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Today I used some body solder to attempt to fill in the low spots remaining in the passenger-side door dent. Yesterday I did my best to pull out the dent with a slidehammer and then shrink the sheetmetal back semi-close to flush. Here are the pictures of what it looked like afterwards.

My first step was to clean off the dent area to remove the coating left by the Metal Prep I sprayed on and any leftover debris left from the welding and subsequent grinding of welds. I used a 3M Clean and Strip wheel. BTW, those 3M wheels are fantastic for removing paint and cleaning metal without damaging it, but don't by the ones with a plastic shaft because they will break right off if you try to use them in a drill.

Then I wiped the entire area down with acetone to remove any grease.

The first step in applying body solder is to put on the tinning compound, which binds to the steel and also binds to the solder. The solder itself would not adequately bond to bare steel, so the tin is a necessary intermediate step.

I bought a Lead-Free Body Solder kit from the Eastwood Company; that kit included everything I needed such as tinning compound, a brass brush to apply it, the rods of solder, a wooden paddle to shape the solder after it goes on, some paddle lube to prevent the wood from sticking to the solder, and a nice file to shape body repairs. I went with the lead-free solder because, unlike the lead which was used in the old days for body repairs, this solder can be sanded without releasing particles that would be harmful to breath.

I began by stirring up the tinning compound, and then brushing it onto the door. After the surface was coated, I began to heat the tin using a small propane torch I bought at Home Depot. As the tin began to melt, it turned shiny silver and brown impurities moved to the edges. I wiped the hot tin across the surface of the steel with a clean white cotton shop towel. I moved across the surface of the door heating the tin until it liquefied and then wiping it across, until the entire surface was coated in tinning compound. Then I washed down the tinning compound, which apparently is somewhat acidic, using warm water until the rag I was using came up clean. Then I started applying the solder. I used the same propane torch, heating the door and the end of the rod of solder and depositing globs of solder onto the door. Eventually the rod got short enough that it was getting very hot, so I dropped the remaining two inches or so straight into the repair. Then I used the wooden paddle to try to spread the solder out more flat over the low spots in the door. It was a very inexact way to shape the solder. Here is a look at the profile of the solder repair. I worked the solder with the file that came with the kit, which was only marginally useful, so I also used some 80-grit sandpaper to shape the repair. It came into a bit better shape, though far from perfect.

The last thing I did today was to weld-up some holes in the front fenders. I did similar repairs on the body yesterday. The passenger side fender had some collision damage repairs, and many holes remained where the previous bodyman had pulled out the metal before applying filler. I wanted to seal off these holes in order to prevent water from coming through the back side and causing rust problems down the road.
The front fenders were cleaned previously, so I just spot-welded the holes, building up welding wire from the edges of the metal in toward the center of the holes. After welding I used my angle grinder and cut-off wheels to grind the repairs smooth. After that was finished I went back to the body and cleaned up some of the areas I welded yesterday. On the brake master cylinder niche in the engine bay I used a wire cup to clean and remove any welding slag from the metal. Then I did the same on the front apron around he holes I welded up. With the metal clean and the rest of the paint gone the apron is ready for bodywork.

This afternoon I did some amateur metalworking to try to straighten the dent in the passenger side door. The door has clearly been the victim of some kind of collision and when I stripped the paint there was lot of body filler under there.

I plan to do my bodywork in the following steps:

1. Use body hammers, dollies, slide hammers, and other tools to attempt to pull the dented metal back to flush with, or in some cases proud of, the surrounding un-dented metal.
2. Use friction and heat to shrink any metal high spots from my metalworking back to a uniform surface.
3. Fill the majority of remaining voids with lead-free body solder to build up the area, once again slightly proud of the finished surface.
4. Grind and sand the body solder as flush to the surrounding metal as possible.
5. Apply the thin coat of body filler, sand, repeat...as necessary to get a perfectly smooth surface.

My goal is to minimize the use of body filler to a thin coat, maybe 1/16 to 1/32" and to make the repair as strong as possible. Today's body fillers are incredibly strong and bond very well to metal, but I still think the body solder has an advantage in bonding and strength.

Here are head-on and profile pictures of the dented door.

In order to find the boundaries of the dent, i.e. the low spots, I marked over the surface of the door with a black marker. Then I used a flat sanding block to sand the area, so the low spots would remain dark black.

Here is a shot of the low areas out in the sun where it was easier to see.

Where the dent had been repaired by the previous owner there were a couple of holes in the door skin. I used these and my slide-hammer to pull the metal up. When it became clear that the pulling wasn't popping the dent out but just forcing up localized areas, I drilled a few more holes in order to pull in more areas.

I kept pulling, and adding holes to get the whole area up flush or slightly above the surrounding door area. The metal had been stretched when the dent happened, and I stretched it up in the opposite direction. No question this was the ugliest part of the repair process.

Next I brought out my new shrinking disk. I bought this shrinking disk on ebay from Wray Schelin, who runs the Metalmeet forums, which are really great for discussing metalwork projects of all kinds including metal repairs. There are some real artists and craftsmen over there. The disk is steel and 9" in diameter and I paid $35. The edges are bent up so it won't slice your flesh if you get it too close to your body, which is a nice feature. It is mounted to a large grinder, in my case a 7" angle grinder from Harborfreight. The grinder should have at least 6000 rpm in order to work effectively with the shrinking disk.

The shrinking disk is used to build up friction on the surface of the metal, specifically on any and all high points, making the metal very hot in those areas. After the heat is built up, the idea is to quench the metal with water. The heating and quenching process causes the metal to shrink. The shrinking disk is large enough so that if you run it along the surface of the metal it will only heat up the high points so eventually they should shrink down flush to the original metal.

Here is the shrinking disk and a picture of me running it over the door. After running the disk on the surface for 15-20 seconds or so, I quenched the metal by squirting water on it. The metal sizzled and steamed a bit, confirming that the heat was building. I avoided getting the metal too hot, and making it change to red or blue (which is unnecessary), by only running the disk maybe 30 seconds at a time before quenching. Here are the results after the first shrinking. The process took patience. I continued the cycle of shrinking and quenching, shrinking and quenching. 30-seconds on the disk, and then quench. After thirty minutes of this process, here were the results. Then I continued the shrinking and quenching. After fifteen more minutes, I could tell I was making progress. Finally, after sixty minutes of shrinking I could tell the improvements I was getting were diminished. So I put down the shrinking disk and welded up the holes in the door. I used my 4 1/2" angle grinder and some cut-off wheels to grind the welds smooth. Then I cleaned off the whole area and treated it with some Metal Prep. There are certainly some low spots remaining, which I will fill with solder, but in general the low spots are much smaller and less deep. And perhaps more importantly, the metal is no longer stretched inward and won't "oilcan" in and out when you press on it.

This morning I repaired a crack in the driver's side door that had been caused by either the stress of the window pillar pressing outwards or the side-view mirror. In either case there was a crack in the metal that ran across the top of the door about three inches and then down the door another inch or so. I cleaned down to bare metal using a 3m Clean Strip disk prior to any welding. I used a spring clamp to pull the metal together where it had cracked apart and placed one small spot weld at the corner of the crack to tack it back together tight. Then I placed several more spots across the top of the crack. Then I ran spot welds downward and across until the entire crack had been mended. I went slowly and used only very short pulls of the trigger in order to keep the tacks small. Then I used my 4 1/2" angle grinder with stacked cutoff wheels in it to grind the profile of the spot welds flush. When the welds got close I switched from using the edge of the wheels to using the face in order to flatten them very close to the oringal metal. The finished repair was barely noticeable and will require a minimal amount of filler.

This afternoon I spent some time doing some metal repairs on the hood.

The first order of business was to repair the holes that had been made in the upper corners of the hood to accept the hoodpins, which are history. Each side had one large hole for the pin itself and four smaller screw holes to which the circular pin plate was attached. I began by cleaning the metal bare using a metal stripping disk in my drill. First I welded the four smaller screw holes, then the larger center hole. I used .023" solid core wire and Argon/CO2 shielding gas. Then I ground down the welds using a series of three cutoff wheels mounted in my 4 1/2" grinder. On the lip of the hood there had been a considerable amount of body filler used to straighten the front. After removing it the lip was a bit wobbly on the driver's side front, where there had clearly been some collision damage. In fact, the area had been brazed in order to make it more solid. Here is the area before and after I cleaned the metal with an abrasive disk. So I took the liberty of welding the cracked metal, which made it very solid again. I straightened out the weld beads using the cutoff wheels.

This morning I continued with welding sheetmetal repairs in the engine bay.

Before I did that I actually noticed a very small second hole in the driver's side floorboard. Yesterday I welded shut one hole that measured maybe 1/4" in diameter. This second hole was about half as large and located over by the door sill. I welded it shut with just a few short bursts from the MIG. Then I used the Dremmel with the small cutoff wheels to grind off each weld flush to the floorboard. In the engine bay, on the passenger's side of the car, there were several holes where non-original accessories, for example the electrical fuel pump, had been mounted. Since I'm taking the engine bay back to stock configuration, I needed to repair any of these holes. Here are a couple of pictures of the holes toward the front and also two up higher in the engine bay. Prior to any welding I removed any surface dirt and/or rust by cleaning around each hole using a 3M Clean & Strip Disk. Then I welded up the holes using .023" welding wire and Argon/CO2 gas. The lower rails of the engine bay were made of thicker sheetmetal, but on the sides I tried to back up the metal with some solid steel plate in order to diffuse the heat and prevent melting through. Here is the finished result before I started grinding the welds. First I began grinding off the proud welding metal using two cutoff disks mounted into my Dremmel. Then I decided to mount three cutoff wheels in my 4 1/2" angle grinder and use the edge of it to try to further smooth out the welds. This worked very well and provided a much broader footprint for flattening the welded areas to the surrounding sheetmetal.
On the firewall, in the niche where the brake master cylinder resides, there was a crack in the firewall. From what I've heard this is fairly typical and caused by the force of stepping on the brakes; the sheetmetal on the firewall eventually fatigues and can crack. In addition to repairing this I plan to install a firewall brace that has been invented to shore up this mounting point and therefore remove any slop in the brake pedal motion. Before beginning the repair I cleaned the area with a wire brush, on both sides of the firewall. Then I re-aligned the sides of the metal where it had split by tapping on it with a body hammer. Then I welded the two cracked sections back together. And then I ground down the weld flush with the sheetmetal.
When I bought the car it had hoodpins, which are not original to the roadster. My intention has been to remove them. I removed the pins themselves and then I wanted to seal the holes they had been mounted to. I began by trying to raise the metal around the holes, which had been bent downwards to install the pins. I just used a heavy hammer to pound upwards from inside the cabin; no need to be delicate as I plan to fill the dents later. The main reason to try to roughly straighten the metal was to minimize the amount of filler required later. Here are the holes where the hoodpins had been. So I just welded over the holes. Later I plan to fill the indentations so eventually there will be no evidence that the hoodpins had ever been installed.

This afternoon I used my new welder to repair some holes in the body sheetmetal. Welding closed holes is a good place to start to get a feel for welding sheetmetal, because it basically consists of blobbing into and over the hole a lot of welding wire and then cleaning up the mess later with a grinder. If you blow through the sheetmetal, which is easy before you get some experience with setting the voltage and feed-rate to appropriate levels, well then you've just got another hole to patch. Also, fixing small holes in the body doesn't really constitute making structural repairs, so it is okay if the weld penetration isn't great. For sheetmetal I use the thinnest welding wire I can (.023") in order to keep the voltage as low as possible.

So after practicing on a lot of 1/8" steel stock I bought at the hardware store I jumped right in to making repairs in the body. The roadster sheetmetal is very thin, so it is easy to get the weld to hot and melt right through. Trial and error with the voltage set-up allowed me to minimize this. Also, I found it necessary to back up the sheetmetal with a steel plate to effectively thicken the area and allow for better heat dispersion. Finally, I welded in very short bursts, essentially just making a long series of spot welds, which prevented too much heat build-up.

On the driver's side floorboard there was a small rust-through that I cleaned up using an abrasive wheel. To prevent welding over rust, I used rust-converter on the hole and the area around it. To get a clean weld it is imperative that the metal be completely clean and rust-free. I wore my auto-darkening helmet, welding gloves, and protective clothing before welding. By making each tack slightly longer in duration (by holding the trigger down sequentially longer each time) I found that he material I had previously deposited would melt into the new tack, creating one single weld-pool and allowing me to control the shape of the repair better. In the trunk there was a hole by the jack bracket. I used a wire wheel to remove the paint from around the area and did the same on the underside of the body. I started welding up the hole from the bottom, building up tacks from the sheet metal rim around the hole inwards towards the middle of the hole, where tacks from either edge of the whole met. After building up a lot of welding wire I moved to the inside of the trunk and built up some tacks on that side. Then I used my Dremmel with a pair of small cut-off disks mounted in tandem to grind down the welding blobs I had created to smooth out the metal. I quickly realized that the body that I had painstakingly washed so many times was getting covered in grinding dust!

I bought a welder. I've been anticipating needing one for the project for some time. After doing some research I settled on the Millermatic 135. I have zero past experience with welding but have read a lot and done some practicing since I got the welding set up. I had several criteria when picking out a welder:

• I don't have a 220 volt circuit in the garage, so the welder has to be 110 volt.
• I definitely wanted a MIG welder due to its relatively shallow learning curve and the fact that it could handle just about any project a hobbyist like myself may tackle.
• I wanted something with shielding gas rather than having to rely on flux-core wire, because everything I've read says that gas makes for cleaner and (most importantly) easier welding.
• I'd like a machine with a coninously variable, rather than discrete, control for voltage and wire feed speeds because I've been told that feature makes it much easier to find an appropriate setting for thin sheet metal, which is my primary concern at this point.
• Subject to the above wish list, I'd prefer to minimize the cost. I'm perfectly willing to pay for a quality tool, but I prefer not to overpay.

So I settled on the Millermatic 135, which has all of the features I'm looking for. I bought the welder from an ebay seller in Indianapolis named Indiana Oxygen Co. (weldingsuppliesatioc) for $566.77, which included shipping to my door. At the same time I bought a 20 cubic foot gas tank from the same seller for $62.87 and some welding wire (one spool of .023" and one of .030") and two sizes of tips. All in for the welder, tank, and consumables I spent about $660 for the entire set-up. I actually bought these items in January and have been setting up the welder and practicing since then. Lincoln has a similar welder that I'm sure is just as good.

In order to complete the set-up I purchased a welding cart, an auto-darkening welding helmet, some heavy leather welding gloves, and a set of welding pliers from Haborfreight. I also went to Tractor Supply to get some shielding gas. The gas I got was 75% Argon and 25% Carbon Dioxide. I handed in my gas bottle in exchange for one they had on-hand that was already filled.

This afternoon I prepped the body tub's bare sheetmetal to prevent surface rust from forming. I used Metal Prep, which is an acid-etching product that removes surface rust from bare metal and leaves a thin protective coating that inhibits more rust from forming. Regular humidity in the air can cause bare steel to flash-rust, so the coverage afforded by the coating prevents that exposure. I started in the cabin, where I treated all of the bare metal spots on the rear shelf and on the firewall, areas that were exposed when I removed seam sealer. I also treated the entire floorboard area, which was exposed when I removed the tar undercoating. I wore rubber gloves to protect my skin from the acid. I sprayed the Metal Prep on using a regular spray bottle, and then rubbed it into the surface using a scouring pad. Then I sprayed another light coating of Metal Prep and wiped off the excess with shop towels after giving it around a minute or two to work. Drips can be pretty messy, so I am always careful not to use too much. Here are the final results in the cabin. I followed the same procedure in the trunk, and in the engine bay. I also treated the rear panel and both rear fenders. On the picture of the fender you can see some drips that resulted from the Metal Prep gathering in the side-molding channel and then flowing down--that's what I was trying to avoid. And I also did the rear shelf and the front cowl areas.

This afternoon I gave the body another washing in order to remove the seam sealer and rust particles, as well as the solvents used to clean up both.

I started out by sanding all of the areas where paint removed, in order to rough them up so the new paint, when eventually applied, will adhere. I used 120 paper and sanded the rear area of the cabin. I was also careful to sand all up underneath the dash on the firewall. Then I started washing inside the trunk, where I had sanded previously. I sprayed with the house to wet everything down, then sprayed Simple Green on all the surfaces. I used scouring pads to scrub all of the remaining particles of seam sealer that had flown off the wirewheel onto the sides of the trunk as well as any of the solvent I'd used to remove the sealer itself. I also made sure to scrub the recessed areas where the drain plugs are in order to remove any rust neutralizer that may remain on the surface. After the trunk was pretty clean, I gave it several more good rinses with the hose. The Simple Green is an excellent de-greaser and the trunk came clean and dried quickly in the hot Texas sun. Likewise I wet down and sprayed Simple Green throughout the cabin, giving every area a good scrub with the scouring pad. The cabin and the firewall came clean and, after I drained the water, dried quickly. Here is the underside of the firewall after the final (I hope!) washing.

This morning I continued to address the rust inside the cabin and, to a lesser extent, the engine bay. Yesterday I used a wirewheel to mechanically attack the rust. Today I used chemical means.

I bought a chemical rust neutralizer from Halon Marketing called Rust Away. The liquid is blue in color and can be used to soak parts, or applied onto rusty areas to convert rust. It uses tannins to convert iron oxide into iron tannate, which is black. I applied it to the footwells of both sides of the floorboards by laying on paper towels and them pouring the Rust Away on. The paper towels held the solution in contact with the rusty spots I was targeting. The instructions recommend allowing rusty parts to soak for two hours; I allowed for three before removing the still-soaked paper towels from the floorboards. Visually the rust appeared converted. I repeated the process on the passenger side.
Also the cracked firewall in the brake master cylinder pocket had some rust developing inside. I treated that area by laying paper towels on the engine bay side, then tucking the edges of a couple of towels down into the cracked area. Then I soaked the paper towels and allowed the solution to work for several hours before removing the towels.
With all of the seam sealer and other adhesives removed, it will be time for one more washing before I begin the bodywork in earnest.

This afternoon I continued preparing the body for bodywork by starting to address the rust spots inside the cabin.

In the footwells there were several areas where it was clear water had rested on the floorpans and caused rust. Some of this I'd characterize as "surface rust" while some of it was less superficial in its penetration of the metal. On the driver's side the floorpan was still very solid (thankfully). The worst area was around the drain plug but there were several rusty patches. I began by using a coarse wirewheel on my drill to remove the surface of the rusty patches. For the most part much of the rust came off leaving pitted steel, but in some areas there was rust I couldn't get off mechanically. In one area the metal had thinned enough such that my rust removal opened a small hole in the floorpan. I continued underneath the car with a more aggressive abrasive wheel where the rust was accumulated on the outside of the metal. I was able to thoroughly clear the rust away from the area around the hole. And I got the majority of the rust on the underside, leaving just the pitted steel and some rust-colored dust. On the passenger's side there were a similar collection of rust spots, though not as bad as on the driver's side--the rust had not spread to the underside of the body on that side.

This morning I began doing the final preparations before I begin bodywork on the body itself. The first thing I did was to remove the seam sealer from within the engine bay, trunk, and inside the cabin.

I used a variety of tools, beginning with a small wirewheel mounted on my Dremmel. I found that using a utility knife allowed me to cut down both edges of the seam and remove the majority of the sealer. Using these two methods I was able to remove the bulk of the seam sealer from the engine bay. Next I moved back to the trunk, where I began with the lip where the lid rests against the body. I cut away with the knife and used a flathead screwdriver to scrape the seam sealer up away from the body. Then I moved on to the inside of the trunk. In there the seam sealer was a black material unlike the white stuff in the engine bay and outside the trunk. In some areas there were big blobs of sealer. I used the wirewheel on my drill to get most of it. It came off in little, sticky bits that sprayed everywhere--all over the nicely cleaned trunk. After I was finished with the wirewheel most of it was gone, though there remained some knooks and crannies where the round wirewheel could not reach, so I used my utility knife to scrape away at the very corners. I used my shop vacuum to clean up most of the bits of seam sealer and then did the opposite side. One the outside edges of the trunk there was more seam sealer along the lower fenders, where the drain plugs reside. I did my best to remove as much of it as possible mostly using the knife. Then I worked across the lower edge of the rear panel, working across the trunk from left to right. Inside the cabin there was more black seam sealer all along the seams of the firewall, which I removed. And along the fronts of the rear wheel wells (and around them) on the rear shelf there was more of the white seam sealer which I removed. On the floor behind the seats there was more black seam sealer. After removing as much of it as possible using the knife I scrubbed the remainder off using the same solvent I used to remove the tar-based undercoating from underneath the car, called De-Solv-It. I sprayed it on and used a wire brush to scrub away the sealer. I also used a scouring pad with the solvent. After the solvent had done its job I wiped away the residue using a shop towel. Overall I got most of the seam sealer removed, and used the same techniques to remove it throughout the car.

Today I spent some time preparing the body panels that I removed from the tub. This involved mechanically removing any remaining spots of paint as well as any adhesive or other remaining surface rust, then sanding the remaining paint smooth and washing each panel one final time to remove any paint stripper residue. Finally, I stabilized the metal so it will not immediately begin to rust.

I started with the trunk lid. The top was fairly well stripped, but the underside had a full coat of paint as well as some glue residue around the edges of the lid where the trunk seal-gasket had been glued. Originally on the roadsters the rubber trunk gasket was mounted on the lid itself rather than on the body. Here are shots of the top and underside of the trunk lid after stripping:
Here is a close-up of the glue on the lid. I took the lid outside and removed the glue with a wirewheel mounted in my drill. I also hit any rusty spots or other areas where necessary. On the inside of body panels I intend to leave the existing paint and just paint over it. However, I needed to sand the paint to give it some "tooth" as well as remove any remaining junk on the surface of the paint. I hand-sanded using 100-grit paper.

Then I just washed down both side of the panel using the hose, applying some Simple Green and giving a good scrub with a scouring pad. Then I applied more Simple Green and gave the entire panel a final thorough rinse. Here is the cleaned trunk lid. Next I moved on to the driver's side door. The passenger side will have to wait because it has a big dent on it that will require further attention. On the driver's side I used the wirewheel on the outside to remove any remaining small spots of paint. Then I did the same on the inside, removing any rust or adhesive and doing a sanding on the paint. I washed the door completely as with the trunk lid. And I followed the same procedure to clean up the hood. In general stripping a car to bare metal is risky because bare steel is apt to begin rusting immediately upon being exposed to water, or even to any humidity in the air. Invisible surface rust can begin forming and then fester underneath a new paint job, eventually leading to bubbles and even structural damage. To try to prevent this I am treating the bare sheetmetal with a Metal Prep product. This kind of product is an acid-etch that chemically removes rust and leaves a thin protective coating on the metal that temporarily discourages rust. The etch also has the additional benefit of providing some "tooth" to the bare metal which will help paint adhere. I bought a gallon of Metal Prep from Halon Marketing in Pennsylvania for around $28. I apply the stuff from a spray bottom which I clearly labeled (the liquid is green, so I wouldn't want to confuse it with Simple Green) and I always wear gloves and safety glasses when I work with this stuff because it is acid after all! On the truck lid, I first sprayed the surface, then agitated it with a scouring pad to remove any surface rust. When the Metal Prep does interact with rust it can create fumes so I always make sure there is plenty of ventilation when using it. Then I applied another light spray to the surface, and wiped all of the liquid away using a shop towel. I've found less is better provided I cover the metal, because over-applying the metal prep can create runs that need to be removed later. I followed the same procedure on the door and then the hood. Spray and then scour... Then spray again and wipe off the excess. Here are a couple of pictures of the hood after it was treated.
I repeated the process on any bare metal exposed on the inside of the trunk lid, door, and hood.