Finishing your weld?

[Mathius]

i'm using .023 wire.ER70s alloy
What about your heat and wire speed?What kinda welder?What alloy wire?

Lincoln 135 something or other. Don't know the alloy offhand. It's either lincoln or hobart wire too, not cheapy stuff. 0.23.

This thing doesn't give a voltage setting, just a,b,c or d heat settings. and 1-10 wire speed. wire is on 5 I think... heat is on b or c. can't recall offhand. Not that that will really help you anyways.

Biggest 110 unit I could find.

Mathius

[RobM]

I dont know why your having trouble grinding the welds.... what kind of disk are you using? You should be able to grind the head off a 3/4 ' grade 8 bolt with one of these wheels with no trouble i cant imagin your welds are that hard.

By the way 80proZ.. looking back I agree with the .023 gap on a patch panel. thas kind of what i was thinking when i was talking about the relaxed seam concept.

[Mathius]

I dont know why your having trouble grinding the welds.... what kind of disk are you using? You should be able to grind the head off a 3/4 ' grade 8 bolt with one of these wheels with no trouble i cant imagin your welds are that hard.

I have ground bolts off with my 4.5" angle grinder, multiple times. I've ground rivets off the frame of my old Ford Ranger I used to own. But for some reason I can't get my welds down flat without major pressure, and it starts to damage the surrounding material. A roloc disc doesn't seem to do crap to finish it off (36 grit).

I have yet to try the three flap discs I bought.

I'll try to remember to look up what alloy wire I'm using tomorrow. I'm trying to decide if I'm going to weld the fender here, or take it to my buddy's.

EDIT: If I weld it here at home, I'll try your suggestion of 0.023 gap. If I take it to my buddies, I'm gonna do it how I always do, (eyeball it) just for consistencies sake to see if its my setup or not.

Also, when I get done with the project I'll have pictures. It's just that I don't have a digitcal camera, so I'm using a disposable, and I have to use up all the pictures before I develop them, so I have to finish the project first.

Mathius

[Mathius]

What alloy wire?

ER70s-6

I started thinking.. could shielding gas effect weld hardness? I don't use the typical 75/20 mix that's recommended for this wire. In school, we ran 100% argon on half the stuff in the class, because they could switch it over to aluminum easily. I started doing the same at home for the same reason.

I wonder if I'd get better results with 75/20 mix?

Mathius

[Ricoch3T]

I use the 75/20 mix and the weld still seems pretty hard to me. I've never gone straight argon tho so I can't really compare. I can knock a normal size bead down pretty quick with the 4" grinder. The ones that take longer are the bigger gaps I've had to fill in some what.

Also to get off topic a little, are you pushing aluminum wire with your lincoln? I read somewhere the push type of welders don't work very well with aluminum

ER70s-6

I started thinking.. could shielding gas effect weld hardness? I don't use the typical 75/20 mix that's recommended for this wire. In school, we ran 100% argon on half the stuff in the class, because they could switch it over to aluminum easily. I started doing the same at home for the same reason.

I wonder if I'd get better results with 75/20 mix?

Mathius

[Mathius]

I use the 75/20 mix and the weld still seems pretty hard to me. I've never gone straight argon tho so I can't really compare. I can knock a normal size bead down pretty quick with the 4" grinder. The ones that take longer are the bigger gaps I've had to fill in some what.

Also to get off topic a little, are you pushing aluminum wire with your lincoln? I read somewhere the push type of welders don't work very well with aluminum

No, they advertise you can use aluminum with this welder, but I can't imagine it would work on anything thick enough for me to care about. The machine advertises it will do up to 1/4" steel with regular wire, and 5/16" steel with flux core.

I'm pretty sceptible about those numbers, being that this is just a 110 unit.

But when I need to run aluminum, I pack up the argon bottle and run over to my buddies and use his big miller 220v with the spool gun.

Once this heat breaks, probably over the weekend, I'll be out there finishing up my inner fender, and I'll try to post some pictures of what I'm dealing with.

It's supposed to hit 93 degrees today, and 90 tommorrow, then rain Wed. and back to the mid 80s.

Mathius

[B Schein]

It takes a long time to learn how to but weld patches with little to no distortion as well as have the appearance that it was never fixed. I can do it if I take my time but it has taken me ten years of working on my own cars as well as worked at a professional hot rod shop. The trick is to tig weld them. When you tig weld the weld is much softer then a mig weld which allows you to hammer the weld. That is the real trick when you are able to hammer the weld any distortion that accurse do the heat and any miss alignment can be worked out. Al so when you tig weld it the weld is much less to grind off. If you have some thing that you are welding and can be planish you can get an almost perfectly seamless weld. You also need to pay attention when you are grinding not to stay on one spot to long or dig the wheel you need to keep the wheel as flat as possible to the panel to avoid grinding one spot to long. You also need to be patient it takes along time to do this don’t expect to weld the whole thing in five minutes and get that type of finish.

[MonzaRacer]

As for welding take about $50 to $75 bucks to local welding shop and some scrape and your welder to a local welding shop and ask for the best MIG welder in the shop to give you an hours tips and practice.
Anyway I have a welder similar just like the mentioned Lincoln.
Mine is an Astro Pneumatic with 2 flip switches,min, max, 1, 2, and variable wire speed.
Best advice I can give is start with slow wire speed and mid heat (as you will find high heat will blow holes easy.
But the way i have is a max ,1, setting and I set my speed on waht would be around 4 on the lincoln if I had to guess, it should sound like a steady buzzing/arc with out pushing the gun or the wire burning up to the tip.
As for straight Argon your getting alot of extra heat in the weld as Argon wont cool aas well as CO2/Argon.
also if you dont ask the company that makes the wire whats best it can weld worse.
As for .023 not welding good or being hard to dress down, your weld should not be very tall if you do it rightabout the same height as the thickness of the metal your welding.
As for using a Roloc to dress down the weld it will do it but takes time AND they have to be on a grinder goint at least 20,000 ropm, they are not low speed gringind discs, a good 4 or 4.5 in angle grinder from Makita, Milwahkee, or even your generic tool supplier will grind down welds then use a Roloc sanding disc to dress it up better.
I also use a straight die grinder with a cutoff wheel attachment tool to grind down welds, its not as pretty .
Now as for air compressors being expensive if your doing this kind of work a $350 4 hp(110v) or 5hp(220v) 15 to 30 gallon compressor will do this work you just have to give it time to catch up if you use samll tank model and this extends dressing time.
Be forwarned if you look at compressors do not believe that a 110 compressor is a 5hp, 110v cannot make a 5hp compressor it a 4 hp, if you look at it the motor will be rated for 110/220 and most likely wired for 110 when you get it.
220v compressors are worth every dollar and they will keep up with even a cutoff wheel (mine is a DeVilbis made Craftsman 5 hp 30 gallon oil lubed) and be very wary of the oil less lager compressors, as they cant run as continuos as an oil lubed one.
also most oil lubed ones will run 20W20 oil(recommended) but I will use 15W40 Shell Rotella T in the winter and straight 30 weight in summer,,, if in the exposed to the current outside temps.
And lots of air flow help them cool so building a small shed for them isnt ok unless it has a big fan to move air through it.
But back to the welding. I used 035 flux core on my floor repair the other day, lots of slag, beads, and such and it liked to burn through the thin areas.
Before I had 023 and 75/25 and welded just about anything I wanted.
If you all had to work where I am now you would quit.
Right now I am in rock driveway , and 2 extension cords and my oldradio, a fan and my welder trying to build a car,,,,in the hot sun, no garage or car port(I may try get one assoonas my ESOP cash comes in).
As for the difference of hardness between mig and tig it depends on the filler, the heat used, the cooling used. I tiged theother day and used simple coat hanger rods,,very sweet and cheap. they last forever.
The fact of the matter I am a novice with tig and the heat control is awesome and you can nearly make a smooth weld.
for mig with any wire I would try to keep my pannel fitment with a single edge razor blade gap all the way around. Klecos and a backup tab to lay your patsh against while tacking is a neat way and you only 1/8 in hole to fill a mig will do it very well if you are a ovie welder put a pop rivet in the hole then weld it up.
If you have air a simple panel flanger will make life easier too as you can flange the area and then lay it in. you dont have to have a flange all the way around just 2 or three tab on floor pans and trunks just hit it with your finish prep. i f its a little warped a little filler goes a long way.
As for me i could care lesswhat the floor panels look like as long as they hold and can be made water tight.
also if your trying to mate thin metal to heavy metal its a dance of welding on the heavy metal and letting the weld grab the thin metal.
As for gas welding I replaced a whole quarter on my 70 Monte Carlo after caving it in with a replacement from another car with a gas torch and bailing wire( yes actual wire they used to bail hay with)AND I welded along the body contour/edge at top of the quarter panel and had it perfect till I thought I needed to pry it out and weld it.
Had a body shop offer me a job hanging parts for them!
My next roll of flux core wire is going to be 030 till I can afford to buy my tank.
Also you can use the "tack and smack" method to align a panel. If the contour is hard get it close, then tack in few places and beat it into submission (alignment) and weld.
Lucky me only has a few small holes to fix and a little mini tubbing to do other than fabbing the rear suspension from scratch.
als ounless your a master welder or have lots of experience miging a cage wont pass most tech inspection from sanctioning bodies. Been ther done that, had to go back overthe welds with TIG to smooth then.
Can it be done? Yes my old boss Paul Mann assembled a Zeeker Crome -Moly tube frame for his Turboed 91 Pontiac Trans Am,,,,and it passed so it can be done, it now runs a 427 sbc w/twin truboes and runs low 4s in 1/8th.
Good luck.