Wow, that wasn't easy.
As I found out a week or so ago, after I got off the rest of the left outer longitudinal, I quickly discovered just how poor the condition of the frame was around where the back of the floor pan meets the part where the heater tube enters the longitudinal. The heater tube itself was rusted out in a number of sections, and the frame was thin and perforated in a number of places. The bad news was that all of these little bits needed to be fixed by fabricating patch pieces, and there were lots of angles and curves that needed to be duplicated. I'm more or less complete with the left side now, but it took about 8 hours of work spread out over a couple of days. I started on the part "outside," around where the flexible heater hose connects to the steel heater tube entering the body. I started by removing the trailing arm and torsion bar, all of which I had left in place until this point because they were really causing no trouble. The trailing arm bushings are completely shot, but that was expected and I long ago got replacements for reassembly time. The inside of the torsion bar tube is clean, not rusty, which is a relief, after reading what Tom had to go through to try to clean out his.After the torsion bar disassembly, I removed the largest rusty chunk beneath the torsion bar cover. This exposed the heater tube, which was unfortunately perforated (leaky). The holes weren't too small though, and little patches were not hard to make. I didn't do a great job welding up any of this stuff, but none of the heater tube itself is structural, so if it is ugly, that's OK. There are a few pinholes and stuff left, but again, OK. To do it "right," I would have had to do a _lot_ more cutting just to gain access. I really wanted to replace a large section of the heater tube wholesale, but it was going to be very painful to do. Patching worked.
After fixing this part of the tube, I got a piece of 20 gauge to start fabricating replacement metal for the frame. Lots of trimming, scribing, grinding and the like. I've gotten pretty good at eyeballing these little patch panels. There is no easy way to trace the pattern for them on cardboard or the like, because of limited access from the rear. A lot is done by eye, slowly trimming away the excess. Patience is key. If you get overzealous and cut away too much, you'll have to start over or add another little patch.Welded it in, and finished up with the die grinder with "christmas tree" burr, followed up by angle grinding with the small angle grinder and a roloc disc. I'm quite pleased with the results, what do you think? Compare it to the picture at the top of this entry.
What was left was the section around the heater tube "inside" of the longitudinal. I cut away more of the rear closing panel for access, since I will be replacing this whole panel anyway. The hole in the heater tube here was bigger. Again, elegance wasn't the end result here, but functionality was the aim. I fabricated a patch for the tube, welded it in, and then fabricated another patch to fit around the tube and close up the inner part of the longitudinal. Again, the same trimming routines. None of this was easy, hence the amount of time it took.
"Before" and "After:"
I'm glad it's done, because now there is very little left to do before I fit the left outer longitudinal. Holding that up to the body, there is going to be some significant rework required to make it fit properly at the front and rear, but that was expected.
A complete picture log of the rear frame repair is available here, as a sub-folder of all of the floor pan and longitudinal repair pictures.
In preparation for doing the rest of the left side longitudinal repairs, I spent the morning cutting off the left rocker panel and the rest of the outer longitudinal. The rocker panel is going to be replaced later anyway, and to properly (easily!!!) remove the outer longitudinal, it has to come off. I scribed a cut-line on the rocker panel well below the actual overlapping flange where the rocker meets the fenders, so that there would be room to spare when putting on the replacement.
I cut along the length of the rocker, underneath the door sill area, where the outer longitudinal is sandwiched between the inner longitudinal on the top and the rocker panel on the bottom. For this purpose, the grinding wheel was the only cutting tool I have that was able to get into the close quarters required.After most of the rocker was removed, I started cleaning up the area near the front part, where the horizontal part of the rocker meets up with another piece of sheet metal that it overlaps underneath the door hinges. I also removed the lower portion of the front closing panel, scribing a line right beneath the lowest "rib" in the metal.
I have already ordered full replacement panels for the front closing panels, but fabricating replacement panels if you are only removing this much metal wouldn't be too hard, as you don't need to fabricate any reinforcing ribs in the metal.Finally, I started removing more of the frame area near the left rear closing panel, where the heater tube enters the body. On both sides of the car, there is a lot of rust and perforated metal in this part. Unfortunately. Unfortunately because there are really no repair sections for this part that will work properly, so everything is going to have to be repaired with hand-made patches.
That is where I will begin tomorrow-- more frame repair, and if I finish that, work on properly trimming and fitting the outer longitudinal. If I can get the outer longitudinal on by the end of the month, I figure I'm doing pretty well. That said, I've been pretty bad with my time predictions in the past. Should we say end of April instead of March?I'm still taking a bit of a break from body work. It pays to vary the work to avoid burnout, since the project is taking so long. Next week, back to outer longitudinal replacement.
The Porsche 356 uses a solid shift rod mechanism to actuate the various gears in the transmission, which is located in front of the engine, but well behind the driver. This is contrary to cable shift mechanisms or shift mechanisms where the shift lever directly interfaces with the transmission.
Various bushings are used where the pieces of the shift linkage come together on their journey to the transmission, and after 40 years, they are often worn well beyond their useful tolerances. The result is a wobbly shift lever that is all over the place when you are trying to shift, and if things get really bad, you can't find the proper gears at all.There is a tech article on the 356 Registry web site that explains this process in detail for the 356 C, so I won't bother relating it all over here. Suffice to say, I did it. The only difference I had from the article was I had to remove the guide ring bracket along with the shift rod; a metal ring behind the bracket prevented it from sliding off the rod, and it was held on with a roll pin I had to drive out later on the bench. See my accompanying pictures for detail.
Now the shift linkage is all set, and hopefully when installed, shifting will be solid and precise.
Although I long ago re-painted most of the detachable parts of the car (brake backing plates, engine tin, etc.) there were a few pieces left that I hadn't done. The front brake backing plates, rear bumper brackets, and a few other pieces. The weather finally warmed up and dried out on Friday, and I took advantage by doing some painting. I have been using DupliColor engine enamel on most of these parts (ugh! I hear people who do everything the "right way" exclaiming) and while I'm not sure of the long-term durability, I know that prep-work is more than 50% of the battle. I am very careful to de-grease everything thoroughly after sand-blasting, and then to wipe down with lacquer thinner. We'll see in a year or so how well the paint job holds up.
I also painted the metal seat rails. Originally, I had hoped to re-plate these, but I hadn't done that yet. I didn't send it off with the chrome plating batch because I think the rails were either nickel or zinc plated, and that's not what the other parts were. Anyway, I painted them with metallic paint followed by clear coat. Yup. I'm sure that it won't hold up extremely well, what with the seat sliding on them, but it will work, and they are cleaner than they were before I blasted them. I can plate or powdercoat them at some time in the future.
As far as bodywork goes, I cut away all the rest of the driver's side (left) outer longitudinal, and sprayed on OxySolv rust converter/remover. I'm assessing the plan of attack for replacing the longitudinal. I think I should cut away some of the front and rear closing panels, as well as the rocker panel. I went to Frank to collect my doors, at least temporarily, to make sure I don't twist anything during the rest of the floor and longitudinal replacement. I will install the doors, and then cut off the rocker panel. Despite getting over a lot of my bodywork fears to date, this will be the first piece of "External" or body metal vs. frame metal I have removed, so I've been building up courage to taking the grinding wheel to it.
On a final note, I got into Fuqua School of Business this week, much to my excitement and relief. Classes begin in late August. I hope to get much, if not the rest, of the bodywork done this summer. The house starts getting renovated in about a month as well, so I have a tentative location for working on the 356 in mind for the time we are out of the house.
Anyway, pictures to follow.
I took a break today from bodywork after exposing a bit more of the underside of the tunnel while I nibble away at the old floor pan. As I looked at the heater cable tubes, clutch cable tube, and parking brake tubes, I silently kicked myself for not taping them up inside the tunnel better before the media blasting. I mean, I did follow people's advice, I did tape them...but not very well. That media grit gets everywhere, through the smallest holes. Some grit had gotten in the tubes.
I read on the list or in a book or somewhere that other people faced with similar situations in the past had created really long "q-tip" like devices to scrape out the tubes. This seemed like perhaps the only feasible solution. I decided I would try alternative methods anyway.
First, I tried pumping up an e-brake tube with grease. I mean, they have to be greased anyway, so I thought maybe I could pump grease in through the rear and force old grease plus grit out the front. Well, I pumped a lot of grease in, but eventually there was too much back-pressure and grease just squeezed out of the tube/grease gun junction. With a tighter seal this wouldn't have happened, but even duct tape didn't prove enough after awhile. No grease had come out the front yet. I stopped and thought.
Why not treat the tubes like the barrel of a gun? Visions of a giant spit-ball straw passed through my head. Yup, it would probably work. I got a piece of shop towel, wadded it up into a ball that was tight but not too tight a fit in the tube, and put compressed air behind it. Bam, out it shot from the front of the tube, along with all the old and new grease, and the grit. What a mess! I put some rags in the front of the tubes to catch the glop, and proceeded to do that again with all the tubes.
It has a total success. Tubes are clean, the process was easy, and it didn't take that long. Only bad part is the grease that sprayed around the front of the inside of the tunnel, but since the bottom is off, it won't be too bad to clean up.
Just thought this tip might help others in the future.
Today, after months of thinking about doing it, I got the car on the rotisserie that I borrowed. It wasn't 100 percent smooth, but it wasn't bad either.
The rotisserie I borrowed bolts to both the front and rear fender mounts. This is a fairly sturdy location, but it would probably be better if it bolted to the front torsion bar tube and rear transmission carrier instead. I can't argue with free though, and this is a proven design. It turns out that my welds on the front battery box side panels were pretty damn spot on, the front piece of the rotisserie bolted right up with no trouble. The rear was a slightly larger challenge. Where I have repaired the right rear frame section in the engine compartment, there has been some minor warping of the metal. That should affect alignment, but it might affect bumper placement a tad, we'll have to see. Luckily the bumper has adjustment "slots" to provide wiggle room. The net effect of the warping was that it was a pain in the ass to bolt up the rotisserie bracket, but in the end it did bolt up with a bit of clamping beforehand.
I had the assistance of my friends Gillam, Brad, Alex, and Dave. Thanks to all of them for coming over and doing the heavy lifting. We bolted the brackets on to the bumper mounts first, and then lifted the car up to meet the front and rear rotisserie pieces. First the front, all 5 of us, and then after it was slid home 3 people ran around back to pick up the rear. Once picked up, we let go of the front and helped hold the rear while the last person maneuvered the rear section into place. Not the best way to do it perhaps, if people have suggestions on how to get it on and off more efficiently/safely/easily, please let me know.
We rewarded ourselves for the manual labor with pizza and beer, and called it a night on the car. The rear bolt that secures the car when it is flipped up on its side is stripped out, which I should have checked before but didn't get around to examining until tonight. I'll replace it tomorrow and then get rolling on the inner longitudinal again, this time without having to weld "out of position."
I did most of the driver's side inner longitudinal this morning. It took about 4 hours. Most of the time was spent carefully removing old rusty metal and inspecting the existing condition, and then fabricating the replacement piece. The actual welding and grinding operations only took about an hour. This stage of the metal work is much more fabrication than simple welding!
See the accompanying picture, and more available in the gallery. Next up comes the front section where the floor meets the bulkhead, and the rear section where the floor meets the wall in front of the rear seats. Then the driver's side tunnel section, which is all straight and should be a piece of cake (famous last words). Then we get to do it all over again on the passenger side.
I worked for about 4 hours today on the floor pan perimeter, or more properly, the lower part of the inner longitudinal. This portion of the inner longitudinal forms a flange that the floor pan sits on and is welded to, so it is critical that it is in good condition. If not, even if you have a solid floor pan, it will sag or bow anyway because the thing it is attached to is weak!
I'm working on the driver's side first. The forward portion seems to be the most difficult because there are three regions meeting in this area: The inner longitudinal, the front closing panel of the wheel well, and the frame strut member that goes underneath the front suspension cross member. You have to be careful not to cut away too much rusty metal, because rust or no, it is supporting things, and you don't want the car to sag. I managed to get a new section formed and butt-welded in before moving rearward towards the long side-section of the inner longitudinal (I'll finish the rest of the front later, it is tedious and I need progress to stay motivated...). This section should be easier, as it is all straight. I cut out most of the rest of the driver's side floor pan for access.
Tonight I also looked at Willhoit Restoration's site for pictures of how they have done this repair in the past. There are very detailed pictures of a 64 SC cabriolet that underwent many of the same operations my coupe is experiencing; indeed I think the cab was more rusty! I noticed that when they did the inner longitudinal, they overlapped the repair sections and plug-welded them over the old parts. While not strictly original, this would definitely be faster. Maybe they were working on a budget, because from what I've seen from this shop, they do it all the "right way." Ron Roland described the butt-welding technique, and as I've already started down that path, I'll probably stick with it.
Before I cut any metal, I made sure to review the articles by Ron Roland in the "Nuts and Bolts" column of 356 Registry, spanning volumes 15 and 16. There is extensive review of the floor pan and longitudinal replacement process, with diagrams. If you don't have these volumes of the registry, there is a slightly more concise version of all the articles summarized in the 356 Porsche: Technical and Restoration Guide vol. 1, published by The 356 Registry.
The articles make it clear that you shouldn't attempt to cut out everything at once. Rather, you should cut out the minimum amount of metal necessary to work on a particular section. Even though the remaining metal is rusty or even has holes in it, it contributes to the structural integrity of the car. Especially on open cars like cabriolets or speedsters. Ron heavily suggests leaving the doors on through the entire process to make sure gaps remain correct between the door and the body. I have to go get my doors from Frank to put them back on the body to do this. However, Ron also makes the point that coupes are much harder to bend or twist because of the roof, so I'm not as worried as I would be if this were a convertible.
Before the replacement floor can be welded in, the flanges on all sides of the car body that the floor sits on must be repaired. In my case, some of these flanges are pretty rusty as much as several inches up the side of the car. Especially in the front. Ron anticipates this, and so do the reproduction parts vendors; they supply 90 degree 18-20 gauge angle iron to weld to these sections to form a secure mounting area.Before removing anything, I made careful measurements on the positioning of both the pedal board mounts and the seat mounts, so they can be put in the proper place when the new floor is in. I started by removing what was left of the front driver's side floor panel section. There was already a huge hole, so this wasn't so bad.
I used my air powered reciprocating body saw and cut-off tool, it took only 15-20 minutes. Then, I ground off the primer on the front left inner longitudinal, going as high up the side as I had to in order to find good metal. After this, I drew a line demarcating my cut point, and started removing the lower edge and flange of the inner longitudinal. This revealed the nasty outer longitudinal behind it. No surpises here, I knew this metal was pretty much the worst section of the car before we started any of this. Tomorrow I will continue removing the lower section of the driver's side inner longitudinal, and then maybe even get to replacing it. The replacement metal will be scribed along the cut line, cut to fit, and then butt-welded and ground smooth.In August of 2003, I asked the 356 Talk e-mail group about ideas for what was important to have in a home (or shop) garage where the focus was on car restoration and on-going maintenance. I made a promise to report my findings to the group.
I'm late.
Better late than never however, so here I am. The ideas aren't listed in order of priority, but the ones that seemed most important are included. If you are building your own shop, or retrofitting an existing work space, I suggest you look over this list and consider each idea carefully.