tailwheels

Unintended Adventures

Tag: Stabilizers

Assembly

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On March 20, 2018

In S-20

Airplane building took a big hit this school year. The plane is in a hangar 50 minutes away now and the Fall semester was full of the usual projects and assignments to appease the professors.

Since the last update I’ve been working on mostly assembly tasks. The one thing that has kept me from positing an update is that I haven’t really finished any of those tasks. Sometimes due to a lack of time to finish and other times because I couldn’t find the right parts or I ran out of some of the more consumable parts (rivets and nylon lock nuts specifically).

But, things are still being accomplished. I’ll start from the present and work back to the last update.

I finally got the gear legs finished how I wanted them and installed onto to the plane. This involved installing the brake lines and fittings for the gear as well. I ended up buying new tubes with 90 degree stems on them because I could never manage to install the straight stem tubes in a way that would not interfere with the axle. I know it was a problem on my side, but I couldn’t quite figure it out. Another exciting part of assembling the main gear was not realizing I installed the brake caliper mounting plate in an incorrect orientation until after I had installed both wheels and installed the cotter pin. This was because I also failed to understand that I needed to install the brake caliper before installing the wheel since I no longer would have access to the back side of the mounting plate once the wheel was installed. Fixing that mess will take an hour or two I’m sure and I’ll be doing that on my next workday (Hopefully this coming Saturday).

I also managed to final install the tailwheel assembly and the horizontal stabilizers. The tailwheel assembly wasn’t hard, but my bushings between the blocks around the tail spring were too long and needed to be shortened slightly. Once that was done, I set to tightening the tail brace wires and rigging the stabilizer. I tried my best to complicate matters and be engineer-y about it to find a specific value that the tension in the wires needed. After bugging RANS and some A&P friends it was determined that there is not a specific value called for and “feels right” was the needed tension. Oh well… They seem to be tight enough and fall in line with what other similar brace wires I’ve dealt with before (Cub, Champ).

I managed to bolt on the left elevator and it is ready to be connected to the elevator push pull tube. One of my hinges was tweaked, but I put a wash in between the hinge and the stabilizer and it does not seem to be causing any excess friction. I’ll continue to monitor that hinge and check for any indications of excess stress since tightening the nut did apply what I consider more than normal force onto the hinge. The right side elevator is awaiting some more rivets to arrive so I can finish up the trim tab.

Onto the trim tab. I completed the assembly onto the elevator and had few issues. My assembly wasn’t perfectly straight and I needed to force one side of the tab maybe a 1/16″ forward in order for it to capture the bolt from the elevator. I also had to shave some material off of the most forward rivet on one side of the tab because it was interfering with the elevator. If any other builders read this and had a problem similar to this or no problem at all I’d be interested in hearing from you. I don’t have a ton of paint on my parts, but that and the fabric could definitely be contributing factors. The rivets are on order, so hopefully the right elevator can be mounted this weekend.

My list of things to do for the next work day are installing the brakes, get the control sticks mostly installed, and drill the stops on the elevator push-pull tube. Looking forward, once I have the push pull tube stops in place, I can place the aft baggage compartment and finally get it back off the ground.

Till next time…

(25 h)

Plane Stuff

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On October 22, 2017

In S-20

It’s been almost 3 months since the last update. I’d like to say I’ve gotten a lot done, but it hasn’t turned out that way. Lots of school obligations that I didn’t entirely plan for manifested and here we are almost to November.

I have gone to work on the plane, but just nothing ground breaking to report. We did head out to the hangar yesterday though and got the horizontal stabilizers mounted and all of the tasks required to get to that point. It’s always fun to start something and be able to finish it in the same day. Getting the bolts to go through the stabilizer and fuselage bushings was an exciting activity, but just needed a loving tap from a small hammer to coerce the correct behavior. 🙂

I brought home some steel parts to get powder coated before I completely install the stabilizers since there are some tabs where the tail wheel spring mounts to. I’d like to get them to the powder coat place this week and have them ready to go for the next time I go down.

Since the last update we have also worked on the mounting brackets for both the flaps and ailerons and they are complete and ready to be installed.

We started to also fit the wingtips up and still have some work to do on that front.

The engine monitor has been neglected somewhat as well. In the beginning of the semester I acquired a few more components for it, but I need time to get some soldering done so I can start testing and integrating them. The new stuff will be a power supply/regulator so it can be hooked up to a 12V supply. In addition, there is a small battery that will provide power after the plane’s power is turned off so that the engine monitor can shutdown properly and avoid corrupting the file system.

(30 h)

Whirlwind

By

On July 26, 2017

In S-20

Summer is slowly coming to an end and things are getting crazier for us. Moving to a new place in a week so I can finish my engineer transformation, finishing an internship, starting classes again, and going to Oshkosh all in the next month.

The plane is painted (mostly)! There are still all the exit covers, inspection plates, boot cowl, and some trim colors on the doors and rudder, but all the major assemblies are painted. Covering and painting is about all we did on the plane this summer and it was a busy task. I don’t care for painting and am glad that it is mostly finished. The rest of it will be an exercise in finding the space and equipment to do so, but it shouldn’t be insurmountable.

The plane has also been moved. After 2.5 years of half living in a garage and the other half in storage, all the airplane parts are finally together again in a hangar. It looks much cooler in a hangar and it’s even neater to see everything together. The only annoying part is that there are no hangars available nearby where we are moving to, so it’s about 50 minutes away from the house. There is an airport 10 minutes from the house, but even after a year and a half on the wait list, I haven’t risen to the top. Looking forward to getting some things actually assembled this coming year and making it look more like an airplane finally.

That’s about all the airplane stuff for the past two months. I could write a small essay on painting issues, but nothing has to do with the paint I used. A lot of operator learning/error. If you want to hear more, let me know and we can discuss a few things.

As this is posted, we have completed the move. I’m still busy being an intern for another week and a half and then I’ll join back up to start the new semester.

Oshkosh was great. We saw a lot of cool things, got to play with some avionics, and visited with friends.

(80 h)

School’s out for summer

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On June 4, 2017

In S-20

Finally moved in back at the real house and classes are done for the Spring semester. Three more semesters left before I can be a real boy again.

I finished the other half of the stabilizer I started covering 4 weeks ago, so now I just need to cover the elevators and then I can start working on the tapes and the patches. I don’t mind tapes and patches since they seem to go much quicker than covering entire pieces.

(Everything above this was written a month ago when I thought I was ready to push out an update. Everything below is a collection of stuff I have done since then.)

Today is the culmination of a task that has taken us nearly 1.5 years. The actual time from the cracking the first bottle of glue open to getting everything ready to get to the paint shop was one year, five months, and twenty-one days. I started in December 2015 and finished today, June 2017. I never envisioned it taking this long, but When I started I was still at home, taking classes at the local community college. No more than 3 weeks after I started covering is when I went back to the big university to begin the Aerospace Engineering journey. It was hard to work on it during the school months since covering takes quite a bit of set-up and clean-up. It’s hard to just do an hour of covering because not a lot really gets done.

So, this past week my wife and I had a week off from work and my busy intern life to relax and catch up on everything we have been putting off for the past nine months. We thankfully got to work a lot on the plane and put in probably 50 man hours over the week to get the covering finished. It was a long process, but it was awesome to get that chapter closed this past week. It has been an open task for so long that I thought we would never get done with it. I enjoy covering and there is an artistic aspect to it which is nice, but I think I will need to space out my covering projects by at least a couple of years :-).

On to the details. Most of the work we had to do was putting patches and tapes onto pieces we had already covered. The only pieces that weren’t completely covered were the elevators. I ran short of fabric again and had to order another two yards. In the end I had to order an additional eight yards of fabric on top of the fabric I received from RANS. Come of this I know I would have needed regardless, but some of the extra fabric probably would’ve been avoided with more careful planning and layout of the parts.  On the flip side, the fabric is relatively cheap and probably a lot less stress than coming up short after thinking you laid out the piece properly.

I’ll list a few things I noticed while covering that may be of some interest to others embarking on this journey.

Since it is what we did last, I’ll start with the elevators. These weren’t hard, they just had a lot of sides and two curved edges that made things a little interesting. For the curved edges, my only advice is when laying down the fabric, make sure you have a decent bit of excess so you have enough to shrink the fabric to make the curve look pretty without and wrinkles. Mine are pretty ragged because it took me a while to get my technique down, but I wasn’t planning on winning any show awards. I started shrinking at the middle of the curve and then worked my way outwards. For the tapes in these areas, I tacked the tape down on one side of the curve and the pulled the tape from the other end to get the tape to follow the curve better and it helped to get the tape to lay down along the curve. I then tacked the middle of the tape down along the entire curve. After that, I started shrinking the tape from the outside of the curve and worked my way to the middle while alternating on each side of the curve. This is what seemed to work best for me, but maybe you’ve got a better idea on how to do it?

The last trick to the elevators is the stitching. It’s all straight forward except the stitch that is only on one side of the elevator since the bottom side has a plastic exit ring for the trim servo. I put the bottom fabric piece on and then the top piece of fabric on so the top would look better. If you do that, the stitch becomes a little difficult. The problem is that the tube you are stitching around is about the total amount of space between the 2 layers of fabric. I didn’t have a fancy curved needle that could make that bend, so we improvised. I did put a slight bend in my needle for the process to help aid it. First I went through the top of the fabric and out the bottom inside the trim servo exit ring. Then after I pulled the needle out of the bottom, I went back through the same hole and then out the other side of the plastic ext ring still on the bottom side. Then I pulled the needle completely through that hole and then sent the needle back through that hole to pierce through the top layer of fabric in line with the other top side hole but on the opposite side of the tube we are trying to stitch. I didn’t care about the hole inside the exit ring since we will cut that out. The other hole I made in the bottom part of the fabric wasn’t bad, but I put a tiny circular patch over it anyway to feel good. It worked great even though it was sort of round-a-bout. If anyone has another way they did it, I’d like to hear it.

The other pieces didn’t prove to be too much of an issue. I didn’t shrink the door fabric much past 250 (except where I had wrinkles), but ironing the tape edges and patch edges did shrink it a little more than I initially did, so we will see soon enough if that means I get the opportunity to make new door trim pieces (YAY!).

If anyone has any questions about the covering process, feel free to reach out to me. I’m not an expert, but I probably have made most of the mistakes you could make for a first-time covering. In case anyone is only reading this post, we used the Stewart Systems covering products. I’ve enjoyed them and I haven’t had to wear a respirator and I did a lot of covering on the kitchen table during the winter.

So what’s next? I’ll kick off the painting process this coming week and if I don’t slack off and don’t upset the person helping me paint, I hope to have them done by the end of June (that’s my hope 🙂 ).

I need to definitely get them done before July as we will be moving and I’ll lose access to the folks who have been helping me a lot with the plane over the past two years. I did find a hangar after a few hiccups with the local airport. It’ll be an hour drive away, but it was better than the storage unit alternative.

I probably won’t have too much to report on the next month since I’ll be focused on trying to get the paint on, but I’ll try to get some pictures and a quick update on what they look like throughout the process.

Hope to see some folks at Oshkosh this year!

(80 h)

 

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