[Cleangreen68]

Ive been slowly working on the body of my 68 Skylark and just recently welded up all of my trim holes left behind after removing it. Im new to welding and was looking for advice on how you guys would treat the backside of the weld when it's NOT accessible with grinders and such. Most of them I can reach and clean, but what should I do with the ones I can't? I can probably get some spray down there but no tools. Should I just leave it, spray it with some epoxy or undercoating? Or will it still corrode if the weld isn't cleaned first?
How would you do it? Thanks

 

[swvalcon]

Where are we talking about on what panels? wHAT AREAS CAN YOU GET TO AND WHAT ONES CAN'T YOU REACH. PICTURES WOULD BE NICE.

 

[Cleangreen68]

Front lower qtrs, between the door and the wheel well. Fenders also, i didn't want to have to remove the hood/fenders to get to the last two closest to the door. But if it's crucial then I will. I can reach the others. No pics at the moment. Can try in a fee days.
I guess im just wondering how important it is to get these cleaned and protected, and what's best. Or if I dont have to worry too much. I want to do it the best I can now and not have to return to it later.

 

[swvalcon]

One of the best products to use is a 3-m[ rust fighter I]its kind of like undercoating but is more oily and dosen't get hard like undercoating. I think it comes with a small tube to spray into hard to reach areas. That you could get a longer one to get farther back if need be.I think your car should have the air vent at the top of the door opening. I've removed those and sprayed down into the 1/4 panels a little tight but do-able.

 

[mike the painter]

what about getting it from inside the car? most of the old style trim has nuts that can be removed from the inside once you take of the interior panels...

 

[Cleangreen68]

Swvalcon, thanks for the info, ill look into that. And yes I do believe it has the accessible vent.

deadbodyman, yes I think they were held on with nuts, they were removed yrs ago before I owned it. im sure I can access them easier removing the seat and rear panel. I just dont think I will be able to get a grinder in there to clean it up. Or does the back of a weld even need to be grinded down? If it's just coated will it still corrode through the weld?
its very low on the qtr probably between the inner wheel well and the qtr skin. Im just worried it will corrode if not grinded clean prior to coating. Like i said im new to this and dont know what is needed or not.
Thx

 

[mike the painter]

If you can get your hand in there just use a wire brush to get the loose stuff off.and shoot some epoxy or that undercaoting (previously mentioned) on it ,it dosent need any grinding ....

 

[MARTINSR]

HOLD ON HERE BUCKO (I like saying BUCKO ) how in the living hell do you plan on welding those holes up in the quarter if you still have the seat and quarter interior trim in the car???? ain: no this needs a REAL scary face smilie.

You NEVER want to weld up a hole if you don't KNOW what is behind it. You NEVER want to weld up a hole unless you can SEE what is behind it! If it's inside of a rocker or tubing or something, no you can't "see" it, but you KNOW what is behind it.

First off welding doesn't only produce heat in the surrounding area, often tiny sparks go flying and can start a fire or burn or damage other materials. Windows for instance, you want to ruin a window, mig weld without it covered and see what happens. It will be RUINED with tiny specks of metal STUCK into the glass, yes, the spark is molten metal. So if it WILL do this, just what is a spark going to do on the back side of some trim panel with vinyl folded over behind cardboard? What about the dirty magazine some kid dropped into the quarter panel thru the window slot back in 68 when he heard his mom coming out to the garage? How will that magazine hold up with a nice red hot spark falling on it?

You MUST remove that seat and inner trim panels, when you do you will see that you likely will be able to get to those welds and clean them up before you spray or brush something on them. You don't need to grind it, but as mentioned a good stiff wire brush should do it. Then brushing some epoxy primer on there nice and sloppy wet as heck so it soaks into the little crevices and you will be ok. If you can't see the back, if they are in the rocker or something the 3M rust fighter is a good way to go. There are others on the market, the stuff is commonly called "cavity wax" Click here for some on eBay. You want to be sure to get one that has some sort of "wand" that you stick into thru a hole or something to reach into places like the rocker.

But for goodness sakes remove the interior pieces! Everyone here who has done this stuff for any length of time has stories, horror stories! I know I do.

Brian

 

[Cleangreen68]

I know it's no laughing matter but I had to EL OH EL at that magazine comment.
If that kid did drop that magazine from 68 down there ill be happy that the weld sparked burned the bush! Literally lol.

Anyways, I appreciate the smack down on proper welding safety. that was a rookie move I pulled. I did have the glass up with a damp towel on it to keep it protected. But im glad i burn my **** to the ground! Thanks again.

 

[mike the painter]

Even us pros run into trouble.
I was welding the bottom of a cowl section that was rotted and I replaced. when I noticed smoke rolling out from inside the car,Something was on fire and really cooking but I could'nt, see anything it had to be inside the cowl so I ran for the water hose and sure enough it was two feet short,a car was parked on it so I had to move that car ,by the time I got the hose to camaro the flames were coming out the cowl vents about a foot high,this thing was really cooking now,it took about a 1/2 hr of drenching it before I got it out...
apparently the vent under the dash was broken and the previous owner stuffed three tee shirts in there to plug it up...they must have been in there for ten years....
Usually I always have an air blower to put out small fires when welding but since then I always make sure the water hose is there and will reach the car if its needed...just in case...a fire extinguisher is best though ,One time I was torching off a rocker from a parts car and caught the undercoating inside the rocker on fire the fire went up the kick panel and caught the wires under the dash on fire I almost ran that time,the water didnt do anything, luckily it was just a parts car going to the crusher and I was just grabbing some last minute stuff..Even the windshield melted on that one...

 

[Chevymon]

You should always be ready for fire when welding, but its far better in more ways than one to make sure it doesn't happen in the first place. Fire extinguishers will put fire out, but their chemical contents are very corrosive, and like the fire DBM had, it is quite often in hard to reach areas for clean up.

There is an alternative extinquisher that is filled with a gas that is very effective on class ABC fires and leaves no residue or harmful effects (except the fire damage), and that is Halon. http://halonmarketing.com/mall/prod01.php

Its always been expensive but now the EPA baned production and you can only use reclaimed halon, so its even more expensive now.

 

[MARTINSR]

I had a piece of a few month old Honda seat that I use to put over the regulator on the gas bottle on my MIG to remind me to protect the damn car! I got it when I was welding on said month old Honda and started the seat on fire, there went the profit on that one! ain:

I had a co-worker burn a $1500 seat on a brand new Toyota, we are talking BRAND new as in never even been to the dealer when we use to do work for Toyota Motor Company. ain:

The best one was one of the first I ever saw. We are talking in 1979 and it was a Ford Fairmont. The bodyman was welding on it and a spark went in thru the hole in the door were the cable runs thru the remote mirror. I was in the booth getting ready to shoot a car and looked over and saw FLAMES inside the car! Like you Mike the hose from the booth (for wetting the floor) was too short and I was spraying it from about 15 feet away after he opened the door. It burnt the carpet, seat and dash, oh yeah, there goes the profit on that one! ain:

Brian

 

[boatbob2]

Flames.........

Heck,i can top those fire stories,i was grinding some MIG welds,happenned to look over at my OXY/Acetlyne bottle the Acetlene bottle was on fire,(at the valve) I had no choice,i pulled my hat off,and smothered those flames.IF that newly filled tank,had went up,they wouldnt have found any part of me.the valve was tight,the threads on the bottle were boogered.one time,a friend had JUST painted a boat with AWLGRIP,and a guy took a zip loc bag,full of acetylene,,filled it with Acetylene,rolled up a paper ,lit it for a fuse,when it went off,it sounded like an artillery round had gone off,causing the rust flakes from the metal buildings roof,to fall into the wet paint.i thought for sure there was going to be a killing that day....

 

[MARTINSR]

Heck,i can top those fire stories,i was grinding some MIG welds,happenned to look over at my OXY/Acetlyne bottle the Acetlene bottle was on fire,(at the valve) I had no choice,i pulled my hat off,and smothered those flames.IF that newly filled tank,had went up,they wouldnt have found any part of me.the valve was tight,the threads on the bottle were boogered.one time,a friend had JUST painted a boat with AWLGRIP,and a guy took a zip loc bag,full of acetylene,,filled it with Acetylene,rolled up a paper ,lit it for a fuse,when it went off,it sounded like an artillery round had gone off,causing the rust flakes from the metal buildings roof,to fall into the wet paint.i thought for sure there was going to be a killing that day....

LOLOLOLOL, oh my god that is funny. Not too funny because something similar happened to me. In my little shop I had no booth and got away with murder. One day I had some car I was painting the hood right at the rear of the shop by the roll up door. One of my fellow shop owners in the building came up and whipped the door with some tire chains to scare me, the hood was COVERED in crap. ain:

The sad part was I was on the phone with some old lady customer and I was screaming at the top of my lungs obscenities that this lady probably hadn't heard in her 87 years. :drunk:

Brian

 

[66GMC]

...
What about the dirty magazine some kid dropped into the quarter panel thru the window slot back in 68 when he heard his mom coming out to the garage?
...

Sounds like this may have been a personal experience of yours, Brian?


(It's OK ... I have a have a few of my own, too!) :embarrass

 

[MARTINSR]

No, LOL, I just have a vivid imagination.

Brian

 

[1971BB427]

A friend showed me a trick that I've used for years to get to those hard to reach places. Take the nozzle and tip off a can of brake cleaner and install it on your favorite can of Rustoleum or whatever paint you want to use to seal the hidden places. Then get in as far as you can and start spraying. It goes on very wet and really shoots a heavy fog, so be prepared, but it gets into places you'd never reach and is easy to direct the spray. I've even used small hose to connect two nozzles end to end to reach really hard deep spots.
When I was painting the undercarriage, floorpans, and frame on my last project I used this method to get into tight areas, then did the rest with my normal spray gun and even a brush on some. Really works great!

 

[Cleangreen68]

man some great stories here. Not that I look fwd to it, but I'm sure ill end up having some stories myself in due time.
Great advice and ideas guys, this helps out alot thanks!