Horizontal Stabilizer - Spars Take Shape

 I apologize for not having any update recently.  I have been hard at work with the school year starting for my kids, the yard work, and work obligations.  I finally got some time to get outside and prepped the Horizontal Stabilizers.  But enough excuses, back to the build.

I finished getting the spar caps cut and deburred.  This wasn't too bad but required alot of drilling once done.  I matched up the parts to the spar and started match drilling.  A lot of the holes were not predone so it took a little bit of time.  I got the flange done, removed them, cleared the piece, and then was able to get the web side finished.  This was a bit tedious but was enjoyable to finish up.  

Spar Cap Match Drilling

After the spar caps were finished up and drilled, I finished out the doubler drilling.  This was rather straightforward, similar to the one on the Vertical Stabilizer.  The one doubler was a bit stubborn to straighten out but I had it near perfectly straight when I finally finished up.   The next part was to cut the horizontal spar attach brackets from same angle aluminum pieces.  This was a bit of a complicated portion as you had to make angled cuts on a piece of metal that is hand measured and cut.  The numbers were pretty precise and took awhile for me to get right.  After getting these done, I had to deburr and round off the edges which took some time.

Measuring the Stabilizer Attach Brackets

 

Bracket cut and marked for drilling.

After the brackets were all done, I was able to finish up the second doubler and drill the brackets.  The brackets get one hole drilled by measurement, and then they got match drilled to the doubler and spar.  This wasn't too hard, but with three pieces of some thickness, I noticed the bit wanted to wander a little.  I was able to minimize it and was happy with the final results.  I utilized a trick from Austin Manke to lift the spar off the table, I had prebuilt the stabilizer stands from a later step while I waited to paint.  This allowed me to lift the stabilizer and rotate it around, making it easier to work with.

Drilling Spar Caps with the Stands holding it up.  Makes it alot easier.

Stabilizer Attach Brackets Mounted to Angle Iron for Drilling

After completing the match drilling, it was to to do everyones favorite part and disassemble and deburr.  It took a little time to deburr all the pieces and holes, but its a rather straightforward task.  Using the electric screwdriver,  I was able to deburr a lot of the holes in short order.  I used other tools for the lightning holes and edges.  It was tough to deburr the spar lengths on the deburring wheel simply due to the length, but it was finished nonetheless.  Then it was on to painting next, but a small project to finish first.

Once I finished the deburring, I was bothered by the way my Air connection was mounted.  The connection drops from the ceiling and is screwed to the wall with some drywall screws.  However, the screws weren't holding well and they were coming out of the sheetrock.  This was bothering me and I didn't want to damage the air connection or wall further.  I ended up heading to Lowe's to get a small board to reinforce the screws.  I picked up some drywall anchors to screw the board to the sheetrock, and then screwed the air outlet to the board again.  The wood was a perfect anchor point and it looks so much better, and isn't pulling off the wall anymore.  Now we are ready to paint.

Reinforced Air Outlet

It took a few days for me due to the crappy weather we have had in New York Lately.  But we finally got some warm weather on Wednesday which was just enough to prime and the winds were calm.  So I broke out my painting racks and went to work.  After I used up my remaining EkoEtch, it was time to get painting.  I really like the Stewarts Systems products as they aren't extremely hazardous like others and simple to use.  I got the painting done in short order and was ready to start riveting after lunch.

Priming  and Riveting the Horizontal Stab Spars

After the Stabs were all dry, we were off to riveting once again.  Luckily, the spar is perfect for squeezing, so I was able to utilize the squeezer for everything.  This provided clean rivets and I was able to get alot done in short order.  I am about 90% done now with the riveting and can move onto the ribs and skins next.  Until next time....

Trailing Edge Cleaned

 So the kids were off from school for a few days and things have been hectic at work.  I finally got around to removing the primer from the trailing edge area of the rudder skins.  A little MEK, a rag, and some elbow grease and it took about an hour to do.  I will definitely not make that mistake on future parts because I don't want to deal with that again.  Now to start back riveting this coming week!

A New Tool, More Priming, and an Oopsy...

 Building has continued as of late and this past week was expected to be in the 50's and low 60's which is totally out of the norm for New York in mid winter.  As such, I made a decision to make sure I was ready to prime before the super warm day yesterday.  I had finished up all of the match drilling and had taken apart the rudder assembly.  The last step remaining was to countersink the trailing edge wedge.  Some builders reported doing this with a drill by hand, but that is a lot of holes to do.  In my cleaveland kit there was a jig designed for a drill press.  This allows you to setup a drill press, configure the countersink cage, and then repetitively drill through the wedge more quickly and efficiently.  And the wedge is kept perfectly at the appropriate angle to drill.  However, I don't own a drill press.... yet.

I had a nice gift card for Lowes leftover from Christmas and decided that it was time to put it to good use.  I went to Lowes and picked up their countertop drill press from Porter Cable.  I already have the band saw and grinder, so it fit in perfectly to my collection.  I got it home, took some time to assemble, and was ready to start countersinking soon enough.  Add in some small clamps and I had the press all rigged up and ready to go.

Drill Press with Trailing Edge Jig

It took me two sessions to do, but I slowly made my way through both sides of the trailing edge wedge.  This part is thin but has an important job of joining the two skins together when I do the final assembly.  I took my time getting the first few holes setup and making sure they fit my test dimple plate perfectly.  After fine tuning the cage, I was off to the races to finish the rest of the wedge.

Nice Countersink Holes

Now that the wedge was finally countersunk, I was all ready to get started priming on Thursday.  I woke up to the temperature already in the high 50's and got setup early.  I used the same setup with my priming racks over the 2x8's.  After getting the kids off to school, it was time to bust out the Ekoetch and start scrubbing.  The etching is very time consuming and tedious work to get done, but its nice cleaning everything up.  Again, its not a big deal to have lots of scratches as this helps the primer bond to the surface.  The unprimed outer parts will eventually be sanded and scratched up when they are ready to paint.  As long as we have no large and deep scratches, we are good to go.  I have to figure out the best way to protect the skins a bit when moving them around the racks.  My racks have chicken wire on top and make some small scratches.  

I had one hiccup or oopsy during my etching session.  One of the last pieces I etched was the trailing edge wedge.  Now doing this was a mistake because we don't want to prime this as it can effect the adhesion of the Proseal when I build the rudder.  But as I was scrubbing the wedge with the scotchbrite, the wedge literally snapped in my hand.  The wedge is so narrow, just gentle pressure caused it to bend and snap.  I now have to recut and redo the countersinking. I am not looking forward to shipping a piece of trailing edge by itself.  I might wait until I order the fuselage and include it in that if I don't have enough pieces.

Snapped Trailing Edge

Priming wasn't too big of a deal.  I gave everything a very thorough stir and made sure to mix it well.  I still like my little detail paint spray gun, but as we get into bigger assemblies, I might need something larger.  I had to replace and refill the spray tank once during the session.  I'd prefer to avoid doing that mid spray if I can.  After everything was done, I broke it all down and got everything cleaned up.  Next week I will start riveting together the rudder pieces for the final time.  This section will be an introduction to back riveting and my first time using Proseal.  I look forward to the new processes.

Vertical Stabilizer - Part 3 of 3

 So I have been busy lately trying to finish up the vertical stabilizer.  The kids went back to school last month and this has freed up a lot of time during the day.  It has given me a good four hours three to four days a week to get this completed, and I had taken full advantage.  So let's jump in.

Deburring and Dimpling - Take 1

After we finished the last section, the entire assembly was cleco'd together, the skins were mounted, and we were ready to start drilling.  I quickly match drilled the skin onto the associated spars and ribs and then started the most fun part, taking it apart to do it all over again.  I deburred all of the rib holes, deburred the skin, and I got ready for dimpling.  I had not used my DRDT yet, so I was excited to bust it out.  I got it setup on my bench and made a small adjustment to it because the dies were slightly off center.

I quickly worked my way through the skin and rib pieces.  They were pretty simple to work through.  One note to future builders, go slow and make sure to go in order.  Don't skip around or anything weird because you will forget one of them and notice it later (I missed one!).  The actual job of dimpling isn't very difficult, it just takes time to finish.  Once that was done, I went to work to completely deburr everything.  Deburring was pretty straight forward, I purchased an electric screwdriver to make it easier.  This tool was a god send, as you could just hold the trigger and move from hole to hole.

First Big Batch of Priming 

After everything was deburred and cleaned up, I sprayed it off with some fresh air to make sure there weren't any metal pieces floating about.  After my first try at priming the rear spar, I made some adjustments to my priming setup.  I got some frames from plywood sheet and bought some metal wire which I stapled over the top.  These were easily laid out over two long pieces of wood on a pair of sawhorse's.  This allowed me to manipulate the pieces and spray easily on my lawn.  I haven't quite figured out what I will do in the winter, but this works for the rest of the year.

My Priming Frames Setup

The priming went fairly well.  I am using the Stewart Systems EkoPrime and EkoEtch products which were well reviewed by Charlie Derk, another past builder in his blog (his blog is linked on my page).  The product is not as toxic as most of the other products out there.  I like this as I don't need to go as crazy and I think it will be easier to spray inside as needed.  The EkoEtch is easy to use, just mix it up in a spray bottle and spray everything.  After a quick spray, you scrub it down, and then rinse it off good.  One issue I had, I hadn't removed the outside skin blue plastic trying to protect it.  During the rinse/etch process, a small amount got stuck under the plastic which I didn't notice.  It discolored a tiny section of skin, but was easily cleaned up with some acetone and corrosion protector.  This won't even be noticed after paint down the road.

Priming Session In The Yard.

After getting the etching all done, I got right to work priming the parts.  The primer goes on pretty easy, I sprayed it all once in each direction then the other way.  It dried within minutes which allowed me to flip over everything and spray again.  It turned out pretty well, but I noticed I had some small sections where it was heavier than others, something to work on moving forward, but everything was fully covered.

Riveting Continues and Skin Riveting

After priming and letting everything set for a day, I got back to work re-assembling the parts.  I started to rivet up the rear spar and get things put together for the final time.  I wanted to try different things, so I tried using the squeezer for as much as possible and then utilized the rivet gun with an old fashioned bucking bar for the remaining sections.  

Aft spar riveting

I had a little issue when I first did the aft spar.  On page 6-4, you beginning to reinforce the aft spar with the VS-1017 doubler and the VS-1012 rudder brackets.  The directions don't really tell you any specific order to put these rivets in.  So I started attaching the brackets first, but I quickly realized I had no way to access the shop head of the middle rivets between the brackets.  So I got some practice removing the four rivets in one bracket so I could squeeze those rivets.

After the spar was completed, I got to work assembling the ribs and riveting those.  These weren't terrible, but there were some tricky ones to buck/squeeze due to the flanges or other rivets.  I think I had two rivets that ended up being unacceptable and had to drill out.  I tried to drill them as I did in my class in Atlanta, but they didn't come out as simple.  I need to modify and grind down the pliers a bit to make it easier to grip the shop heads after drilling.

After I got all of the ribs done, I got to work with the skin.  Once again, the skin takes a bit of maneuvering in order to get things lined up.  After it was lined up, I went cleco crazy to make sure things were lined up.  Get a good worklight that can shine into these parts, this way you can verify the rivets actually have captured the skin and ribs below.  The work light made this pretty easy to do.  However, alot of the rivet checking is done simply by touch with the rivet gauge due to the tight spaces in the stablilizer.

Riveting the skin on the Vertical Stabilizer.

It took me about two days worth of working, but I got the stabilizer skin fully riveted on.  A few were drilled out but it wasn't too bad.  I highly recommend trying to squeeze anything you can, but sometimes the orientation can be challenging.  The nice part of the squeezer is you can setup one calibration and squeeze a line in quick succession.  The bucking bar is a bit more involved and requires more thorough checking as you build.

So I have completed the entirety of section 6 now with the exception of the VS-1010 bracket as I am waiting for a new torque wrench.  I am going to start pulling the parts for the rudder out to get those laid out and prepped.  Hopefully next week we can get that started.

Completed Vertical Stabilizer

Things I learned or points for future builders:

• Get a carpet or something soft to "line" the top of your workbenches.  The skins and parts can get scratched or cut with too much bumping around.
• If you have the space for a bigger workbench depthwise, go for it.  I really wish I had a three foot deep table as parts would fit more nicely on it.
• Organize the parts as best as you can.  The worst thing is looking for a part an having no clue where it is.  I currently have most of mine in the crate, and need to spend some time organizing them better.  I am thinking of totes/bins with numbers on them and a spreadsheet. 
• On section 6-4 Section 5, make sure to do the doubler only rivets first, these are the AN470AD4-4.  Then do the 4-5 that hold the brackets on.
• Figure out your priming methods early and try to have an established workflow before you get to big batches.

Coming Up Next: Section 7 - Rudder

Time to binge watch some youtube for research first :)

First Priming Session.... A Semi Success

 So I decided to try and get started with the right wing since I didn't have the appropriate spar extension piece for the left side.  I got the spar extension and the splice plates all drilled and deburred and got ready to have my first priming session.  I am using the Stewart Systems EkoEtch and EkoPrime products.  I chose this product because its water soluble and easily cleaned up, not toxic like many alternatives, and has virtually no odor allowing me to spray anywhere.  I ordered it direct from the manufacturer because it was cheaper than many resellers.  Note, they took a few days just to ship the item, so it took over a week to receive it.  If you are in a time crunch, order it from one of the bigger resellers.

When I was planning  out my priming setup, I wasn't sure how it was going to work exactly.  I've never spray painted anything with a spray gun, so there is some learning to be had.  I bought a detail gun from Harbor Freight and it was relatively inexpensive.  The gun was easy to setup and easy to use once I got it hooked up.  The primer easily mixed with some stirring, poured through the strainer, and was ready to spray quickly.  I bought a roll of butcher type paper to use as a mat to spray over, however this would end up being a poor choice.  

I quickly got setup and etched the parts easily on my lawn.  I used a watering can as an easy way to rinse everything off and then busted out the red Scotchbrite.  After a good scratching, I laid everything out to get spraying.  I took pictures of the parts so I knew what was what after spraying, I noticed this will take some practice as the primer covers up the markings on the part.

Priming went well and I had no major issues.  The Ekoprime dries relatively quickly in only a few minutes allowing for quick sessions.  I flipped over the parts and got to spraying side two.  I left the parts for a bit to dry and did some other work.  When I came back to remove the parts, I came across my problem.  The primer was still slightly wet and not fully set, so when I flipped it, the primer starts to adhere to the paper below.  The result was some missed/removed primer.

Paper stuck to primer and ripped off when removed.

So I quickly realized my paper setup was not going to work.  I brainstormed and thought about all of the leftover plywood from building the tables.  I thought about what I could use it for and came up with a "paint frame" idea.  I cut out the middle of the plywood and hit up Lowes for some Hardware Cloth.  This is essentially thin wire mesh which comes in a roll.  I then cut down and stapled the mesh to the frame I had cut out which would allow me to elevate the piece off the floor, put it on a hard surface, and not have the issues the paper created.  

My primer frame setup.

Now that I have a frame to work with, I am going to do the left side pieces.  Van's sent me out the replacement part which was actually another right piece.  After a second call, Van's went and checked the batch and found a bunch mislabeled.  A quick correction and another piece was shipped and received this past week.  Now I have drilled and deburred that, we are ready to test the new priming frame out this weekend when its nice out.  I'll report back my results, if it works well, I'll probably cut up two more pieces to have additional frames for larger batches.