Neal Wright
Oct 7th, 04, 9:18 PM
Figured I would post this, as I am about as novice at it comes at welding ... few times in college, and on the farm but nothing pretty.
I've been burning wire on my floor pans for a week now, and seem to have developed some pretty good techniques for this task at least.
The crossmembers were tricky. The original crossmember is heavy (~16ga), and my replacement pans are VERY thin from Year One (won't recommend). The thing I found here was to use 3/8" holes for my plug welds, and a very high heat setting (C on my lincoln) ... put the wire in the center of the hole on the crossmember only (do not touch the thin metal) ... now start my weld ... get the crossmember good and hot welding (it's only a split-second) ... then drag my molten puddle towards the drilled hole of the new floor pan, but do not actually touch it with the electrode ... only let the molten puddle barely touch it ... then quit.
What I'm finding with this technique was that it was hard to figure out how to weld a 16ga crossmember to a 20ga panel. Touching the electrode to it will burn through it instantly, but the molten puddle is hot enough to melt and fuse the two together.
Another I found was the butt weld joint I'm running around the perimeter. I sweated this for months ... would a novice like myself be able to accomplish this, or just waste my $100 panel? Well I got the panel cut pretty good, but there are definitely areas that have a 1/16" gap that I just kept burning through when trying to weld.
Here's what I found for this ... do not try to weld lengthwise around the perimeter, the thin metal wouldn't take the heat even on my lowest setting.
Where I have this gap, weld like a cross-stitch from the top -> down. Start about a 1/8" on the upper portion (which is actually my heavier original floor) ... strike a weld, and bring it down. When it reaches the gap, it IS going to burn through ... but just keep the trigger pulled, and steady go down about 1/8" over the newer metal (thin). Now continue to hold the trigger, and go back up with it back over top of the original panel ... on the upward movement, the metal is still hot and flowing and the additional metal added will be able to bridge the gap.
I also knew this from college, but I will pass it on ... MIG welders are hard to tell if you fused anything or not, trust me if you're green to this you can look down and think all the metal on top represents a good weld and then have it fall apart in your hands.
On instances like my floor pans that you can look on both sides, you want to see melted or fused metal on the back side too. My crossmembers I'm actually burning hot enough to almost leave a puddle looking drip underneath. The thin stuff is hot enough to see the metal melted, but no puddle underneath.
Anyhow ... just felt like passing this stuff on, that a novice really can learn to to do these panel replacements. It just takes time/patience ... I'm well into the teen-hours to replace my driver's floor so far.
Thanks, Neal
I've been burning wire on my floor pans for a week now, and seem to have developed some pretty good techniques for this task at least.
The crossmembers were tricky. The original crossmember is heavy (~16ga), and my replacement pans are VERY thin from Year One (won't recommend). The thing I found here was to use 3/8" holes for my plug welds, and a very high heat setting (C on my lincoln) ... put the wire in the center of the hole on the crossmember only (do not touch the thin metal) ... now start my weld ... get the crossmember good and hot welding (it's only a split-second) ... then drag my molten puddle towards the drilled hole of the new floor pan, but do not actually touch it with the electrode ... only let the molten puddle barely touch it ... then quit.
What I'm finding with this technique was that it was hard to figure out how to weld a 16ga crossmember to a 20ga panel. Touching the electrode to it will burn through it instantly, but the molten puddle is hot enough to melt and fuse the two together.
Another I found was the butt weld joint I'm running around the perimeter. I sweated this for months ... would a novice like myself be able to accomplish this, or just waste my $100 panel? Well I got the panel cut pretty good, but there are definitely areas that have a 1/16" gap that I just kept burning through when trying to weld.
Here's what I found for this ... do not try to weld lengthwise around the perimeter, the thin metal wouldn't take the heat even on my lowest setting.
Where I have this gap, weld like a cross-stitch from the top -> down. Start about a 1/8" on the upper portion (which is actually my heavier original floor) ... strike a weld, and bring it down. When it reaches the gap, it IS going to burn through ... but just keep the trigger pulled, and steady go down about 1/8" over the newer metal (thin). Now continue to hold the trigger, and go back up with it back over top of the original panel ... on the upward movement, the metal is still hot and flowing and the additional metal added will be able to bridge the gap.
I also knew this from college, but I will pass it on ... MIG welders are hard to tell if you fused anything or not, trust me if you're green to this you can look down and think all the metal on top represents a good weld and then have it fall apart in your hands.
On instances like my floor pans that you can look on both sides, you want to see melted or fused metal on the back side too. My crossmembers I'm actually burning hot enough to almost leave a puddle looking drip underneath. The thin stuff is hot enough to see the metal melted, but no puddle underneath.
Anyhow ... just felt like passing this stuff on, that a novice really can learn to to do these panel replacements. It just takes time/patience ... I'm well into the teen-hours to replace my driver's floor so far.
Thanks, Neal