Picnic Unit - Vellfire

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Our ATH10 Toyota Alphard hybrid with picnic units was a huge success.  When the time came to replace it, we decided on another Toyota Alphard Hybrid.  Well, at the time of purchase, it was the Vellfire version which came up for a good price at auction in Japan.  As before, the hybrid has highly desirable 4-wheel drive and a set of sockets for 100 VAC 1500 W (operative only while the engine is running, however, not when parked-up).  This time, I opted to design and install a simpler picnic unit.  Experience found little use for the sink or the microwave, while the fridge was always too small and the portapotti a little on the low side.  Figure 1 shows the new design for the Vellfire, installable either across the rear of the car or down one side on a separate base plate.  The shelves are standard 18mm thick chipboard with melamine veneer (green), 400mm wide, the uprights (light brown) are 18mm thick pine, and the base is 18mm marine ply (dark brown).



Fig. 1: New picnic unit design


A nice large 35 litre Dometic fridge (blue), Hunnersdorf wide mouth water bottle (grey) and a Bosch Tassimo coffee brewer (pink) sit on the top, a leisure battery power pack (light green), evaporative air cooler (mauve), and portapotti (yellow) sit on the bottom.  Outside the unit, to the left is a torroidal step-up transformer to take the 100V to 230V (grey) and to the right a fire extinguisher (red) and small Bosch battery vacuum (green).

As before, the installation is reversible with a new approach to the use of the seat tracks in the floor.  The trick was the discovery of a rhombic nut to fit into the floor track.

The "T" track is around 18 mm wide and around 18 mm deep, more robust than the earlier Alphard track.  It takes a standard 18 mm "T" nut with the nut sides shaved by around 0.3 mm all round for an easier fit (a 14 mm nut also works perfectly well).  The nut drops into place in the track and is then turned 45 degrees to lock it in place.  I designed and 3D-printed a keeper which would hold it locked while the unit was lowered into place and the M10 bolt inserted.  The STL files for the 14 mm and 18 mm keepers can be downloaded.  Figure 2 shows a sequence of photos illustrating the fit of the nut to the track.



   Fig. 2: Rhombic 17mm "T" nut with 3D-printed keeper and M10 mushroom roofing bolt cut to length


Figure 3 shows the unit in place in the rear of the van with the picnic equipment.


Fig. 3: Unit in place


While the shelves are screwed to the uprights with 60mm or 100mm #10 wood screws, the uprights are attached to the base using M6 bolts and barrel nuts, details shown in Figure 4.  They can then be attached to either the rear-facing base, as in Figure 3, or the side-facing base, shown in Figure 5.  Shelves are fitted with edge strips to stop contents from sliding out.  Errors in initial bolt hole placements all too obvious (smile)....


Fig. 4: Unit construction with screwed shelves and M6 barrel nuts for uprights


Side-facing base as in Figure 5, initial errors in hole placement pretty obvious.. 


Fig. 5: Base for side-facing
(Note cut-out for rear seat floor traveller, and additional base area to carry (a) a third fixing bolt, and (b) the transformer.)


Finally, the uprights for the fridge needed apertures for the power cable.  I knew this time to make sure the fridge was dual voltage, 12V as well as (a welcome universal) 100V-230V.  This Dometic CFF 35 fridge has the very welcome feature of top opening either from the front or the back.


Fig. 6: Portable fridge power cable access aperture
(Note the notch in the rear of the upright, needed to clear the folding rear seat when the unit is side-facing.)


For portable power we invested in the "TotalCool Totalpower" 500W Lithium unit giving sockets for USB, 12V, and 230V.  It had a truly eye-watering price, but again previous experience emphasised the value of dependable off-grid power.  TotalCool make a neat compatible solar panel for, erm, future investment.  For immediate investment we decided on the evaporative air cooler (Google "TotalCool").

We wanted a towbar for our bicycle carrier.  There is no suitable towbar on the UK market for Toyota AYH30 or ATH30 cars.  I sourced this kit from Thailand with the help of a Thai friend, and it was happily installed by my local garage.


Fig. 7: Towbar
(Google "Masterhook")



Previously, I had thought Airlink had gone out of business, but their step-up transformer is available again, albeit at a very substantial increase in price.  There is nothing else on the market which does its job so well, so that's that, as they say.

Previously, the Webasto auxiliary heater needed to be run up every 2 or 3 weeks for 10 or 15 minutes to prevent the petrol feed from gumming up.  When it worked, it was brilliant -- a toastie warm Alphard on a winter's morning, absolutely fabulous.  When it gummed up, well, that was a pain.  After deep soul-searching, we have not installed an auxiliary heater in the Vellfire.


2023 Lester Gilbert