Author Topic: Sheet Metal Welding Woes...Need Advice (Read 4321 times)

Bullitt- · « **on:** June 06, 2009 - 11:36:14 PM »

Being totally new to Mig Welding I've read the instructions over & over...Watched the YouTube videos and many hours of TV shows with pros welding on autos.... I can't seem to dial in

1st off I built a cart to hold the welder & tank using moderately heavy steel tube, by the end I was able to make decent welds. Today prior to putting in a small patch I did a few tests on a scrap and on about the 3rd adjustment I had what appeared to be a good setting. A few more test welds & I jump over to the car but didn't get anything like my test welds so I up the wire feed, lower the wire feed, raise the power from the lowest setting from where I started... I had ground to clean metal & sprayed down with brake cleaner, backed with copper but the weld would either burn a hole or spatter badly & make a glob that I could knock off. After reading the instructions tonight for the umpteenth time I'm thinking I may have been holding the tip too far away...

ANY CLUES PLEASE

bb71challenger · « **Reply #1 on:** June 06, 2009 - 11:44:07 PM »

What kind of shielding gas are you using? I would suggest 75/25 as a minimum and although thats what I use I have been told that 92% argon is better for bodywork. If the tip is too far away then the shielding gas is useless also. I like to run 35p.s.i. on the shielding gas. Apart from that it sounds like you just need to get a junk fender from a car dealership(they usually give them away) and just practice. You will find the sweet spot on your welder.

Bullitt- · « **Reply #2 on:** June 06, 2009 - 11:50:04 PM »

My gas is 75/25 set to 25psi...sounds like more is needed. I was practicing on a piece of the old trunk extension that is solid & what I made the patch from.
Why I quit playing golf...can't stand practice

Topcat · « **Reply #3 on:** June 06, 2009 - 11:54:56 PM »

To correct poor penetration (in order of importance)
1. Decrease stickout
2. Increase wire feed speed
3. Increase voltage
4. Decrease speed
5. Decrease drag angle
6. Check for correct gas, if used.

Old metal can sometimes be hard to get it going. And it also burns thru easier. Make sure you have the paint sanded back from weld area at least 1-2 inches away from weld area too. Wire brush really hard too. Use the big wood handle brushes.

Alaskan_TA · « **Reply #4 on:** June 07, 2009 - 12:11:30 AM »

I am practicing myself as time allows.

Go with the smallest wire diameter you can find. Smaller wire / fewer amps / less chance of burn through.

Good link;

http://www.millerwelds.com/education/articles/articles86.html

Bullitt- · « **Reply #5 on:** June 07, 2009 - 12:19:38 AM »

Quote from: Alaskan_TA on June 07, 2009 - 12:11:30 AM

I am practicing myself as time allows.

Go with the smallest wire diameter you can find. Smaller wire / fewer amps / less chance of burn through.

Good link;

http://www.millerwelds.com/education/articles/articles86.html

Maybe this is where I've gone wrong... I thought welding wire would be sized like wire, the larger the number the smaller the diameter....looks like I'm wrong using .030..maybe?

"the thicker the base metal you are using, the larger the wire size. For sheetmetal, .024� wire is a good place to start. If you are welding mostly stock that is 1/8� or thicker, you might want to use .030� or .035�wire."

Alaskan_TA · « **Reply #6 on:** June 07, 2009 - 12:36:02 AM »

All my practice has been with .030 so far.

I did buy some .023, but no chance to try it yet. Make sure you buy smaller tips to match the wire size too.

Long aggravating story involved, but my welding improved about 8000% after I discovered an odd chunk of rubber blocking my gas regulator completely. Glad I found it at least, I was going

bb71challenger · « **Reply #7 on:** June 07, 2009 - 12:59:53 AM »

Going along with Barry's post I do know this, if the weld puckers up and "grows" like a little flower when you let go of the trigger then your shielding gas is either getting blown away by a fan, not there at all or not there in sufficient quantity to do its job. I was laying down some horrible welds at work one day and realized the fan I had directed at myself was actually taking the shielding gas away.

ntstlgl1970 · « **Reply #8 on:** June 07, 2009 - 02:26:15 AM »

I had the same problems using .030 wire when I first started using my welder. Go with the smaller wire (.023") - it's a night and day difference. Seriously - you will kick yourself for not doing it earlier. Also to add to the list topcat posted, cut the "ball" off the end of the wire before making a new weld and using a "push" method will not burn through as fast. Practicing on junk sheetmetal will do wonders for your technique. Practicing on thicker stuff doesn't help as much - I think the thicker stuff is more forgiving.

dutch · « **Reply #9 on:** June 07, 2009 - 04:16:24 AM »

sounds to me like you`re feeding too much wire for the amps you use. also make sure the backside of the sheetmetal is clean from rust and paint too. Post some pics or even better a movie of the area and what you are doing so we can see what`s happening.

torredcuda · « **Reply #10 on:** June 07, 2009 - 06:21:59 AM »

Make sure you cut back the metal far enough as even though the surface may look nice and clean sometimes it is still rusty on the back making it thinner and you will have blowout..023 wire should allow you to use a lower heat setting and try "stitch" welding where you just do a short weld and let cool,do another one let cool etc. rather than trying to do a long continuos weld.

hemiken · « **Reply #11 on:** June 07, 2009 - 07:31:59 AM »

you guys in the states have a different set up to what i use hear. I use what is called .6mm it would be equivelant to your thinner gauge wire of 23 thou i guess. The secret is that you use a smaller wire to lesson the heat transfer along with the build up that needs grinding later, less wire equals less grinding. And as for gas, i only use 12 psi for welding, anymore is a waist, this is strictly indoors of course, out doors is a fighting match with mother nature and gas can blow away from the nozzle so easy. I suggest you get the thinnest tin you can Wade, and try welding it with a pulsating action all done by finger, this means pulling the trigger on and off. The biggest thing you will need is to be able to see what you are welding, the better your vision, the better you will weld, that is a fact. Watch for the sheet metal to glow and then cool when welding, if it glows too much it will sink and make holes. When traveling along a panel that has length, be prepared to give it time to cool after you do each very short section of weld as it will distort the panel to a through away panel very easy.

Bullitt- · « **Reply #12 on:** June 07, 2009 - 10:34:43 AM »

Thanks a bunch guys...I'll be tracking down some .023 wire & tips +++doing some practice before I hit the car again.

E-Body Products · « **Reply #13 on:** June 07, 2009 - 02:49:39 PM »

I usually weld with my welder set on the following:

Wire speed 45
AMPS 1 or 2 for thin stuff
AMPS on 3-4 for plug welds... (Make sure you get penetration on all plug welds)

Like others have stated above, make sure the surface is clean of paint, oil and rust. If you use a rust preventive coating, make sure you use 3M weld thru primer. Regular primer will cause disaster and your welds will look like this

Stitch welding works the best and spread each tack weld out along the panel so you can keep coming back the each one and evenly distribute the heat as you work. I like to start my next stitch on part of the previous tack made (The metal is thicker here and less likely to blow out).

I am not an expert, but this seems to work for me. I learned on a set of floor pans that I installed by butt welding them in place. Lots of welding and grinding. Then, the new 1 piece pans became available and I replaced. Full panel replacement with plug welds is much easier to me and provides a much better result when finished.

Daniel
www.ebodyproducts.com

farmertan · « **Reply #14 on:** June 07, 2009 - 03:59:22 PM »

Do like I did a few years ago, go to your local skill center for high school kids and sign up for there next adult class. Held on sat. mornings for about two months and you will burn through more material than the cost of the class and when your done you will be a fairly competent welder.

Author Topic: Sheet Metal Welding Woes...Need Advice (Read 4321 times)

Bullitt-

Sheet Metal Welding Woes...Need Advice

bb71challenger

Re: Sheet Metal Welding Woes...Need Advice

Bullitt-

Re: Sheet Metal Welding Woes...Need Advice

Topcat

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Alaskan_TA

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Bullitt-

Re: Sheet Metal Welding Woes...Need Advice

Alaskan_TA

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bb71challenger

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ntstlgl1970

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dutch

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torredcuda

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hemiken

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Bullitt-

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E-Body Products

Re: Sheet Metal Welding Woes...Need Advice

farmertan

Re: Sheet Metal Welding Woes...Need Advice

Author Topic: ***Sheet Metal Welding Woes...Need Advice*** (Read 4321 times)

Alaskan_TA

Alaskan_TA

Author Topic: Sheet Metal Welding Woes...Need Advice (Read 4321 times)