• If You Are Having Trouble Logging In with Your Old Username and Password, Please use this Forgot Your Password link to get re-established.
  • Hey! Be sure to login or register!

New kid on the block - Smith Cub

Most every one of the projects I have undertaken in my 50 years of initially building, then design- build projects, I have always looked at them for the education gained. I now call every project a collage course.
 
Dan, Before you close in between the interior panels and the fabric, you ought to look into some soundproofing insulation. A Cub is loud, particularly when there is an exhaust outlet just ahead and below the firewall. I can't help you with what. My Cub is naked, no interior and loud.
 
Dan, Before you close in between the interior panels and the fabric, you ought to look into some soundproofing insulation. A Cub is loud, particularly when there is an exhaust outlet just ahead and below the firewall. I can't help you with what. My Cub is naked, no interior and loud.

Thanks for this good suggestion! What thickness should be use in order to cut down the noise? I've checked Aircraft Spruce website and they have Super Sound Proof with Adhesive up to 3/4'' thick. I will investigate the matter...
Dan

 
Just throwing in my 2 cents. Our cubs have so much window area that I suspect insulation doesn't help as much as it would perhaps on other types of aircraft. I'd love to fly the same make/model experimental Super Cub with and without insulation to see if there is indeed a noticeable difference (that justifies the additional weight). Maybe so.
 
In my case I'm certain that the objectionable noise is engine produced from the dual exhausts below. The wind noise is something else.
 
Just throwing in my 2 cents. Our cubs have so much window area that I suspect insulation doesn't help as much as it would perhaps on other types of aircraft. I'd love to fly the same make/model experimental Super Cub with and without insulation to see if there is indeed a noticeable difference (that justifies the additional weight). Maybe so.

Ted, are you saying that you are using insulation as sound proofing? That would solve two problems with one single action...
 
Cabin - Wing Root Fairings

I made the Wing Root fairings in two parts. The first one is the main panel covering the upper cabin section then the second part covers the leadind edge portion inside the cabin.

135.JPG 136.JPG
All parts ready to be installed

142.JPG
If you look closely at this photo, you'll notice that the tube is proud of the channel thus I had to bend a little bit the panel.

139.JPG
I'm not using metal screws. All parts are attached using machine screws & anchor nuts.

152.jpg
I think I'm done with aluminum on the fuselage...To be honest i'm not sure...

Dan
 

Attachments

  • 135.JPG
    135.JPG
    130.1 KB · Views: 151
  • 136.JPG
    136.JPG
    116.9 KB · Views: 146
  • 142.JPG
    142.JPG
    148.8 KB · Views: 164
  • 139.JPG
    139.JPG
    130.8 KB · Views: 171
  • 152.jpg
    152.jpg
    116.2 KB · Views: 194
More about Floorboards...

I had few questions about how the floorboards were attached to the fuselage. Easier to explain it with photos.

084a (5).jpg
I used spade bits to fit exactly the countersunk washers - Screw size #8

084a (6).jpg 084a (7).jpg
With a countersunk washers you make sure that nothing should get caught when tossing luggages around...

084a (8).jpg 084a (10).jpg 084a (11).jpg
Concerning the middle part, I made the holes right in the middle of the floorboards.

084a (12).jpg 089.JPG
There you go!
Hope this answer your questions!
More to follow!
Dan
 

Attachments

  • 084a (5).jpg
    084a (5).jpg
    57.3 KB · Views: 155
  • 084a (6).jpg
    084a (6).jpg
    62.9 KB · Views: 159
  • 084a (7).jpg
    084a (7).jpg
    57.4 KB · Views: 169
  • 084a (8).jpg
    084a (8).jpg
    74.5 KB · Views: 156
  • 084a (10).jpg
    084a (10).jpg
    73.8 KB · Views: 172
  • 084a (11).jpg
    084a (11).jpg
    61.9 KB · Views: 151
  • 084a (12).jpg
    084a (12).jpg
    48 KB · Views: 155
  • 089.JPG
    089.JPG
    144.5 KB · Views: 157
Last edited:
Overhead Trim

I bought the Overhead Trim Kit from Javron. Nice parts as always.

060 (5).jpg
I needed to weld tabs in order to give some support to the cover as well as for the trim assy.

060 (9).jpg 060 (12).jpg
Better view of the installation.

062 (1).jpg
Now, for the cover...

062 (3).jpg
There are compound curves and bends for the cover.

062 (4).jpg
Using a steel rod gives you a nice curve

063 (1).jpg
I've made 4 covers to get one to fit correctly. The joy of making your own parts!

147.jpg
The chosen one.

150.JPG

061 (3).jpg 061 (2).jpg 061 (1).jpg
Views with the Overhead Trim installed.

More to follow!

Dan
 

Attachments

  • 060 (5).jpg
    060 (5).jpg
    78.7 KB · Views: 158
  • 060 (9).jpg
    060 (9).jpg
    61.9 KB · Views: 161
  • 060 (12).jpg
    060 (12).jpg
    69.1 KB · Views: 162
  • 062 (1).jpg
    062 (1).jpg
    71.4 KB · Views: 152
  • 062 (3).jpg
    062 (3).jpg
    83.2 KB · Views: 169
  • 062 (4).jpg
    062 (4).jpg
    72.1 KB · Views: 163
  • 063 (1).jpg
    063 (1).jpg
    61.4 KB · Views: 154
  • 147.jpg
    147.jpg
    56.8 KB · Views: 139
  • 150.JPG
    150.JPG
    135.2 KB · Views: 146
  • 061 (3).jpg
    061 (3).jpg
    59.5 KB · Views: 163
  • 061 (2).jpg
    061 (2).jpg
    50.6 KB · Views: 144
  • 061 (1).jpg
    061 (1).jpg
    74.2 KB · Views: 148
Firewall

I’ll be starting to work on the boot cowl and before I do this, I must position the firewall accurately. While checking the Northland CD about measurements and installation, I noticed that the flange for the firewall as well as the ridges supplied by Nick did not seem to be installed correctly

View attachment Firewall 12365.pdf
See the firewall drawing #12365 from CD

Someone (I just can’t remember his name…really sorry) on one of the posts explained the following concerning the installation of the firewall:
‘’Firewall ridges (or bumps) should ideally face forward to the engine (engine side) and the back side should rest flat on the steel tubing going across the airframe.

Now the flange that goes around the firewall…The top part will wrap around the outside of the firewall (facing engine) and as you go down on both sides there is a notch at the bottom where the flange now goes inside the firewall. The purpose of this is that when any fluid (water / oil) splashes onto the firewall, the fluid will run down the firewall and as it gets down to the bottom the fluid just going to drip off but if you have a ledge / flange there, there is a risk that the fluid can drip inside and get back into the airplane…’’

078.jpg 076.jpg
So, here is the firewall from Nick and see what I mean. Either facing forward or back side, there is something wrong. I explained the problem to Nick and right away a new piece of metal was coming my way. Nice to deal with the Smith!

099.JPG
So, I downloaded, printed & glued together the 16 pages in order to get a full size drawing for accurate measurements

101.JPG
Made a plywood template for the exact radius

110.JPG
...And notched it.

114a.jpg
All drilled and ready to install the flanges.

120a.jpg
Done.

123.jpg
Centered on the fuselage!

More to follow
Dan
 

Attachments

  • Firewall 12365.pdf
    195.6 KB · Views: 458
  • 078.jpg
    078.jpg
    51.6 KB · Views: 169
  • 076.jpg
    076.jpg
    57.4 KB · Views: 169
  • 099.JPG
    099.JPG
    140.6 KB · Views: 171
  • 101.JPG
    101.JPG
    192.1 KB · Views: 171
  • 110.JPG
    110.JPG
    117.5 KB · Views: 155
  • 114a.jpg
    114a.jpg
    108 KB · Views: 158
  • 120a.jpg
    120a.jpg
    52.6 KB · Views: 158
  • 123.jpg
    123.jpg
    109.1 KB · Views: 175
Very nice project! I see many place I would have not fabricate and install some weight, but I assume your goal is not to have a lightweight plane. More a fully loaded and very well equipped exp SuperCub.

Keep up the good work!


Thanks for sharing
 
So, I downloaded, printed & glued together the 16 pages in order to get a full size drawing for accurate measurements.

Dan
It is not a good practice to scale dimensions directly from a drawing. In this case it may work, but there is no guarantee of accuracy.
 
Very nice project! I see many place I would have not fabricate and install some weight, but I assume your goal is not to have a lightweight plane. More a fully loaded and very well equipped exp SuperCub.

Keep up the good work!


Thanks for sharing

Thanks Oli,
You're right! As I mentionned earlier, it is going to be more of a Gentleman's Bush Plane were you can do a little of bit of everything in a comfy environment.
 
It is not a good practice to scale dimensions directly from a drawing. In this case it may work, but there is no guarantee of accuracy.

Good point. I got caught couple times with this!! So, I made sure that all measurements were 100% scale before anything else.
 
Boot Cowl Assembly - Part 1

Now that the firewall is fitted, it is time to work on the boot cowl. The boot cowl that came with the kit was made of 2 long pieces (5051-H32 .032'')

125 (22).JPG
Here is one of them.

040.jpg
These 2 pieces overlap at the top & bottom

125 (16).jpg
So I fitted both pieces and drilled holes equally spaced

125 (23).JPG
Next,cut the angles - Fuselage cowl reinforcement according to drawing

125 (24).JPG
...and bend them 90 Degrees

126 (2).JPG
Time to install these babies...

Now, before I went too far, I stood back and observed the overlap of the aluminum sheets on top, I just did not like the look of it… I decided right there and then that it should be a one piece on top and a piece on each side joining mid-section thus making an easier access to the pedals section in case of problems.

126 (16).JPG
Drawing mid-section cut line.

126 (17)a.jpg
and cutting it.

126 (18).jpg
The upper section will now be used as a template.

126 (24).JPG
New top piece

128 (8).JPG
One more photo for the Feds while installing the cowl reinforcements

128 (10)b.jpg
Reinforcements being installed on top section.

Part 2 to follow soon!
Dan
 

Attachments

  • 125 (22).JPG
    125 (22).JPG
    150.4 KB · Views: 167
  • 040.jpg
    040.jpg
    59.5 KB · Views: 157
  • 125 (16).jpg
    125 (16).jpg
    131 KB · Views: 154
  • 125 (23).JPG
    125 (23).JPG
    118.5 KB · Views: 153
  • 125 (24).JPG
    125 (24).JPG
    158.2 KB · Views: 146
  • 126 (2).JPG
    126 (2).JPG
    145.2 KB · Views: 148
  • 126 (16).JPG
    126 (16).JPG
    128.6 KB · Views: 143
  • 126 (17)a.jpg
    126 (17)a.jpg
    71.5 KB · Views: 148
  • 126 (18).jpg
    126 (18).jpg
    128.8 KB · Views: 158
  • 126 (24).JPG
    126 (24).JPG
    145.5 KB · Views: 144
  • 128 (8).JPG
    128 (8).JPG
    113.1 KB · Views: 151
  • 128 (10)b.jpg
    128 (10)b.jpg
    195.3 KB · Views: 157
One issue that can occur when building the boot cowl without weight on the nose is the frame can flex/move once you add the engine/prop up front. I rebuilt my boot cowl into a three piece when I was replacing a cam and had some time waiting for parts. Everything fit fine until I hung the motor and then the lower gingerbread holes did not quite line up. Before you paint hang a motor or mount on the mount and make sure everything lines up. You are moving along at a great pace so another bit of advice when you go to do the panel. Have the top boot cowl section on when you do the panel and install every part sitting in the pilot seat. Make sure you use gage nuts and have a large easy removable middle section to stick you arm in to the back of the panel, this you save you a lot of heartache when you have a simple gauge issue in the future. Great build!
DENNY
 
... and have a large easy removable middle section to stick you arm in to the back of the panel, this you save you a lot of heartache when you have a simple gauge issue in the future.
A buddy who has a large-ish Dynon display in the middle of his panel uses that as his "access hole" for everything else. He just pops out the Dynon (which he installed with sufficient length of wires, etc. so it will sit on top of the panel after removal) and uses that great big hole to access everything else. I thought that was pretty slick, and will incorporate that idea when I install an EFIS in my Rans S-6.
 
[QUOBefore you paint hang a motor or mount on the mount and make sure everything lines up. You are moving along at a great pace so another bit of advice when you go to do the panel. Have the top boot cowl section on when you do the panel and install every part sitting in the pilot seat. Make sure you use gage nuts and have a large easy removable middle section to stick you arm in to the back of the panel, this you save you a lot of heartache when you have a simple gauge issue in the future. Great build!
DENNY[/QUOTE]

Denny, Thanks for this good advice. I'll sure check that out when install the engine!! Thanks again. Dan
 
A buddy who has a large-ish Dynon display in the middle of his panel uses that as his "access hole" for everything else. He just pops out the Dynon (which he installed with sufficient length of wires, etc. so it will sit on top of the panel after removal) and uses that great big hole to access everything else. I thought that was pretty slick, and will incorporate that idea when I install an EFIS in my Rans S-6.

Jim, thanks for pointing that out. I actually did a bit of planning for the instrument panel and as you can see I will have an IPAD in the middle of the panel with an IPhone that will be easily removable to access the back of the instrument panel. It is not the final version but at least I have something to think about for the time being...Dan

Instrument Panel Template.jpg
 

Attachments

  • Instrument Panel Template.jpg
    Instrument Panel Template.jpg
    148.7 KB · Views: 179
Boot Cowl Assembly - Part 2

128 (3)A.jpg
Now that the top piece is lined up, I'll make the part surrounding the ''V'' tubes

128 (2)A.jpg
Template and its brother aluminum

128 (4)A.jpg 128 (12)A.jpg
Rounded the front part and riveted it.

125 (9).JPG
In order to center the holes on the channels where the boot cowl will attach
I made a little guide by using an anchor nut.

125 (13).JPG 125 (12).JPG
So many holes to drilled, this guide really help speeding up the work.

140 (9).jpg 140 (11).jpg
Before & after

129 (1).jpg
Lining up top and bottom parts

129 (4).JPG
Installing anchor nut on the bottom parts

140 (2).jpg
Added the side trims to the boot cowl.

More to follow...
Dan
 

Attachments

  • 128 (3)A.jpg
    128 (3)A.jpg
    137.6 KB · Views: 276
  • 128 (2)A.jpg
    128 (2)A.jpg
    123.1 KB · Views: 288
  • 128 (4)A.jpg
    128 (4)A.jpg
    137.4 KB · Views: 285
  • 128 (12)A.jpg
    128 (12)A.jpg
    134.7 KB · Views: 267
  • 125 (9).JPG
    125 (9).JPG
    114.6 KB · Views: 142
  • 125 (13).JPG
    125 (13).JPG
    117 KB · Views: 150
  • 125 (12).JPG
    125 (12).JPG
    115.2 KB · Views: 159
  • 140 (9).jpg
    140 (9).jpg
    162.7 KB · Views: 155
  • 140 (11).jpg
    140 (11).jpg
    150.9 KB · Views: 154
  • 129 (1).jpg
    129 (1).jpg
    124.1 KB · Views: 153
  • 129 (4).JPG
    129 (4).JPG
    126.3 KB · Views: 139
  • 140 (2).jpg
    140 (2).jpg
    125 KB · Views: 147
I am kind of surprised you are not forming a lip on the panel edges where the filler panels are up close and may contact the tubes as things flex about?
 
Take your front interior side panels out, put you dash in place and then try to get the front side panels back in. Most of the ones I have seen are a major pain to remove with the dash in place. Yours look kind of tall and I suspect will be very difficult to remove without taking the dash off. Something to fix now. Your work is excellent for fit and finish however making everything tight can have drawbacks when it comes to working on the plane down the road. The fuselage is going to change as you fly it leave some space for it to grow and adjust over time.
DENNY
 
Denny, I did exactly that when I made the interior side panels. I trimmed them as much as possible for play and to be honest with you, it is still a pain to remove them but feasible without removing the dash. I would not like to remove them too often!! Thanks for the advice!
 
Not too sure what you mean Charlie?
I would need to look for an image.

What I do where the edge of the aluminum or other sheet could get against a tube, I cut the sheet proud and then hammer form the edge back such that it would have a 5 to 8mm surface, call it a flange against the tube rather than the thin edge of the sheet which will in short order damage the paint/ powder coat and soon wear into the steel itself.
This provides a much larger bearing area that can be cushioned to reduce the chance of wear on ether part.
 
This is aluminum against aluminum. A baffle inside a dry sump oil tank I build a few decades back. The edges of the internal baffle in this case are simply folded such that no edge will bear on the surface of the tank skin.
It is the fold formed be it simple or complex that spreads the load against it's mating surface that lets the parts live allot longer as vibration or other stresses work the parts.
P5270037.JPG
 

Attachments

  • P5270037.JPG
    P5270037.JPG
    150.2 KB · Views: 197
I spent a bunch of time looking through my image folders of the past 20+ years of both customer as well as my own protects, it appears I have not taken pictures of formed edges of my sheetmetal work. Plenty of formed weldments but nothing showing edge work of panels.
A few decades back a partner in one of my aircraft builds introduced me to "helicopter tape" this being a clear tape that is used on the leading edges of blades.
I have put this on tubing where the aluminum will be touching, be it an edge or laying flat against it.

Between the tape and making sure no direct edges are in reach of the tube I have not even had to touch up paint in contact areas.

I have more recently bought some double sided very high bond tape for where a panel will lay against structure. This has it's value to quite things down.

Your work looks sweet, it is very clear you have a long history working with sheetmetal.
 
Back
Top