If you feel the need to overlap the new metal tonto the old, you can step flange the old metal so when the new metal is placed over it, the surface is pretty close to being flat. Then you leave a bit of a gap between the two top surfaces and fill the gap with the weld. After you grind off the high part of the weld, you are left with a pretty smooth surface. Added filler is pretty hard to determine its depth once you have the first few layers done, unless its grossly out of range. This is especially hard if you do a mass covering on the first layer (cover the entire area with filler and sand it smooth) like some shops do. It looks to me like learning to use a hammer and dolly would be a great benefit to you, you can probably reduce the amount of filler you use by 1/2 if you spend an hour or two tapping the metal closer to being flat, especially in an areas where you have access to the back side. Edges that are mostly filler build up crack and chip very easily, and very quickly. Been there, done that.
My metalwork is far from professional, but I try to get it close enough that no more than 1/16" of bondo is necessary anywhere. Then I don't worry about some of the common filler issues like shrinkage, crazing, or shame.
I once had a restored 26 Studebaker 4 door. So, late one evening after a cruise my good buddy asked to drive it the last mile home. Row home alleyway to get to the garage, and not much light. Ruunk the car caught a clothes line, drivers A pillar. Exposed under the paint, was wrinkled rust and as much as a quarter inch of 'mud'.
I've got an OT Ranger pickup stashed in the woods behind the house. Before it got rolled over in a wreck it looked just like any other one, afterwards it looks about like these pics. Figure it must have been a rust belt vehicle, the places that broke off were on the bed wheel wells. Whoever did the work was an artist. Couldn't tell it from any other one until the roll over stressed the bed and popped it off in places. Too much for me.
I think folks would be surprised at how much BONDO was used to "build" some of the famous "sculpted" customs of the past.
I'd second those that have said that 1/4" is acceptable. If I recall correctly, that is specifically stated on the can of Evercoat Rage Gold. I think that's perfectly acceptable. I know this has been an often-debated issue, whether to go filler direct to metal, or over epoxy prime. My (albeit limited) experience, as well as the training videos I've watched from HOK, have taught me to go filler directly over metal, then prime. Don't forget, that you will need at least 80 grit below the filler to give it some tooth to grab onto. Some icing is also a good idea to help fill pinholes you may have in the filler. You might also consider the use of spray poly for some build to block down. I see some friends of mine who spend a lot of time metal finishing their body work, which is incredibly impressive and well beyond my (and most people's) talent level. But I personally also look at it as unnecessarily overkill. I'm not leaving the car in bare metal, it's going to get painted. And if 1/8"-1/4" of filler and some high build is all the car needs to have a laser straight reflection down the side of it after paint, then IMHO it doesn't matter that the metalwork under it isn't perfect. Get it done and move through the project.
That Nova Scotian home boy does what he does, I say don't slag the Chad man. Bad Chad aside, they can't all be sculpted in Canada. You guys have to realize it happens down south as well. Judging by the pictures posted since, more often then you realize. Judging by the thickness of mud used on some of those sculpted rides, I'm thinking all those fine art degrees found a place in society to earn a living. These by the way are net pics. While I try to do better, I've come to a point in my life where I realize, if it's a choice between not having because I can't afford perfect, or settling for something that resembles perfect, I'm prepared to soften my stance some what.
That's why we spray epoxy primer, with a little reducer in it, over the metal, before we put filler on!
Hammer and dolly the metal as close to the correct shape as it can be, without making to high (cannot fill a high spot). Tack weld, grind, and then adjust with the hammer and dolly for each tack. Cut the tack and do another one if it is wrong. Repeat until you have a full weld, with no gaps or pinholes. Put seam sealer on the back side of the welds. Fiberglass Evercoat (now with Kevlar), is good for spots that are deeper that the regular filler manufacturer expects. It is also waterproof, so it will not convey moisture to your panel. Evercoat Rage Gold will take care of the rest. While you should always strive to do the best you can, perfect metal finishing is only done by a handful of shops, on example cars. All of the rest get filler. People seem to think that these cars are just rolled into the booth, and shot one-and-done. They are not. I just reasonably metal finished a pair of fenders for a Chevy truck. They looked great. Everyone thought they were ready-to-spray. Once I premiered them, dusted on some guide coat, everyone involved quickly learned that they are far from done. I don't metal finish like that, and my customers know to not ask. They are aware that that level of finish is reserved for people that can pay to have cars built that are in the six-figure range, often not starting with a 1. As Jim mentioned, don't use filler to make edges. That only works for vehicles that travel in trailers, and get rolled into shows.
My standard response to perfect metal work has always been: "Do you want it on Friday, or in February?"
@gimpyshotrods ,just a question ,when the epoxy is on and the filler applied over it , when sanding the filler obviously the epoxy will be sanded off on the surrounding area. Do you re apply epoxy to the bare metal.?
I wish I knew where to find the guys that did this work. I want to hire them. I can get the metal 98%, but struggle with the last 2% in filler. That's not my art. And yeah, don't slag the Chad, man. That guy builds what makes him happy. Isn't that what the rest of you are doing, or are you trying to win some sort of retro popularity contest?
Indeed, and why I don't seal panels in a color close to the color of the catalyzed filler that I use.
Of course. Primer, sprayed as sealer (adding reducer helps close pores, and increases moisture resistance, see your can label) goes down first. Filler goes after that. Filler is porous, so you need to re-seal that, if you are not going straight to paint, in the immediate future. After the filler work is done, it is fast-build, and block sanding until you learn to hate it, and then finishing the other half of the car.
I was taught “if you wipe it more than twice, ya didn’t get paid enough” Sanding filler over epoxy requires being disciplined enough to ease up when the epoxy starts to become visible. If there’s a low spot, address it as you work the filler. If there’s a high spot, address that before ya break thru the epoxy. If you’re stacking filler beyond its limit who cares if it has epoxy under it.
Even those "Perfectly metal finished" cars get a skim coat and some high build in the end. I was first told this over 20 years ago from a pal that is a fairly high profile builder.
If you wipe it or you spray it……. it’s filler if it’s being sanded to level a surface, no matter what product was used, it’s a filler
Until you spend countless hours developing your skills in metal panel fabrication and finishing, learning that both sides of the panel to be welded must be spotlessly clean. and everything else that I have spent the last 50 plus years developing my skills to make it as perfect as I want. I also ran my own shop for 30 plus years and learn most people can't afford it. Just do what you can with what you have to work with. Be happy with the results knowing you did the best you could at the time. You will get better with each new project. In time you will also learn to buy better cars to start with. LOL Larry
My Model A is about the rattiest thing that anyone would consider a truck. Why did I buy it? I didn't. I traded a 460/C6/NP205 from A Quigley Van that I also got for free (because I wanted the front axle). It came with a title. I am replacing just about every single body panel with new ones. Could I fix the rusty parts? Sure. Will I? Absolutely not. The whole cab can be had new, or every piece thereof. The message here is: your time has value. You just need to compare that value to what the parts cost. It is one thing if you are retired. If it's giving you a reason to get up in the morning, and keeping you both out of the spouses hair, and off the streets, then go for it. It is a whole other thing if you are working for hundreds of hours perfecting body work, while ignoring your family. I have seen car projects kill marriages, and the got car lost in the divorce. With perfect certainty, if you are faced with the question that answers as quarter panel, or divorce, buy the damned quarter panel. You can make more money. You can even make a new family, but it won't be like the old one. You cannot make more time. Use filler. Get it smooth. Move on, and enjoy the time you saved.
I agree with the 1/4" max advisors. There are other indicators you may be using too much filler. If you apply with a trowel, you may be using too much filler. If you walk into the paint store and they automatically set a gallon on the counter, you may be using too much filler. If you skip the mixing board and squeeze the hardener directly into the can, you may be using too much filler.
Perfection is over rated....hell, this car with it's crappy bodywork wound up on the cover of Hot Rod. It's also fun to drive, and goes fast. There's more to life than perfectly straight panels.
Appling too much does not always mean using too much. If you put 1/2" on and sand it down to an average 0.100", then you are not using too much, you are applying too much! Spreading thin twice saves more product than spreading thick, and releasing the rest into the filter, or the wind.
Multiple layers are more stable than one thick layer. Perfection is relevant to the situation or goal. I’ve caved and paved. I’ve metal finished and primed. Just drive it
50 people = 50 opinions. Do what you can live with. No reason you can’t remove the work done and strive for better. Unless you learn now the next project level isn’t going to be raised much. Accept mediocre or less now may not bode well for the future. If you have an affinity for body work you will strive for better. No affinity for repairing than it will be what it will be.
100%. I've learned this one the hard way. If I can buy my way out of a problem in my build, it's almost always worth it.
I don't take issue with small areas getting towards 1/4" if it won't see flex there and if proper prep is followed. You can't always access behind a panel or have access to a stud gun.