CHAPTER 10 – CANARD
Chapter 10 done – 02/15/2009 !!!!
Step 1: Trimming the foam blocks and cutting the cores
Step 2: Making lift tabs, inserts, jigging cores, laying up the shear web, and installing lift tabs
Step 3: Jigging and bonding the canard sections together
Step 5: Applying the bottom skin
Step 6: Installing hard foam blocks for elevator hinges, the upper spar cap, and the upper skin.
Step 1: Trimming the foam blocks and cutting the cores
Kent helped me cut the cores at his house. It was not as difficult as I initially thought, but definitely takes more than one person to do.
I did not take any pictures of the core cutting itself, but here is a picture of the result. Once we were done cutting the cores, we wrapped them back in the foam that they came out of and taped it up. It was a tight fit to get all the foam back in my car. I had some pieces on my lap as I drove back home.
Keeping the cores wrapped, keeps them safe
Step 2: Making lift tabs, inserts, jigging cores, laying up the shear web, and installing lift tabs
I bought my lift tabs from the Cozy Girls. These are well-made parts and highly recommended.
For some reason, I was very concerned about getting the 2x4’s for jigging cores just right. I used fishing line and even a laser to make sure that everything was perfect. There is no need though to get this precise, as long as the cores themselves are perfectly straight.
There is no need to try to
get this precise.
Lined the cores up with fishing line down the center and two other reference points
Installing the lift tab inserts was pretty straightforward. It took me a few times to re-read the plans though to make sure that I have it all correct. I was deathly afraid that I would not be able to line everything up after cure. It worked out fine.
The shear web took a long time to do. I made sure that I was ready with all the cloth (rolled up) and peel ply before starting the layups. I put silicone in the holes of the lift tab inserts to ensure that the epoxy stay out of it. Doing the layups themselves were not terribly difficult, but my back was KILLING me by the end of the process. At 6’2”, I pretty much have to bend down for everything. For the tall guys out there, build your table a little higher than a normal table.
Finishing up the peel
ply. I had not shaven yet…..
Finding the inserts was easy.
Step 3: Jigging and bonding the canard sections together
I used fishing line to make sure that the K jigs are lined up properly with one another. I went very slowly here. It was several nights of measuring and re-measuring before I finally decided that I was ready to bond the sections together. I bonded the outboard sections crooked. No problem. I cut right on the micro line with a hacksaw blade and re-micro’d them correctly. Try that with a metal airplane !!!
Hint: Don’t make the micro too runny. It will sag and leave low spots. Not too big a deal, but a pain in the ….
I used everything I could lay
my hands on to weigh it down for cure.
Laying up the bottom spar cap takes quite a bit of preparation, but the layup itself (other than taking a few hours) is pretty easy. It is sort of fun also, pulling the cross threads.
During this step, you also cut all the cloth for the bottom skin. I did not have the time to lay up the bottom skin, so I called it a day.
Step 5: Applying the bottom skin
I did this step a little bit out of order. I could not see the sense in laying up the skin and then digging part of the foam out with a drill while trying to not damage the bottom skin that you just laid up.
So, prior to laying up the bottom skin, I measured and measured again to get all the positions for the elevator hinge hardpoints. I cut the pieces out of the cores; traced them against the H100 foam and then micro’d them in place. I sanded the inserted pieces of foam down to shape and was ready to go. I HIGHLY recommend this to other builders. Very easy.
I decided to put the antennas on the bottom skin. The first attempt was success challenged (my way of saying I messed it up). Kent came over to help me with the bottom skin. He helped me take the unsuccessful antennas out and installing new ones.
Foam pieces cut from the cores.
H100 hardpoints ready to be
micro’d in.
Bottom skin in peel ply.
Step 6: Installing hard foam blocks for elevator hinges, the upper spar cap, and the upper skin.
I used PVC pipe on the fishtail and then used pine board to create the jigs needed for the top skin layup. Since I will be using bondo and didn’t want to sand it off my beautiful canard, I decided to leave the peel ply on the bottom skin for the bondo to be applied to. This turned out to be a very good idea.
For some reason, I do not enjoy the cloth cutting portion of the job. I worked on Chapter 13 at the same time, so progress on Chapter 10 was slow.
I laid the upper spar cap and the upper skin up in two different sessions; each lasted around 3-4 hrs.
Jigs bondo’d to the peel ply
of the bottom skin.
Top spar cap complete. I used double-sided tape to hold the
newspaper in place.
Sanding the top spar cap in
preparation for the top skin layup.
Top skin in peel ply, curing.