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Bondo! Diy!

7.9K views 47 replies 30 participants last post by  uber95  
#1 ·
I have been waiting for a writup on how to take out the annoying dents in our cars and i have messed around with bondo a few times now and i think i have an idea of how to use it. since all are 240's are primer blak anyway you dont have to worry about painting here. EVERYONE....please add to this b/c i dont know much much i am putting my 2 cents in.

1) to take out little dings and such you take the bondo and that red crap it comes with...put the bondo in a mixing bowl of some sory and put a couple drops of the red stuff in there (the red stuff is what causes the chemical reaction to harden the bondo so you want to mix quick) mix it up very well so there is no air bubbles in the bondo and that it is a pinkish color.

2) take a flat tool (anything you can find around the house) to fill the ding on your car...scrape it flush to the panel...to much bondo will kick your ass in the end b/c you will end up sanding for days.

3) wait a while til it dries...you want it to be hard as a rock before you sand or it wont come out smooth and flush. i have been sanding in circular patterns and that seems to work for me. i use 220 grit to sand it but the more you have to sand off then the more rough sand paper you want. when you get close to sanding it flush to the body of the car you a less rough sanding paper. you dont want to see grit lines in the bondo or body.

4) lastly to make it very smooth i wet sand the spot with a very light grit sand paper and then after it is clean and dry i primer over it and then poof. the ding/ dent is gone!
 
#5 ·
when using bondo, don't apply it over 1/4" thick, it will crack.
you want to use a flexible putty knife, and remember, this stuff is evil, a little bit goes a LONG way. you want to sand down the contact surface first, and hit it with alcohol to clean it too.
don't let water hit it.
prime it as soon as it dries.

that's my basic knowledge, it's really easy to use bondo, but a lot of people don't know how.
 
#6 ·
please people ITS NOT BONDO its called body filler... bondo is a brand name that has made the public think that all bodyman are drywallers..im a bodyman and i hate BONDO anyway if anyone has any ?? about bodyfiller plz pm me and i will be happy to help
 
#9 ·
bondo brand is SHIT and its like comparring 99cent walmart motor oil to mobil 1 syn.BONDO sinks real bad and also pinholes and just flakes off after time i guesss i was trying to say is dont use bondo brand spend a little extra $$ and get a better product it will save you time and money and will make for a better finished product ...and for small dents just use a spot putty not filler.......... much less work
 
#10 ·
dont put too much or too little hardener. I see too many people with gray or dark red body filler. Mix it up all the way so that it is one color.
To tell how much hardener u need, just go across the filler with the hardener in a straight line (Like putting a straight line in the middle of a circle)
 
#12 ·
use the fibersand, that shit is rock hard i've popped it with a hammer and it didnt crack. holds up pretty well to weather too, the bit i did has been sitting out unpainted for almost 3 months and still looks like the day i put it on.
 
#13 ·
u dont sand in circular motions, u sand in criss-cross motions.
 
#16 ·
forgot to add, do not add filler on the car while the car is cold.(filler gets warm when it dry's so it would pop off or it would not stick to the car if the car is cold and the filler is hot.) the filler gets to about 130 degrees so you should apply your filler in warm weather.

if you want to cover up rust holes:
1. prep the area your going to fill.
2. use a pick hammer and hammer down the rust area lightly.
3. use fiberglass filler first, sand(grit to go by... 180, 240, 360) smooth then add your normal filler over that.
4. add more filler if needed to get the panel straight/smooth.
5. after its all straight and smooth, you can start spraying your primer over the sanded area.

ill add some more stuff later.
 
#17 ·
ok..here goes.

Get the better filler, Bondo makes it, but it comes in a goldish can instead of the red kind, much harder and better quality. You can tell in the sanding process.
1. Sand down the area/s to BARE METAL before doing ANYTHING with the filler.
2. wipe clean the are with mineral spirits or any other cleaning agent.
3. mix filler with hardening agent. (its better to put less than you think so you have more time to work with it)
4. Let it dry, don't jump the gun and sand too quickly.
5. Get a block(something to mold to the cars shape) and wrap the sandpaper around it(I use 180grit).
6. Once I get the desired shape, I use 320grit(wetsand)
7. wipe down again with cleaning agent and spray with epoxy primer.
8. fin
 
#19 ·
depends on what filler you used.

if you used fiberglass filler then you dont have to worry, if you used normal filler then you might have to remove it and start over.(normal filler is very porous, it absorbs in moisture) if it hasnt lifted or started to pin hole(you would see holes in the filler like if someone poked it with a needle)then you should be fine.

just move the car somewhere like the garage or something where water wont get into it.
 
#22 ·
When using your standard filler, after it starts to harden but still a little soft, you can use a tool that looks like a chesse grater (hell, I think thats what they call them). It'll take out the lumps and smooth it down faster. After you get most of the excess off, let it harden and sand in a criss-cross fashen. Using the cheese grater tool makes final sanding much faster.
 
#24 ·
wow... i thought just about everybody knew how to use bondo.. now i see i might be wrong.. STICKY!!!