'68-'73 Pop Top Cot to Bed Conversion
by Michael Benthin
[Editor's Note: Mike describes the procedure for installing the Westfalia foamboard bed (found in
some European models in place of the cot typically found on US imported '68-'73 poptop campers).
The advantage is a larger, more comfortable bed, without the need to make the more extensive
modifications for the alternative solution: to install a '74-'79 style poptop.]
There were queries on the detail of the Europeam option foamboard bed to
replace the cot on top. Details with drawings follow: (printout is easier)
The stock 57"x38.25" board had hinges at the front corners made of two
pieces of rightangle steel on the board and two corresponding pieces
screwed to the roof under the poptop front. These lifted the board high
enough at the sides to allow for curvature of roof in front. I did find
these; they are galvanized "L's" bent at 77 degrees , and the hole for
hinge bolt pivot is 1"7/8" off the roof. If flattened it's shape is: (side
of bed view)
FRONT | | | bed board /
: ___ :
Fixed hinge on board : / o \ : pivot hole with binding nut on bolt
/---------\ 77 deg bend here
bolts to roof / o o \
at holes /_____________\
It also had at least a pair of large rubber "feet" about 1" in diameter x
1.5" high at sides of board that rested on opening sides and made+ the
board level. It also had 2 "forks" (looks like end of tie rod fork) that
were screwed to edges just where the poptop roof grabbers could slip into
them to hold board up out of way when standing in bus. I don't have all
the hardware anymore, but looked at the board, and the holes for the
grabbers have nuts "glued" inside (probably countersunk under the foam);
same for hinge area. I'm sure that in use, one had to lift the top first
(so you need the 10" or so gap at rear to push up top and climb up there),
then push up and latch the board.
If I were designing this,
- I'd measure the distance from front
(where it'll fit with poptop down) to where board will end - for skinny
people, can be less gap, for larger people, bigger gap! Also measure
maximum width (with top down) that a board will fit overlapping opening.
- Cut the board out of at least 9/16" plywood (the good stuff, not
sheathing; good stuff has no voids). I'd test for board strength by laying
edges on two studs and lying on to see how much it gives. Round sharp
corners. Test on roof opening to see if rear opening is big enough to let
you open roof & climb up onto board. I suspect you can use a thinner 3/8"
-1/2" board if you beef up the edge at rear with thicker piece glued
underneath or steel angle iron.
- Make hinges from sheet steel at least
1/16" thick- bolts thru whole board would be stronger; or possibly you
could buy the 1" wide flat bar stock long enough to just bend down ends for
hinge pivot and drill a bunch of screw holes to fasten it to board. You
can use aluminum 1/8" thick for this (4-6 ft long)' long...Use just a few
screws now, since you will screw this over fabric later. Would let you use
thinner board (1/2") also. I'd make the entire hinge with pivot holes and
hinge bottoms already bolted (with "binding" nut) to board, then put board
in opening LIFTED up so you can see hinge bottoms, and mark holes for hinge
bottoms on roof- (or measure very well & transfer to roof;remember it's
curved!) -get rid of board, drill the holes for either sheet metal screws
or bolts thru roof (must pull canopy board for this). I'd use cap head
bolts/screws so if it's a tight space (even with board lifted), you can use
a flat wrench to fasten it down or hold while applying nut below. Mock up
the board (don't tighten hinge bottoms yet).
- Locate grabber locations and fabricate something for them to lock board
up- Me, I'd use a eyehook bolted to center of board and sash cord left
tied across poptop supports at top- just hook over the eye- especially
since lots of tops have the grabbers rotted out!
- Also check for
leveling supports near end of board; add some to middle if it sags.
Doesn't have to be rubber, could be plywood blocks screwed to bottom?
- Check for clearance to roof and get some foam (1.5 -2" thick"?). Get
some upholstery fabric at the same time allowing at least 5" extra over boa
rd dimensions. (check store for endies, can be any HEAVY fabric). If you
don't have it, get staple gun or lots of uphostery tacks. Take board down
(you left it loose, right?)- and lay down upholstery, then foam, then
board. You know the routine, bend up sides of fabric over board, tucking
in an underlap, staple/nail all along one edge. Do opposite side. Do
front, rear. TAPE Mystic tape over all the staples. If you used the flat
bar stock with bend ends for board hinge, it's easy to put it back over
fabric now with lots of screws. It must be within 1" of edge, or board
will hit roof when lifted! Add the spacer blocks and grabber holds if any.
- Muscle all this up there and fasten the hinges to roof. Voila, a
bigger bed! For long people, the extra board I put in had cutouts for the
roof arms and dropped across opening once you were up there. Would be
easiest to add extra foam for this with fabric stapled to thin (1/4") board
which is then GLUED to the across board with some kind of rope loops at
sides to help pull out the board. Make sure the foam really butts agains
foam on bed, since this is your head end; pillow will lay on this anyway.