The metal scoops on top of the Cub engine are referred to as Eyebrows.
For years I had made them from thin plastic. they would hold up for a year or two. So I decide to grab the full scale drawings and scale them down. Next cut and form then from then metal. The source of meatal I’m using is a metal yard sale sign that can be found at most hardware stores.
- One metal Yard sale sign or a sheet of .012 metal.
- Drill bit close to .035 .
- #0 x 1/4 – Button Head Sheet Metal Screws – Hex Drive from Micro Fastener.
- #0 x 1/2 – Pan Head Sheet Metal Screws – Phillips from Micro Fastener.
- Mat Black Spray Paint.
- JB Weld.
- Some scrap hard balsa or spruce.
What you will see below in this construction is the 1/4 scale version.
Tip if using a metal sign, it is recommend to put the sign side to the inside and the non printed side to the outside. After painting you can see where the sign was printed. If you look below you can see how the print is raised a little. The black arrow is pointing to some of the sign text after painted black.
So lay the template out and trace around it. Make note of the bend lines and do not cut them. For the back rounded section take note from the photo of how its nipped. Also for the bottom opening that will set on top of the valve covers, you will see I do not trim them to the line I do this later to get them to fit with the engine outline. Also don’t forget to mark the location for the rivets. Star to make your bends, including the rounded back side. I have a pair of covering pliers that help to make the long bends.
I love using the #0 x 1/4 – Button Head Sheet Metal Screws – Hex Drive as they look like small rivets. Make note the hex drive is easy to strip out, so I use the phillips #0 screw to make the threads in the meatal fist then switch it out with the hex heads. I use a .035 drill bit in a hand finger drill to make the holes. I start with my screws at the back bottom corner and work my way to the top of the back rounded part. As you get to the top you will need to stretch the inside ends to meet and I use a set of vise grips to hold it while I finish the rivets.
Now that you have it together with the phillips screws start replacing them with the hex head screws. When finished with putting the hex screws in, flip them over. on the back side where the screws are exposed and the metal is put together I coat it with JB weld. This will keep the screws from vibrating out and keep the meatal together.
After the JB Weld has set over night its time to trim the valve cover openings. I use a small fine sanding drum on my rotary tool for this job.
Now time to get the engine ready for the eyebrows. On the full scale they have a mounting bracket at the top center screw of the valve covers. I dig down in the back of the head with a bur tool in my rotary tool. I make a hole so i can insert 1/16 thick spruce sticks. they need to be left long enough for the mounting tabs. on the back side of the engine you will need to add some 1/4 square spruce or hard balsa to mount the eyebrows too. I paint all the areas a flay black to help hide it.
Again using the phillips screws first to make the holes then switching over to the hex drive screws. The mount tags are just some scrap metal (for 1/4 scale I made them 1/8 wide and 1/2 inch long) I rounded the edges a little to make it look like this ). I make the holes in the engine side and mount them to the engine. Then set the eyebrow in place and finish adding two more screws to the top into the eyebrow.
Now for the finish project.