Upgrade ideas for the "new" TM

[Larryjb]

I don't think replaceable panels would give the required strength. I have found that the panels don't have studs, but get their strength from single sheets of aluminum permanently glued to Styrofoam.

I think the overall strength could be improved if the ends of each shell were made of a single piece of tubular aluminum. You may have to use 3 pieces (2 verticals for sides, 1 horizontal for the roof) welded together. The open sides of my upper shells are quite floppy. One shell is actually bowing out quite a bit. I'll post pictures later in a separate thread.

[Padgett]

" battery-assisted start, you must have a full inverter, and synchronize the frequency to the AC of a generator (which is going to be changing in frequency under load as that happens)."

Understand that but my thought was simpler: AFAIK a generator/inverter goes through three stages: motor driven AC, rectified DC, inverter to AC. Since there is a 12v DC pickoff for charging a battery, that made me wonder if stage 2 is 12vDC. If so why not plug a 12v battery there to smooth the momentary surge. Couple DC not AC. Of course it may still overload the inverter but my observation was that without any assist the genset would start the AC occasionally. In those cases the voltage would drop to 95-105v and then recover. When it stalled the voltage would drop below 75v and it would not recover. This led me to believe that the overload trip was not immediate and took a second or two.

That is when I tried delaying the fan to reduce starting current by a few amps. This helped but the long stroke Predator still had trouble ramping up quickly.

Now I am sure there may be a reason I don't know why connecting the 12v coach battery to the 12v charge point on the genset won't help but unfortunately my AC has the soft start installed so cannot test that way and a desperate friend now has my 15k test unit so am left with theory and not reality.

[Larryjb]

After being out a couple of times, and checking out interiors of other trailers, the one thing that my wife mentioned was the bathroom layout. It would need to be slightly larger but, and I agree with her, standing in front of the bathroom sink is very uncomfortable, especially for shaving. If it were slightly larger, you could locate the sink so that you could stand in front of it. For larger people, it is quite cramped for drying and changing.

I realize the space would have to come from somewhere. Perhaps the small bathroom would remain in the smaller trailers (2720 and below), and the larger trailers could have a slightly larger bathroom? My wife does really appreciate that the toilet and sink are not in the tub, like it is in the smaller versions.

We used our 2720 so far with 3 adults and two kids. Pretty cramped, but doable. We'll see how it works next time with just 2 adults and the kids.

[linuxman]

Originally Posted by BrucePerens

[The TM design] is so due for an update that I question the value. The update I have been thinking of:

Uses an aluminum I-beam frame with fiberglass-foam panels between the frame members and bolted joins rather than welds.
Corners are angles rather than I-beams.
Easy to replace panels and beams.
Roof elements like solar panels bolt to beams, rather than panels.
Wiring is sandwiched between panel edges and beams.
Lift arms pivot at a journal bearing below the shell edge rather than using pockets, and provide better horizontal stability. Similarly the lift arm is supported by a split journal bearing at the end of the torsion rod.
Peak in roof enforced at beam join down roof center rather than being a curve of a foam panel.
Internal aluminum chassis, not box-on-a-trailer.
Lower 1 foot (inside diameter) below floor (fully enclosed) dedicated to infrastructure and storage, floor above that.
External steps set into below-floor area rather than hanging from bottom of trailer. One or two internal steps built in at door.
Shells overlap the below-floor area when closed.
AC, tanks, batteries, heaters, wheel wells, plumbing, spare tire, wiring, gas piping, converter, solar controller, torsion bars, water fills and valves all in below-floor area and fully enclosed except for necessary ports to outside.
Below-floor area is insulated using foam panels and keeps plumbing above freezing for 4-season use.
Actual bottom of the trailer is flat and featureless.
Solar panels are most heavy thing on roof. No AC on roof.
Ledge at bottom of below-floor area for shells to rest upon when closed, protects them from road dirt and provides structural support along the entire area of the lower shell edge.
Probe and drogue latch system for shells with cable release. One lever to release shells.

Now to cut costs and simplify adding a few things on here and some changes:
Yes to the enclosed structure below to replace a heavy metal frame using aluminum alloys for big weight reduction.
Yes to aluminum framing all out and even on the roof but incorporate them within the SIP styled panels you'd change to using for all panels for floors walls and roof for strength and tie points but keep the completely glued foam within as that adds massive strength with very little weight.
Yes to putting some kind of easily replaceable air system based in the bottom structure that is the flexiframe(invented new word for Bruce).
Square edges get rid of all the front and back rounded and bulges and make it much easier to attach to each other and easier to work on after assembled.
Having the shells on a ledge like was suggested also could lead way to electric rams to actuate the shells raising and lowering and completely contained in the lower bulkhead.
Much lighter and about the same size basically and way more modern.
Glamping versions with no trifuel options just AC appliances and 12volt lighting.
This original was 9 yrs ago and now you have even better construction options available to consider.
Aluminum isn't lower costing but the changes I give would make it much faster to assemble and labor is very much a factor in costs these days.
Torsion bar axles instead of thru axle would lower the weight as well and the lighter you make it the higher your gross weights can go.