Right Wing Spar on the Stand.

The factory is slowly but surely coming together. Even with all of the work I have done so far to get the stands ready, ther are still about 8 more holes to drill in the bottom half of the stands. Once I get a feel for where they need to be positioned, I will attach the support angles that will be clamped to the bottom of the trailing edge to ensure that the wings are as straight and untwisted as they can possibly be while I attach the wing skins.

Here is a pic of the left wing spar on the stand with the ribs re-attached to give you an idea of how they will go together.

Then it was on to the right wingtip attach bracket. I'll just show the sequence of photos with no elaboration, since the process was much the same as it was for the left wing tip rib. Clamp - drill - debur-attach.

Still a little tweaking to do on both spars to get it all level, but you have to wait until you load it up first with all the parts. Next steps:

1. Finish deburring the rivet holes on the underneath side of the of the left wing spar
2. Drill and debur all holes for the right wing spar main ribs
3. Make a template for the position of the 3/4" hole I need to drill to feed the conduit through the ribs, drill and debur all those holes, as well as the additional 5/8" holes near the front flange of the ribs I will drill for running additional wires and the AOA and air lines from the pitot tube back to the fuselage. Then yet another set of 5/8" holes in the rear of each rib on one wing only, to accept the wing tip Bob Archer navigation antenna wires. I have given up on the idea of a wing tip comm antenna - just not practical and they don't seem to work very well according to other builders who have tried this. So I will install my 2 comm antennas on the bottom of my fuselage, in between the main landing gear wells, and hope for the best when it comes to communicating with folks while on the ground.
4. Scuff, clean, finish deburring, and prime all ribs
5. Start pounding rivets for the main ribs. The spars will come off the stands for this. I will either be clamping them to the work bench or to the table - I have not decided which yet. Perhaps one spar on each to speed the process a bit.

On the last point, I spent some quality time searching on VAF last night, and I ran across a post that I had actually read before, that is like finding gold in terms of the critical info that one must possess in order to attach the wing skeleton together correctly. Some of the key gotcha areas for this task are trying to buck rib attach rivets without damaging the precious wing spars, and properly securing the work for riveting. Clamping and taping certain areas for protection is absolutely critical here. Lots of folks have trouble with rivet sets vibrating off the AN470 rivet heads causing smilies or worse, and this is mainly due to inadequate clamping of the work.

My biggest area of concern was with the rear spar. I was not sure how I would secure the work if I had already attached the ribs to the main wing spar first, which is also a must do item. This post pretty much explains it all. I will use the squeezer on the rear spar, so securing is a little less of a concern when I get to that point, but it still needs to be done. The information in this post is absolutely 100% essential to ensure a successful wing skeleton assembly. Every tip given in this post is one to live, eat, and sleep by if you want to do it the right way, as told by those that have been there before.

Every once in a while you run into gems of information like this on VAF and in other builder logs that is worth every penny it takes in time and effort to find it. The rules are simple - Secure the work - bucking buddy if possible so both your hands can be on the gun and the rivet set, etc., etc. Great stuff. Hopefully I will be smart enough to follow all this great advice when the time comes. So far so good.

Enough for now. I hope to be priming a lot of ribs over the next weekend.

A Young Eagles Flight Adventure - - NOT!

Editors Note****** I revamped this story just a bit to make it easier to read and corrected some obvious grammatical and spelling errors. Apologize to my readers for that. This version should be much better.

It turned out to be a pretty nice airplane work session over the weekend, despite getting nailed with tons of snow Saturday evening into Sunday. Before I cover the details of the build, there is something else I thought might be worth mentioning that happened to me early Saturday morning. It concerns a matter of aviation safety, and I thought that other pilots might benefit from it.

I was planning on flying Young Eagles Saturday morning at KFTG for the second YE rally of the year. YE flights have become so popular that the chapter rallies that are held each month are booked at least a year or more in advance, and EAA Chapter 301 cranks out about 50+ first flights for kids during each and every rally. I feel privileged to participate in this event, and even moreso when I get to fly.

Anyway, since I do not yet own my own airplane, I have to resort to renting an airplane from the local flying club. One thing that really concerns me is how extremely expensive renting an airplane has become compared to when I first learned to fly in 1980. I am frankly a bit shocked at the state and age of equipment that exists in most flying club fleets these days, compared to the grossly out of proportion rental rates that they charge. Personally I think it is just another example of American greed at work here, but I digress.

Chalk it all up to another of what I would rate as my top 5 reasons for wanting to build and own my own bird. The aircraft that are currently available for rent are a mix of old and new, and the equipment and avionics in these older model aircraft is pretty lacking. The problem that I see is that they are charging expensive rates for newer aircraft of the same model, and they are also basically charging you the same rate for an aircraft that, from an equipment/avionics perspective, does not even come close to what the newer airplanes have. I can't believe that the cost of insurance, maintenance, and fuel are making these older airplanes just as expensive to fly as the newer ones. In fact, I think what is really going on is that they are using the older aircraft in the fleet to help cover the actual cost of renting the overly expensive newer models. This is nothing short of robbery IMHO, and is  truly a sad state of affairs for those wanting to learn how to fly today.

Anyway, I had scheduled a C-182 for the flight on Saturday, and the weather was perfect, except for it being extremely cold and prone to frost in the morning. Gee - sounds like deja vu from the first time I did this in November of last year. So I arrived at the airport (KAPA) early in the morning before the club opened. I had scheduled an early morning departure so I could arrive at KFTG by 0745 local for the briefing. The club places the aircraft books and keys in a lockbox and you get the combo the day before so you can retrieve it without waiting for the office to open up.

So I  opened the lockbox, and my airplane book is nowhere to be found. A couple of folks with access to the office had also shown up early, so I was able to sneak into the office, and sure enough, found my airplane book sitting neatly on the shelf. Not to worry yet - perhaps it went down for maintenance, but I would have expected a note or a phone call had that been the case - but I received neither. Anyway, I retrieved the airplane book and headed out to do the preflight so I could be on my way.

I opened the airplane up, and alas - it was almost starved of all fuel. This is not uncommon for a C-182, which is a prime cross country airplane, having flown several hundred hours in them during my former years as a Civil Air Patrol Search and Rescue Pilot. Still no problem - called the fuel truck and the fuel was on the way. Then I turned on the Master switch to lower the flaps and began my preflight - so far so good. Everything else inside the cabin checked out, or so I thought, so I then proceeded outside to walk around the airplane. As I reached the tail one of things that is routinely done is to check for freedom of movement of the control surfaces. This is done by physically grabbing the elevators and such and moving them gently from one extreme to the other. If everything is normal, you hear and feel nothing other than the smooth operation of the counterbalance springs, and perhaps some slight noise from the hinges that attach it to the HS. Unfortunately for me, I hear this very loud squeal and a very distinct grinding noise, all coming from inside the cabin. I returned to the cabin to move the controls this time to see if I get the same noise. Sure enough - the co-pilot side control yoke was starting to bind on something, but the pilot side still felt OK. Both yokes are joined together behind the panel so that either of them can control the same control surface.

This became an instant deal breaker for me. Sure, I could overcome the slight binding with normal control pressure, and the noise, while disturbing, was not ultra-overpowering to me - just annoying enough to catch my attention. The problem was, and my thought process was, what if it gets worse after I become airborne - what then? What if they totally freeze up during a critical phase of the flight? Even more importantly, what if I encounter this problem with a Young Eagle and their parents onboard for their very first small airplane flight? I was not willing to even remotely consider that possibility. So the decision to abort became relatively easy when I took the well-being of my passengers into account.

Having had this grinding noise type of problem before, I new that it had something to do with the mounting bracket or bearing on the copilot side controls. Unfortunately, since the pilot and copilot control yokes are mechanically joined together, they both need to be working properly or else you may have a problem.

By now I recognized that I was starting to experience something that I have taught countless other pilots to recognize over the years. I call it the "3 strikes and your out rule," but it is also better known as the "catastrophic chain of events" in most post mortum NTSB accident reports. No matter what you call it, it often times leads to an undesireable outcome for a pilot and their passengers. The premise is that most aircraft accidents are not attributed to just one single factor, but are usually comprised of a series of linked events that lead the pilot further and further toward a devastating outcome, driven by the series of actions or inactions taken by the pilot. Pilots must learn to recognize when they enter into this situation, and then take the necessary action to break the chain.

Strike 1: The airplane book was not available, making me late and pressuring me ever so slightly to hurry up and get going. There was a possibility that the airplane had been grounded without my knowing it. Action - I chose to preflight anyway and then further assess the situation after that was done.

Strike 2: No fuel in the airplane - more time wasted - more pressure to hurry, but this was also expected, and was of the reasons why I arrived early enough take care of it.

Strike 3: Grinding noise and binding of the control yoke - Ok -  this was not something I was willing to compomise on. If it don't work right, and the potential outcome might be very bad - don't risk it. I broke the chain right here.

And then came yet another strike. Strike 4! It was as if it was affirming my decision not to fly, or at least that is how I took it. I needed to raise the flaps back up and secure the airplane so I could return to the office. But when I actuated the switch, nothing happened. No upward travel at all. I then thought I could try to lower the flaps all they way down and then back up to see if that would work, and it did, for a moment anyway. The flaps came back up to the point where they had about another 10-15 degrees of travel remaining, and then the flap motor cut in and out several times until they finally retracted to the full up position.

I returned to the office, reported the problems to the dispatcher, who by this time had opened the office, and then I left for home. The one thing that disturbs me is that the airplane had flown the day before, and I can almost assure you without a doubt that the control yoke was exhibiting the same behavior on that flight,  but they flew it anyway.

It is decisions like this that face pilots on every single flight, no matter if it is an airliner or a small GA airplane, some of the decisions that must be made are very much the same. I wanted to jot down this experience in my blog to hopefully benefit any fellow pilots that may read it.  I wanted to reaffirm to others that there is absolutely nothing wrong with saying that you probably won't get to go flying today... Better to live and fly another day than to die and never get the opportunity to do it again. Extra vigilance must also be applied when flying unfamiliar rental aircraft that may be in less than "mint" condition.

I was proud of myself for making the decision to stop the ever-progressing chain of events that were unfolding before my eyes, but still frustrated about the whole experience, and the realization that I was not going to get to participate in this month's YE rally. This is the reality of being a pilot -sometimes you just have to say "not today."

Instead, I chose to view this experience positively as follows:

-I went home and started working on MY airplane - so the day was not a total loss at all.
-I am using these experiences as strong motivators to finish my project someday. I am so sick and tired of dealing with flying rental airplanes, and schedules that don't match mine, and airport security crap, etc., that I am more than willing to continue the long and expensive process to one day own and operate an airplane that I built with my own two hands.
-I may have saved someone's life by taking the action that I did to ground the airplane and demand that it be repaired. That is perhaps the most rewarding feeling of all, and in the end is really what all the preflight preparation is all about.

The moral to the other pilots out there:

 Don't forget about the reasons why you perform every step of the preflight checklist, and how important it is to do it right, and to pay attention to what your senses are telling you. Part of the problem is that flying has become so reliable these days that we rarely have to face a problem serious enough to force us to make an outright no-go kind of decision.

So if this sort of thing happens to you, recognize the events that are unfolding around you, evaluate your situation and potential options, understand the risks for taking each option, and make the correct decision - even if the decision you will have to make is to stay on the ground.

Fly safe, and all you builders out there don't forget to fly every once in a while!

Left Wing Spar Ready for Mounting on the Stand

Lots of stuff to talk about today and lots of pics to share. I basically managed to finish my attachment bracket for the end rib of the Left wing yesterday. As with so many things about this project, it was the process or the journey I ended up taking that was the most satisfying thing about getting this seemingly simplistic thing done.

The first problem I had to solve was how to properly position the attachment bracket against the end rib so that it would allow the spar to sit as level as possible across the entire length of the wing spar.
I knew I needed to get the angle bracket flush op against the rib in just the right position, which is basically at a point where the bracket sits flush up against the web of the wing spar. The only problem with this is that this bracket is atached to the outside of the end rib, where no wing spar web exists. So how do you position this bracket in exactly the right position oif you cannot lay it down flush against the wing spar web?

After thinking about this, I had a moment of deja vu. I was sure I had been in this position before, just could not remember the specifics. Anyway, the solution was simple. The last three outboard ribs of each wing are W712s, the only difference is that the 2 inboard ribs are "L's" and the end rib is a 712 "R". This just dictates the direction of the flanges on each rib, but the ribs themselves are essentially the same part with the same dimensions. This means that I could take the W712R end rib and move it inward to the inboard location of the W712L rib, cleco it in place, and whaaalaaa, I now have a healthy amount of wing spar rib to butt one side of the attachment flange up against, while the other side is flush against the end rib.

The whole point of this exercise to position the bracket in the correct place on the rib so that I can match drill the 1/4 inch holes in the rib for the bolts that will attach the bracket to it. IN previous posts I had already drilled the mounting holes in the steel angle. All I am doing now is transferring those holes to the correct location on the rib.

A pic is worth a thousand words:

I clecoed the rib in every hole, then slid the attach bracket in place, clamped everything down, adn match drilled the mounting holes:

The wood in the above pic is used as a backer for the drill bit to help prevent the aluminum of the rib from getting too rough when the bit penetrates the other side. This is thin drilling aluminum 101.

Next is a pic of the whole thing clamped into position and ready for drilling. I clamped down the spar onto the table in addition to clamping the parts together. I have had enough of wallowed out, uneven holes die to improper securing of the work. Remember to clamp EVERYTHING securely before you drill or rivet. Any movement of the parts during either of these activities usually gives less than desireable results.

Remember to keep the clamps from rubbing or vibrating against any of the parts. Pad them if necessary or use a large enough clamp to ensure that it does not interfere with the parts.

Let the drilling commence:

The tooling hole is somewhat close to the bolt hole that I drilled on one side, but this is perfectly fine. Vans also states in their plans that drilling these mounting holes will not compromise strength of the rib, which also tells you something about how not to worry too much about drilling additional holes for wire runs as necessary. I removed the rib and the bracket, then deburred the new mounting holes in the rib, and reattached it to the correct location at the end of the spar. Then I bolted the atach bracket in place on the end rib. One down and one more to go for the right wing spar!

Then it was time to trial fit everything on the stands and do a general check for level.

This first pic shows the overall mount with both sides clamped to the stands:

Next is a series of pics showing the mounting bolt orientation of the mounting bracket and the clamping arrangement to the wing stand. I will most likely drill additional bolt holes in the wing stand and attachment brackets once I am satisfied that they are in the final position I need for assembling the wing skins.

 

 

A couple of important notes about this.First, remember that certain disimilar metals that come into contact with each other can cause corrosion and other problems. Not remembering if Steel and aluminum "play nice" with each other or not, I decided to err on the side of caution. I placed a piece of gorilla tape over the side of the attach bracket that contacts the rib, and I will do the same thing on the inside of the rib shown above where the mounting nuts and washers are located. The ribs will be completely primed, but I still want to do whatever is necessary to avoid any other means of introducing corrosion.

 

Next, I used standard 1/4 inch HD hardware for this assembly. The only problem with this is that the cut washers are exactly that - stamped from a press, which leaves a rather nastly burred edge on one side of the washers. I deburred them as best I could, but in the end realized that the easiest solution for this was to ensure that the side of the washer that is smooth (one side is very smooth, and the other is rough) is what is placed against the wing parts. The other rough side will rest against the bolt hardware.

 

Next is a pic that shows the clearance gap between the angle on the stand and the mounting bracket on the rib- which is the main reason that used the 2 inch wide angle. This clearance is needed for the wing skins that extend beyond the edges of the end rib to provide the mounting surface for the Wing Tip, I have pently of clearance here, and may end up moving the brackets a little closer together once I see how much clearance I actually need when the outer wing skins are on.

 

 

And then a couple of pics of the Root side of the wing spar. I used 6" C clamps for this and a block of 1x2 wood to keep from marring the thick steel spar bars.

 

 

 

The above series of pics serve as confirmation that I definitely have sufficient space between the wing stands to position the wing spar on them. I can move it up an inch either way and still have sufficient room to rest the spar on the stands. This is what I expected and was worried about based on the uneven garage floor and all the shimming I had to do.

 

And finally it was time to strap some levels across the spar and see where things are at. I can't really make any rush judgements about anything until all the ribs and the rear spar are clecoed to the main spar, and the sag is taken out of the middle by using a jack stand or similar solution. For now, I was pretty satisfied with the results - everything was "mostly" level.

 

 

 

I seem to have a slight twist in the spar as I get closer to the root end, and I also found out that the spar bars are NOT milled to exactly the same specifications from bottom to top. They are both uniquely milled to different specs to provide different specific levels of strength and support, and therefore you cannot just lay a level across the bars and expect to get a level indication. That said, the mounting flange of the wing spar where they will be inserted into the fuselage center section and bolted in place is perfectly level.

 

So it was good to get one of them ready for additional assembly. Now I need to wash, rinse, and repeat this process for the right wing spar, which I hope to have done by the end of this weekend. But alas, another round of snow is expected tonight.... 



Wing Stands almost done - sort of....

Over the weekend I made pretty good progress on the Wing stands. As shown in this next pic, the support angles are now installed on both sets of stands. I am pleased with the way these have gone together. The Wing spar shown is actually sitting up side down from its correct resting position.

I have one more major step to complete before the spars will be ready to rest on the stands. This is the attach plate that must be affixed to the W712R end rib that serves as the outermost rib of the entire wing. The wing tip will be attached to the top and bottom wing skins adjacent to this final rib. One thing I learned from several other posts and discussions with other builders is that many do not take into account the position of the wing skins at the outermost edge of the wing. The skins will overlap the outer rib and end of the wing spar by about 3/4 of an inch, and a lot of folks attach the outer wing rib right up next to the main support bracket on the stand, only to find out later during installation of the skins that they need to reposition the spar or find some other solution to allow the additional room for the over-hanging wing skins.

So hopefully I have thought this through far enough in advance to know that I needed to obtain a large enough piece of angle to provide the necessary clearance between the end rib and the support angle bracket on the stand. The solution is a 2x2x1/8 inch piece of angle that will will be cut to a 5 inch length. One half of the angle will be positioned on the forward part of the W712R Wing rib adjacent to the wing spar web, and the other half of the angle lays over the top side of the support angle bracket. The 2 inch wide angle should provide enough clearance for the overhanging wing skins. Again, pictures of this will speak a thousand words, but here as an example once again is a shot of Sean Thomas' arrangement for this, and mine will be somewhat similar:

From the above pic I think that Sean will also have this problem when the time comes, because his rib is a bit too close to the support angle. Note the thick piece of angle (looks like 1/4 inch thick) that is bolted to the rib on the top left of this pic, and how it overhangs the main support angle bracket.

Next is a shot from the top side showing the rest of the angle that attaches to the main support angle bracket. The theme here is that only one side of the wing spar actually rests on the support angle on one side. The other side is affixed to the support angle bracket via an additional angle bracket attached to the end rib. The trick to all of this is getting the attachment angle properly positioned so that the spar can be maintained in a level attitude.

I have recently read some posts from other builders who have complained about the skins becoming slightly misaligned as they try to fit them together. I can't help but think that it has at least something to do with not maintaining as level an attitude as possible for the wing spar, which causes the skins and ribs to slant one way or the other. So the real critical part to this hole thing is to get the attachment angle positioned and bolted to the end rib in the just the right spot. Note the torpedo level in the pic below as well. You not only need to be level across the width of the spar, but also along the entire span of the spar.

And finally the pic of the bolts that attach the end rib to the attaching angle.

Meanwhile, back to a couple of shots of my build. It has been a very very long time since I assembled any of the actual airplane parts together. This is always one of many - "wow this is really cool!" moments in the build when you start to see the smaller parts become bigger airplane parts. The next step after getting the wing stands done is to cleco the main wing ribs to the spar and drill the attach holes to final size. It is also a preliminary check to see how well your ribs align perpendicularly with the spar. ON the right are the ribs that folks will be stepping on top of to get into and out of the airplane, and on the far left is the end rib discussed previously.

Lots of little steps remain on the way to completing each wing, but the fixture part of this process is almost over. Getting into another cold spell around here so I decided to take a break from the shop tonight. I hope to have both attachment angles positioned on both end ribs so I can proceed with the rest of the rib prep that is required before I can finally pound some rivets.

More Small Victories

One Wing Stand down, one more to go, and then a few other minor details, etc., etc.

Working last night and again tonight, I was able to finish fabricating the threaded rod brackets and drilling the remaining holes in the other side of Wing Stand # 1. So the supports are essentially done for one wing stand. this first pic of the threaded rod brackets after I drilled one 1/4 inch hole and one 5/16 inch hole for each bracket.

Next is a series of pics showing the completed assembly of one support:

I just noticed that the store label on the outside of the support angle gives an optical illusion of the angle being slightly bent in the above photo - wierd! I will remove this later to keep it from paying tricks on my mind as I build the wings.

With that side done, it was time to finish the other side. First was the bottom side hole - same as the first side - 9.25 inches below the mounting hole for the support angle. I measured and marked the spot just as before, and drilled the hole on the first side of the stand. This next pic shows what I think I tried to describe in earlier posts but may not have done so very clearly. Pics are worth a thousand words. THis shows how I measured the precise location of the first hole so I could transfer the dimensions over to the other side with reasonable certainty that they were the same. The straight edge is clamped so that it serves as a hard stop for the tape measure.

I transferred the dimensions over to the other side of the stand. This time the hole lined up almost perfectly. I then drilled the other 1/4 inch mounting hole in the angle bracket, and it was time to assemble the hardware for that side.

And then the final touch. To prevent the rough steel angles from scuffing the wing spars during assembly on the stand, I placed Gorilla tape over the tops of both angle supports. The spar will be clamped in place on one end, and the outboard end of the wing will be attached to the opposite support angle via yet another support angle that will be drilled and mounted to the last wing rib, and susequently to the top of the attached support angle bracket. Again, easier to see than to describe.

Anyway, feels good to complete the brackets for one wing stand. Now I just have to measure and drill and mount the supports for the other stand. Since tomorrow is Valentines day, adn the following day is my local EAA chapter 301 meeting night, I may not get this done until this weekend, but it will get done. You keep celebrating the small victories, and one day they all add up to one huge victory celebration when that first flight is entered into the logbook and engrained into your memory forever. Still looking forward to that day, whenever it may be.

Threaded Rod brackets, Cont'd.

Tonight I managed to brave the cold long enough to cut the remaining 7 bracket angles from the 1.5 x1.5 x 1/8 inch thick aluminum angle I used as a backer plate when I drilled the nut plates for the wing spars. I needed 7 more for  a total 8. This is 2 per side, 2 sides per stand, and 2 sets of stands. I was able to find enough width in between nut plate holes to satisfy the requirements for each angle bracket. Most of them are between 1 1/8 to 1 1/4 inch wide, and this is fine.

Here are the raw blanks after I measured and cut them on my band saw. I really love my full sized band saw. The standard wood blade that it came with does a fine job cutting medium to heavy gage aluminum like butter. Do not use it to cut thin aluminum sheet, though.

Since the angle was a bit too long on both edges for my needs, I trimmed both ends another 1/4 inch, and ran them over mt scotch brite wheel to debur the cut edges, which are measured and marked in this next photo:

Then I measured both sides for the center point, and took the washers I am using for the 1/4 inch mounting bolt and the 5/16 inch threaded rod, and drew the pattern for each washer on the angles. Each bracket will have one 1/4 inch hole on one side and one 5/16 inch hole on the other side.

The finished "prototype" is in the foreground in the above pic. All I need to do now is drill the holes and finish trimming each one. Then all I need to do to finish up is drill the holes in the remaining angle supports and wing stands and I will finally be ready to support the wings on each stand. Man what a process this is. It's alot of work, but well worth it in my opinion. I can't wait to put it to the test.

Fabricating and Positioning Threaded Rod Brackets

This weekend I managed to locate and drill the hole on the opposite side of the wing stand post that secures the angle bracket to the wing stand. I also started the process of fabricating the brackets that will receive both ends of the adjustable threaded rod that will brace the support angle that holds the wing spar. I need to make 8 brackets, and there is a bit of measuring and fabrication work involved, as usual.

The process I used to lcoate the matching hole on the opposite side of the wing stand was to clamp a straight edge across the wing stand so that could get a precise measurement from a another ruler as to the exact distance of the edges of the drilled hole from the edge of the wing stand, as shown below:

I placed the edge of the second ruler up against the straight edge to get an exact measurement. Then I  measured from the top of the wing stand to the top and bottom edges of the hole. Now I have all 4 measurements needed to draw the matching lines on the opposite side of the stand as shown above. I marked and drew the reference lines as shown after reclamping the straight edge across the short side of the stand as shown above. Then I center punched the stand and drilled the hole. The test to determine if I did this right was simple -  if I could continue to push the drill striaght through to the hole on the opposite side, I did it right. Luckily it worked pretty well, and the holes were aligned as expected.

Next came the brackets for the threaded rod supports. I used 5/16 inch threaded rod, and 1/4 inch hardware for these. I also used remnant from the 1.5 x 1/8 inch aluminum angle that I used to drill the nut plate holes in the wing spar flanges. I cut the angles down to 1.25 inches. After making some calculations to allow for bolt head and washer thickness, I determined that probably not more than a 1 inch piece of angle is needed, but I wanted something a bit wider to help counteract any tendancy for the angle to distort or become compressed when the weight of the wings is applied.

First step was to determine where to locate the hole in the stand. I used the pythagorean theorem to determine this. That formula is a squared plus b squared equals c squared for a right triangle. the "C" value is already determined, and this is the length of the threaded rod, which makes up the hypotenuse of the triangle that is formed by this arrangement.  it is 12 inches long. The other measurement that is known is the B measurement. This is 6 inches from the location of the wing stand attachment hole in the support angle to the hole in the support for the threaded rod bracket. That leaves only the A measurement to solve for. I wanted to find the measurement that would allow me to use the stock 12 inch length of the threaded rod without the need to cut or debur the ends of that. It turned out at 9.25 inches left a C measurement of just over 11 inches. This would leave approximately 1/2 inch on either end of the threaded rod to allow for adjustments to keep the wing true with no twist or distortion. SO the measurements of the triangle formed by this support are 6 x 9.25 x 11 inches.the reality is that there is much more thread to use for adjustments because the attach points for the rod are well forward of the center mounting hole of the bracket. This will become more clear with more pics.

So I did my best to mark and drill 2 more holes in the same wing stand that were 9.25 inches below the first hole. this did not turn as well as the first set of holes as far as alignment of the holes on either side of the stand was concerned. I think the drill slipped a bit, and so the bottom bolt is at a slight angle compared to the top bolt. Regardless, I think it will work fine.

Here is the pic of the first hole, again after carefully measuring the location in reference to the forst bolt hole above:

And the second hole on the other side:

And then came the bracket:

It has to be tapered to accept the threaded rod that connects the angle support to the wing stand. I will have more pics as this all comes together. Still a lot of work to do, and 7 more brackets to fabricate. It may take me the majority of next week to finish everything for both Wing stands, but it will get done.

Drilling holes for the support brackets

Tonight I managed to carve out a small chunk of time to start the process of mounting the support bracket to the wing stands. These angle brackets will act as the shelves that will support each wing spar. Last night it rained and then froze and then snowed, and so it was bit too cold to work in the garage. Tonight it was not quite so bad outside, so off to work went.

This process is much the same as any other process on this project, if you want to do correctly. It involves a lot of measuring, positioning, clamping, leveling, and drilling. Gee that sounds awfully familiar for some reason!

The steps for setting the support angles went something like this:

1. Drill the first support bracket mounting holes on the 2 inch center that was previously marked on each support angle. I am using 1/4 inch hardware for this, so I drilled a 1/4 inch hole. I used a center punch but the drill bit I used still wandered a bit. It is for this very reason that I wanted to drill the holes in the support angles first, instead of drilling the holes in the wing stands. That way I can use the final hole of the bracket to match drill the hole in the wing stand later.
2. Determine the height of each support bracket- I settled for about 48 inches above the floor of each wing stand and made a couple of marks on each stand accordingly
3. Clamp one of the support angles into position. Use a small level to verify that the support bracket on one end is truly level.
4. Determine what the "true" level height should be for the bracket on the other wing stand as follows:

Remember that my garage floor is anything but level, and so simply measuring 48 inches for each stand and clamping both support brackets in place is probably not going to really give me a level-sitting wing spar. Why all this fuss about leveling the wing spars? Simple. Even though the ribs and skins are prepunched for an exact match, once you start clecoeing them to the ribs, gravity will still have a tendency to pull on the entire assembly to the point where you may end up with some slight mismtaching of the skins. Better to ensure everything is truly level so that the skins will want to fall straight down perpendicular to the wing spars, and the ribs will do the same.

To resolve this I used some fishing line and several line levels like the ones shown in the pic below.

With the help of my son we stretched the fish line across the wing stands with the line levels in place to check for true level between the stands. One end was placed directly on top of the clamped support bracket on one side, and the other was stretched across to the other wing stand, and a mark was placed on the short side of the wing stand along the fish line, after verifying that the line levels were truly level.

This is where it gets a bit comical. I knew that I may have to adjust my marks on the stands by perhaps one or two inches, but when we used the yellow line levels to check for level, I mistakenly thought that the bubble needed to be inside the black lines in the middle of the level. This resulted in an offset of about 6 inches from one stand to the other. Really, I need to set one support bracket 6 inches higher than the other one on the othe stand??! Not believing this for a second, I decided to switch to the more normal looking blue line levels, and of course, this time I only need to adjust the marks on the opposite wing stand by about .5 inches. That made a heck of alot more sense. My floor is bad, but not "that" bad!

Then I finally figured out what I did wrong. These yellow levels display several marks that show different offset values from level, so that you can set specific grades for drainage for things like driveways, sidewalks, etc. I should have set the fish line so that the edge of the bubbles on these levels just meets the line marked 0, and the rest of the bubble is on the clear side, opposite the side with the marks. SO whne you want the bubble to show "level" it is not located in the actual center of the level. What a messed up tool! Just goes to show you that no matter how seemingly insignificant a tool is that you might use for your build, you must know how to use them properly, or you may risk really end up screwing something up. I re-measured everything again with the yellow levels just to satisfy my curiosity, and of course the marks ended up being about the same as with the blue line levels. What a relief.

5. I used a square to carry the previous mark around to the inside long edge of the wing stand. This is the line that the support bracket must align with to keep everything level.
6. Then I clamped that bracket into place using two bar clamps on either side of the 1/4 inch hole that I previously drilled. This allows me to use the hole in the bracket as a pilot hole for drilling the first hole in the wing stand. I used some boelube and the cobalt drill bit to match drill the hole for the bolt that will be inserted into the wing stand and support bracket.

And this is where I called it a night.  Next step will be to accurately measure the location of the bolt hole on the other side of each wing stand so that it lines up with the holes that I drilled tonight. There are several ways to accomplish this to ensure that the bolt holes are straight across from each other, and I will explore which method I want to use and post more about that tomorrow. I do not trustmyself to keep the drill straight enough to continue drilling the hole on the outside of the stand by using the hole on the inside as a guide. I have very poor luck with free-hand drilling holes like that. They always end up a little off. So I will take my time here and do this right.

Closing with some pics of the work done tonight: