Ever since Oshkosh I've been keeping super busy working on the plane and less work on the actual documentation work.  This has created a bit of a backlog of work to get caught up on - and these next few videos go back into early July.

As you can see from the first video here I'm still working on finalizing as much of the interior of the fuselage that I can so I can get the side skins on.  The idea was to get all of this done so I could reach in from the side of the airplane than down into the fuselage to do the work.  As you can see from the video I got the side skins on and the firewall attached.  Once those were attached it was on to working on the landing gear.

I did an independent video based on the Beringer wheels and the differences between them and the Matco wheels.  Now it's time to work on getting them together.  Wandering off the beaten path presents it's own unique challenges for building.  Some of them are easy, some of them are hard.  I would chalk the different landing gear being up there on the harder of the items.  To do this I needed to first have a new shim made to match the square one, but this time in rectangle to match the axle for the wheels.  It wouldn't be a big deal except for the fact that shim also had a bevel to it - which I didn't have the tools to make.  So I found a local machinist who has spent his career doing machine work.  He made quick work of these bevels - and they matched perfect.

I had to backfill the open holes for the 1/4" bolts used for the Matco mount with a fiberglass epoxy resin.  This resin is amazingly hard but also easy to work with.  I patched up the open holes to refortify the landing gear structure.  After that I created new holes for the 3/8" bolts for the Beringer wheels.  I also backfilled an open cutout no longer necessary because of how the Beringer wheels attach to the landing gear.

To make matters even a bit more interesting - as you'll see in the pictures and I believe the video the front nose wheel yoke is built for the Matco wheels.  The bolt to hold the Matco wheels on is obviously designed for that wheel - but the Beringer has an axel made for it's wheel - and the Sling supplied bolt is slightly bigger than the opening for the Beringer axel.  This presents a new issue on how to match the two up.  Again - back to the machinist to discuss.  Showing him what I was trying to accomplish with the Beringer Axel, Matco bolt and yoke he understood the engineering problem.  He was able to bore out the Beringer Axel to within 1:1,000th of an inch tolerance to allow for the Matco bolt to pass through the Axel.  There is still a fair amount of material on the Beringer Axel and zero play between the bolt and axel.  So the axel won't spin on the bolt thus causing wear.  

While waiting on the parts and gear to finish up I wrapped up the throttle quadrant.  The problem I ran into was with the mount for the valve I purchased for the breaks.  The factory supplied mount wouldn't fit snugly, so I called up a friend from work who dabbles in 3D printing.  He gladly took it on and created a mount for the brake line which if you ask me is actually more secure than the factory one.  If you're at all interested in going this route, he has the file online at ​https://cults3d.com/en/3d-model/tool/sling-tsi-parking-brake-panel-mount.  

I may be missing a few things in this post, but the videos are most current.  I'm trying to catch up on my documentation to be more current with the end of September (as I'm posting this) - stay tuned for more fun!

This is the progress pics for the Beringer wheels installation.

I generally do my write-up on each months post after I've got the videos done so I have to go back through and review them from time to time.  The distance between when the initial recording started (mid-June) and now is quite a bit to recall.  

The work has continued on the wiring and at this time it's reasonably close to being run and near completion.  I'm not tightening anything down at the moment because I'm sure there will need to be some additional adjustments as I move through the cabin.

I've got the rear fuselage skin cleco'ed into place at this time.  I am going to need to make one more run on the left hand side of the skin to adjust a few more things with the wiring.  I also think I have the ELT antenna sorted out.  I think if there is anything that bugs me a bit is the instructions up to this point are great, but when it gets to wiring, Sling is pretty hands off and expects Midwest to pick up the slack.  They do a great job and everything, but even the plans on that are bit of a "well, however you want to do it"...   At Oshkosh I looked at 3 different low wing TSI's and there were three different ways to do the ELT... anyway - I think I have it sorted out.

Other than the writing - it was back to (wait for it...) you guessed it control tube work.  It still needed a bit of TLC, so I was back at it again.  I think I've got it there now and things move along a lot better.  Of course now I found a few I've probably shaved off a bit much so I'll have to replace those going forward.  That part shouldn't be too hard to resolve as they are the controls on the outside of the control rods.

With the control rods seemingly in good shape I moved onto closing in the sides and getting the firewall installed.  One thing for sure is putting the actual physical structure of the airplane, ribs, skins, etc. is super satisfying.  It feels like you're getting something done.  It's the small stuff that feels like you're not making much progress.  The sad part is I'm pretty close to being done with the big stuff and going to be spending far more time on the minutia.  

I got the main landing gear installed for the most part.  I have to remove one side so I can get the final rivets done which I missed thinking I could sneak them in after the gear was in place.  Oh well, it's an easy fix with the bolts quick to remove and put back in.

​Next up on the schedule is to get the wheels on the airplane and then I can move stuff around a bit easier.  I'm looking for getting the wings tidied up.

I'm finally getting around to doing the written portion of the documentation on the build videos.  Over the course of the  previous month we got the seats built/assembled with only some minor issues needing additional work.  I also spent a big chunk of my time working on the fuel lines and getting them set so they would work with the other finishing pieces.  I had originally intended on having a single line run from the side firewall to the fuel selector position.  That process was proving to be very difficult with the needed bends in the line.  So I switched up things a bit and changed the fuel lines into segments.  This obviously introduces some potential issues where leaks could occur, so I will have to make some conscious effort to test and ensure these joints are sealed.

I received all the avionics this month as well.  The wiring harness, panel, avionics, etc, so it was time to start getting the wiring installed.  Yeah more things to learn how to install!  There are no real solid instructions on how to do these steps, so I hopefully won't wear out my welcome with questions with Midwest.

I had the EAA Chapter 43 Technical Counselor Jim Sutton over again to review my work.  Overall he's been very helpful in making sure my work is on par with where it needs to be.  There's some subjective areas since this is only the second SlingTsi being built here in Colorado and Jim hasn't seen one of these before.  The control rods are especially tricky to get right because you have to remove/install everything to test it, and if it isn't done well enough (ie: not sticky) then you get to do it all over again.

My father-in-law Harold and I got the front and rear seats put together over the past month.  They aren't terribly difficult other than getting the rivnuts lined up correctly so they receive the screws just right.  I'll have some cleanup work to do on those when I get closer to installing them.

I also had to fix/repair a wrinkle in the right rear fuselage skin.  Until starting this project I didn't know you could manage minor wrinkles in metal by "rubbing them out"... I basically found a dent repair kit at a local auto shop which contains some steel "plates", I put down some tape to protect the skin from any sort of deep scratches and then rub out the wrinkle.  If I do it right you can't find/see the wrinkles after that.  It saves some time/expense in getting a new piece of skin in.

Beyond that, all of my focus has been to get as much in the center fuselage of the plane done before putting the side skins on because once those go in I will be working from the top-down vs. the side-in.  The side-in is obviously an easier process.

Next steps as of right now are to finish up the wiring issues, finish securing anything else inside the front fuselage, get the side skins on, the main landing gear on, wheels on the landing gear, firewall so I can get the main nose wheel on and then the wings finished up.  Still lots to do.  With Oshkosh coming up at the end of July I'll lose a few weeks there but hopefully have things moving along quickly here come August.

As I’m writing this as evident by the date it’s mid-May. The video and the work covered here is a bit of a look back over the work accomplished to this point. I’m focusing a lot of my work during this time on the flight controls and reading ahead to try to get as much work done ahead of putting the side skins on. I’d rather spend a little extra time here where I can work on the center portion of the fuselage with the skins off than after the skins go on and I’m then needing to spend my time working with my head upside down working on the items in the airplane.

My father-in-law Harold has even over lending a hand on the misc items needing to be put together. The throttle quadrant, front and rear seats has been something he’s been assembling with some help from me. I’m going to send my throttle quadrant off to Midwest Panels to have them powder coat it with their treatment. I wish the throttle quad had flush screws instead of screws that are raised. That’ll be a project for another day but not right now as that’s something I’ll stick to the plans on.

I also have spent a fair amount of time working on running some aluminum fuel lines over the rubber ones as the rubber ones need to be replaced in five years. It would be nice if Sling had an upgrade option for this as an offering but I get why they go with the rubber lines. If I can’t get the aluminum lines to work the way I want then I’ve been in conversations with a company about building some teflon lines. The cost for the Teflon over the aluminum is probably about 4x the cost… but honestly having.a fuel line leak in the cabin isn’t super high on my list.

Once I can overcome these items that consume a fair amount of time to get right I’m hoping I can move along quicker. As of today I received all the items to complete all the avionics. I am hoping to hear about the firewall forward being delivered here soon as I really need the fuel selector to be able to install the fuel lines all the way. It hasn’t been revealed to me yet as to why some of the order of materials are delivered because I would think you should get everything to complete the center portion of the fuselage before the side skins go on. Hopefully I’m not building myself into a corner somewhere.

I called today to get the technical counselor out to inspect the rear fuselage so I can work on getting the skin on that part of the plane. That would be another good milestone. I just want to make sure that section is 100% correct before I complete that phase. Once it’s on, it’s on.

I do have the part to resolve the wing hing issue which prevented me from completing the flaps and ailerons. Once we wrap up the seats on the bench, we’ll get the bench cleared off so we can get the wing up on the bench, skin removed, hinge replace, skin re-attached, wingtip back on, flaps/ailerons aligned and the fuel tank attached. Then we’ll attach the other fuel tank and we’ll be complete with the wings and I can focus everything onto the fuselage.

Much of April was spent on working on the flight controls.  More than I really anticipated really.  I think I'm pretty close on where things need to be as far as the fluidity of the controls.  I did join the rear fuselage and the center fuselage together as part of this process.  I was concerned about additional binding that might occur with the addition of the side skins and other twisting that may go on when joining the center fuselage and rear fuselage together, so before I riveted the controls into place I moved everything off the bench with the side skins on.  I think I'm in good shape here.

The upgrade brakes/wheels and stainless steel lines arrived during the past few weeks, so I'm ready to get those installed - and looking forward to it.  But I'm tidying up loose ends here and there.  It took me several passes to get the writing in the rear fuselage just right but I think I've got it set now.  Next up I need to finish up is the pitot static line, the comm wiring and ELT wiring so I can close out the rear fuselage.

Also, it's important to note that I plan on engaging and having over the local tech counselor to review my work prior to closing out anything major like the rear fuselage.  After all - I only want to do this once!

I also had the first go at fitting the side skins on.  They go on quite well and I look forward to riveting them on, but until I have all of the items needing done prior to this I'll endeavor to get as much done as I can before I complete that step.

The project as a whole doesn't "feel" like it's moving as quickly as before - simply because I think the parts I'm working on now are much more nuanced in nature.

With regards to the wing hinge needing to be replaced.  I have the part here now.  The plan of action going forward is to get the fuselage onto the wheels.  I'm using the bench time to complete items like assembling the seats and the throttle quadrant.  Once I've got those items done and the bench is cleared off I'll get the wing back up there to remove the skin, fix the hinge and put it back together.  Once that is done, the bench can be pushed back against the wall where it normally lives when not building an airplane.  This will allow for more room for the plane, now (when it's done) being on wheels with the engine mount on the front end.  This will make the overall length too long to fit in the garage without it being at a diagonal position.  So that's going to take a bit of doing to finagle this together in the space of time needed to do the nose wheel.

Best laid plans eh?  Wish me luck.

It's been quite a month and it's not yet over.  This month I have the luggage door pretty much together.  I can't complete it entirely until the top skin is attached and that won't happen for a few months.  I got the main floor together and attached to the wing spar.  The rudder pedals are installed with the only thing left there is to attach the rudder cables to them.  I also started working on the control toque tube installation.  That's going to take a little bit to accomplish as I'd like to have them set in there and operating very smooth before finishing that up.

Over the next week I will get that finished up and then start mating the rear fuselage to the center section.  If all goes well the plan will be to have the main fuselage on the wheels and off the bench so I can finish up the work on the wings.  The hinge replacement left CA today and will likely be here next week with all the supporting parts.  Once I finish the hinge replacement I will be able to finish getting the fuel tanks onto the main wings.  Just to refresh, the hinge for the right wing was the wrong hinge (bent left instead of right), so I have to remove the bottom skin, change that out and then reattach the skins.  Not what I was looking forward to doing, but it should go pretty smoothly.

It never gets old.  A couple of weeks go by and it doesn't feel like I've made much progress and I come back to look at these pictures and video and I see how far I've come.  

At this time the right wing has the wingtip removed and when the hinge comes in I'll be ready to swap that out.  The workbench is quickly not being able to support the fuselage, so it'll go on the mains here soon.  That will be quite the milestone to reach.

In looking at some of the pictures here the wiring isn't in the final location after making a couple of test runs on the install.

My nephew Nathan and my father-in-law Harold were over again to help with the build.  Having the extra hands has been super helpful.  As the weather gets warmer I should have the garage door open a bit more and it will be more pleasant to work in the garage.  

Today I took delivery of the finishing kit... but I moved that straight into storage as I don't have the room to get into that right now, but I do need to get the inventory done on it to make sure it lines up with everything they indicated shipped.

At this time the only things needing to be delivered will be the avionics, the interior kit and the engine... I gotta get back out into the garage and keep going!  :D

I hit a very significant snag this week which was a bit upsetting.  The right wing inboard flap hinge actually was the wrong part - even though I am very certain it was labeled as a right wing part.  I don't have proof of it, but I am not sure how it got by my wife and I during that part of the build.  I discovered this when I was preparing to align the flaps and ailerons on the right wing and could not get the aileron to attach without a very significant amount of bending - which then of course pushed the aileron into the flap.  So it very clearly was very wrong. Because of that, I reached out to the factory and they confirmed there isn't anything I can do beyond replacing that part.  Of course this is discovered only after the top skins and wing tips are installed.  To correct it their recommendation is to remove the wing tip and top skin as well as the rib with the hinge on it so I can replace the hinge.

I also was chatting with a SlingTsi builder in Germany who ran into the same issue but caught it before they got too far into the wing build.  

Now before we all go throwing Sling under the bus - I do realize they have a few thousand parts to get right.  This is my first build and I just need to do a better job of scrutinizing the left/right parts like this.  I can assure everyone the mistakes I've made along the way are lessons well learned and if I wind up building another plane the experience will definitely go a long way into the next builds.

​The other challenge I'm having at the moment is the fuel tanks.  I just can't seem to nail down all of the leaks.  My biggest fear was that I had leaks forward of the front plate in the fuel tank which is nearly impossible to access with the backplate on.  The methods of doing some basic pressure testing and soapy water just wasn't giving me good results and it was a bit messy.  So this past weekend I broke down and filled them up with water which helped tremendously to identify the leaks.  I'd rather do water than fuel because, well, gas tends to light on fire.  Water just goes down the drain and is far less expensive.  I'm fairly confident I will have the tanks resolved here in the next few weeks.

The other fortunate part is because I've been struggling with the fuel tanks it delayed putting them on to the wing and given my issue with the hinge for the aileron it saved me a bunch of rivet removal as I most certainly would have had that attached prior to the flap/aileron work.

At this time it was a bit of a barn dance over the past weekend of moving wings off the bench and onto the storage rack and the fuselage onto the bench.  I'm going to continue working forward with it while the fuel tanks cure on the pro seal and the parts for the right wing come in.  Once that arrives I'll blast through the right wing as quickly as I can. The tanks will be done by then and the wings will be completely finished up.

I also found out today my finishing kit has arrived in Torrence CA.  That will be enroute here in the next week or so.

Things feel like they have slowed down, but I'm working on just getting lots of the little odds and ends for the control surfaces finished up and after that it'll be 100% focus on the fuselage.

That feeling of euphoria over how fast building is going has slowly waned away as I work on the final phases of the fuel tanks and wings.  It's actually pretty easy to put some ribs together and attach skin to it - but when it comes to the finer details like fuel tank sealing, wing tips... you know - stuff you absolutely MUST get right the first time, it starts to drag.  Not that getting ribs and skin together doesn't have to be done correctly, that part of the assembly is more of just repeating the same task over and over again.  The fuel tanks and wing tips - those are new areas for me, so let's slow down a bit.

Fuel Tanks:
I got the remainder over the rivets and finished (what I thought) sealing the second tank.  The entire tank assembly process has been of concern because there is no room for error.  One tiny leak could lead to weeks of trying to work around or through it.  And guess what - I'm there.  I tried to do a water test - the water in the line leveled right out.  It's not supposed to level if there is pressure in the tank.  So I cobbled together some items to do a balloon test... the balloon inflates a tiny little bit but won't expand.  So that's going to be this weekends job is to suss out the leaks and resolve them.  

 Wings:
I have both of the leading edges outside of the fuel tanks on the wings at this time minus one of the leading edge stiffeners is a bit shorter than the left wing.  I've had a few email exchanges with technical at Sling in South Africa and they have given me the go-ahead to use the one I have.  I didn't *think* it would be an issue, but I wanted to confirm before I riveted it in place.  The edge that mates up with the fuel tank just won't have about 1/2" of extra stiffener going from the leading edge into the fuel tank.

Other than that, the rear fuselage is riveted together and once I can wrap up the fuel tanks and wings I can move onto the rest of the fuselage.

Two other big milestones that aren't terribly interesting to watch in the video, but I spent a full day tearing down all five of the shipping crates.  The trash man picked them up today.  I needed to get that done here soon because in the next few weeks I expect to get a call from TAF with my finishing kit and possibly interior.  I was down to just one shipping crate for the fuselage over at my father-in-laws garage.  He was perfectly fine with leaving it there, but I was getting to a point where I was needing all these little odds and ends to assemble the fuselage and often I was needing to dig through the shipping container to find that one part.  That involved emptying everything out, looking around a bit, finding it and then putting it all back.  Everything left is in the basement in my house now, and it's spread out around the room so I can quickly identify it when the time comes.

The other milestone is I got a rack build for the wings to live on when I get the wing tips onto the wings.  When the wingtips go on, the jig the wings sit on now won't work any longer.  I got the rack from Aaron Stampa who is now flying his Sling and reworked it to what I thought worked best.  Four 8" heavy duty casters from Harbor Freight and some extra 2x4's from Lowes and it looks ready to do the job.  There is still some question as to how I'm going to handle the wings on the rack - but I think it's going to come down to some heavy weave fabric or carpet or something like that.  I have to go do a bit of browsing at the store to get that dialed in.  If you look at the pictures here, you'll see the rack in the end.

Anyway - short update this time around.  The video will have more commentary.  Hopefully by the end of the month I'll feel confident about the state of the fuel tanks and have that behind me.