Building Electric-Powered Bicycle Camper - 270+ KM Range (PART 2)

[@Bicycle_Fungi]

Nice work on the Aluminum welding.

[@Jerbrown]

Thanks - welding is a very gratifying skill to learn and put to use :)

[@normandgallant8106]

I took a welding course around 2009 but I can't weld ....I was gonna continue with robotics welding but did not . If you have specific questions , about welding , I will gladly enjoy anwsering them , I mostly focused on aluminium and SS for boats . Are you tempering your welds ? Copied from googling Do you need to heat treat Aluminium after welding? After the welding process aluminium weld lose some mechanical, microstructural properties. It becomes 30-40% weaker as compared to parent material. To improve these properties post weld heat treatment is carried out after the welding. Welding for static structure is way different than dynamic struture

[@rossmacintosh5652]

Hi Jeremiah! After watching your camper build videos KZbin recommended to me the second e-bike camper build by the 'Drew Builds Stuff' channel. If you haven't already seen it I think you might find it helpful: kzbin.info/www/bejne/e5Olh6GrjduZhLM While Drew isn't dealing with a heavy battery like you plan to have, he is using a relatively lightweight approach to the trailer construction that I know has been time-tested in the teardrop trailer community. Countless trailers constructed like his are pulled by cars & motorcycles at highway speeds. His hitch however looks not nearly heavy-duty enough to me. I note that near the end he recommends not using the 20" fat tires he used due to rolling resistance. They did however effectively give the trailer some suspension. You can see the trailer bouncing along in use. Seeing that bouncing makes me think that ideally a trailer would incorporate some form of suspension. Doing so might save the trailer from vibrating itself apart on your expedition and save on wear and tear.

[@Jerbrown]

Hi Ross, yes. From my early prototype tests, I determined suspension was essential. I'm using torsion suspension half axles on my build. I tested them under load, and they worked great! I'll have another video showing some test clips. I have followed Drew's two videos closely, and I'm considering all options.

[@Jerbrown]

Also, thanks so much for offering your insights!

[@rossmacintosh5652]

@@Jerbrown All the videos I've seen with foam construction use the extruded pink boards (XPS). I assume those using it aren't familiar with poly-iso insulation boards. They are commonly used in commercial low-slope roofs. One manufacturer in Canada is IKO. They have a higher R value than XPS, are seemingly denser, and are more rigid. They are also sold with glass fibre facings that are super smooth (perfect for epoxy resin application?). They are sold in various thicknesses. One thought I had was two thin sheets epoxied together would be very strong. I suppose third layers in high stress areas would add even more strength without significant weight. The interior and exterior faces of such a composite panel could receive epoxy resin and finished with a 'gel-coat' for a very professional result. I really think a cabin shell could be made that way without any additional framing. It seems well suited to an angular design like you planned.

[@Jerbrown]

@@rossmacintosh5652 Very good idea... I came across a dirt cheap acquisition of Aluminum Composite Panels and my plan was to weld the upper cabin shell frame with aluminum 0.75"x0.75"x0.125" square tubing. Then apply the ACP sheets for the exterior cladding. Then use the pink (or your suggestion) rigid foam (3/4") on the inside for insulation and added rigidity, bonded to the ACP panels. I admit, I am rethinking the upper cabin and I have not decided what route I'll take yet. The ACP panels and additional aluminum framing definitely add weight, but I can still stay under 400 lbs by my calculations. My thinking is that it might also keep the bears out a few seconds longer while I scramble for my bear spray....

[@rossmacintosh5652]

@@Jerbrown I have used ACP on several architectural projects. It is a very interesting product for something like your cabin. One fabrication detail used with ACP is to router a v-shaped groove on one side (cutting through only one aluminium face & into the polyethylene core). The panel can then be folded up to 90-degrees. That technique can be used to form edge flanges. Two such flanges can then be easily riveted together with butyl tape between the two flanges. Such panel-to-panel joints add incredible rigidity to the panels. Typically when used architecturally all fasteners are hidden using pop rivets, screws, and sometimes even industrial adhesives. When used on buildings, the panels are typically formed into pans (with the folded edges) and the edge of the pans fastened to aluminium rails & clips. The manufacturers specify the maximum sizes of fabricated panels. They do so to minimise unintentional & unattractive problems like 'oil-canning' of the panels where they deform from wind load. The sheet sizes manufacturers sell are much larger than the finished sizes of fabricated panels made from the sheets. Thicker sheets typically can be used to fabricate larger panels. When installed architecturally the panels typically act as a "rain screen" that is not waterproof. Water is allowed to get behind and is effectively drained from the cavity. (In that it is similar to brick cavity wall construction). I'm assuming you need your skin to be waterproof! I do think you could relatively easily do that with ACP. I also think you'll find you can make it rigid enough without a full welded aluminium frame. I'm thinking it might make sense to make a tubular aluminium door frame to support the door. Such a door frame could be stabilised by extending both jamb tubes up and over to the opposite side of the cabin in a roll cage kind of fashion. A partial frame like that could reinforce the entire cabin. Also be aware that even after you fabricate the primary shell, with ACP construction you can still easily add reinforcements made in ACP to the interior side to increase rigidity.