both mig and tig will charge your helmet. my miller has a solar charged battery, but the damn thing just went out. i thoughr it would be an easy swap, but miller soldered in the battery in my style helmet. the style of battery was a PAIN to find locally, so the soldering was the easiest part of the fix.

i'll bite on the questions.... how cleanly do welds need to be finished to be considered "good"? i know some guys can make them dissapear and i used to grind and sand until they did, but i always ended up with the paper thin metal. now, if i try to just get them smooth and there are imperfections, they stay to retain the metal thickness.

case in point; i welded up the joints between the trunk filler panel and quarters today. this was a pretty big seam with both pieces radiused/rolling into the joint even though the flanges were tight(hard to explain but some may understand). my normal series of tacks left me with a weld that was proud in the center but just slightly recessed on the outsides since i was concerned about already putting in more heat than normal due to the amount needing filled. once finished about 50% of the weld is clean and finished, but its not as clean as i would like.

what else can be done now? what else could i have done while welding? i dont want a second pass as i know it will clean up with a skim coat of filler. would the pros be concerned at this point? do your welds always finish perfect or is good acceptable? how often can you make a repair invisible?

That's been my issue as well. In the pic I posted, I could make the weld disappear. I just don't want to thin the parent metal. Glaze will easily cover the small depression. Is this considered acceptable practice? In my mind, I would prefer that to aluminum foil in areas. Any comments?

You don't ever want to leave the part or panel structurally unsound. That's form over function, and doesn't belong on an automobile. As soon as my grinder/sander hits parent metal beside the weld, I quit grinding or sanding. If there is some slight low spot/crater from welding, I leave it for filler, weld again to fill the crater, or paint it. It all depends on the location, material, and function.

jp

That's exactly what my opinion is. I am even unwilling in some cases to come back and add more weld to some low spots because I don't want to add more heat. I have been considering using some silicon bronze filler wire to fix these little imperfections. Uses a little less heat and finishes more easily. Although I would never use it for structural work. Thanks for confirming my thoughts John.

I have been watching www.weldingtipsandtricks.com

You can find him on youtube too

There is alot of videos of how to weld different kind of stuff

Guy really knows what hes talking about.

,Juhani

i posted this in my build thread, but figured i would ask here as well....

i picked up my new door shells and am acutally impressed with the rear fit of the drivers side so far (still a lot to go). the gap is really consistent and the profile matches the quarter well. i was prepared to weld an 1/8th" round rod to the edge of the door to assist in working the gap, but found that i only need to take off a little in one area (.030 over about 4"). so, would you prefer to weld a rod the entire length of the door, or just remove some material? doing so will likely split the skin, but i can either mig or tig it back closed and then file to fit.

which would you prefer?

i do have to weld a rod to the bottom. the gap is a little too wide (~.320), although very consistent since its within .015 front to back.

also, what do you guys do to build an edge up to get panels to flow better across the gap (height not width)? would you rather build with a weld bead of tacks, weld a rod or do the work with filler?

So..........this is my first attempt at welding sheetmetal. Hopefully the pro's will provide some constructive criticism that myself and others can learn from.

I'm practicing on 18 ga using a Lincoln 135sp with .023 wire and C25. I suspended the pieces off the table and gapped slightly with the magnets. Tacked extreme left then right, blotted with a damp towel, hammered them down a little, then repeated the procedure the center, then split the gaps 2 tacks at a time.

After a little hammering the piece is relatively flat at this stage. I'm thinking (guessing) :rolleyes: there is too much wire on top and not enough penetration but the heat looks close.

Rookie work bench
http://sieg.smugmug.com/Cars/Welding...20_xzDyD-L.jpg

Top
http://sieg.smugmug.com/Cars/Welding...68_zz5bh-L.jpg

Back
http://sieg.smugmug.com/Cars/Welding...35_nojBw-L.jpg

Input is much appreciated. :cheers:

You need a little more heat, the bead is just setting on the metal. Not enough penetration on the back side. DeWayne

Yep -- lacking a little heat... shorten your stick out... and hold for just a teenie tiny bit longer... for the penetration.

Thanks guys!

So while I was awaiting the pro's comments I tinkered a little more. Looks like same issue, which is common for me, not enough heat. I'll replicate these using more juice.

http://sieg.smugmug.com/Cars/Welding...28_u7K3L-M.jpg

http://sieg.smugmug.com/Cars/Welding...84_4xoYi-M.jpg

http://sieg.smugmug.com/Cars/Welding...94_hZ4vW-M.jpg

http://sieg.smugmug.com/Cars/Welding...62_ScyC2-M.jpg
I'm assuming I want penetration similar to the left end tack?

Out to burn some more metal! :woot:

Looks better,but I'd still add more heat,maybe turn wire feed down a notch and leave slightly bigger gap,try staying longer on trigger

OK, bumped up the amperage and started getting better penetration. Made one pass with the sander and realized I hadn't taken pics yet.
http://sieg.smugmug.com/Cars/Welding...53_ySRBp-L.jpg

http://sieg.smugmug.com/Cars/Welding...27_mFjmL-L.jpg

Sanded down, couple of low spots :(
http://sieg.smugmug.com/Cars/Welding...25_C49QB-L.jpg

Outside corner piece finished out ok......I think?
http://sieg.smugmug.com/Cars/Welding...75_CjDfz-L.jpg

It's a fine and challenging line, I like the it!.......with scrape metal anyway. :D

What do the pro's think?

Not trying to beat you up when I say this...

It's not the outward appearance that makes a test grade weld... it HAS to have penetration... even if it finishes out "fine" on the visible side.

I agree with Elite -- turn the wire down just a skosh more -- heat up a bit more (one amp per .001 thickness of the metal --- so .125" steel (1/8th inch) gets 125 amps.

And he's right -- just stay with the trigger a bit longer...

Isn't this fun?!

Thanks, I take constructive criticism well, it motivates me. :thumbsup:

I've made some darn purdy cold welds too. :yes:

One per thousandth and few more milliseconds on the trigger - Check!

Fun? H*ll yes, I love it!

Thanks again, I really appreciate it. :hail:

Seeing signs of improvement?
http://sieg.smugmug.com/Cars/Welding...07_aeMTK-L.jpg

http://sieg.smugmug.com/Cars/Welding...44_TDYFX-L.jpg

For scale those are 1" wide strips. Gap approx 1/32, heat up, wire down, 1/4" stick out, and little more trigger.

Tack spacing? The new settings enlarged the size of the tack about 15%.

Thanks

Turn the heat down a bit now --- that's too much penetration. Or you're a little long on the trigger --- hard to tell. But it's too much of the dreaded "P".

Thanks, my guess is a little long on the trigger. Now I have a visual idea where the middle ground is. :thumbsup:

once you have your first set of tacks, concentrate on starting your next set at the base of the first. it may help to grind down your first set before you start your second. if you have too much build up on top, it will take more heat to get the pentration that you want.

This works! Ask me how I know! :unibrow:

Thanks guys! I really appreciate the tricks of the trade input. I was experiencing build up when the spacing tightened up using the alternating method. I'll try the sequential mode in my next lesson.

Nit-picking - I wish my little Lincoln 135+ used a numerical scale for amperage vs. the A-B-C-D, it reminds me of dialing a phone number by alphabet. :(

I also need to fab a "water dobber bottle" as the damp towel method makes the procedure even slower. I have a felted wool area rug with 1/2" dia. tufts that may work as a donor. :unibrow:

Compressed air is better. It works faster and does not create rust.

I will say it again and it keeps getting forgotten due to the difficulty of skill, But Learning to TIG weld this stuff is way better. Once you Learn to work with the TIG you will never go back, unless the situation needs it. It is worth the effort.

I don't care who you are, You will never have the results with the MIG you can have with the TIG. Both processes can be done at Home without a problem.

Now you're exploiting my handicaps, Tigless with a small compressor. :D
A baby Thermal Arc 185 tig is definitely on the want list. Though I do like the challenge of making the mig work in this application. When I bought the mig I thought it would suffice, I quickly learned a lot of the "stuff" I envisioned doing was smaller scale and required a tig to deliver satisfactory appearance in my eyes. :( It's still fun improving the skillsets, but funding the recreation gets spendy fast!

Some of the hand-welded titanium tig work produced by Akrapovic on motorcycle exhausts is just pure artwork in my eyes.

Thanks for the input, I can't learn enough. :thumbsup:

Just wanted to also say thank you for all the great information provided in this thread. It's nice to see so much help and advice from the more experienced members on here.

I'm wondering what some of the experts think of learning on thicker stuff and then working up to the thinner stuff as you get familiar with the process. I had an old flat fender Jeep before my Camaro which was just going to be a beater until I had so much fun learning how to weld it turned into a complete reconstuction. In the beginning I had a much easier time with the .120 wall stuff. Once I got to the sheet metal I kind of had some the motor skills down at least.

Maybe a topic for another thread but with the suggestion of moving to TIG, is there any type of machine you guys would suggest for the home user? I've looked at the new inverter TIG's, like the size, cost etc. of those. Would one of them do everything you need on a car project?

Thanks again, and keep the good info coming, please!

Erik - This started out as mig/tig, so I'd say tig discussion is legal. I've been researching tig's for a while now, what I perceive to be one of the nicer "hobbiest" tig machines is the Thermal Arc 185 kit. http://www.thermadyne.com/thermalarc...dID=10-3073A-2

A comparable Miller would be my next choice.

I too cannot say enough about the knowledge I've gained thanks to the generosity, patience, and understanding of some of the many very talented Lat-G members. I'm forever grateful to the many willing to share their talents and help me learn. :thumbsup:

I have the Miller Diversion 165 and LOVE it for project use!!! :thumbsup:

Now they have the 180 out too which comes with a foot pedal so I would go that route. Anyway, that little 165 has never missed a beat and I have used it pretty hard for extended periods of time. I think Miller has under rated teh duty cycle rating but I can understand why. I do have to say though, after running a Miller Sync250 I do find myself wanting more power from time to time but for the most part we are talking projects that are slightly out of the "norm" for a car project.

Chris

Well, here we go. Just did this tonight. This was all using the TIG machine. Now take this for what it is worth, I have only burned about 6 filler rods with this thing. Oh, sorry for so many pics, I wanted to show every step. I am putting Bear Claw latches in the truck. This is just an example of filling one bolt hole, but illustrates the process ok I think.

http://i140.photobucket.com/albums/r...n/IMG_4882.jpg

http://i140.photobucket.com/albums/r...n/IMG_4884.jpg

http://i140.photobucket.com/albums/r...n/IMG_4885.jpg

http://i140.photobucket.com/albums/r...n/IMG_4886.jpg

http://i140.photobucket.com/albums/r...n/IMG_4888.jpg

http://i140.photobucket.com/albums/r...n/IMG_4889.jpg

http://i140.photobucket.com/albums/r...n/IMG_4890.jpg

http://i140.photobucket.com/albums/r...n/IMG_4891.jpg

http://i140.photobucket.com/albums/r...n/IMG_4896.jpg

This is the back side of that hole inside the door.

http://i140.photobucket.com/albums/r...n/IMG_4895.jpg

So let me have it, what looks right and what looks wrong? I have a lot of welding to do! Thanks for any input.

Oh........ I think we have a new member of "TIGS R US".... :woot:

Once you go TIG you find it harder and harder to pick up the squeeze machine.
:D

Remember -- ALL welding... rule #1 if at all possible.... CLEAN CLEAN CLEAN metal... and even cleaner for TIG. MIG lets you get away with murder... TIG will kick your butt on dirty stuff.

Chad, your's looks like a real project! :D I can sure see the benefits of TIG in this situation, thorough penetration and less material deposited on the top side of the work. Doesn't look too bad to my unexperienced eye, only thing I would question based on Greg's (Mr Clean) statements is in the last photo, the backside of the door material could have been sanded clean.......??

OK, here's tonights MIG 101 attempt:

http://sieg.smugmug.com/Cars/Welding...22_oARAk-L.jpg

http://sieg.smugmug.com/Cars/Welding...78_ZkK27-L.jpg

Penetration appears a little lite in areas, but close?

Or........should I take two weeks off then buy a Thermal Arc 185 or Miller 180? :D Reality is I need a RS600 more than a TIG right now. :unibrow:

Seig,

Thanks for the comments. Yea, I'm practicing on the project. Gotta make progress!

Greg,

I am definitely growing attached to the TIG. I need to learn how to feed the rod better. Can't get that smooth. Also, I did not realize the back side was so rusty. I couldn't see it. I actually stuck the camera in the door and just pushed the button. Took several shots to actually get the photo I wanted. It is now on our list to blast the inside of the doors as well. Practice, practice, practice!:lateral:

I think it would be great to have a ''ASK THE FABRICATOR'' section. Lets here what Scott thinks..

Some good points for fledgling welders, but one thing I never see mentioned when giving tips....

Ventilate your work area! Welding fumes can be bad for your health. Excessive exposure can cause a type of parkinson disease.

Work upwind of the welding fumes if outside, and if inside and you dont have a respirator us a small fan to suck the fumes away from you.

Didn't see these mentioned here yet, sorry if I missed it

http://www.shop3m.com/60980013910.ht...Grinding-Wheel

At 3/16 thick they work better than a thin cutoff wheel for grinding down weld beads and they last a lot longer. Can be tough to find locally sometimes though.

still too much build up on top, tacks spaced too far apart and not enough penetration. the little craters in each of the welds should dissapear when you do your next tack. hell, i dont know if i do it correctly or not, but probably 40% of my previous tack will go molten when i do my next tack. too much build up on top makes it like trying to weld sheetmetal to 1/8" plate.

i would turn the heat up a little and hold the trigger for less time. that, or turn the wire speed down a little so you can hold it for a little longer without getting too much build up.

how long are you holding the trigger for? im a "pull-1-2-off" kind of guy. sometimes its forrest gump counting and other times its an auctioneer, but i find a rythm and go from there.

Thanks for the constructive feedback, I agree with all the points mentioned. Being a total newb to it and having limited experimentation time makes the learner curve longer. I typically learn best by hands-on experience but also rely on written input. I'd guess due to fear of burn through and build up I'm not holding it long enough.

Yesterday I fab a clamp device for notching tubing and practice welding tubing and found during my tubing welding experiments that I may be holding the tip off too far as when it was close (IMO) the bead laid down more. Being able to see the bead well enough to relax appears to be a major challenge for me. The size of that damn nozzle doesn't help matter either. :D The Harbor Freight helmet appears to be a little dark even on the lightest setting IMO. An Optrel may be in my future since at 52 my vision is digressing thus compounding the factors.

I'm only on my 2nd bottle of gas in 6 years so more time on the gun definitely an issue though I have made a noticeable dent on the bottle in the last week.

I'll work on experimenting more with finding the extremes, that should help and my self imposed learning barriers will fall.

Thanks for the input, I really appreciate your help and support. :thumbsup:

keep trying and you'll get it. my car has been a 5 year project and i hadnt welded much of anything before i started. i look at some of the first welds i did on this car and almost vomit. its amazing how practice helps.

less stickout can do a few things for you; it will make your placement more accurate, increase the heat and decrease your vision. i find that i get a sloppy gun angle the closer i get, but i do weld much better with about 1/4" stickout.

I try to run 1/4 - 3/8" stick out so the average is 3-5/16th. Maintaining proper gun attitude is the most likely the handicap. I think through the work position, line of travel, and gun position in advance of pulling the trigger but having the talent to reinact it is another thing. :(

To date my tubing weld are inducing a gag reflex. :D

Thanks again. :thumbsup:

Well the tig comes out tomorrow.I'm at a point where the migs not going to cut it anymore.. I need to start learning how to use this thing will see what happens...:_paranoid

Well attemps 1,2,and 3 are utter disasters!! Every night I've been spending a couple of hours trying to figure this tig out. For the most part I can control the tourch and run a nice bead by itself. But when I start to use the wire DISASTER!!! I'm using the mig wire as filler Roger said to start with. I'm having a hard time starting the puddle without burning through no matter how low I bring the amps down. I just ordered a new Optrel welding helmet. I think vision is part of my problem. So will see what happens with the new helmet when I get it...