• 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!

Building a Scratch Built Cub

Thinking about Airventure, can we get a tour of the shop? yes we know it is a busy week for you.
 
Hello John

Your work is awesome, really getting exited to see the possibilities.

Im thinking of starting a scratch build project my self, but dont really know how or where to start, I see you have some print out patterns, did those come out of some instructions ? or where can I find those templates ?
Also curious do you have a list of materials available as to buy all the tubing in bulk ?
Really hope you can help me out to get started.
Best regards

Chrsitian
Lunch Time Aviation presents a builder's update: It's lunch time, so I thought I'd take a little time to provide my project update. Continuing with the Torque Tube assemblies, I have attached photos of the torque tube bearing mounts. I typically draw any flat steel parts on paper, then glue (spray adhesive) the paper template to the sheet, than cut out the part. Here I used a portable hydraulic punch I borrowed from work. I got lucky that the large hole I needed to punch was the same diameter as one of the punch and die sets we had. Electricians use these punches to punch holes in electrical panels. After punching, and cutting the part out using a cut off wheel or a sheet metal shear if applicable, we bent up the flanges, and assembled. In order to cut out the curved lines to fit to the bearing tube, I drilled a series of small holes just outside the line, then wiggled the scrap part away from the good part, followed by using the bench top grinder to smooth out the steel to the shape of the curved line. We fixture up the parts welded. My project partner has been doing the welding while I typically fabricate many of the parts and the fixtures. It works out well for us. We're building two cubs, so our combined interests works out well for both of us.
attachment.php
attachment.php
attachment.php
attachment.php
attachment.php
 
Beautiful job, great workmanship. Please keep the updates coming, I always enjoy seeing a projects progress. Thanks for sharing.
 
“Also curious do you have a list of materials available as to buy all the tubing in bulk ?
Really hope you can help me out to get started.”

Hello Christian,
Thank you for the positive comments about my project. My friend Charlie and I are each scratch building two Super Cubs, and are sharing our skills for these projects. I really enjoy the scratch building process, however it does take considerable time, especially when we work on our projects infrequently.
We are primarily using the original Super Cub drawings by Piper. We are using the Northland cd of drawings, and we also often reference Christian Storms helpful website Supercubproject.com to look up drawings. I want to credit Christian Sturms site where he fabricated the control sticks and torque tube, which helped me so much when building our assemblies.
Regarding a list of tubing, I may still have a list, and I will look for it. We simply referenced the drawings, and created a list of tubing we needed, then ordered it. For a realativeyl small cost, a person can work for quit a while fabricating a fuselage and gear legs.
if I were to make another, I would buy tail surfaces at AirVenture in the AeroMart tent (used parts) instead of fabricating these as there is always a supply of good pieces, at reasonable prices.
Regarding my drawings I use for templates, I do have a file, however I lost the availability of AutoCAD software, so I’ve been lacking the capability to manage the files. I have been wanting to find a free source to use my files, and I have this on my list to do.
I am currently away from home for a few days, which will delay me in looking through my files.

I hope this helps,
john

 
John

Thank you for the reply, any help is great, I am far far away , ( in mexico ) so I am pretty much on my own except for this forum. so this is why we really want to make sure we get a correct list of parts going because any mistake can cost us a lot of time and expense to get missing or wrong parts down here.

Regards

Christian

“Also curious do you have a list of materials available as to buy all the tubing in bulk ?
Really hope you can help me out to get started.”

Hello Christian,
Thank you for the positive comments about my project. My friend Charlie and I are each scratch building two Super Cubs, and are sharing our skills for these projects. I really enjoy the scratch building process, however it does take considerable time, especially when we work on our projects infrequently.
We are primarily using the original Super Cub drawings by Piper. We are using the Northland cd of drawings, and we also often reference Christian Storms helpful website Supercubproject.com to look up drawings. I want to credit Christian Sturms site where he fabricated the control sticks and torque tube, which helped me so much when building our assemblies.
Regarding a list of tubing, I may still have a list, and I will look for it. We simply referenced the drawings, and created a list of tubing we needed, then ordered it. For a realativeyl small cost, a person can work for quit a while fabricating a fuselage and gear legs.
if I were to make another, I would buy tail surfaces at AirVenture in the AeroMart tent (used parts) instead of fabricating these as there is always a supply of good pieces, at reasonable prices.
Regarding my drawings I use for templates, I do have a file, however I lost the availability of AutoCAD software, so I’ve been lacking the capability to manage the files. I have been wanting to find a free source to use my files, and I have this on my list to do.
I am currently away from home for a few days, which will delay me in looking through my files.

I hope this helps,
john

 
John,
Working with a partner makes a lot of sense to me now. Another set of eyes and functional brain would have kept me from making some mistakes. You are absolutely right on the pile of raw materials thing. It will keep a guy busy for a long time cheaply if you enjoy the process. If you make an irreversible mistake, it goes in the trash a lot less painfully than wrecking a kit part. Your work is incredible by the way, keep the pictures coming.
Christian,
I started with the aluminum wings. Spars, drag wires, drag wire nipples, and hardware you will likely buy. Everything else is sheet stock and time. The hardest thing for me is the hardware, but that is my own fault. There is a pile of it. Rarely a local source for aircraft stuff. You pause a lot waiting for the right length bolts, rivets, washers, and nuts to come in the mail. If a guy changes nothing, wing hardware is a breeze, order it from a list created from members and available on this forum. Scratch building can be done, just not in a hurry.
Thanks,
Jim
 
Good work. How many hours did the first fuselage take vs the second one?

Hi, Regarding time to build a second fuselage, we did not track hours specifically, however the second build is significantly easier and quicker than the first. My joke is that the first airplane is experimental, while the second is professionally built as we learn so much along the way.
I tend to often do more thinking than building, and after a decision is made, and with a little experience, the second time around seems to go twice as fast.
I hope this helps, and I hope to post more progress reports soon.
john
 
Torque Tube Mast 40212

Does anyone have a drawing in the flat of part 40212. This is the mast for the torque tube. I was needing one to cut the mast from sheet metal.
:wink:
 
An Over Due Scratch Building Update

Work continues on my Super Cub project, slight as it has been.
A lot of various tasks completed.

IMG_5471.jpg
The D window frames have been welded in place. To date the window frames
have beensome of the only purchased parts.


3.jpg
The rudder and brake pedals have been fabricated, however the re-enforcing plate
for the heel brakes was needed.


1.jpg

I sheared and bent a piece of flat steel, then drilled holes using a step drill bit.

2.jpg
Using a dremel tool with a small cut off wheel, followed by filing the edges even
and smooth makes for a clean part. Notched the ends to fit as needed.

3.jpg

Here, the re-inforcing plate is clamped in place with the heel
brake pedals in place. Still need to drill holes to attach the brake pedals.IMG_4623.jpg

Fabricated the Rudder Stops. These can be threaded if needed to
insert a bolt for adjustments.IMG_2939.jpg

Added a tube across the gear legs as a step.IMG_5472.jpg

Fabricated and located the rearward fairlead brackets in place.
Note that the wire rope and twine is temporary and will be replaced with AN wire rope.


IMG_4214.jpg

Curved "Piper Channel" gets welded in place for the boot cowl to attach to.
The Piper Channel is made by shearing and bending sheet steel.
A lot of this stuff is needed.


1.jpg

To bend the radius on the Piper Channel into the correct shape, follow the blue prints.
I swung an arc using a tape measure hooked to a screw head, to draw the
correct radius onto plywood.

2.jpg

Simply bend the channel to match the arc drawn on the plywood,
then cut to final length.

IMG_4157.jpg

Used a framing square to line up the Piper Channel onto the fuselage.
Charlie then welded it in place for me.

4.jpg

Finally add a couple of braces and spacers to hold it in place so the
fabric does not distort it when shrunken in place.

IMG_5475.jpg


Thank you for looking. More to come on a more frequent basis.
John
 

Attachments

  • IMG_5471.jpg
    IMG_5471.jpg
    131.8 KB · Views: 211
  • 1.jpg
    1.jpg
    75.4 KB · Views: 197
  • 2.jpg
    2.jpg
    124.1 KB · Views: 204
  • 3.jpg
    3.jpg
    97 KB · Views: 239
  • IMG_4623.jpg
    IMG_4623.jpg
    76.9 KB · Views: 204
  • IMG_2939.jpg
    IMG_2939.jpg
    112.1 KB · Views: 211
  • IMG_5472.jpg
    IMG_5472.jpg
    78.2 KB · Views: 220
  • 1.jpg
    1.jpg
    61.6 KB · Views: 209
  • IMG_4214.jpg
    IMG_4214.jpg
    69.1 KB · Views: 205
  • 2.jpg
    2.jpg
    52.4 KB · Views: 188
  • IMG_4157.jpg
    IMG_4157.jpg
    62.8 KB · Views: 204
  • 4.jpg
    4.jpg
    78.8 KB · Views: 221
  • IMG_5475.jpg
    IMG_5475.jpg
    136.9 KB · Views: 218
Thanks for the updates, John!

Do you actually fabricate the Piper channel? I've bought it because it seemed too hard to produce efficiently.
 
Thanks for the updates, John!
Do you actually fabricate the Piper channel? I've bought it because it seemed too hard to produce efficiently.

Hi Vic,
Yes, the Piper Channel was made using 1" wide strips of 4130, 0.020" or 0.025" thick (can't remember which). these came in 6 foot lengths from Aircraft Spruce.
I placed a piece of masking tape on each end, and a piece at the center, marked a line 5/16" from each edge on the tapes, placed it in the break, bend, flip it around, bend, making sure to include generous radius' on the bends.
I suggest to folks to cut a small length of material and bend up some samples, prior to bending 6 foot pieces. It does take some time, and it is hard to make the channels all look exactly the same, if needed to be the same.

Thanks Vic, I like your building project and the boat you built,

john
 
Requesting thoughts on fabricating a home made wind shield for experimental Cubs?

Does anyone have practical experience in fabricating a windshield for a PA-18 from scratch?

The potential challenges I see are that the wind shield would not have a permanent set to it, making
it more difficult to fit and to install.

Are the purchased wind shields made so some cutting and fitting
is required to accommodate any variances in final assembly and cowl shape?


Windshield.PNG

IMG_5475.jpg

Thanks for any thoughts on this one,

john
 

Attachments

  • Windshield.PNG
    Windshield.PNG
    176 KB · Views: 210
  • IMG_5475.jpg
    IMG_5475.jpg
    136.9 KB · Views: 195
Are the purchased wind shields made so some cutting and fitting
is required to accommodate any variances in final assembly and cowl shape?
Seldom can a purchased windshield be dropped in without any cutting and fitting. Over the past 60 odd years of installing windshields in various airplanes, I can not think of even one which did not require cutting and fitting. Some more than others.
 
Yes, the windshields have extra material so they can be trimmed to fit. I don't think any, even the factory replacements, just drop in. It would be quite a challenge to make your own, and there is no need to do so. Buy one and trim to fit. Its all good.

Best of luck

Bill
 
Requesting thoughts on fabricating a home made wind shield for experimental Cubs?

Does anyone have practical experience in fabricating a windshield for a PA-18 from scratch?
Another thought. Though I have never attempted to form a windshield, I have heat formed smaller pieces of plexiglass. Due to the size, shape, cost of materiel and steep learning curve I suggest that the cost of buying one all made from someone who does it for a living is very short money. You only need to crack one or distort it directly in your line of vision to create an expense higher than buying just one good one.
 
About 2003 a friend and I took some molds for his biplane windshields to Airplane Plastics in Dayton,OH. It was only a two hour drive. The owner was kind enough to show us around his shop and it was an eye opener for us. We got to observe his crew making Van's canopies for side by sides that day. The process of the flat sheet coming out of the oven and carried to the male mold happened in seconds by workers that knew exactly what they were doing. After that huge piece of plex was where it needed to be they hooked up a vacuum hose and drew it down on the male mold perfectly. I have never seen so many vice grip #11's in my life. They use them on the outer ring to clamp the plex in place. All this takes place in seconds. I knew right then I was never going to be doing something like this even though I love to make airplane parts. I came home and planted rubber trees so I could make my own tires, it made more sense.
 
Last edited:
Lunch Time Aviation presents a Builders Update


Baggage Area

IMG_3058.jpg

Although I incorporated the "Reverse Dog Leg" modification, I will likely enclose
the baggage area with a sheet of plywood or Similar. I suppose I could change my
mind to extend this area, or at least some of it before covering. I fabricated little
brackets (tabs) to attach the plywood.

IMG_3059.jpg

Here's a close up of the brackets (tabs). Notice a nut plate is riveted to
each tab.

Fire Wall Fabrication

IMG_2908.jpg

I transferred the shape of the fire wall from the print to paper.

IMG_2910.jpg

Cut out the paper shape and transferred to cheap plywood, in this
case underlayment plywood. A person could also transfer the paper directly onto
the steel sheet, however I wanted to be able to sand the long edges of the
plywood straight, hopefully to result in a better fire wall final shape.

IMG_3103.jpg

Using electric cutting shears (Milwaukee brand shown here), makes it easy to cut stainless sheet.
I highly recommend using these.


IMG_3104.jpg

Debur using a fine file and emery paper stapled to a wood block

I plan to form a fire wall flange and attach it using rivets, next.
I tried putting beads vertically on the firewall, but the bead roller I
tried to used, couldn't form the bead well enough, so I'm
omitting the beads (stainless steel fire wall...).

Thank you for looking, but wait there's more:

IMG_2781.jpg

IMG_2018.jpg

And for fun, I included a couple of photos of my scratch built
Pietenpol AirCamper project I built. Due to the Cub project, this
project sets idle...

Thanks for looking,

John
 

Attachments

  • IMG_3058.jpg
    IMG_3058.jpg
    107.5 KB · Views: 171
  • IMG_3059.jpg
    IMG_3059.jpg
    94.7 KB · Views: 184
  • IMG_2908.jpg
    IMG_2908.jpg
    88.5 KB · Views: 128
  • IMG_2910.jpg
    IMG_2910.jpg
    43.8 KB · Views: 120
  • IMG_3103.jpg
    IMG_3103.jpg
    82.7 KB · Views: 114
  • IMG_3104.jpg
    IMG_3104.jpg
    64.1 KB · Views: 129
  • IMG_2781.jpg
    IMG_2781.jpg
    114.6 KB · Views: 159
  • IMG_2018.jpg
    IMG_2018.jpg
    107.6 KB · Views: 131
In that dog leg area I hinged the back baggage panel to the bottom floor and used a southco fastener at the top and can hinge it to lay down on the floor. But I put my elev. cables under the floor, so that is all a flat area, and that made it easy to do.
 
Scratch Building my Super Cub Update

Been working on the Upper Canopy Section, specifically the Bird Cage

IMG_5526.jpg

I built a short set of wings about 2' feet long, and clamped them
in place onto the fuselage. These are being used to define the profile
of the Bird Cage above the canopy.

IMG_5619.jpg

I spanned the canopy section using temporary cross members
to define the profile. Bending home-made piper channel into shape to
match the airfoil worked well, then clamped the piper channel to the
cross members. I aligned the piper channel (Bird Cage) pieces flush to the
inside of the canopy tubes (canopy longerons) so any final interior covers
will be flat. in this photo, the center piece of piper channel is not in place yet.

IMG_5621.jpg

Another photo of the fixturing. Notice the second (Charlies) Super Cub project
in the back ground, while we work on my Cub today.

IMG_5625.jpg

Here's a photo of the Bird Cage on the right side of the fuselage.
The first wing rib is also in view here.

IMG_5629.jpg

A view from above and behind. The next photo will be the trailing edge
of the Bird Cage fixture.

IMG_5623.jpg

I used straight edges to emulate the way the fabric will lay
on the fuselage while fixturing and welding the Bird Cage
in place. Happily, the actual parts and placement are matching
very well to the plans, indicating some accuracy.

Thank you for looking!

John
 

Attachments

  • IMG_5526.jpg
    IMG_5526.jpg
    124.9 KB · Views: 161
  • IMG_5619.jpg
    IMG_5619.jpg
    87.7 KB · Views: 143
  • IMG_5621.jpg
    IMG_5621.jpg
    92 KB · Views: 171
  • IMG_5625.jpg
    IMG_5625.jpg
    134.6 KB · Views: 144
  • IMG_5629.jpg
    IMG_5629.jpg
    85.8 KB · Views: 154
  • IMG_5623.jpg
    IMG_5623.jpg
    93.6 KB · Views: 160
John, I couldn't figure out how you were going to put a canopy on a Super Cub. Then I realized you were talking about the skylight! :lol:
 
Builders Update
- More on the Sly Light Area (Bird Cage)
- Fuel Line Mock Up
- Second Baggage Door


IMG_5735.jpg

Here you can see the stringers now welded in place above the
canopy (upper cabin, skylight section, bird cage,...)
Notice the wing attachment fittings are not in place yet, so the
leading end of the stringer is still free.

IMG_5713.jpg

I sheared and bent my own piper channel, and this is the method
I used to bend the air foil shape for the bird cage pieces.
Pass the piece through the hole, and bend gently. If you feel the
piece bend, you went too far. Gently!

IMG_5725.jpg

Match the air foil shape to the ribs. Here, I have
a bird cage stringer clamped to a rib.

IMG_5736.jpg

Here you can see the out board stringers welded in place,
and the center stringer clamped in place.
Although I am not ready to weld the wing fittings on,
I need to weld these stringers on, to continue to work on
the turtle deck stringers, as the turtle deck stringers will
fare into the bird cage stringers.

IMG_5735.jpg

Back to this photo. I have the fuel valve location selected,
and the valve is clamped into place per the Super Cub plans.
I want to have minimal interior, and I may even omit the sheet
metal tunnel over the throttle levers, but not sure yet. Here, I
sort of mocked up the fuel line locations using small diameter
pvc tubing.The fuel lines will be per plans using aluminum tubing.
Heat and bend the pvc tubing to shape for mock up.

IMG_5749.jpg

I framed up a second baggage door frame. I have the small
baggage compartment right behind the rear seat, with the
door low on the side of the fuselage. A small second area located
above the longerons and aft of the original baggage area will be included.
The wooden dowel is simply a mock up of the stringer location, and
will be replaced with aluminum stringers.


IMG_1754.jpg

And for fun, a photo from New Holstein Super Cub Fly-In 2013

thanks for looking,

john
 

Attachments

  • IMG_5735.jpg
    IMG_5735.jpg
    138.8 KB · Views: 173
  • IMG_5713.jpg
    IMG_5713.jpg
    73 KB · Views: 153
  • IMG_5725.jpg
    IMG_5725.jpg
    60.8 KB · Views: 134
  • IMG_5736.jpg
    IMG_5736.jpg
    87.8 KB · Views: 150
  • IMG_5749.jpg
    IMG_5749.jpg
    144.7 KB · Views: 163
  • IMG_1754.jpg
    IMG_1754.jpg
    108.5 KB · Views: 151
Builder's Update

Heel Brake Pedal Brackets
Turtle Deck Stringers
Lower Door Seal Flange

A few posts ago, I shared the fabrication process of the front heel brake reinforcing bracket. A spacer of sorts is needed between the bracket and the pedals themselves. Some planes use 1" aluminum or steel tubing for the spacers, while others use 1" wood blocks.

3.JPG

I elected to use wood blocks, however I laminated a three
piece block with a clear pine inside with aircraft plywood on
the outer sides. I'll bore out a big lighting hole prior to varnishing.

1.jpg

Laminating the blocks. Note I made enough for our two airplane projects.

2.jpg

Cut the blocks to shape on the table saw.
More to follow later.

IMG_5899.jpg

A lot of options for turtle deck stringers including
wood, extruded aluminum, rectangular aluminum tubing,
carbon fiber,...
I elected to use 3/4" diameter round aluminum tubing. Pretty light,
readily available from a hardware store, I like the large radius it will
provide as the fabric wraps around it, and relatively cheap.

The only problem is that I could only find them locally in 8 foot lengths.
I needed to lengthen them to 9'-9".

IMG_5730.jpg

I bought 3/4" diameter wood dowels, cut them
to 12" lengths, and applied 3 coats of spar varnish to seal them.

IMG_5808.jpg

I glued the dowel into one piece, let it dry, then
glued the 21" long extension onto the assembly,
and clamped the assembly to a straight edge.
I would do the same again as this worked very well.

IMG_5916.jpg

Here's a photo of how the aluminum stringer fits
up nicely to the trailing end of the bird cage section.

IMG_5879.jpg

For door gap seals, I sheared a folded over a piece of 0.025"
sheet steel. Charlie welded it to the door edges for me.

IMG_5909.jpg

The flanges will be covered with fabric when the door
gets covered. A foam seal can be added as well.
IMG_1811.jpg
And a photo from Supercub dot org New Holstein 2015

thank you for looking

john
 

Attachments

  • 3.JPG
    3.JPG
    143 KB · Views: 146
  • 1.jpg
    1.jpg
    60.8 KB · Views: 128
  • 2.jpg
    2.jpg
    50.6 KB · Views: 112
  • IMG_5899.jpg
    IMG_5899.jpg
    83.8 KB · Views: 141
  • IMG_5730.jpg
    IMG_5730.jpg
    33.5 KB · Views: 110
  • IMG_5808.jpg
    IMG_5808.jpg
    69.4 KB · Views: 115
  • IMG_5916.jpg
    IMG_5916.jpg
    80.3 KB · Views: 165
  • IMG_5879.jpg
    IMG_5879.jpg
    142.2 KB · Views: 150
  • IMG_5909.jpg
    IMG_5909.jpg
    46.5 KB · Views: 147
  • IMG_1811.jpg
    IMG_1811.jpg
    76.8 KB · Views: 133
Builders Update

Turtle Deck Stringers Attach Method to Cabin
Floor Board Tabs under rear seat
"D" Window Attachment Tabs
Bonus Photo

Considering that the turtle deck stringers are 3/4" dia. rigid aluminum tubing,
while the cabin structure is steel, I need a method to firmly and cleanly
attach the stringers to the cabin.

IMG_6041.jpg
The image above shows how the stringers will fare into the cabin.
A attachment method is needed on the left and right stringers.

IMG_6036.jpg
I'll use a similar method as I used on the center stringer at
the tail post, where a 5/8" dia. tube is welded to the tail post.
I'm referring this as a "socket connection".
The stringer simply slides onto the short post, and cotter pin
or pull rivet will likely be added.

IMG_6183.jpg
Here's a photo of the socket connection at the cabin where
the left side stringer fares into the cabin. Likewise, a cotter
pin or a pull rivet may be added.

IMG_6185.jpg
Finally, the three stringers in place.
I still need to bend in the trailing end of the left and right
side stringers into the vertical stabilizer, and I need to attach
the leading end of the center stringer to the cabin.

IMG_2436.JPG
Recall I fabricated small saddles to attach the stringers to
on each turtle deck bulk head. A pull rivet will be used for final attachment.
To be clear this photo was taken when the fuselage was laying sideways,
and this is a photo of the bulk head in rear of the fuselage directly
in front of the tail post.


Floor boards Tabs Under Rear Seat

I'm considering the battery location to be under the rear seat, and
potentially a small bin also under the rear seat to store of few small items.

IMG_6179.jpg
Two small pieces of 1/4" Birch Plywood floor boards
may set on these tabs. Two separate floor boards are
needed sue to the elevator cables run down the center
of the fuselage very close to the floor. A battery ground
lug will be needed in this area as well.

"D" Window Attachment Tabs

IMG_5904.jpg
Plexi-Glass window panels will be used, with an
aluminum sheet metal trim piece covering the
leading edge. The trim piece will also be used as
a gap seal for the upper door (upper window if
you prefer).

tabs.jpg
Three tabs welded in place along the cabin posts. The plexi-glass
will slide into the "D" window frame. A decorative trim
piece will be bent to cover the outside of the post and tabs,
with a small flange to serve as a gap seal for the upper door.
The gap seal will likely include a small rubber bulb for the seal.
Although two tabs are plenty to hold the parts, I added a
center tab to keep the trim piece from flexing outward.

IMG_6043.jpg
A look at my project.

J Norris Cub.jpg
Bonus Photo - Supercub dot org member Joe Norris's
Super Cub with Joe pushing it into the sun light.

Thank you for looking!

John
 

Attachments

  • IMG_6041.jpg
    IMG_6041.jpg
    98.3 KB · Views: 132
  • IMG_6036.jpg
    IMG_6036.jpg
    74.4 KB · Views: 141
  • IMG_6183.jpg
    IMG_6183.jpg
    56 KB · Views: 140
  • IMG_6185.jpg
    IMG_6185.jpg
    79.1 KB · Views: 131
  • IMG_2436.JPG
    IMG_2436.JPG
    132.1 KB · Views: 154
  • IMG_6179.jpg
    IMG_6179.jpg
    61.9 KB · Views: 122
  • IMG_5904.jpg
    IMG_5904.jpg
    78.3 KB · Views: 130
  • tabs.jpg
    tabs.jpg
    131.4 KB · Views: 140
  • J Norris Cub.jpg
    J Norris Cub.jpg
    88.5 KB · Views: 131
  • IMG_6043.jpg
    IMG_6043.jpg
    144.6 KB · Views: 147
Stringers,
If most of the spring is out of the tube, I would consider not using the pop rivets in favor of a structural adhesive. This could be as simple as a structural contact adhesive such as used with the Stewarts fabric system or stronger if you need.
Obviously the expansion rate is considerably different between the stringer and frame. I would be sure the tube can not walk off the end tube and utilize tie wraps to retain the bonded tube in the saddles till the fabric is going on.
The adhesive should also provide the material separation to reduce the chance of the aluminum from corroding away.
 
Back
Top