i recently bought a 37 ford pickup project from oldfart36, right here on the hamb. its already chopped, but it needs finished. the first thing i need to do is grind the welds smooth. I HAVE NEVER DONE BODY WORK! what do i need to know about doing this? and what should i use to grind the welds? all i know, (or think i know), is not to get any area of the sheetmetal too hot, because it will warp. other than that, i have NO idea what the hell i'm doing. I wanna dive in headfirst and do it myself, but i dont wanna screw it up..(i promised oldfart36 i would do it justice and finish it right).... ANY help would be MUCH appreciated. thanks in advance, davey shumard
I would need to see the welds to give you a good answer but the way I normally do it is start with an angle grinder and a stone. Knock the welds down then finish up with a flap disk on the angle grinder. Do not get the stone into the sheet metal it is just to knock the high spots off the welds. Grind it just like you weld it, move around a lot and do not get the metal real hot in any one location. There are a myriad of other ways to do it but that is how it gets done at my place.
the welds are realy tall, so i will probably need to use the stone like you said. are there different grit ratings on flap disks? as far as moving around: i should do a spot how large at any time? maybe, 1 inch or so, then move elsewhere? sorry if i'm asking the same question, i just dont want it to look like something out of a rebel rodz mag. "readers rides" section, when i'm done. maybe more like a rod and kustom...haha.
I use my die grinder with three 1/16 cutoff wheels on it. Just go slow and hit the weld only, you don't want to grind beside the welds, sheetmetal is thin enough!
If you're turning metal blue, you're too hot. If you burn your hand touching it, you're too hot. Just move around a lot and feel it with your bare hand from time to time and you should be okay. You need to be a lot more careful in the middle of sheetmetal than on a door post.
you just stack the 1/16 cutoff wheels one right on the other, and use the outside edge only? keeping the wheel perpendicular to the sheet metal, correct?
The trick is to only grind on the Welds. If you don't, you will go through the good Metal quick. I have used various methods thorugh the Years-if it's a round shape, like you have, I would use either a die grinder with two stacked discs, or a angle grinder with a 36 grit Roloc Disc. the die grinder can get you into trouble if you don't watch it, as it is designed to cut metal-that's why I stck two cutting discs on it, to try and keep it from cutting. After I use an angle grinder I will switch to a 3" 36 grit Roloc. I have used flap discs, and for me, they can just be too large, and grind metal I don't want ground. If it's a flat surfrace, I will use a 5" air angle grinder with a 36 grit 3m green corps disc-it's all about staying on the Weld-
so too hot for my hand = to hot for my sheetmetal. could i use a sponge and a bucket of water to cool the spots i grind after grinding them, or should you let them cool naturally?
let em cool on thier own. you should get 60 grit disks, most folks get the softer grits and that add a ton more heat, more like polishing and not grinding.
If the metal is hot enough when you do that, it might cause it to shrink. Like da Tinman said- let it cool naturally.
what i do is grind it till its about 1/16th or a lil less then ill file the rest till it is flush thats the best way i think but you got to be patiant and carefull fileing it also and like they said up top when grinding move around alot
Like Tin Man said don't cool it with water. Flap discs come in different grits I usually use a medium grit and a fine if afterward. Flap discs are made the way that they are to minimize warping. A lot of the fellas are not going to knock the weld all the way down but I try to get it down to flush with the metal. I wokrd in a a sheet metal shop for a while where everything was done that way and no filler used before paint. I had to learn to grind things that way because anyone who welded there had to learn to grind I think to show them the importance of fit. Never the less I try and take as much weld off as possible. There is no set amout of how long a section that you grind. Just keep moving and don't try and work a single section down flush at once. You will get a feel for it quick. Don't sweat it just take your time and you'll be alright.
Careful of surrounding metal as you can thin it out. Also dont push to hard as with the heat and preasure you can push the area in. I made these rookie mistakes when i first started.
okay, i think i get the grinding with the wheels, but when does the file come into play? and where can I get the proper file for the job?
I always use a 41/2" grinder with a stone then a flap wheel just remember let the grinder do the work don't put any weight behind it that way it won't get too hot and your grinding stones/flapwheels will last a lot longer .
You are going to use a flat body rasp you can buy them from anyplace that sells supplies for body shops. You can even get them flexable these days. Another thing to consider there will be places where the weld is actually below the lever of the sheet metal. Do not gouge it out. Keep your grinder flat and grind with the weld. You're in Kansas right? How far from me are you? Never mind I see you are in Dodge City, that's about 5 hours? Maybe I can come up with a reason to be there for a weekend.
as a native of dodge city, i can tell you that there is NO good reason to be here for a weekend, unless of course you are broke down, waiting on parts for something to get you out of town! 5 hours is pretty close to how far it was to oldfart's place...that is with a trailer, and rain... I can't tell you guys how much i appreciate all the info and shared wisdom that this page has brought me over the last year...i guess the best way is to finish my truck and see everyone at the next hamb drags. i hope so anyway!
Well I guess to grind welds on a chopped Ford would be as good an excuse as any. I was actually stranded in Dodge City for a day once, road tripping and out of gas and cash. I had to get a little creative to raise cash to get the hell out of Dodge. Ah those were the days.
Good info. I have the same thing to do on my 36 Dodge. Previous owner chopped it, but never finished the welds.
You CAN buy a cut-off disc wheel that is 1/4" thick or so. Lasts longer than stacking the thin ones. I have a spare cut-off tool with a thick disc installed, just for grinding weld beads. You can concentrate on doing it better, and will have more control than using a 4 1/2" grinder. Less damage, especially for a beginner! I also like to use the 2" discs on a die grinder. Again, more control over the work. I would do a 2-3" seam and give it a couple light taps with a body hammer. You need to know if the welds have good penetration. If not, you might just leave some of the weld bead as a precaution, and use more filler. Agree with the eye and ear protection, too, a leather apron is not a bad idea, either. Choprods once had a thread where he showed the damage his chest got when a grinding stone exploded on him. Nasty wound! For doing large areas, I prefer a flap disc, 80 grit, on an air grinder. Again, not as powerful as the electric grinder, but easier to control with less damage, if you lose concentration. Work on about a 1 foot section of weld at a time. Light cuts across the top of the weld. DOn't stay in one area too long, and you won't have ANY heat problems at all!
Just saw this thread. Davey, let me start by saying, while the chop went well, our welds were average. I'd work them slowly and fill in where needed. There is lots of good advise in this thread and, I like you, am taking it all in for future referance. Hope things are going well with the truck, look forward to seeing pics soon.
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