Technical Bodywork pros (Body filler)

Any tips from all you body working pros on the proper mixing and application of body filler ?

I'm always amazed at how easy they can make it look in some of the you tube videos

I sent my RPU body to the blaster and when it comes back I want to skin the whole thing with a coat of filler then proceed to sand the majority of it off.

What amazes me is how the guys who are good at it can mix a big ol puddle of the stuff and then spread it on as smooth as can be ,and fast too before the damned stuff flashes and gets too hard to spread

After they are done the sanding is easier because it was smooth to begin with.... what I do on the other hand is less than smooth and I've discovered a love for 40 grit sandpaper

I have Rage Ultra which is supposed to sand easily.....now if only I could learn to apply it smoothly for less rough sanding initially

Larry

 

Use the correct side of the spreader...yes there is a correct side! Proper 2% ratio of hardener, a nice wide spreader helps..

 

Don't induce air into the mud by mixing too fast, causes air bubbles.
For years I'm still curious after reading about applying filler on bare metal, some say yay, some say nay. What's the current thinking?

 

If it was me I'd cover the freshly blasted metal with epoxy first. That will seal against moisture and other contaminants. From everything I've read, fillers adhere better to epoxy than to bare metal. Bondo is porous.
As for mixing I use a piece of Formica, mixing with a small flexible putty knife in a side to side motion, then scraping the Formica clean and mixing side to side again.
I have a small squirt bottle filled with lacquer thinner which cleans the Formica and putty knife easily. I've used the same piece of Formica over and over.

 

Epoxy primer on bare metal, spread your bondo, take 80 grit and remove some bondo to get general shape before it completely hardens up.

 

I'd recommend a surform (cheese grater) to shape off any high spots.

 

A little bit of honey(bondo thinner) helps to spread and flow better.

 

Temperature is a biggie....when its hot out that stuff will harden so fast you are ....WTF.....main thing is not to thick....I've seen guys sculpt with it though...

 

I've had the same problems on large areas. Pain in the butt. A very good body man advised me that if the area wasn't too wonky to use Slick Sand, a sprayable filler. Two or three coats and you'll have enough to sand down for a good result. However, if it needs some metal work do that first. I also believe in the epoxy coat first.

 

Well whatever you do, don't explain the right side of the spreader thing....

 

Bevelled edge side?

 

Do a search on YouTube for 'Body Filler: Magic Bullet or Easy Way Out' It's a 3 part video and it should explain what your asking.

 

Well that's great
Epoxy primer first, and I haven't even built my spray booth yet.

I've read here that you can fill over freshly blasted metal and then prime....

If I have to primer first it would probably be brushed on

 

Out here in the west media blast shops offer to coat in epoxy at a reasonable price. No chance for contamination. Even fingerprints can ruin a paint job.

 

ah yep...!!!

 

And then when they bring it in LQQKing like this, and say oops it hardened to fast, can you fix this for me...lol---->
.

.

 

Didn't you go with a turbine sprayer? Or am I thinking about someone else?
Won't get much overspray with one.

 

Yes I did but I still want to use a booth sectioned off on one side of my garage.

 

I would always Epoxy Prime a restoration first (PPG DPLF or DPLV). Bare metal flash rusts in 30 min at 50% humidity. Locking down that bare metal is key. You can apply body filler directly over the Epoxy. I'm a huge fan of Evercoat products. They have two fillers that pass 500 hour salt spray tests. Rage Ultra and Quantum 1. Rage Ultra is more of a traditional filler and Quantum 1 is more complicated mixing-wise for a moderate or beginner. They both sand amazing. Spend money on good filler and you'll be glad you did. No need for additives or blends. Keep the air out of it and mix on a clean board like clean sheets or plastic board. Use a firmer spreader. Try go over a more fine scratch. No need to use 36 or 40 grit with these new fillers. Cut the filler with 80 and 180, and finish with 320 all the way out. Your primer surfacer will love you, and you won't have swelling or shrinking down the road!


Sent from my iPhone using The H.A.M.B. mobile app

 

Have your wife spread it for you, if she's ever frosted a cake she'll be able to apply Rage!

 

I'm just an occasional hack, & you've received some great advice. I'll just add that getting the filler/hardener ratio right makes life a lot easier. Since I don't do it regularly, I tend to use too much hardener the first batch or so. Damn, flashed too soon again...

 

What is this Honey bondo thinner you speak about , I never heard of it.

 

Watching that video I'm thinking that I'm in for a treat when it comes to opening my first can of the Rage Ultra.
First of all it looks a lot smoother when mixed than the cheap "Bondo" brand crap that I have used before.

I have my frame prepped for paint and it only took 6 days filling and sanding the frames outer rail faces to cover and refine the outer surface with the 32 style reveal I put in along with the other details.

I'm going out and lay out my booth.....

 

The honey is the actual resin without the dust added as filler. Laying too much on at once is trouble. Mayhap learn metal repair first?

 

1st see if your blaster can shoot epoxy primer on it. That's 1 problem out of the way.

Second, remember everyone is different - but this is probably the best filler I've found that works well with my abilities and the way I think.
USC AG47 - specifically.

I like it better than rage products which are excellent. It's more for light irregularities and final coats.

Mixing is important.
If you're a coffe drinker you know exactly how to add and mix yours.
After years of mixing mud you know exaclty how much. It's directed by weight so without a scale or years of experience you're destined to get it wrong. Get a small ounce scale and get your eye used to it.

Mixing mud is not stirring, it's folding.

 

Perfect. Hung plastic from the ceiling and used a turbine with Epoxy myself. Went easier than I ever thought it would...

 

Hey Larry, It's night and day difference between the cheap stuff. It will powder off like drywall compound when you are sanding it. Make sure you stick to a finer grit sand scratch under the Ultra. It is designed to go over 80 Grit and does not like coarser sanding scratches. Use the chart I gave you for mix ratio and it should give you enough working time. It's better to mix up a little less than you need than waste a bunch by not getting it applied before it kicks. Make sure the body is up to room temperature when applying as well because if the metal is cold and you have the heat on in your garage the outside of the filler will cure faster than what is touching the body and that can lead to issues. Make sure your first pass is very firm to push the filler into the surface this is THE biggest factor for keeping pinholes to a minimum. If you need any help let me know I would be happy to come over and go through it with you sometime.

 

Sounds like watching too much TV, mud the whole car. Not this ni---uh, old bastard. Why? Is it that bad? No hammers or dolly blocks? Just "told" that's the way? I also don't like epoxy under my 'mud' but that's me and my old-fashioned ways. If the car is full of minor waves and such, too numerous to work out or simply not bad enough for hammer work I'd suggest polyester primer over bare metal 1st, seal that with epoxy and then finish prime. Poly primers are like liquid filler and are hardened by a few drops of liquid. You won't pinhole, have varied hardnesses, and all the other foibles that can ruin the enthusiasm of the job in a big hurry. And make no mistake, varied levels of hardner and dry time will net varied levels of hardness. The real hard next to something less and you'll chase a wave between the 2, add more, it gets worse, on n on. You might be surprised how many guys get that fuck up. I can see it from across the room and not even touch the panel, but then I've done this for too long and am too stubborn to put the tools down and walk away. Look into poly primers. Slik Sand is one type, there's others too but Slik Sand is a good one that sands easy, levels nice, pretty solid too. Won't be a "solvent sponge" like heavy filler. Avoid Feather Fill (if they even make it any longer?) It's great if you're into S&M and you're the 'M' Sanding that shit is brutal and it's more pourous than Slik or PPG Shop-Line poly ( I like the PPG). I think at the end of it all it's a great choice. DO NOT USE ETCHING PRIMER UNDER POLY PRIMER. It makes a good parting agent and your poly will peel off like Saran Wrap. Surprised nobody mentioned this yet but there's dozens of ways to the end, this is but 1. Good luck. And wear a mask!

 

Yeah, I was thinking the same thing. I think a filler primer will work much better over large area's that don't have a lot of issues.

 

why would you want to cover the whole car in mud and sand it off? I would go with a high build primer, spray a guide coat then block it out and see where the spots are that need work. then work the metal in those spots. prime-block repeat. then bondo where the low spots are that remain.

I met a couple of clowns who did that to a guys 32 truck cab. bondo everywhere, even where there was no damage, and easily accessible dents bondo'd over. the guy asked me to quickly block it and get it ready for paint, I stripped off everything they did and started over, the cab was blasted when they got it and they bondo'd over rust holes, my favorite part was where one of the door skins was ripped by the hinge, and the guy running the shop "fixed" it by welding the skin to the hinge and warping the shit out of the door.

the guy and his "boys" were a menace to car culture.