welding

[jimmy828]

i tried my luck at welding.I bought myself a mig welder and practiced on some scrap metal before replacing floor pan and cab mount on 69. I done a 1/2 in. overlap and stitched pan from both sides.Used the parts from dennis carpenter. I must say the parts fit pretty good. I had to tweek them very little.I made sure i took pics and measurements before replacing parts. Seam sealer was added inside and outside after pics were taken and also holes were drilled in cab mount. Any tips for a rookie welder would be appreciated.

[67mann]

Jimmy.....looks good from what ya can see in pic's.....what tip's are ya lookin for or what problems did you have when you were welding Practice,practice,practice and even finding a Adult Vocation class will help ya understand the basic principles of welding.Practical hands on will give you the most education. With sheet metal it's best to move around..not welding continous(distortion)on one seam. IMHO butt welding is better than lapping.....then your only welding once not twice.

[67nukeford]

Jimmy, I pretty much did the same. Wife got me a Mig welder for christmas, and had a buddy who welds come over and get me started. Did a ton of practicing, then got busy on the truck. Didn't have to do the whole cab floor, just a few patches, but I also did the cab mounts. Like 67mann stated, butt welds would probably be better for sheet metal welds. Moisture can get into the space between the laps and cause issues later. Big thing I've learned, is to make sure everything is clean. Having contaminants on your welding area can cause all sorts of problems.

Cab looks great, though! Did you have any fitment issues with the DC cab mounts? Mine were not welded together properly from DC. I actually got a set from them the second time that were not welded together, so I could fit them pefectly to the cab, then spot weld them myself!

[jimmy828]

thanks for the tips, i did make sure i sanded the paint,rust, etc. away before doing any welding.Before i painted the inside of floor pan i grinding down the welds and applied a thin coat of bondo glass then sanded it down and painted it.I am going to have to learn how to do a good butt weld.Sorry about the pics, that is as big as i know how to get them.

[flyboy2610]

One key when doing a butt weld is to leave a gap about dime or nickel thickness all the way along the seam you plan to weld. When metal gets hot it expands. If the part to be welded is snug up against the base metal, when the metal expands you WILL get a warp. Leaving the gap allows some room for the metal to expand without warping. The metal from the welding wire will easily fill the gap as you weld. This is more important in the thinner gauges of metal as compared to say 1/2 plate steel.
For sheet metal, I really recommend you get a gas setup for your welder, if your welder can use gas. You can get solid wire in smaller diameters than you can with flux core wire. If you use gas, use it indoors such as the garage or outdoors on a very calm day. Wind will blow the shielding gas away and then you get porosity in the weld, which is basically a whole lot of little air bubbles. These make the weld very brittle and virtually useless. Flux core wire has a flux core surrounded by a metal sheath. The core melts and creates a protective gas for the weld, so it's good if you must weld outdoors in a breeze. But it does not have the benefit of the cooling effect of the shielding gas, so it runs much hotter and your risk of burning through light gauge metal is greater. The core also gives off a lot of smokes as it does its thing, so it's harder to see the weld clearly as you make it. I try to avoid using flux core as much as I possibly can.
When you do sheet metal, do not weld more than an inch or two in one spot. Move around frequently to avoid over heating the metal. Concentrate on the puddle of molten metal, not the arc. Let the puddle form and then practice making it go where you want it to go without losing it. Most people try to weld too fast. Learn to "Get on it and go" as my welding supervisor at work used to say. Get yourself a good auto darkening variable shade helmet.
Practice, practice, practice.
Your welds look pretty good from what I could see.

[White Knight]

I am an autobody instructor and have taught MIG welding for over 16 years. My students love MIG because it is so easy to do, and can usually join metal within the first hour of practice. However, there is welding and there is good welding that results in "stronger welds then the original steel."

A trick I tell my students is to set the welder voltage and wire at the same number, say for 18 Ga. steel--4 and 4 or 3 and 3. Adjust your gas to 15 lbs.. no more than that, as you're just wasting gas. (By the way; most MIG's suggested setting's on the inside of the welder door-and mostly are NOT accurate-go figure) Use the lowest heat setting you can, so as to prevent burn-throughs.

Here is the important part: using a flash helmet, resting the MIG nozzle on it's side, sting the practice metal, while drawing the nozzle slowly across the steel ADJUST THE WIRE SPEED KNOB UP OR DOWN UNTIL YOU get the sound of meat sizzling on the grille. A happy MIG sounds just like it.

Popping, skipping and other sounds mean voltage or wire settings are wrong. This rule of thumb idea works on any MIG. Be sure the nozzle is clean without slag shorting between the nozzle and tip. This is also a common problem.

[BobbyFord]

I am an autobody instructor and have taught MIG welding for over 16 years. My students love MIG because it is so easy to do, and can usually join metal within the first hour of practice. However, there is welding and there is good welding that results in "stronger welds then the original steel."

A trick I tell my students is to set the welder voltage and wire at the same number, say for 18 Ga. steel--4 and 4 or 3 and 3. Adjust your gas to 15 lbs.. no more than that, as you're just wasting gas. (By the way; most MIG's suggested setting's on the inside of the welder door-and mostly are NOT accurate-go figure) Use the lowest heat setting you can, so as to prevent burn-throughs.

Here is the important part: using a flash helmet, resting the MIG nozzle on it's side, sting the practice metal, while drawing the nozzle slowly across the steel ADJUST THE WIRE SPEED KNOB UP OR DOWN UNTIL YOU get the sound of meat sizzling on the grille. A happy MIG sounds just like it.

Popping, skipping and other sounds mean voltage or wire settings are wrong. This rule of thumb idea works on any MIG. Be sure the nozzle is clean without slag shorting between the nozzle and tip. This is also a common problem.

Good tips, thanks

[huskerrush]

I am an autobody instructor and have taught MIG welding for over 16 years. My students love MIG because it is so easy to do, and can usually join metal within the first hour of practice. However, there is welding and there is good welding that results in "stronger welds then the original steel."

A trick I tell my students is to set the welder voltage and wire at the same number, say for 18 Ga. steel--4 and 4 or 3 and 3. Adjust your gas to 15 lbs.. no more than that, as you're just wasting gas. (By the way; most MIG's suggested setting's on the inside of the welder door-and mostly are NOT accurate-go figure) Use the lowest heat setting you can, so as to prevent burn-throughs.

Here is the important part: using a flash helmet, resting the MIG nozzle on it's side, sting the practice metal, while drawing the nozzle slowly across the steel ADJUST THE WIRE SPEED KNOB UP OR DOWN UNTIL YOU get the sound of meat sizzling on the grille. A happy MIG sounds just like it.

Popping, skipping and other sounds mean voltage or wire settings are wrong. This rule of thumb idea works on any MIG. Be sure the nozzle is clean without slag shorting between the nozzle and tip. This is also a common problem.

Good tips, thanks

Very good stuff. Just got a little MIG welder for Christmas myself. Spent a couple of days last week trying to see what I could practice on....