when it is countersunk. I had to flatten out some dimples and fill in the countersunk holes I had already done in the cowling attachment strip.

When I got the firewall forward kit and the replacement engine (which was undamaged this time), I quickly got the needed parts attached to the firewall and marked them on the template to be cutout. Then I used the template to cut the insulation With that installed I permanently attached the parts that had to fit around the insulation and started installing the motor mount. I found when doing this that some of the bolts called out in the manual were too short, they did not have any threads sticking through the lock nut. I ordered some replacement bolts and new nuts to fix this.

With the motor mount on I could start attaching the front gear. Had had quite a bit of difficulty with this. After struggling with it for a couple days I realized that the half grommets were hand cut and not completely square to each other. I had to match them up in pairs that fit together better and install them in the same orientation. That let me get all the plates that secure them to fit in place, they still took some mechanical encouragement and I had to use a drill to get the holes cleaned and lined up.

While all this was going on I also took care of a couple other tasks that needed to be done. I installed the cabin water heater (and later found out I have to replace it since it does not have the correct base plate). I also drilled the holes for the static ports and shields and installed the ports using the same sikaflex adhesive/sealant I used on the canopy. I started to install the shields in the wrong orientation, but caught it before I got too far. I have not riveted those on yet since I might wait until after painting.

With the front gear on, I went ahead and installed the main gear as well. I ran into another bolt issue, this time 3 out of the 8 bolts in the kit were labeled incorrectly and were too short. I just got replacements for those from aircraft spruce. I also discovered a very slow leak on one of the main wheels. I ordered a replacement inner tube and have that replaced now, I did find a leak in the original one.

The assembled fuselage at this point is getting somewhat heavy, so I decided to use loading ramps to get it moved off the tables. I set those up on cinder blocks with the front wheel secured to another pair of them. With the weight off the tables, I pulled those out of the way. Then I held my breath and started rolling the wheels down the ramps. It turned out that the cinder blocks tied to the front wheel made a perfect anchor to slow down the process of rolling down the ramps. I was able to keep it controlled on my own (although some more muscle would have been a good idea).

Now that the fuselage is on its wheels and a little more accessible I started working on interior details. I got the retaining rings for the controls sticks drilled and rivet in place, then I got the aileron cross link installed between the two sticks. But in that process realized I don't have all the pushrods I will need. I shouldn't need the ones I am missing until final assembly, so hopefully I can get them before they slow me down. I also realized that the wiring harness does not match the original plan of putting the GMU 11 in the right wing. I will have to rework the harness to move those connections from the tail section harness to the wing harness.

I think the next steps will be to get as much of the wiring in as I can, then start working on the interior skins. There is a lot of work left, but it is very rewarding to see something that really looks like an airplane now!

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