Stainless Steel Micro-Airstream behind motorcycle

[ST1100]

Maybe this could be a solution for the roof corner problem.

The radius of the corners is 300 mm. So the outer length of one roof segment is 471 mm.
The square angle will be on top of the roof.



If I cut a sheet of 471 x 471 mm in this way it could lay one segment over the other like they did it at the front shell of vintage airstreams.



Then rivets and sealing with liquid from inside.

I will test it with cardboard and if that works with a sheet of aluminum.
Or better draw the lines on one eighth of a 60 cm diameter plastic ball and cut it !

Tom

[alaska teardrop]

Tom,

That's a cool design you're working on. I look forward to watching your progress.

I also build trailers using metal for the cabin structure. Here is a link to an all aluminum cabin that may give you some ideas for your build: viewtopic.php?f=27&t=51991

Fred

[alaska teardrop]

Tom, can you say who is supplying the axle/chassis for your trailer? It looks very interesting, particularly with proper dampers incorporated.

I like the 'separate box' idea - we in Britain will also have problems with using approved windows when we have to pass our own test.

Hi Andrew,

I wonder.

Does the 'we' in this statement portend that there may soon be a new trailer from England of your very own design & construction? After these years of research & helping others, I think it would be wonderful to see it happen.

Fred

[ST1100]

Tadaah !!!

A lightning struck me in the bathtub while thinking about my quarter hemispheres !
Every day I walk on the surface of a sphere !



Take a earth water ball with 60 cm diameter, the lines are printed on.
Cut it from the north pole through Greenwich to the equator, then eastward 90 degrees and then up through China and Russia back to the north pole.
Leave the north pole as connection, but cut every 15 degrees from equator to the ice cap. So you get six panels
Lay it on a sheet of aluminum and sign the outer lines, give 20 mm for riveting only to the western borders.
Thats it !

[ST1100]

Tom,

That's a cool design you're working on. I look forward to watching your progress.

I also build trailers using metal for the cabin structure. Here is a link to an all aluminum cabin that may give you some ideas for your build: viewtopic.php?f=27&t=51991

Fred

Hey Fred - thanks for the link to your building blog - your riveted connection of the alu tubing is like I want to realize it, because I've nobody to weld it for me.
Fine to see that it works !

Thank you - Tom

[RandyG]

Never thought of doing it that way, but you may think about sealing between the overlaps. A faying layer of sealant and shooting rivets while it's still wet. We do that on jets and it almost act like a glue but that method, done with the right sealant, could be air tight.

[mezmo]

Maybe this could be a solution for the roof corner problem.

The radius of the corners is 300 mm. So the outer length of one roof segment is 471 mm.
The square angle will be on top of the roof.



If I cut a sheet of 471 x 471 mm in this way it could lay one segment over the other like they did it at the front shell of vintage airstreams.



Then rivets and sealing with liquid from inside.

I will test it with cardboard and if that works with a sheet of aluminum.
Or better draw the lines on one eighth of a 60 cm diameter plastic ball and cut it !

Tom

Hi Tom,

If you use this method, I recommend you drill a hole at the top end of each of those
radiating lines, @ 1/16th to 1/8th inch diameter [obviously use your metric equivalents]
- or your rivet's required hole size - up by the top corner. This should prevent the metal
from ripping or cracking at that spot/point as you bend it into position and help the
top corner form a shallow cone section as you bend and form the end caps. I had to
recently fabricate a section of ductwork for an in-progress home project and this hint
helped me form the shape I needed - my first attempt at making a 3D shape from sheet metal.

Also, I was using very thin aluminum [Flashing stock, I doubled it and riveted the two
identical pieces together to get the thickness needed for at least some rigidity.] that
I cut by repeatedly scoring with an utility knife along a metal straightedge [a framing square
leg] at the cut line. I don't know if SS would allow you to do that reasonably easily or not,
but it gave me straight flush cuts with no deformation that would have been caused by
using metal shears. [I don't have access to a metal brake or guillotine style sheet metal
cutter, so I had to do it all by hand and 'by guess and by golly'.]

Cheers,
Norm/mezmo

[GuitarPhotog]

I don't know if SS would allow you to do that reasonably easily or not,

Stainless is not going to be that easy to cut, drill, or bend. You'll be surprised how many drill bits you wear out just drilling rivet holes.

<Chas>

[ST1100]

Thanks for the hint with the holes at the top end to prevent the cuts from getting deeper from vibrations.

I'm experienced with drilling stainless steel. You need an exact center-punch, cobalt drills, good cooling and low speed.
If you be careful with the drills and cool with oil, they stay verrrry long.
The sheets are only 0.6 mm thin. Normally I work with 1 to 2 mm stainless steel.
And I will drill the stainless sheets on my workbench and clean the holes at the inner side, so that only the aluminum ribs have to be drilled easy at the assembly.


Possibly it will be better for my roof corners to take six single panels with a constant overlap of 20 mm and not to center the apexes at top of the corner.
The Airstream on the picture is a good example. The tile apexes center at the front and rear end of the body.

So I take my six vinyl globe sheets and cut through the north pole.
The first five segments will get 20 mm overlap at the upper side and will be rivetet from the bottom to the top.
The sixth segment get no overlap and will close the roof. So they lay like roof tiles.

This will be the best for all the body sheets. Working from bottom to top and from the end to the front for maximum rain tightness.
20 mm overlap will be perfect as my framework tubes are 20 x 20 mm. So if I drill 10 mm from the outline I meet the ribs perfectly centered.



Has anybody experience with a good thin self-adhesive sealing tape for my seams ?

Tom

[alaska teardrop]

Tom, I use 3M VHB tape #4919F between the aluminum sheet & all of the tubing. I buy it from a local industrial adhesive supply company.

Here is a link to the product description: http://solutions.3m.com/wps/portal/3M/e ... &x=11&y=13

Fred

[ST1100]

Drawing a segment of a hemisphere !
(sorry for my preference of metric distances)

There is an article in Wikipedia called Longitude http://en.wikipedia.org/wiki/Longitude#Length_of_a_degree_of_longitude

Here is a table on the right which shows the distances on earth at a defined longitude for one degree latitude.
My quarter hemisphere is 90 degrees wide, so each segment are 15 degrees.
The radius is 300 mm so from equator to pole the distance on the surface of my roof is 471 mm (10000 km on earth).
15 degrees on the earths equator are 1670 km so on my roof 79 mm.

Using such a table for the earth with 10 degrees difference in latitude i can calculate the wideness of the six roof panels.
At the base on the left side the panel is 7.9 cm wide and at the apex on the right side zero.



Drawing this on cardboard I can transfer the panels on a aluminum sheet plus the overlap and start a test.

By the way, I learnt today, this was invented by the german Martin Waldseemüller, who produced 1507 first a globular world map and a large 12-panel world wall map (Universalis Cosmographia, both bearing the first use of the name "America"). He thought Amerigo Vespucci discovered the new continent, not Christopher Columbus.
Without that guy you all will be no Americans but Columbians or Christophians !!!

http://en.wikipedia.org/wiki/Waldseem%C ... _map#Gores

Tom

[ST1100]

Tom, I use 3M VHB tape #4919F between the aluminum sheet & all of the tubing. I buy it from a local industrial adhesive supply company.

Here is a link to the product description: http://solutions.3m.com/wps/portal/3M/e ... &x=11&y=13

Fred

Hey thanks Fred - perfect tip - I find it on ebay.de in 12 mm x 0.8 mm for 11 Euro per 66 meter (3M VHB 5386 F Doublesided Tape 12mm x 66m)
Hope to find it 0.4 mm thick here in Germany !

Tom

[droid_ca]

just need one of these for it as well

or better yet


hopefully the picture gives you an idea of how to do your riveting and your curves

[ST1100]

hopefully the picture gives you an idea of how to do your riveting and your curves

Oh wow - a pure steampunk sidecar - flawless design & finish !



I'm sure, I cannot deliver such perfect quality, but I will do my best !

[ST1100]

Okay - next step:

Using my yesterday table I drew one of my roof corner panels on paper, so I can transfer it six times to an aluminum sheet.

Six of that panels should build a perfect quarter of a hemisphere. only for the apexes I have fo find a better solution.
Possibly I should cut the apexes and place a small quarter circle on top of that corner.



Hope to find a box from my axle manufacturer, when I will be back home tonight !

Tom