       Working on Chpt 10 - Canard Construction updated: 27/05/2008
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Step 2 – Preparing the Strut for Installation The Featherlite strut was sanded dull using 36 grit sandpaper and took me about an hour to get all the surfaces sanded. I then placed the Strut upside down, using the slot in my build table cut in chapter 5 for the Instrument Panel, to stop it from falling over. From this point I followed the plans method for measuring the strut, except I used a vernier to find a couple inside centre reference points, to help with getting the measuring tape close to the middle cord of the strut. The tape when removed and placed flat onto the table measured 97.9". I repeated the whole exercise again using a new piece of tape, just to make sure I had not make any mistakes and again obtained a measurement of 97.9", which meant I needed to remove 0.95" from the end of each leg to get 95".
I marked off 0.95" on the Leading edge of each leg and using the protractor on my combination square, I marked the 8° cut line tapering in towards the Trailing edge. I did not bother making the 8° wooden guide block as suggested in the plans and just cut the ends off using a new 24TPI hacksaw blade. Once completed I checked the 8° end cuts again using the protractor and it looked OK.
The next step was to find the spot that was 5.75" wide and trim it down by 1/8". I used my vernier to measure the strut and mark the area to be removed. The 1/8" was easily removed using a file and all corners were rounded. I then placed the strut at the end of the table with the leg ends hanging over the side of the table. I supported the legs as shown in the photos with pieces of wood clamped to the table and placed 3 x 2" nails into 2" wooden blocks giving me a total clearance of 4" under the strut. I did it this way to give me more room to move around the strut when fibre glassing. I then rolled out the UND cloth and cut the 8 strips x 12" wide at 30°. Before laying up the 4 UND plies I marked the strut with a couple 35° reference pencil lines.
The 4 UND plies took almost 6 hrs to lay-up, even with the help of an extra per of hands and I found the whole process very tedious and fiddley, especially trying to get a reasonable finish underneath where the glass met on the LE. I'm not looking forward to turning it over and repeating the whole process again from the other side. The next day I removed the Peel Ply and cleaned up the LE, overall I was quite happy with the finish, except for a couple ridges which I had to sand flat where the glass had overlapped slightly in a couple places. The LE cleaned up nicely with a file and a little sanding. Once I was happy with the general appearance of the Strut, I then marked the position for the Brake Line Conduit made from 1/4" drinking straws, starting 8" in from the end of each leg and finishing 16" in from the centre on both sides, a total length of 24" per side. Whilst looking around for suitable straws I happened to find 2 different sized straws, by chance the smaller black straws were a nice sliding fit inside the larger red straws, so I decided to used a black straw inside each red straw across the joint, providing extra support and alignment. After cure the black straws would simply be pushed out.
Using 2½ straws per side gave me the required 24", the joints were taped together to ensure that micro would not get through and secured to the top edge of the strut using 5 minute epoxy. I folded normal kitchen aluminium foil until I obtained the required stiffness and taped this in place as a guide for the 2 ply BID tape. Before applying the 2" wide BID tape, I filled and contoured around the straws using micro and after glassing peel plied the outside of the lay-up. The Strut was again set up on the 2" nails and wooden blocks. The 2nd 4 UND plies were applied from the LE side of the strut, same as before except this time, I tried wetting out each ply on grease proof paper first and then laying up on the strut along the 35° reference lines. I found this method easier and the UND cloth kept its shape better, but the complete lay-up still took almost 6 hrs to complete. The complete strut was then peel plied and left to cure over night. After cure the strut was removed from the nails and the TE and brake line conduit were cleaned up before moving onto making the jig box.
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