Rear Apron, Boot and Lid
The apron below the boot had been pushed in and pretty beat up before I got the car. I originally filled it with bondo but now it is time for a proper repair. The apron also has some structural integrity as it is the mounting point for the lid hinges. The same incident also cracked the body on both sides in the bottom corners of the boot opening. The boot lid has some minor oil canning in the middle. This repair requires welding and removal of the fuel pump, filter and tank. I knew there was some pretty deep filler in the apron but I did not expect the repair to be a major undertaking. Therefore, I originally intended it to just be part of a chapter. I was wrong. Here it is as a full chapter in itself.
After removing several layers of bondo and some other filler material, I was able
to better diagnose the cause of the damage. There was a fairly clean but deep wrinkle
just below the center of the panel and 80 percent of its length. It was not the result
of a collision. It was, instead, the result of some DPO (dreaded prior owner) thinking
the boot floor might be a good jacking point. This not only bent the floor and cracked
a couple of spot welds but it also buckled the apron which was attached to the floor
along its bottom edge. The dent would not pull out and there was not enough work room
behind it to work it out with hammer and dolly. I eventually had to remove the entire
panel, cut the bottom half off and make a replacement piece.
Removal and making the replacement piece was fairly straight forward but welding it back together was more problematic due to distortion from the heat. Replacing the entire panel would eliminate that problem but the top half has pockets and reinforcement for the boot lid hinges. That would be a major, or nearly impossible, job to reproduce without the original factory dies and presses. These photos give an idea of what I had to deal with. The first one shows the apron after a little of the bondo fell off or was removed. The other two show the damage after all filler and paint was removed. That crease was about 3/4 inch deep. The last photo is the back side of the apron after removal. It shows the reinforcement for the boot lid hinges as well as the serious degradation of the bottom welding flange. This was the point at which I decided to replace the lower portion.
My plan was to tack weld the replacement lower piece to the original upper then finish by brazing the final seam. The problem appeared almost immediately; the compound was racked by the heat to about 20 degrees from end-to-end. I took it apart and tried again, this time with even more clamping and bracing in attempt to control the twisting. This second attempt again failed with the same result. My revised plan was to weld the upper section back in for stability, then weld the bottom to it on the car. I may even resort to brazing if heat still causes excessive problems.
I did repair the rust and distortions in the boot floor with the apron out. Here you
can see the shelf with the apron removed. It is for a jack and tire tools, etc. It
also shows the structural members at either side that brace the apron and hinge
supports to the floor, shelf and body sides. More of these later. I started by removing
as much surface rust as I could. I then began welding cracks and small rust-through holes.
Patching holes in good metal is slow but not too bad. In rust-through holes, however, it
is an entirely different matter; they really want to get larger instead of smaller. Finally,
from about center to a little behind the right support, there was just no way to do it other
than cut out a large section and replace it with new metal. The problem, of course, was
finding good enough old metal to weld the new stuff to. Eventually, the solution was to
braze the new metal to the old. I then applied some all-metal filler over the worst of the
shelf to finish it off. Hind sight is, of course, 20/20. I believe now it would have been
easier to just replace the whole shelf.
That is also the point at which I stopped working on the car for over a year to do the big home remodel job.
. . . Long Pause . . .
For a couple of months after getting free from the remodel project, I experimented with
ways to stick weld the upper part of the apron back onto the car. I have an Eastwood Stitch
Welder device that is supposed to reduce the output from a stick welder by about 1/2, making
it easier to weld thin sheet metal. I burned up a lot of scraps playing with it, thinking I
was getting my welder down to about 20-25 amps. After a time, It was welding all right most
of the time although it was much messier than normal. About then, I noticed that my welder
will go down to 20 amps in DC mode. With that I could eliminate the Stitch Welder. I played
with that several more times with a little better success and it also produced much cleaner
welds. I did get to feeling fairly good about the welds but I never got to the point that I
felt confident enough to actually put it to the test on the car. About that time, my shop
landlord ran out of projects and wanted to start restoring my Sprite. Answering his questions and occasionally helping, took a lot
of time from the Prefect. Also, about that time, my friend, Harold, seeing that I was probably
over my head in trying to weld the apron back on, volunteered to bring his MIG welder down and
weld it for me. Since he had just finished an MGB from what was basically scrap, I knew he could
do it so I finally swallowed my pride and accepted his generous offer.
Harold came and we temporarily installed the top half of the apron and held it in place with the boot lid hinges. He checked it out and informed me that I still had more preparation work before he could reinstall the apron. Some of the structure did not fit right. The sides of the boot, where I had spent some hours removing dents and dimples, did not align with the lid yet. Finally the gap between the lid and apron was too tight. Over the next few days, I corrected these faults. The boot/lid alignment involved a steel bar, a large C-clamp and more that a few words. The tight gap was a result of trying to weld the upper and lower half on the bench so I corrected that with more heat and some pulling, properly directed.
So Harold brought his MIG welder and his expertise and began welding the original top half back
in while carefully maintaining proper alignment. The gaps where I had cut it out were wide enough
that he had to first weld backing strips behind. The corners had torn long before I removed it
and that also forms a channel for weatherstrip all around the boot opening. Those tears also
extended a few inches on either side into the body. Repairing the tears was quite fiddly due to
the shapes involved. After it was in and we were satisfied, he then welded in the lower half. By
welding, I mean a series of tiny dots carefully spaced so as to control the heat in the surround
metal. All together there were several dozen such dots over several passes. The dots form each
pass were ground down before the next pass. This actually took a couple of days to complete.
these photos show the fit before welding and the actually welded left side. That gives an idea
of the number of weld dots and the gap that had to be filled.
Finally, the bottom of that jack shelf is pretty rotten. I should have replaced most of the shelf
but even with the apron removed, access was difficult. I opted to fill rust holes where possible
and patch what was not. The bottom of the apron was originally spot welded to the turned under
edge of the shelf. My solution was to fill the joint with seam sealer then pop rivet the flanges
together. Harold wanted to at least try welding first. Somehow he managed to get that done with
no major burn holes or other flaws. Here is a selfie with us examining or maybe admiring his work.
If you refer back to the shelf photo you will see that the weld seam is actually about 1/2 inch
below the shelf floor.
At this point, I had to temporarily step away from the Prefect to help Dan working on restoring parts for the Sprite. I still need to finish grinding away the welds, reinstall the lid and finish working the metal around the edges. Soon, I hope. We got a lot done on the Sprite but then that also got interrupted for another project. Dan's brother, Dick, has a 1929 Model A Ford that was fully restored several years ago but was in a garage fire in 2008. We all decided to begin restoring it which took a fair amount of time from my projects. The process is described here.
Well, as the rush to get the Model A in primer and protected from rust eased a little, I was able
to devote a little time to the Prefect. I finished grinding the welds on the apron and flattened
it as much as practical. Remember, there is very limited access from the back side and that long
weld seam is a lap joint. A fair amount of filler would still be required, probably more than 1/8
inch but less than 1/4. That's almost nothing compared to what was there before. That considered,
I decided to use an all metal filler for the bulk of the build up. This is a polyester filler but
uses ground up aluminum instead of the softer stuff in typical "bondo". It is not very
pleasant to use. No matter how much I stirred, it was still rather lumpy. Although lumpy, it did
fully set up. It is also stiffer than the usual stuff and hard to stir. I was never able to get it
to lay smooth and sanding is much harder than the non-metal variety as might be expected. The photo
with the silver look is the metal filler. You can see the "lumpyness" of it before any
sanding. The other photo is the first coat of bondo over it in order to get acceptable smoothness.
This was an old can of filler that seemed to be all right but it was dark blue in color, almost
the exact color of my cream hardener. That made it troublesome to mix. I bought a new can and will
switch over to it instead. Meanwhile, tomorrow we get back on the Model A.
Some "down time" on the Model A due to weather less than desirable for painting, I have
been able to spend a little more time on the Prefect. I got the apron finished as much as I want
until the boot lid is finished to ensure they match acceptably. So I started on the lid. There
were some visible cracks, suggesting excessive bondo so I stripped it down and found even more
than I expected. It had to be straightened a lot. This was made more difficult by the double
panel construction. The skin was thoroughly crimped to the structural panel and I was afraid to
risk removing it since replacements are not available. My solution was to remove the inner panel,
one quarter at a time, preserving the structural integrity, to work the dents out of the skin. The
first photo here shows it with the filler removed and some work started in the lower left section.
Notice the upper right quarter is relatively smooth and straight. The lower half was bent inward
about half an inch and was quite rough as can be seen by the paint bits that the D/A sander was
unable to reach. The next photo shows the lower left quarter of the inner panel removed for access
to the back. I will work that section of the skin until acceptable then weld the structure back in
and proceed to the next section until the whole thing is ready for finishing. The right photo shows
interim progress in the lower left after some straightening and shrinking three stretched patches.
The areas near the lower left corner where the smaller dark wrinkles are where the shrinking was
done. It seems the tar painted on the back side interferes with hammer and dolly work and will have
to be removed next. Notice though the difference in the worked panel between these two photos.
I got a little break from the Model A and other stuff and managed to reinstall the lower-left section
of the inner panel, left photo. I welded it in with the torch and all went reasonably well. When I
tried to grind the weld flush, however, I apparently created a problem; I ground the base metal too
thin. So, I had to redo the weld and left it proud. This will be all right since the panel will be
covered with a carpeted panel when all is done. The double welding apparently resulted in a bit too
much heat which then shrunk the structural panel a little near the center. The bottom line is a
slight outward curve at that point so the lid no longer aligns with the surrounding body panel. It
will have to be corrected some way. Anyway, I then removed the right-lower quarter and straightened
it much like the left quarter. Again, notice here the difference between the right photo and the one
above. There are some doticeable dimples in the hinge area on both sides. With the structural elements
involved, it is not practical to work those properly so some filler will be required.
Next I decided to address the alignment between the lid and its surroundings. The induced extra curve in the lid, notwithstanding, closer inspection indicated the curve of the body opening was still not quite right. I again rigged up a stiff angle iron with a couple of welding clamps an a large C-clamp to further coerce it into position. These photos show the setup. It took two or three tries on each side to get the shape just right. Now with just a little filler it will be ready for paint.
With that done, I finally made the decision to remove the upper-left quarter of the boot lid inner
panel to have access to remove the big dent and patch holes for the original tail light and tag
bracket. I carefully cut it out with the saw, leaving plenty of reinforcement around the latch and
bridle rings. The patch shown was probably reinforcement for the light. It seems the DPO had already
brazed the bolt holes closed from the outside but left the hole for the wiring. In fact, further
examination suggests whatever caused the major dent probably destroyed the tail light. Rather than
get a proper replacement, he found some other light that could be adapted then drilled four more
holes to mount it and brazed the original holes closed. At some time later he removed that light
and filled those holes with bondo then just applied a thick layer of filler over the whole thing.
That reinforcing patch on the inside makes it quite difficult to fuller straighten the skin. I tried to remove it but it is either spot welded (I can't find the welds) or brazed so no luck. I was able to remove part (see photos) but the DPO's brazing at the other two holes have not cleaned up enough to do so there. Also, I can't weld the holes closed with the brass there and I can't braze them closed without some backing and can't get to the back on that side, again because of the brass. Below are interim photos of the progress. The left one shows the full lid and the current section relative the the rest, already repaired. The center one is a closeup of the current working area and shows the holes that still need to be filled. It also gives an idea of how much work still is needed to get it as straight and smooth as practical. Compare those to the same area in the photos above to see how much it has been straightened already. The right one is of the inside and shows the problem I have with that reinforcing patch. I also left a lot of material around the latch point as it does not have any reinforcing.
Well, I finally found the spot welds that hold the reinforcing panel on, drilled them and got it removed. Then I attacked the brazed holes by trying to remove all the brass I could with heat and a wire brush. This got it clean enough that I could weld to it and managed to fill the holes. There was enough brass left, however, to contaminate the welds just a little. That resulted in repairing the welding more than once, more hammering and more buildup that had to be removed. I should have just cut that section out and replaced it with new metal. Hindsight usually is 20/20 or at least it is much more likely to be than foresight is. It is good enough that I feel all right in finishing with more of the metal-based filler.
With that done, it was time to reinstall the final cut-out section of the back. I welded it mostly
with the MIG but the seam along the outer edge had too much gap. That one had to be done with the
torch. I tried to go slowly and carefully to minimize heat but failed. I shrunk the back enough to
cause a bow in the frame so that the lid stood proud of the body nearly half an inch at its center.
The only way I could determine to correct the error was to cut the back in order to straighten the
frame then weld it back together with patches to fill the voids. These photos show the required cuts
with tack welds to hold them in position. After each tack, I tested to ensure the fit was good. The
left photo shows the two cuts at the outer edge right down to the skin. The right one is looking
right at the back. The third cut was also required in order to straighten the edge. If you look
closely, you can just see the backing patches I added on the back side of the welds. The screws are
there to temporarily hold them in place while making the tack welds. I will post more after finishing
those welds.
Here are the welds completed and ground down. This was all done with many small MIG dots then ground
fairly smooth. A fairly thin application of the metal reinforced filler and a little sanding would
make it ready for primer. I ran out of the filler doing the apron though so needed some more. The
last I got from the local Pep Boys, a fairly large store, so I expected they would still stock it.
To my surprise, however, the retail store is closed although they are still taking appointments for
new tires. So, I went to Autozone instead and really pleased that I did. I don't want to disparage
a product but the old stuff was very difficult to use and impossible to get smooth, as mentioned
above. I'm pretty sure it was named Metal Fuzion and maybe I just got a bad can of it that time.
Anyway, Autozone had Bondo Metal Reinforced Filler and ultimately it worked, applied and smoothed
just like their regular filler. So I was definitely pleased although it was a little more expensive.
It was still much harder to sand than regular filler as is to be expected. For final finishing, I
applied a coat of regular Bondo over the metal since it sands so much easier. A final sanding with
80 grit made the back side ready for primer. I also got a can of sprayable rubberized undercoating
for the back side of the skin to replace that layer of tar that was there originally. We'll see how
that works out eventually.
Next step was to finish the body work on the skin. As shown in the photos above, it was still fairly rough and the upper left quarter was overworked to the point I had to stop on it and leave it even a little low. Also, the area around the hinges was not accessible so pretty rough. Bottom line, some filler was required but still it is much better than it was. Again, I started with the new metalized Bondo and applied a thin layer over all the rough spots and a couple extra thin layers over the low spots trying to get it at least close to the correct contour. After sanding fairly smooth, I applied 2 coats of the SPI epoxy over the front and back. With that dry, I added a thin coat of regular filler over the entire face to hide any roughness left in the metal filler. These photos are the result.
Next was sand the filler with 80 grit D/A, trying to keep it as smooth as possible until some of
the high spots began to peek through. After that, I put away the D/A and the 80 grit and went to
180 grit on the long board. I tapped some of the bare metal high spots a little with the hammer
then filled low places and sanded again. After that, it was time for a guide coat then sanding
to again locate and repair any flaws. After the second, maybe third, guide coat, I finally decreed
it ready for high-build primer. I still have a couple of small bare spots and I also have a quart
of Rust
Defender that I bought some time ago just to try it out, which I never did. The left photo
here is at that point, ready for high-build. The pink color is regular Bondo and the lighter blue
is poly glazing putty. You can see a couple of bare metal spots too. The right photo is after the
primer had dried.
Well, I apparently bought the Rust Defender longer ago than I remembered. It had separated somewhat
in the unopened can and was really hard to remix. I first thought it was unusable but I finally did
get it done. I mixed a half-pint and started to test and set up the gun only to discover that I
could barely get any paint to spray even with my 2.0 tip primer gun open all the way. My supplier
had written on the can that I could use up to 5% urethane reducer so I did and then turned my
compressor regulator up several pounds. That made it barely acceptable. I had to shoot from about
4 inches and move very slowly to get a wet coat. I think I much prefer the other polyester primer
Slick Sand
that we used on Dick's Model A. Rust Defender does have one advantage;
it can be applied over bare metal whereas Slick Sand cannot. It appears that I did a
fair job of finishing before the high-build as the first guide coat after was all that was needed.
There is one bare metal spot about the size of a nickel and a couple more quite thin spots in the
primer but it is completely smooth now. I followed that with a seal coat of epoxy. The left photo
shows it after sanding and the right is after epoxy. Well, Rust Defender may be good stuff but it
seems they could have found a better color for it.
I started sanding the primer by hand but soon decided that would be a really long-term commitment.
The surface was not as smooth as I would have liked. I thought it laid down fairly wet even though
I had the problems with it. Well, it wasn't too bad and the D/A sander with 80 grit paper made
pretty quick work of knocking it down to pretty smooth. After that, I got the long board with 180
again and took off any remaining texture. With it now smooth, I put on a fairly heavy guide coat
and continued sanding with long board 180 until the guide coat was gone. This is what it looks
like, sanded and installed again. With it installed, I could still see a little misalignment
between it and the boot sides. I had to pull both sides out another 1/8 inch using the same tools
as above. I can't be certain whether I just didn't move it enough initially or it was due to the
induced curve I put in the lid and failed to completely correct. Either way, it is good now. By
pulling the sides outward, the metal had to come from somewhere. In this case, it took the easy
way and just spread away from the lid a tiny bit. You can barely detect that in the closeup photo.
Due to that, I stopped just short of actually flush. The difference will easily repair with just a
thin coat of the metal reinforced filler, including the slight lateral movement, I am pretty sure.
Next I removed the lid and spent a couple of hours or so working the metal on the body around
the lid where it had been damaged. Photos above show it after some work but still not finished.
Here it is, finally ready for filler. I will use the metal reinforced bondo again just for the
extra strength. The filler to make it smooth will be less that 1/16 inch thick but a little
more may be required to make it align properly with the lid. We'll see when we get to that point.
Then there are those holes in the side that I made for the old truck tail lights and intended to
use for the Harley lights I modified. Since I now have a pair of proper Ford tail lights,
see here, I need to fill those holes.