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Ford F-1 Bodywork - Mind The Gap - TechSurface Rust Treatments, Metal Prep, And Bodywork 101 From the December, 2010 issue of Custom Classic Trucks By Ryan Manson
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Anyone who's ever done their share of bodywork in their home garage or shop can attest; it ain't the most fun thing to do. It's dirty, laborious, back-breaking, and for most of us inexperienced body guys, slow going. On the other hand, if the basic skills can be picked up, it's a great way for us po' boys to save a few bucks by doing the work ourselves. And the truth is, there's no medieval magic involved; no secret techniques passed down from generations of Illuminati members. No, it's a handful of simple techniques that any basic bodyworking book can teach you couple with copious amounts of practice. And it doesn't hurt to have a good teacher to at least walk you through the initial steps, but I digress. Recently, my F-1 project that has been slightly relegated to back burner status lately reared its head as it does from time to time and prompted me to get started on the bodywork. It's about 80% assembled and has been waiting on a few sheetmetal mods before being blown apart for paint and body; I've just been putting it off. Excuse after excuse was made and the car gods must have really wanted to stick it to me for not a day after telling my significant other about how I should really wait until winter's over as it's really starting to get cold again and the weather won't permit me to lay body filler and primer, Southern California was hit with the hottest temperatures ever recorded. Yes, while we are putting together what should be the winter issue, complete with all its snowball references, Christmas and the like, it's 113-degrees in Los Angeles. So much for that excuse! So I did what any motivated person would do and I rolled up the shop door and I got to work. Here's the Fast Etch product... Here's the Fast Etch product from Eastwood that we'll be using to remove the surface rust. It's an acid-based rust remover and metal prep which leaves a zinc phosphate coating and is non-flammable, non-corrosive, and non-toxic. None the less, it is still acid-based so you'll want to keep it off your skin, out of your eyes, and definitely don't drink the stuff! Admittedly, most of my hesitation in starting the bodywork stems from my lack of knowledge on the subject. Luckily, I've had the opportunity to spend countless hours in cold paint and body shops over the years as I chronicled Street Rodder magazine's many Road Tour cars. I kept my mouth shut, for the most part, and tried to soak in as much as possible when it came to how the various shops achieved the level of fit and finish that they did. I learned a number of useful techniques and I have included a few in this story that I thought I'd share with y'all. Back when I started the F-1 build, I decided to strip each body panel separately, instead of simply taking the entire truck down to the sandblaster, as I repaired the various damaged areas (lower fender corners, running boards ends, etc). As I made my way around the truck, it slowly went from a multi-colored, acid trip to a baremetal masterpiece. At least that's what I like to think. Anyways, over time as it sat in my shop and worked on various other items on the build, the untreated bare metal panels slowly developed a layer of surface rust. Not a big deal, but it's just enough of a pain in that it's one more step added to the final bodywork labor. That being said, it's necessary to remove the surface rust before moving forward with any of the bodywork. To achieve this end, I called up the tech guys over at Eastwood to see what they offered to remove the light scale and rust that had been growing on my truck. What they recommended was Fast Etch, an acid-based rust remover that could be brushed, sprayed, or even wiped onto the truck's surface with a rag. It uses a one-step process to effectively dissolve rust without harming the surrounding metal and leaves a zinc-phosphate coating on the surface.  The first step in gapping...  The first step in gapping the fenders is to knock down the rust and paint surrounding the two edges. This was achieved by using a 3M rust and scale removal disc and a die grinder.  Next, I hit the surface of...  Next, I hit the surface of the fender with a Scotch Brite pad to remove any loose scale and debris that may have been present.  Next the gap is taped off...  Next the gap is taped off so none of the Fast Etch is allowed to run down between the two panels.  I then wiped the surface with...  I then wiped the surface with a clean rag and a bit of Acetone.  Then it was time to apply...  Then it was time to apply the Fast Etch product, which I did so by applying it to a rag and simply wiping the panel down. Eastwood recommends keeping the entire area to be treated moist for at least 15-20 minutes, which means wiping it down a few times.  Here's the surface after the...  Here's the surface after the first initial treatment. Note that there is still some rust that needs to be treated. I could have applied more Fast Etch or applied the first coat longer and more aggressive, but I didn't want to get in over my head the first time 'round. I made a game plan up a few months back in terms of how I was going to tackle the bodywork, with the first step being gapping the front sheetmetal. I decided that once the front fenders and the upper and lower valence lined up nicely, I could disassemble the sheetmetal, send the cab and doors out to get sandblasted, and move my attention back to the bed and rear fenders. Once the cab returned, I'd knock out the door gaps and body work on that and everything would be ready for paint. Therefore, the first thing I'm going to be doing is gapping the front sheetmetal, starting with the passenger fender to upper valence gap. I've worked the front sheetmetal carefully over the last year or so to get the gaps as close as possible in bare metal so that as little filler as possible will be needed to get everything nice and straight. It's going to be a steep learning curve, but if I can do it, anyone can!  Instead, I simply grabbed...  Instead, I simply grabbed a DA sander, slapped on an 80-grit sanding pad and went to town. I liked this idea as it also gave me peace of mind when it came to removing any lurking Fast Etch from the surface of the fender. Eastwood recommends using their PRE product to neutralize the Fast Etch if the area is not to be sanded down further.  Satisfied with the results,...  Satisfied with the results, I then continued on and treated the rest of the fender. Here you can see the section that I hit with the DA and the area surrounding it that has only been treated using the Fast Etch.  Compare the passenger side...  Compare the passenger side fender in the last photo to the driver's side untreated fender in this photo and you get an idea of how well the Fast Etch works in removing light surface rust. I eventually did away with the wiping technique and started applying Fast Etch using a spray bottle and brush to apply it on a larger surface area. This technique worked great.  Here you can see the gap area...  Here you can see the gap area between the front passenger fender and the upper valence. Note the difference between the area that was treated and the area that was masked off. Masking off the gap worked great to prevent any Fast Etch from running down between the two panels, but we'll need to hit the area with the DA to get it all nice and even.  Here's the same area after...  Here's the same area after a minute or so of DA work.  One spot that can be troublesome...  One spot that can be troublesome when it comes to bodywork is where a weld has been made and ground down but may not be perfectly smooth; i.e. cratered. Here, a hole has been welded up but not very well. While I could go back over it with the TIG welder and fill in the cratered areas, I really don't want to risk shrinking the surrounding sheetmetal any further than it may already have been.  In this case, a simple skim...  In this case, a simple skim coat of plastic filler will be fine. However, it's a good idea to hit the cratered area with a wire wheel to ensure that it's nice and clean beforehand. Any dust, debris, or moisture trapped under body filler will wreak havoc later on down the road and we don't want that!  And here's what we'll be using...  And here's what we'll be using to get the sheetmetal nice and straight; 3M Bondo Professional Gold premium body filler.  Before applying any filler,...  Before applying any filler, you're going to want to liberally wipe down the area using a product like 3M's General Purpose Adhesive Cleaner which will remove any FOBs (foreign objects) as well as oil, grease, sweat, etc. Remember that there are all kinds of oils in and on the human body and any time you touch the panel, you're leaving something behind. Take a nice bare piece of sheetmetal and put a nice sweaty hand print on it and come back in a week or two and you'll see what I mean!  With the surface nice and...  With the surface nice and clean, I mixed up a batch of filler and spread a small coat across the length of the fender gap. Immediately following, I used a small screwdriver to split the filler and create a nice, even gap. Depending on the width gap that's desired, anything from a small blade screwdriver to the plastic spreader itself can be used to "drag the gap."  This is what the area looks...  This is what the area looks like right after the gap has been made. It's not beautiful but remember that most of the filler is going to get knocked off anyhow. One thing to keep in mind is that you don't want to build up the edge of either side using plastic filler as it can and will chip or break away, leaving a big, ugly gash. If more than 1/16-inch or so worth of filler is required, you're best to bust out the hammer and dollies and work the sheetmetal a bit closer.  While the gap area was drying,...  While the gap area was drying, I went ahead and worked the center section of the upper valence panel to give a reference of how high and low spots surface after the area has been block sanded down. In this example, the high spots are the bare metal sections while the unsanded, filler areas constitutes the low spots. This is how the first pass will look and each application of filler and consequential block sanding will get the panel closer and closer to perfection.  On a few occasions, the high...  On a few occasions, the high spots are so much higher than the surrounding area that they need to be knocked down using a hammer and perhaps a dolly. This is important to remember as you don't want to build up an entire panel full of filler just to even out on high section. In this case, less is more when it comes to plastic filler.  With the filler given a good...  With the filler given a good thirty minutes or so to "kick", it was time to block sand the area. I'm using 80-grit paper on a foam block that will conform slightly to the shape of the top of the fender and making sanding strokes that go all the way across the entire surface. Make alternating diagonal strokes as well so you don't make any low spots just running it back and forth on the panel.  To get the gap nice and straight...  To get the gap nice and straight once the panel was sanded, I used an old piece of 80-grit paper folded in half and simply sanded through the length of the gap to get a nice, crisp edge.  Here's the finished area,...  Here's the finished area, gapped and ready to rock.  If you're like me and lack...  If you're like me and lack a bit of bodyworking experience, chances are you're ability to lay down a nice, smooth coat of filler is lacking. Therefore, you may need to go back and fill a couple small pinholes and the like. That is what 3M Glazing and Spot Putty is for. It goes on easy and work great for touching up small areas.  For illustration purposes...  For illustration purposes and to keep the surface from surrendering back over to Mother Nature, I shot a light coat of red oxide primer over the worked area. You can see that the gap area looks pretty good while the center section of the upper valence still needs some attention. When I come back to work the rest of the front sheetmetal and do my final block sanding, all this primer will be removed.
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The Thinker??? - Haul Monitor
Ryan talks about the friendly badgering that goes on around the shop and overcoming obstacles that seemly pop up out of nowhere during a project....
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