Chapter 13 - Section 5

Nose Floor and Sides

 

  Reinforcing the Glass Strut   Fabricating NG-30   Installing Worm Drive Assembly   Box Assembly 

 

 Nose Floor & Sides   Rudder Pedals   Master Brake Cylinders   Completing Nose Gear 

 

 Pitot & Static System   Closing the Top   Nose Door  

 

 

Making the Template for Nose Floor

I made a full size paper template per Fig. 21 such that I can transfer the dimensions (& curvatures) onto the 2" foam. I cut out the slanted ends with my table saw and the curved edge with my band saw.

 

[Hindsight: Take time to make a durable template because you will be using it many times down the road]

 

Dishing Out The Nose Floor

I was a bit confused from the plan instructions for this task. I wanted the nose floors to be uniform on both sides, but I also know if I do not have a reasonable guide, I won't have a prayer. After some thought, I drew out the contour (Fig.22) onto the nose floor template above. Then I transferred the contour onto the top of the foam using my tracing tool technique. With the Dremel and grinding disc, I set its depth (Per Fig. 22) and terraced the nose floor foam (along the contours) on both halves. The picture (left) shows the template / contour and the terraced foam halves.

 

 

 

 

 

 

Using a shortened straight edge sanding stick, I connected up the terraced steps. You'll know the sanding is close to complete when the terrace steps starts to disappear.  Finally, I used a high grit sand paper and touched up the overall contour. It's uniform and smooth.

 

 

 

 

 

 

 

 

 

Once I fit the halves between F-0 and F-22, I  microed the joggle in the floor behind F-22. I did not use foam as a filler (per plan direction) because I know I can get a much better transition with micro than foam.  Once done, I glassed the nose floor per plan with an additional BID over F-22 for better surface protection. I left 1.5" of bare foam along the edge (un-glassed). I peel-plied the entire surface.

 

 

 

 

 

 

 

 

Nose Cone Bulkheads

I made the nose cone bulkhead (NG31) per plan. However, I plan to put my landing light in the nose like most other builders. Until I figure out exactly what to do, the bulkheads are sitting on the shelf.

 

Nose Sides

I cut out the foam pieces (A, B & C) for the sides per plan. Again, it calls for carving of the foam on the inside walls of the sides. In order to make both sides symmetrical, I needed to establish a guide for the dishing effort. So, I laid down the template (above) flat on the table and drew out the side view of the foam (i.e. 2" x 24" rectangular box), enclosing the outermost contour line. Then I measured the vertical distance between the edge of the foam to the contour line at every 1" interval.

 

Then I drew a center line on top of the foam, joining the mid points of its edges (i.e. the 16.5" and 7.2" edge respectively). Using my Dremel and a grinding stone attachment, I removed the foam along the centerline, every 1" interval, to the depth (or vertical distance) established earlier. Again, using the terraced trench as a guide, I flared (dished) out the excess foam from both sides. Then I glassed the inside surfaces of the nose sides per plan. While working in the summer heat (my shop temperature is at 100 degrees F today), I forgot to take any pictures on the trenching effort.

 

[Hindsight: I didn't care for adding the micro fillet between the foam edges after the glass is at semi-cure state (per plan). I have to peel the glass back which tends to stretch the glass. In addition, its messy - the micro gets all over the place and it tends to run - resulting in a less than perfect fillet. If I do it again, I would rather wait till the glass cures, then trim, make a flox fillet (glass to glass) and then glass the nose sides on with BID tapes. I think I'll end up with a much better joint - but that's not per plan!]

 

Landing Light

There are many approaches on landing lights among Cozy builders - most of them chose to put them in the nose, myself included. I sought advice from senior Cozy builders and tried different automotive lights such as spot lights, fog lights, high beam, low beam etc. Due to the limited space we have at the nose, an appropriate light source (i.e. small, high intensity, not too much heat and inexpensive) is hard to find. I really liked Wayne Hicks' hinge approach. While looking for his recommended Camero Hi-beam lights, I spotted a Blazer driving light kit at AutoZone. Its relatively small, has a 55W halogen light bulb (changeable to 100W), has a driving light lens cover (which gives a 10 degree vertical and 20 degree horizontal light dispersion), an on/off switch, a fuse, a swivel mount (which allows me to point the light up/down & left/right) and costs $20 for two. It 'claims' it can pick up reflective signs at 2,600 feet away... well, we'll see.

 

I took it home and hooked it up to my garden tractor battery and compare it, side by side, to an automobile hand held spot light. Its more dispersed sideways (compared to a spot light) but it can easily light up details of a tree (e.g. leaves) 250 - 300 feet away with the 55W bulb. I can get a 100W bulb for around $7 that I have yet to try. As for the 2,600 feet reflectivity claim, that's got to be one giant reflective sign !!!

 

With the built-in swivel adjustments that come with the light, I decided to make a slotted L bracket and a couple of nut plates and hang the light off F-0. That way, I can position the light forward/backward and up/down, as well as point up/down and swing left/right. I made the bracket out of a 2" angle aluminum (as shown). I floxed the 2 nut plates on the back side of F-0 to support the mounting bolts. The swivel may be a bit weak, but I can always beef it up if needed.

 

Since the landing light took center stage at the nose, I have to move the NG-31 support (NG-32) from to the sides. Took a bit of work to find the correct curvature to the nose cone, but it is needed if I want to use the top half as a ballast compartment.   

 

 

 

 

Forming the Landing Light Window

I bought my nose cone from Featherlight, so I have to make a transparent window that conforms to the curvature of the nose for the landing light. I found great suggestions / methods from Cozy web sites on this subject. In addition, Wayne Hicks gave me a nice tutorial during his recent visit, so I was ready to try anything . I tried 1/8" thick Acrylic and polycarbonate (Lexan) with mixed results. Lexan is a trade name for polycarbonate which is harder and supposedly, has better scratch resistance qualities. You can get both of these materials from McMaster-Carr. Here's what I did:

 

First I hung and positioned the landing light on F-0 pointing straight ahead. Then I clamped the nose cone in place. With the light on, I traced out the light pattern on the nose cone with a pencil (this helped me to determine the size and location of the hole to cut). After removing nose cone from the fuselage, I transferred the pattern onto a piece of paper. Then I laid the paper flat on the the Acrylic and Lexan sheets respectively and transferred the pattern onto them using my spiked roller method. I cut and smoothed out the edges of the Acrylic/Lexan patterns. I also went to a local fabric store and bought a couple pieces of felt (1'x1' @ $.20 each) and cut them to size. I took everything home for the big task!

 

 

 

 

 

I rested the nose cone on a bean bag (as shown) to keep the nose cone from rolling around. Then I heated the oven to 275oF. I placed the Acrylic sheet on the felt sheet, on top of a cookie sheet and in the oven. I waited for about 3 minutes and was amazed how flexible the Acrylic sheet turned out - its like a sheet of cooked pasta!!! I picked up the Acrylic by the corner of the felt (the felt is not hot and I can manipulate it with my bare hands) and placed it inside the nose cone. With my kitchen mitts on, I carefully pressed down on the Acrylic such that it would conform to the shape of nose. I applied a bit more pressure at the top corners to keep then in place. Then I allowed it to cool. I did not experience the corners curling up per Wayne Hick's web - a lucky break for me.

 

 

 

 

 

I repeated the same process with the Lexan (polycarbonate) materials but did not achieve the same result. The Lexan material did not get as soft as the Acrylic at 275oF. I increased the temperature to 300oF for 6 minutes. It got a bit softer, but not soft enough to conform to shape readily. I had to press really hard on it, and ended up leaving smudges on its surfaces. In addition, the ones that were shaped had contour lines at the curved areas. Frustrated, I cranked up the oven temperature to 325oF. The Lexan started out-gassing with hundreds of bubbles forming inside, making it unusable .  I ended up with 4 Lexan and 1 Acrylic windows. All in all, Lexan did not work as well as I had hoped, I felt the Acrylic pane is the ONE!

 

 

 

 

Attaching the Window

As far as I can tell, all the Cozy builders floxed their windows directly onto the nose cone. Subsequently, the nose cone becomes part of the fuselage. It always bothered me as to what happens if the Acrylic gets scratched or turns yellow in time. It will require a bit of surgery to replace that window pane. The opportunity came after I cut the opening out of the nose. I trial fit the 'windows panes' and to my disappointment, they did not fit perfectly. The outer edges (of the window panes) prop itself up, preventing a nice fit. I pondered the problem a bit and decided to take an alternative mounting approach - I'll make the window pane removable...

 

I pressed the 'window panes' against the nose opening. Using a fine marker, I traced the opening outline onto the face of all the window panes I made earlier. I re-cut all the 'window panes' per its newly marked outline. Now, all the window panes wedge snuggly against the opening of the nose cone.

 

As it turns out, my last Lexan window pane conforms to the nose curvature the best. I put 1 1/2" packing tape along the edges of the 'pane' both front and back. Then I added 2 layers of duct tape along the inside edges as well. I re-fit the 'taped pane' onto the opening of the nose cone (as shown).

 

 

 

 

 

 

 

I applied flox all along the inside edges of the pane (Note: the Lexan is thicker than the fiberglass wall of the nose cone). Then I made a 4 layer BID window frame and glassed it onto the back side of the pane and nose. I peel plied and let cure. Note that the light brown wood frame (that the nose cone is taped to) has the same outline dimension as F-0. Its function is to keep the nose cone in the appropriate shape throughout this glassing process.

 

 

 

 

 

 

After the BID window frame cured, I removed the peel ply and 'popped' the window pane back out. Remember, the packing and duct tape I used earlier? Notice the 'step' frame on the nose that conforms perfectly to the pane. 

 

I marked off a 5/16" edge all along the window and trimmed off the excess with my FEIN tool. The 5/16" width window frame is to accommodate the nut plate on the back and diameter of the countersink on the front.

 

 

 

 

          

With the pane back in place, I match drilled 6 holes through the pane and window frame. The holes are for a 6-32 stainless steel machine screw and nut plate. I mounted the nut plates onto the back side of the window frame with flox and peel plied. Do not forget to grease the screws and countersink the face of the pane. 

 

 

 

 

 

 

 

After cure, I removed the peel ply, the 6-32 screws, and cleaned out the nut plates. If you look close, you can see the nut plate silhouettes through the BID window frame. Re-mount them all back in place - now I have a flushed landing light window and a removable window pane

 

As a side note, the 2 layer duct tape is to provide clearance for sealing compound (such as silicon RTV or the like) to seal off the edges. It will be applied prior to final mounting of the window pane.  

 

 

 

This is how it looks when everything is mounted onto the fuselage. The sealant (not applied at this time) should hide the nut plates, but you will see the stainless flat head screws.  

 

 

 

      

 

 

 

 

 

Nose Cone Door

A small door cover came with the Feather Lite nose cone - which is nice. However, I need to open it up for access, since I intend to use the nose cone compartment for ballast as well as access to the landing light. I followed the plans method for the nose cover (Section 11 of this Chapter) - a lip at the front end and a couple of stainless screws and nut plates at the forward edge of the cover.

 

Things on Hold

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Apply sealant between 'window pane' and support frame prior to final assembly for tight seal.