Step 1. Assembly of the fuselage sides

The first thing to do is to test-fit all the bulkheads made in chapter 4. I cut them a bit oversize, deliberately, so I had to trim the parts a bit to get a good fit. Using the multitool this is a quick job.

Test-fitting the front seatback. I have some gaps near the longerons, but these will be filled with flox so this is not a problem. The main issue is to have a good fit along the sides, since this is essential to the width of the tub.
Test-fitting the front seatback. I have some gaps near the longerons, but these will be filled with flox so this is not a problem. The main issue is to have a good fit along the sides, since this is essential to the width of the tub

Longerons

I used a contour gauge to transfer the shape from the fuselage sides to the corresponding bulkheads
I used a contour gauge to transfer the shape from the fuselage sides to the corresponding bulkheads

ch6_03
When fiddling with F22 I discovered a strange thing. I have built the bulkheads using the large drawings – not the M-drawings. I then discovered that the width of F22 on the large drawings is 33.7″ while the width according to the M-drawing should be 34.5″ approx!! There is no doubt that the drawings differ, but which one is correct? I asked the question on the Cozy-list, the canard-list and the canard-forum. No one could answer this but several builders had used the large drawings and confirmed that their F22 was 33.7″ wide. I got a tip to check the lift-tab-position of the canard to assure that they fit F22. That should be no problem, so I will continue with the 33.7″-version of F22.

As you can see - it's 11mm that differs on each side
As you can see – it’s 11mm that differs on each side

ch6_05
The tub is starting to take shape! Here I have followed the plan assembling the tub the right way up. Many builders have assembled the tub upside down, but I chose to do it the plans way. I started by leveling of the plank at the bottom, and also the 2″x4″ fore and aft. The longerons are at WL23 – i.e. 23″ up from the plank. This is only a dry-fit. I will use flox when I assemble the tub permanently. I measured the diagonals to look for straightnes. It was only 2mm difference, so I call it good to go. Just to the right of the tub in the picture is the landing-gear bow. I bought it from a builder in US that had to abandonded his project. It is brand new and came with the nose-leg as well. I got a good deal and helped him out as well. Pity he wasn’t able to continue his project though.

ch6_06
Before I floxed the instrument-panel to the fuselage-side I routed a groove in the foam with the Dremel. This will give a little better bonding since the flox will fill this groove.

ch6_07
After once again checking for straightnes in all dimensions, I have now floxed the front seatback, the instrument-panel and F22 to the fuselage-sides.

I used the plans method to squeeze the fuselage-side together using a couple of planks and some rope. Making a tourniquet it’s easy to adjust the pressure. Now it shall cure for 24 hours without anyone touching it. As Nat says in the plans: “Don’t even let the dog inside while curing!”.

While curing I started to cut all the BID-tapes using the plans method of laying an 8″ BID-ply ontop of some plastic, apply epoxy and then cut in 4 2″ strips. Worked rather good, but if I should do this again, I would use 3″ wide tapes rather than 2″. My problem was that the BID-tapes stretched a bit hence got more narrow. Then I had to widen them again, much hazzle her. Had I been using 3″ tapes instead I would have had a greater tolerence here. It was also a suprisingly long job to glue the BID-tapes on! I spent 2.5 hour to make the tapes and glue them on and peel ply.

The next step was to flox the landing-gear-bulkheads. Goofed up the aft. I forgot that there are a front and an aft side of this bulkhead. The front side had 8 plies of bid extra. I managed to flox it backwards. It was easy to cut it out and reattach it, no big deal at all. I discovered that I was not the only one doing this, luckily I discovered it early. I sent a tip off to the Cozy-FAQ mentioning that it’s easy to do a mistake here. After cure I floxed the front lower LG using the plans method.

Suddenly the temperature outside dropped to -10 degrees celsius (14F). Christmas is also just around the corner. I decided to turn the heater off to save some money and wait for the temperature to rise over christmas again. The weather-forecast says it will be cold until next year, so I guess this will be the last work done in 2009.

2010:

Off to work again! The temperature has raised to approx 0 degrees celsius so I have started the heat-pump again. I finished the landing-gear bulkheads using the plans method. I have also added 3 plies UNI on the front side of the front LG as per plans. Finally I BID-taped the front LG to the fuselage and taped the joint between the lower and upper front LG. The next step will be to turn the fuselage upside down!

Finally I BID-taped the front LG and the joint between the upper and lower LG and peel-plied the whole thing
Finally I BID-taped the front LG and the joint between the upper and lower LG and peel-plied the whole thing

ch6_09Since the temperature is low outside, it is rather cold at the floor. To boost the temperature while the epoxy is curing, I made a “heat-tent” of some plastic that I covered the tub with. Inside I have a small heater that raises the temperature to approx 30 degrees Celcius.

ch6_14
I’ve now turned the fuselage upside-down and floxed the lower part of the permanent firewall as well as taped the rest of the landing-gear

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