'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.