Here is a thread that will benefit us all so I hope it will receive alot of responses regarding all aspects, methods and products of body working so we can come to an accurate consensus on what the absolute best body filler to use is in 2009? The last time I did any body work was in 1970 when "Bondo" and fiberglass were the fillers of choice, but I'm sure new, revolutionary products have come along since then.
Has anyone ever used Aluminum Devcon two part Epoxy Putty? It is easy to work, spreads nicely and cures out to a steel hard consistency, but I don't know how it would hold up under vibration, exposure to weather and temperature changes in the metal. What are the pros and cons of lead? Epoxy body fillers? etc.? Thank you. Jim Patrick
My experiance with common bondo type stuff is after about 10 years of use,it is full of bubbles and comeing apart.To thick of a layer will give trouble as well.
Everything I own with bondo in it,rather I put it there or someone else,is bubbleing and giveing trouble.
The amount of work required to do body work right is alot and it is a shame to waste time with stuff that is no good in the long run.I aint fixen stuff for it to last 2 years,I want a life time repair.
The lead I have encountered seems to have held up well.
My experience with lead is that it is dificult to apply and smooth, it is expensive, and it is very heavy.
My experience with bondo is that it is easy to apply, easy to sand with an in-line air sander, and it is light weight and affordable.
That being said, the best method is to work the sheet metal back to its original shape, but I do not have that kind of talent.
Most of the body shops around here use Rage Gold or Rage Extreme body filler,they are strong and fairly easy to sand and it holds up well as in everything else preperation is everything.
Has anybody here used lead-free body solder? I's be interested to know how that is to work with. One of my "someday" ambitions is to learn body work with solder.
I once repaired a large 3" long x 1" wide hole in a Columbia phonograph tone arm (it was involved in a fire) with lead free solder which comes in the form of a 1/8" diameter wire on a roll and is used in sweat fitting copper plumbing fittings. After brushing with flux and gradually building it up above the curved surface of the tone arm using a propane torch, I filed the solder down with a rasp and wet sanded smooth with sand paper (starting with 60 grit and ending up with 600 grit...60,80,100,120, 180,220,400,600) to the curvature of the tone arm, then polished to a mirror-like shine using a buffing wheel and jeweller's rouge. It feathered beautifully and, were it not for the slight difference in color, you could not tell there was a repair. Had I painted it, as you would a fender, it would be impossible to tell there was a repair, so perfect was the border between the solder and the edges of the hole. Could this method be used on an auto body? Jim Patrick
I have used bondo with good success. The trick is not to put it on to thick. I always try to get out as much of the dent or defect in the metal as much as I can then use the plastic filler. There are better brands than bondo but its about the most easy to find and economical. After using the filler I use a high build primer. This usually takes care of the other minor defects and pits. You can sand and prime 2 or 3 times or more using the high build primer and you will be amazed as how good it will turn out. I have a car that it was put on over 15 years ago and its looks fine. If you prime over the bondo that will usually take care of the fading or discoloration for years to come. My amateur opinion.
My older brother used to use 60/40 bar solder and a flux to fill the seams in the older car hoods that were two piece, he would also make a bead or whatever people wanted he used a Presto lite torch and wooden paddles ,and then rasp of different dimensions and finally sanding etc, as Jim says there is no seam and it rarely cracked.its almost a lost art because of the lead problems good products are getting hard to find, go to a gutter supply co for bar solder.
My take is WHY do you even want to use a filler? The trend now is to use less & less filler, --and do more straightening of the sheetmetal first where filler is no longer needed.
Several years ago I held a workshop at my shop demonstrating how to make patch panels from scratch, how to use an English Wheel to work out dents, and how to shrink the sheetmetal to remove the dents. There were a dozen or so Model T guys in attendance. While we have had several of these annual workshops for Model A guys that were very well attended (80-100 folks), we have not had one for the Model T guys since that first one. During the Model T Tour here in Johnson City this past summer, I asked if anyone would like to do it again, and there was quite a few that said they would come.
Maybe it is time for some to think about what projects they could bring and work on. The cost has always been free, ...and folks attending usually just helped defray some of the expenses by buying drinks for the cooler, or several going in together to pay for the Porta-Johns. Outside of that, it is just 2 or 3 days of working on your Model T parts and fellowshipping with others helping them do the same.
Yes I use Devcon aluminum putty for awhile now. I use it to build missle engines. It has about a 25 minute working time when mixed. Also it is very thick. I do not see how you could fill a big gap with it. Once done it would hold though.
After a 1/4 inch of bondo it should be left to dry for at least a couple days and better for a month before any more is added.
I have bondo that has lasted for more than 25 years with no signs of bubbles or cracks.
Brent! It is people like you that make me proud to be part of this organization!!! Here's wishing you and your great family health, wealth and a blessed Christmas!
I agree Brent. While I detested Boyd Coddington's "American Hot Rod" show due to his pendhant for destroying original vintage cars (ie. an original running 1926 Coupe), I did watch one episode where one of his sheet metal workers made an entire fender using an english wheel. He even put a bead around the edge. I have also watched Paul Tuttle Jr. form a motorcycle fender and two halves of a custom gas tank with it, on "Orange County Choppers", so I know how useful one of these tools could be.
I looked at your profile and saw that you have a beautiful 1926 or '27 depot hack, so you know how much more difficult it is to hammer dents out of the gentle curves of the '26 and '27 fenders, as opposed to the flat surfaces of earlier fenders. If I were close to Tennessee, I would surely attend your seminar, but, I'm way down here in Florida, however, if you need a couple of dented 1926 fenders to demonstrate your techniques on, I'll be glad to send them to you as long as you send them back all perfectly smooth and straight. LOL! Jim Patrick
You have some good advice but maybe it isn't directly answering your question. I got some training on body and paint collision repair from Toyota when I was working there in Japan and the point with them is the fillers should only be used about a millimeter thick. Brent is right, hone your skills on panel straightening and fit because for paint, preparation is everything. If its only that thick then the chances of many products failing is much much less.
Brent is correct that everything should be done to repair the metal, but, how many of us have the space and training and money for an english wheel, planishing hammer, shrinker ,stretcher,and the other equipment to do it right, so body filler is the only resource available to most of us. I would love to attend one of your seminars Brent.
Yep, thinner is better. Bubbling is usually caused by poor mixing, excessive amounts of hardener, or moisture getting to it. I was taught to straighten as much as possible, then prime with epoxy primer (not a primer-surfacer!). Apply the "bondo" (bondo is a brand name, but now is used generically for plastic fillers) and shape it. overcoat with epoxy primer--this seals the bondo. Use a spot putty over that , or a surfacer (a spray on high build undercoat)finish sand, and seal coat with epoxy, and apply topcoats.
Don't mix your filler with too much hardener, and try not to work air bubbles into it too.
The bondo sticks better to the epoxy than to bare metal, at least back when I was working with it--now ten years ago!! Materials have changed since then, so your mileage may vary.
Good advice! If the bondo or whatever plastic filler is used it will work fine IF it is applied correctly. Plastic filler has come into use because of time constraints and ease of use in the body shops. Most folks dont have the space or money to tie up in body or metal working equipment. If a body part or fender is in to bad a shape I usually find the best that I can find. I looked forever for a nice or NOS front commercial fender and finally found a nice one at Chicksha. It beat paying over 400.00 for a repo with no brackets. As David said problems usually arise when you try to apply to much filler to fast. Use less hardener and take your time in spreading it. Not to slow as it will harden soon enough.
While getting out the dents to the point of perfection would be the best way to go, not all of us are adept at this so we must use body filler. What I am looking for is the absolute best body filler there is. Since so much work time and effort goes into the proper preparation of the body prior to the application of the filler and then all the work in dressing it down until it is flawless, I would prefer to pay double or even triple for a container of the absolute best filler there is, as opposed to saving a few bucks on the economy filler. Jim Patrick
Your local paint supplier should have lots of info for you. I have used 3M marine vinyl ester fairng compound with success. "Boat bondo". Its more moisture resistant than the regular polyester fillers. If you are filling a deep gouge, try warming the surface with a halogen lamp, or heat lamp. Wipe with alcohol. Place a layer of glass filled bondo in. Let it fully cure, with either gentle heat, or ultraviolet light. Sunlight is ideal in summer, or I guess it depends on where you live. What you want to do, is avoid "post curing" in sunlight later on.polyester filler shrinks, around 3 percent if I recall correctly. This can happen later on, after painting, not very professional.
After the glass filled layer has fully cured, grind the surface of the filler. By grind, I mean sanding with 36 grit. I usually just use a 4 inch grinder with 36 grit fiber disks, its a real go to tool. For fiberglassing, shaping, etc. What you want, is a surface, with lots of gouges, creating more surface area for the fill to bond to.
After this, wipe with alchohol. Gently heat the surface again. Mix up the regular old bondo and apply. The easiest way to ensure that you fill high enough, (remember the shrinkage) is to surround the area you are filling with two layers of masking tape. You fill higher than the surface, as your spreader rides up on the tape, the shrinkage will bring it back so there isn't much sanding. After primer, if you notice any sanding scratches, a glazing putty works great. Generally they are one part, and cure with UV light.
You mileage may vary, but that's my two cents. Most of the polyester fairing compounds are the same. Its all about surface prep, and following the directions.
By alcohol, I mean methyl hydrate. Some people prefer acetone. I hate the smell of acetone, but it shouldn't matter, because you are wearing a respirator right?
Go to your local body shops and ask what they use. You might be surprised at what they use on the high dollar car repairs. They can tell you what is the best fillers are as they work with it on a daily basis
John, I don't know if that is the way to go. Someone in business to make money on time and materials, working for customers they care nothing about, on modern cars that they have no emotional connection to, tend to buy the cheapest material possible that takes the least amount of time to apply. That way they make more money.
I feel that the members on this forum who, like myself, want only the best for their cars, will be more likely to be most qualified to tell me what worked best for them. At least that is my hope. They have never let me down yet. Thanks. Jim Patrick
On small parts, headlight rings, oil lights, etc., I have had very good luck with the steel epoxy type puttys. They are surprisingly easy to sand and are very tough. Never tried them on a fender or anything large yet, but I think I will when the time comes. I don't like the little tubes of the orange spot putty that the big chain stores have, it's way too soft. I am by no stretch of the imagination a body man though. Dave
Interesting discussion. I've often wondered how a person would go about repairing dents on Model T fenders,running boards, etc., being that there is nothing to hide the underside of the fender one would also have to repair the underside.
I would think that when preparing a car for new paint one would want to have the undersides in the same condition as the top sides.
I like Brent's idea of doing as much straightening as possible and using as little putty as possible. In fact, participating in one of Brent's demonstrations would be interesting and worthwhile especially if you are considering doing your body work yourself. Now how difficult is it to get your hands on an English Wheel and are they very expensive?
I always thought that the customer was the most important part of any business. Failure to please the customer means failure of the business.
Maybe I've been misled.
I agree with Jim. Most people only keep a car 6-7 years. So a body shop might think in terms of what will hold up for 6 years. Jim wants a product that is going to last 20 years or more.
Perhaps that is why you can get one estimate for repair for $2K and the guy down the street wants $4K. Who is going to do a better job? Hopefully the guy charging $4K, and hopefully he cares about his staff as well and that is one of the reasons he charges more.
I would recommend you go ask the dealers. They have a vested interest to keep you happy and hope you will come back to them again and again. They want to maintain their reputation much more than a body shop.
In 6 or 7 years you will likely rack up over 100,000 miles on your modern car that will likely be parked outdoors much of the time. In 20 years, you might put 10,000 miles on your antique that you baby. Apples and oranges....
Why wouldn't a body shop want you coming back again and again? What business wouldn't want return customers?
Oh, and us southerners keep our modern cars longer than that - we don't have to worry about salt eating holes.
Brent, I sure wish you would hold another Model T workshop. I for one could sure use the training.
I vote for Rage Gold. I've used it for a few years now. I like that fact that it can be applied either under or over epoxy primer. That makes the timing of sandblasting, rpiming and filling more flexible. The bodyman that recommended it to me said it was expensive. But, in light of the rest of the expenses in a restoration, an extra five bucks for a gallon of body filler seems really small. Especially, since you'd have a hard time using a whole gallon on one Model T.
The Rage Gold product is wonderful to work with as Eric says.
Devcon is great too, I have used it on aluminum honeycomb skinned aircraft flaps to fill dents the size of a marble, sometimes even larger if an engineer will approve it. It withstands tremendous heat and cold for decades without any sign of giving up. Typically we fill a bit shallow and then use Rage Gold and / or lacquer spot putty over the top.
I haven't used any filler for a while but the last I did was called Technifil(sp?). It came from the PPG paint store. It is like Bondo but they said it didn't have talcum powder base, which attracts moisture and causes problems, as you can imagine. I was very happy with it and how it worked. So far, the repair I did using PPG DP90, K36, and Concept Urethane Enamel color has been on the car for about 10 years and it still looks as good as the day I painted it. I'll try my hand at a photo of the car.
Brent has my vote. I have restored many high end cars... Porsche's, MB 300SL's, Facil Vega's, Bentley's, RR's, T Fords! For me the best solution is to work the metal, shrink it, file it, then if necessary a skim coat of filler.
Filler over moisture, dirt and or old lead filler causes failure.
A good grade filler if kept to less than 1/16 inches with a good epoxy primer overcoat seems to last the best.
That's been my experience.
Brent is correct, however, sometimes there is not enough sheet metal. I have one car that had so much rust that it was like a rough stucco wall after it was sandblasted! i smeared filler over the entire surface and sanded until it was smooth than painted. It has lasted over 15 years.
What brand of filler, Norman? Jim Patrick
Training on an English Wheel? Count me in. Sounds like a great class!
Brent, I like the idea of a workshop too, but I'm too far away. Any chance of making a video and selling it? I would be interested in one. Dave
Great idea David. I'd buy one. How 'bout it Brent. Jim
Don't remember. It's been over 15 years!
Guys, NO ONE is too far away to attend. In reality, this is a priority issue. In the past, we have had people from Colorado, Texas, Florida, Minnesota, Maine, and everywhere in between come to attend. Thus, it really boils down to whether this event is a perceived 'value' to you.
Another misconception is the thing about an English Wheel. While it is true that I probably have $30K plus worth of sheetmetal working equipment, it doesn't take all that equipment to do these tasks. For example, --there is nothing an English Wheel can do that a Hammer & Dolly can't do! All an English Wheel is, ...is a 'continuous hammer' with an anvil (or dolly). The real problem is most people do not know the proper procedure for analyzing a dent and/or the proper method for removing that dent. Most restorers do not know what a slapper is, --nor do they know that they can make one from a Model T spring. Attending something like this exposes them to how it is done, ...and then the "wheels start turning" where that person can find items in his own garage to "make due' to fit their immediate restoration needs.
Something else that needs to be understood. IMO, a Workshop is where you are doing 'work' in a 'shop'. A Seminar is where your sit in a chair listening to someone while your butt goes numb!! We don't do Seminars!!! What we do at this Workshop is ask people to bring small projects where they are using their hands, & their heads in an environment where others can assist them. I usually have myself and 4-5 of my employees walking around assisting folks, along with others who are taking a break from their project so the two people 'network" with each other and discuss what needs to happen next. Every little project has its own unique set of problems that must be overcome. With all the experience in the room, two or three can discuss a plan of action based on past experiences. Now herein lies the problem with a video.
A video is a great tool for teaching "theory", but until a person can actually touch, rub, and feel a panel to understand where they need to be working, it does little good in my opinion. Let me take this even further, ...I have hired two individuals that were graduates of McPherson College with a degree in Restoration. Both individuals were on the Dean's list, so they were "book smart" with regard to the task. The problem is they had no hands-on experience other than watching an instructor in a classroom project environment. Since most of these students did not have a project of their own, all they do is pick up a tool and use it for an hour or so to get an understanding of what they just heard, --and then the curriculum causes them to move on to the next topic. That IS NOT what our workshop is about. I joke when I say we don't allow folks to stand around with hands in their pockets. Everyone that attends generally brings a project, --or makes arrangements to assist someone with their project.
To further add value for someone attending, it really doesn't need to be just sheetmetal. In the past Workshops here, not only have we focused on doing sheetmetal repair, but we have simultaneously rebuilt rear end assemblies, installed upholstery, shown how to re-wood a body, straightened wheels, and all kinds of other things too. While my "plate" is generally full during this time, there are many of you that could come and volunteer to assist someone rebuild their rear end or do some of these other things. If you had two or three guys that each brought their axle assembly, I have a lathe & mill that someone could use to make repairs if that was needed. There is also a wood shop here too. Another thought, if someone needed to have their rear end rebuilt and were going to pay to have this done, I'm sure you could see the 'value' of paying for gas, lodging, and parts to do it themselves in this type of setting instead of paying someone else to do it.
Allow me to put this into one final perspective. If someone was uncertain whether this event would be a value to them, lets just suppose someone lived 600 miles away. Generally we hold the Workshop on a Friday, Saturday, and Sunday from 7:00AM until the last one locks the door at night (generally 8-9:30PM). We usually get a hotel rate of about $60 (+/-) per nite. If someone wanted to attend who was on a limited budget, all they need to do is find someone from their area with a "like interest", throw some Model T parts & pieces in the back of their pick-up, and head this way. Since the actual Workshop does not cost anything to attend (not a single penny), all that someone would be out is their fuel & lodging costs. So if someone were to split expenses with their buddy, in reality their out-of-pocket expense could be as cheap as $125-$150 a piece. The hotel has a free hot breakfast every morning, and so if they brought groceries with them, they could have little costs in that area too. If you need to bring along a few extra T parts to sell to offset the trip expenses, that is OK too!
I guess bottom line is this, if you are still reading this now and you think you would be interested in attending, let me know. We'll see if we can't put something together for a weekend next March or April.
This thread started out asking about a quality filler. Currently I use Evercoat..Metal Reinforced Body Filler for Metal Surfaces. This is a resin based-aluminum loaded material. I have had good results and easy to work. I used something similar many years ago called Alumilead. Find at: evercoat.com
I use Evercoat on my projects.
I always try to get the dents out best I can - even roll on a table top e-wheel and use a shrinking disk.
I was advised by the company that sells the evercoat to me to use a grinder and rough up the surface before I put on the bondo. They said grinder marks in lots of different dirrections will allow the bondo to "grip" to the surface. Most bondos fail because they are put on a smooth surface and it can not bite into a smooth surface.
Travis has great advice. That's one of lessons learned while I was taking panel beating courses at local trade school. Another common mistake is applying thick coats of bondo. If you reshape the metal you shouldn't need much over 1/16 inch! Sometime glazing putty and primer surfacers are enough. On panels that have "swiss cheesed" due to rust, I apply a sheet of fiberglass to the inside (non-visisble) and then apply bondo/putty to the other side to fill in the holes. There are all kinds of best practices to avoid the need to glob bondo on any metal repair.
Sometimes you just have no choice but to put it on thick. A good example is a Wills Sainte Claire fuel tank which is exposed so it is visible, has baffles inside it, and can't be replaced.
Yes, I made the mistake of stripping the paint off its exterior and found 10 dents that had been filled with bondo (or other) over 30 years ago. You know what the stripper did to the bondo....
Should have done lots of sanding instead.
Seth, Dents can be pulled...metal work takes time and patience but anyone can do it. The results are worth the effort.
I just don't know, I reckon the wife's Sunday Roast Dinner is about the best body filler to use. Sure causes me to let out the belt a notch or two!
Sorry guys, could not resist :-)
Certainly they can, though certainly not by me. I guess I should have mentioned that the interior of the tank had been recently cleaned and re-lined. When I got it back, it was somewhat scratched up on the outside - no matter since the paint had all kinds of runs in it and my plan was to repaint it anyway.
Incidentally, the "bondo" was just fine after 30+ years - so fine I had no idea it was there until I started stripping paint. OOPS!. Sitting in museums is obviously easy on "bondo".
New bondo should be fine and doable for me.
The owner gets his Wills back and I get warm garage space back. Win - win.
In hammering out dents in a 1926 fender, some pretty deep, does it help or hinder to heat the metal with a propane torch? I know when removing dents from railcar side sheets with a sledge hammer, the steel becomes much more pliable when heated with a rosebud but that is 3/16" steel plate.
If the metal has stretched due to a deep dent, how does one "shrink" the metal so it can be hammered back into shape?
I have seen a big leather anvil (it looks like a big stump of a cut down tree about 18" dia. x 12" high) used to hammer out dents. Seems like a good, hard, yet malleable surface. Has anyone ever seen this and if so, do you know if they are available anywhere? I assume they are made of tightly rolled leather. Jim Patrick
My Auto Body class teacher (and the books and videos used for the class) say that the sheet metal "wants" to go back where it originally was, and if you find the actual spot where it was hit that caused the dent, and start there, you'll be able to remove the dent. The trouble is, sometimes without a lot of experience, you don't know how to tell where that spot is.
Anyway, it is very interesting to learn how to do this body work, and I've even bought my own favorite hammers and dolly.
The shop class uses different brands of filler, but they are all basically the same: a two part sort of epoxy product that uses a small amount of hardener that is mixed in right before the use. I don't even remember the various brands, but they work better than the old "Bondo" brand type filler from the past. I've tried to not use very much filler on my T truck project. Keep it thin!
I would think a stud welder would be a good way to remove the dents from something like that gas tank.It is a gun like thing that you stick a "nail" in it and stick the nail to the metal and pull the switch.Then use a dent puller on the nail and pull the dent.Saves going behind something or in it to get to the back side.
Last filler I used was Rage.seems to work well.
I hope as this thread progresses primer and paint compatiablity is discussed because that is where I have had some trouble.Paint stayed on my f150 for about 2 years fine,then recently has started haveing "Bubbles" come up and disappear.cant be good.
Yes, I agree that the stud welder would be the way to go. But since it had already been relined (which took over three weeks) before I discovered the "bondo", I don't have a stud welder nor know how to use it, "bondo" had been there before and done just fine....
Bondo is done. Bondo brand too since that's what I had. Next time I need some I'll try Rage Gold based on what I've heard here.
Thanks to all and Happy Holidays!
I don't have a stud welder but on dents that I don't have access to the back of (such as due to other structural members in the way) I have had luck using 4d common nails and welding the head to the dented area. Grab them with vice grips and pull. You usually need more than one nail to work the dent out. When done, grind off the nails.
Jim, Watch the heat! Heat will expand the metal that is already stretched. John is right about finding the right spot, then working the metal from the surrounding area back into the "dimple".
My teacher (a 1940's hot rod guy) once likened dent removal to concrete finishing... if you just finished a sidewalk and your kid steps into it... you don't add more concrete, you work the surrounding concrete back into the "dent" Then beat the kid not the concrete!
Pulling dents like Seth's tank can be done without heat using epoxy and a 16d nail (or several nails)then progressively pulling, when repairing tanks It will sometimes help to apply a little air pressure while doing the pulling.
The most common error the first time body man usually makes is hammering the metal against the dolly! The dolly and hammer should NEVER ring!
I also shrink large areas using a "slap stick" which, in my case, is an old vixen file heated and bent to a curve with a handle. The file teeth slightly grip the metal as you slap the stretched area with dolly behind. moving the metal back into shape.
John and Brent. This is very interesting and intriguing. Thanks to your posts, I'm beginning to think that with knowledge, experience and perseverence, it is possible to bring a fender or body part back to it's pre-accident condition without using filler. That is, by far the best way to go if one has the proper tools and a knack for it.
I work full-time and I have many responsibilities where I work, so I am not able to attend distant seminars or workshops. I am, however, pretty handy with tools and pick up techniques easily, so can anyone recommend a video on basic sheet metal working? That is, hammering out dents with a hammer and dolly, the uses for various shaped dollys, stretching steel, working with an english wheel, etc?
Thank you all for your contributions to this thread. I am learning a lot and re-thinking my appraoch to body work! Jim Patrick
My father started doing auto body work in the 1940's. Back then they didn't use bondo or fillers. He taught me how to work out the dent then what he called "pick and file". You run a file across the surface. The file marks will highlight the high spots. You then use the pick side of the hammer to tap up the low spots. Periodically run the file across the work in a different direction to keep track of your progress. With enough patients, you can bring it to the point where you don't need any filler. I used this method on the bell to the horn and worked it to the point where all I needed to do was prime and paint it. I also did the crown on the top of the fenders of my 24 coupe this same way. You have to have a lot of patients to do this.
He also had a slap file - made out of an old file. Then there was the "church key" which was a long bar maybe 3/8" diameter and about 3 feet long. One end was bent into a D shaped handle, the other had a curve to it and was tapered to a rounded point. It was quite useful in getting though a small opening into the area behind a panel to push out the dent. When all else failed, you got out the "microscopic adjuster" (the sledge hammer). Trees also came in handy. He had a Buick Electra that got hit from behind right in the tail light and buckled the rear quarter panel. The quarter extension was removed, an eye ring was bolted through the hole, then a chain was connected and wrapped around a tree. Put the car in gear and give it a few gentle tugs to pull the quarter panel back into shape. Just have to be very careful not to pull to hard!
He also did a lot of shrinking and many times I got called over to help. My job was to hold the torch and the wet rag. Using a torch he would heat an area about the size of a quarter until it turned red. He would then work it with the hammer and dolly, then quench it with a rag soaked in cold water. I don't fully understand how it worked, but it was something like the heat expanded that small area, but since everything around it was cold it essentially couldn't go anywhere so it kind of expanded into itself. Hammering it "locked the metal into place". When he cooled it, that area contracted and pulled the surrounding metal in towards it. The key was knowing where to heat it which is something I never really understood. If you did it wrong, the panel would warp. One of these days I've got to have him give me some more lessons on this stuff. The T is a good car to learn this on as the metal is thick enough to actually work. Not like the soda can metal in modern cars.
Dave, you've probably described the heat shrinking process as well as any one I've heard.
The metal expands into a dimple which when hammered will shrink into itself getting thicker.
When cooled the surrounding metal is pulled into shape.
I have been able to remove small door dings on a hot day with dry ice... same process!
You have described the heat shrinking process correctly.
I have been doing body work (Part Time) since age 16 and am now 70 and am still doing it....much slower now. I have a wrecked 2008 Honda (salvage) project that I am presently re-building for our family. With new cars, the outside body metal is thinner than our old cars. The metal is also harder and more difficult to shape. With the thinner metal, you have very little thickness when using the peck and file method in bringing up low spots. I still shrink strethed areas using the torch, hammer and dolly then cooling with a wet rag.
You must be careful when using a hammer and dolly to avoid stretching the metal when attempting to remove or smooth out dents. The metal must be shaped first before attempting to make things smooth and flat. After shaping, with a flat body file, I determine which areas are high or stretched and then shrink the high areas. After determining the high points, using a soft flame with an oxygen and acetylin torch, I heat a small spot to a dull red and quickly back the metal with a flat dolly and work the metal around the spot towards the center with a body hammer and then quickly cool with the wet rag.
With a large stretched area, I surround the high point with numerous small shrinks slowly moving towards the center until the area is flat. I am constantly using my hand laying flat or a file to determine which areas must be brought up using a pecking hammer and block. I made my pecking block using a 3" long pice of file and brazed a 1" dia. x 1" long round bar stock centered on one side. With the pecking block placed & held over the low spots I carefully pick up the area using a pecking hammer from the back side. The pecking block will leave the file mark so you can determine if you are hitting in the correct spot. "DO NOT" hit the metal hard as you only want to bring the metal up in small dimples which are them smoothed with the body file. You can do wonders working metal but you must be patient and develop the touch. Not every one has the touch to become skilled with working metal.
You must have a good eye and can feel with your hand when the surface is dIstorted including high and low places.
I grew up living near a body and paint shop, learned to weld, apply lead and paint cars early in life. When in High School, I was removing hood trim, door handles and filling in trunk lids. I peeked hoods and did all sorts of body modifications that was popular during the 50's and early 60's.
While in a local store the other day, I picked up a can of Bondo (real Bondo brand lightweight body filler).
On the back of the can I noticed that Bondo is now a division of the 3M company.
I have never bought any 3M product that I wasn't completely pleased with the way it performed and was always happy to pay the premium price that 3M products cost.
So, with 3M being the parent company of Bondo, I have to wonder if it is indeed inferior to all these other non-Bondo body fillers.
I doubt that it is inferior in any way and that any performance problems with it are the result of operator error.
Seth, while I started this thread to try and find the best possible modern day filler, Bondo is what I originally used back in 1970 and it is still holding up.
I think the reason Bondo has gotten a bad name is because it has been improperly mixed and applied by inexperienced shade tree body workers, of which I am one. One problem arises when it is not totally protected from the environment such as, if it is used on a body panel that is pitted or perforated all the way through and the inside of the panel is not sealed properly for whatever reason. Perhaps because it is inaccessible or not visible or the worker does not want to go to the extra effort to prime and paint an area that will not be seen. This oversight allows moisture and air to get to it. It is really important to be sure to gain access to both sides of the Bondo and totally seal it from moisture on both sides with primer and paint, for continued exposure to moisture will cause it to eventually soften, bubble and start to swell. Hopefully, when I re-do the fenders on my '26 coupe, I will undertake to remove all of the dents, completely as suggested by Brent, John, David and others. Something that I was not able to do back in 1970 as a 16 year old kid because of the expense of tools I would have needed and my limited income at the time.
I have been searching videos on the internet under "english wheel" and "auto body repair" and there are endless videos available on YouTube to show the different techniques with which to do this. You can watch as a metal worker makes a complete Model A fender from a flat piece of sheet metal and another metal worker convert a badly dented fender into a perfectly smooth surface as he talks you through the various stages and techniques. The use of the english wheel is very impressive. Jim Patrick
We are on the same page. I agree with you 100%. I would think that ANY lightweight body filler must be sealed to be protected from moisture. I've never had any problem with its performance either.
Merry Christmas to you and yours,
Thank you Seth. You too. Jim Patrick
Just finished the bondo work on the rear panel of the Autowa.
Had to weld in patches in two places, so started with the disc sander with 80 grit and ruffed up all the surfaces. Then used "Bondo Hair" (3M), that is the bondo with fiberglass strands in it, to give the material more strength, esp since its going over the weld joints.
After several skim coats of the Bondo Hair, used the rasp between each coat to level the large surface, the rasp was about 15" in length.
Sanded more with the disc, and then gave the panel a work over of skim coats of "Half Time" brand bondo. This is easy sanding stuff the paint supply clerk said works well. Went on real smooth like butter.....sanded off very good too.
Now covered with a guide coat of gray primer, then some more sanding tomorrow, and check over any spots that need fixing.
Think all is well, just will spray over the whole body EverCoat brand Dura Build primer/surfacer, covering that back panel too, and the weld patches should be hidden for a long time
You have to love angle sanders!
Here is a photo of a gas pump I used 1 gallon of bondo on about two months ago - I sanded off about 3/4 of that. In the end there was no bondo that was thicker then 1/16 of an inch.
I should add, this pump was so very bad that I had to skim the whole thing with bondo even after working the panels with the dolly/hammer and rolling down bumps in my e-wheel and shrinking disc. I think it was hit on three sides by cars over the years. I have about 20 hours of sanding "or more" in this pump.
The best part is - this is the LAST gas pump I will do until my Model T is finished.
I have about 3 months to GO on that 26 roadster!!!