©By: John T. Blair (WA4OHZ) 1133 Chatmoss Dr., Va. Beach, Va. 23464; (757) 495-8229 Originally written: circa 1993 Last updated: June 7, 2009
When I bought my Morgan, my dad used to joke about needing a cabinet maker because of all the wood. When I describe the car to friends, they always kid about having it covered by a termite contract. I think the best joke about the car came from a co-worker, "buy a real car and save a tree!". This leads me to the topic I'd like to talk about in this article: restoring the wooden body subframe.
The factory did not seal the wood very well. When my car was totaled
22 years ago, I had to replace all the woodwork behind the doors except the
right side rear fender arch. I sealed all the new wood (left fender arch,
inner panel, etc.) with a wood primer/sealer but did not touch the right
side wheel arch and inner panel. The car left the factory in December
1965, making the two fender arches 3 years different in age. When I
removed the skin, I found that the treated wood was in great shape (no rot)
some 25+ years later. The untreated wood is a different story. The back 2
inches of the fender arch has rotted away and the inner panel must be
replaced. This time I wanted to seal the wood forever so I used the WEST
system epoxy.
The firewall was removed from the wood subframe by removing the
numerous wood screws around the perimeter of the firewall and the 2
hex head bolts that hold a steel stiffening bar to the firewall and wooden
frame. Now comes the hard part, removing the sheet metal skin from the
wood. The skin is held to the wood by a few screws and a LOT of nails.
Removing the nails turned out to be a real chore. I spent hours trying to
remove them with diagonal cutters (broke 2 pairs of them) and end cutters.
Next I tried modifying a screwdriver by grinding the blade to a sharp
edge. I was hoping that I could drive the screwdriver under the sheet
metal and pop the nails up enough to grab them with the dikes. This worked
better than just the dikes, but not as well as I had hoped. The next
approach was to use a dremal tool to grind off the heads of the nails.
This didn't work at all. I kept cutting into the sheet metal. Regardless
of the method I used, I couldn't work at this for more than 15 to 20
minutes before I got so frustrated I wanted to take an ax to the whole
thing.
After all the sheet metal is removed, it is time to start removing the screws which hold the wood subframe together. Removing some of these screws can be a real problem. Here are a few hints to help a screwdriver get a better bite:
The wood subframe can be separated into two parts. There are 2 screws holding each of the rear arches to the door sill plates, and 2 screws holding the rear quarter panel frame to the sill plate. The figure shows the basic wood subframe and the size of the screws holding it together.
To separate the two fender arches, start by removing the wooden U
formed by the rear chassis mounts which are attached to the rear inner
fender panels and the rear cross brace. Be careful as this U is relatively
fragile. The fender arches are attached to the chassis mounts by three
screws (6b). It may be necessary to use a rubber tap hammer to remove the
fender panels from the groves in the chassis mounts. This U can now be
disassembled by removing the 2 screws that hold the cross brace to the
chassis mounts. The trunk rack and the spare tire rack can be removed
by unscrewing the nuts on the carriage bolts and removing them.
I had to make several new wood parts: trunk back, trunk deck, the door sill plates, right rear fender well panel, door panels, and the gas tank bed, floor boards. Most of the replacement parts were initially cut by using either a band saw or saber saw. Final shaping was accomplished by clamping a template (either the original part or a poster board pattern) to the part and sanding the new part with a 1" belt/disc sander until it matched the template. To make the new front floor boards, I purchased some poster board to make patterns. I measured the chassis and sketched it on the poster board and cut them out. Once the patterns fit, they were traced onto a piece of 1/2 inch of CDX plywood and cut out using a saber saw. I made one minor change from the original floor boards. The factory cut them so they laid next to the little fore/aft stringers that the transmission bracket mounts to. Instead, I increased the width of the floor boards so they laid on the stringers. Since the stringers are not flush with the bottom angle of the chassis, the floor boards were notched to accommodate the height of the stringers. (The notch was made by making several cuts on a table saw with the blade set to the height of the stringer.) Since the new floor boards go completely across the angle iron stringers, the floor boards must be notched to fit around the transmission mount bracket and the emergency brake hardware.
The seatpan part of the floor boards was also modified. Originally it
consisted of 2 pieces with a cutout in them, apparently to allow access to
the grease fittings on the rear U joint. Since the new U joints I
purchased did not have grease fittings, I decided to make the seatpan one
piece.
The right fender arch had lost the back 2 inches or so due to wood
rot. The front lip, where it bolts to the sill plate, also had rotted, and
the inner panel had to be replaced. The new inner panel was made by
tracing the outline of the old panel on a piece of 1/2" BCX plywood and
cutout using a saber saw. (The original panel was 3/8 inch plywood. I had
intended keeping it stock. Somehow I just blew it. However, after getting
the new panel made, I decided that the extra 1/8 inch would not make that
much difference - I hope!) The final shaping was done using the belt/disk
sander. Using the transfer punch set, I marked and drilled all the holes.
Next, 2 coats of epoxy were applied and sanded. To repair the arch, I
started in the back about 2 inches forward of the rot and drew a diagonal
line (about 4 inches long) across the arch. (This would give more surface
area for the patch to mate to.) The rotted section was cut off using a
band saw. I bolted the side panel back on so the angle between the panel
and the fender arch could be measured using a protractor on a ruler
(similar to a combination square). Once the angle was drawn on a 3/4"
piece of oak, it was set on the fender arch and arch lines were extended
using a yardstick. The patch piece was cut using a band saw. Next, the
fit was checked by setting it in place. The final shaping was done
using the belt/disc sander. When a good fit was achieved, the patch was
clamped to the arch and 2 holes drilled so the patch could be screwed to
the arch. Everything was disassembled again and epoxy was applied to both
the patch and the arch, and the patch was re-screwed to the arch. The
entire arch was coated with 2 coats of epoxy. The front lip was rebuilt
using epoxy and a filler to thicken it. I placed masking tape around what
was left of the lip, to form a dam, and applied the thickened epoxy to the
damaged area.
The firewall attaches to the front of the wood subframe. This wood is composed of 3 separate pieces with a small piece of plywood inserted between each vertical piece and the horizontal piece. I cleaned up the slots with a milling machine. However, they could have been cleaned with a table saw. To make the braces, I inserted a piece of poster board into each slot and traced the outside of the wood. I cut out the template and traced it on to some scrap 1/4 inch plywood and cut them out using band saw. The final shaping was done using the 1" belt/disc sander.
The last piece, to be made were the 2 curved pieces that support the
sheet metal rear deck and fit on the outer edge of the fender arch just
behind the cross brace. To get the curve, I used a curve tracing tool
(made up of a lot of little rods held together by a cross brace). I
placed this on the fender arch and tapped the top to get a nice fit. This
curve was then traced on a small block of wood. The height of the cross
brace was measured and transferred to the block of wood and the upper curve
was sketched freehand. I used a band saw to cut the part out. Final
shaping and smoothing was done using a drum sander chucked up in a
drill press.
Enjoy your Morgan John
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