I started out by trimming the ends of the shear web flush...
And sanded them smooth..
I then sanded the shear web..
Since I did not build the "per plans" 2x4 jig, I did not have a drill jig to get to the embedded nut plate. Instead, I had previously made paper templates to locate the threads of the lift tab nut plates. To use the template, I first marked the canard's centerline.
I then positioned my template - lining up the edge of the paper with the centerline..
I now had the exact location of my threads...
I made small dimples to mark the locations of the threads...
Using the smallest drill bit I had available, I drilled the first hole and prayed to the canard Gods to PLEASE not hit metal. Yes, I realize this was extremely risky, but I had confidence in my template..
After the drill bit went all the way through to the backside foam core without hitting any metal, I knew I was spot on! I then began to expand the diameter.. a little at a time with larger drill bits... leading up to 1/4"... going to a depth just above the metal plate insert..
I then used a 1/4" flat-end mill bit to get the last few thou of fiberglass and expose the thread underneath... notice the tape to make sure I did not go too deep..
With a little bit of patience, the thread was exposed. I spent a few minutes removing the saran wrap I used to plug the thread and protect it from epoxy..
Once I removed the saran wrap plug, I test fitted the first bolt..
With one bolt in, I then used the CLT lift tab as a template to mark the remaining two holes...
Using the same procedure I explained above, I eventually got the rest of the bolts in... and then repeated it for the other lift tab.
Now to prep the leading edge cores...
Eureka CNC was kind enough to drill the locating dowel holes from the aft cores to the leading edge cores prior to shearing the leading edges off. The idea is to place ten 6" dowels into the aft core, and then using them to align the leading edge cores back in there ideal location.
To do this, I first had to drill through the shear web and expose the 10 holes. Since I use Aeropoxy, it was relatively easy to see where the 10 holes were located...
Drilling through the aft end would enlarge the hole in the foam. So instead, I drilled through the front end - only drilling through the fiberglass - not into the foam. I figured it's ok to make the fiberglass hole slightly bigger than 1/4" since I want the dowel to align itself with the foam hole - not the fiberglass hole.
To make the dowels, I purchased two 4ft 1/4" diameter dowels from Home Depot... I cut them into 6" lengths. To make it easier to insert them into the canard, I wanted to sharpen the ends. To do this, I stuck them in my drill and set my handheld belt-sander upside-down on my table..
With the belt sander running... I spun the drill and angled it onto the belt sander...
And vuala! Ten 6" dowels ready to go...
I then dry fitted them into place...
In order for the leading edge to lay flat, some foam needed to be removed to make room for the lift tab pads and bolts...
I hovered the leading edge over the pad and marked the 'ramp' locations on both ends...
Notice I marked where it needed to be flat, and how long the transition ramps needed to be...
I kept struggling with "how do I hold the leading edge upright while I work on it?!"
As I looked around the garage, I realized I had the perfect solution right in front of me! I could use the foam scraps that the cores came in as a mold to hold them in place - it just needed a little bit of trimming...
Vuala! A perfect leading edge mold to hold it in place!
Now to mill off some foam..
In hindsight, this was completely overkill! I could have simply used a knife to trim this off!
I then made a deeper pocket for the bolt heads to go into... and used sandpaper to ramp the ends for a nice transition...
Test fitting the leading edge... looking great!!
With the leading edges trimmed.. it was time to bolt the lift tabs in place - permanently!
The original plans say to use "AN4-7A bolts with AN960-416 washers"... the Roncz canard plans say to use "AN4-7A bolts with AN960-10L washers"... Hmmmm but -10 washers are for AN3 bolts.. I'll assume they meant to say "AN960-416". Now the question becomes "L" or no "L"? Well, we are talking about a 0.032" difference - so the important thing is that we have the proper thread engagement.. so let's measure it!
To do this, I took a paper clip and made a small 90-degree hook at the end...
I inserted it down one of the holes and hooked it to the bottom of the K1000-4 thread insert. I then marked the paper clip indicating the top of the fiberglass 10-ply pad. Notice the tiny red tick mark on the paper clip...
I then used my digital calipers to measure the depth...
I then used it to compare it to the AN4-7A bolt, using a AN960-416 washer and the lift tab. Hard to see in this picture but I had 2.5 threads exposed.. good enough for me!
I then prepped the hardware...
Mixed up some flox and applied it to the lift tab and onto the 10-ply pad surface...
I then installed the lift tabs in place... first gently using a regular socket wrench...
And then used a torque wrench to torque the bolts to 50 in-lbs as indicated in the plans.
Look at that flox oozing out... perfect!
I then cleaned up the excess flox... and let it cure overnight.
The next day, I was ready to install the leading edges. I mixed up some micro and covered the dowels with it...
And inserted them in place..
I did this for all ten dowls. I used two fingers (perpendicular to the dowels) to make sure I had at least 1.5" to 2" sticking out...
I then covered the aft wall of the shear web with micro and spread it out evenly...
I then positioned the leading edges into place...
Looking good! But now how to weigh them down in place?!
Ah yes, I had the "molds" that the cores originally came in! I cut them in half and placed it on top of the leading edges - this provided a flat surface to put heavy items on...
Here is a good shot showing how the "mold" wraps around the leading edge and bears down on it..
Just have to let it dry and we can move on to the next step!
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