Welding a section into a truck frame

[steelwarhorses]

The truck frame had some rust holes in it so I cut sections out on both sides, I cut out a piece to fit in the rectangle I cut out. I'm new to welding and I'm doing this with my Millermatic 250x. First the frame rail is thin as it is. The material I'm welding it in is approx .1875 The problem is the top of the weld. The bottom, I run the bead on the thicker metal I'm welding in and the puddle leaks down into the thin metal and is doing pretty good. It's the top, I'm struggling with. I've tried running the bead along the top but I can't get it to the existing thin metal. I can't weave or it would just burn through the existing frame metal. I've then resorted to turning the machine down to where it won't burn through the thin frame metal and trying to at least get some metal bridge between the two. Best case I'm going to have a ton of grinding to do, worse case it's still burning through the thin metal making the gap between the new metal and old a little wider.

I'm using Esab dual shield flux core .035. I have some regular .035 wire. I'm hoping there is a better way. if so I'm open to ideas. Again I'm a novice with more reading and watching than actual torch time.

Thanks

[Aeronca41]

Sounds like you didnt trim back to full thickness metal--and welding a rectangular piece into a frame is most likely not a structurally sound way to do the repair. Each of the four corners will likely be a stress riser point and potentially generate new cracks if the frame flexes. The weld "leaking down" onto the thin metal Is pretty shaky from a structural viewpoint, to put it mildly.

Your solid .035 wire is not going to be any help; won't work in rusty metal---flux core is the correct material.

Please get someone with welding experience, in frame repair if possible, to look at this. Understand you came here for help, and I dont mean to be a downer, but depending on where in the frame you are welding, it is possible you are setting yourself up for future problems and perhaps danger. Rusted out vehicle frames are not a good place to learn to weld. Do yourself a favor and get a qualified person to look at this.

[Dobermann]

I'd suggest that if you can't get back to material thick enough to hold a weld bead, you may be in more corrosion trouble than you thought. Typical frame section, even for unibody, is going to be on the order of 14 gauge as a minimum and if you can't get a bead on that without blowing through than you may be on a hopeless job.

If you have any oxy/acetylene experience you might have better luck with that. But you really need to question the overall integrity of the structure if you're having this much trouble welding it.

[Forced_Firebird]

Have you tried running a bead with the machine turned down on the thin metal to "thicken" it, then pull the thicker material into the previous weld bead?

I run into this often when welding 1/8" and 3/32" floor plates on roll cages to 22-20ga floor pan material (often thinner due to prep and/or corrosion). I also find it helpful to "push" the wire/puddle into the weld, rather than "drag" it - heat the thick material and push the puddle into the thin, but be quick about it so the pool doesn't settle on the thin stuff for tool long. Also, it helps tremendously if you run small beads at a time (1" or less, then move to a new spot) to keep the surrounding area of the thin metal from heating up.

Are you sectioning the frame for lowering/suspension purposes? Is this going to be weight bearing, or cosmetic repair?

[steelwarhorses]

I'm just looking for welding tips. The integrity as it is in the location, I'm welding, the truck is 6,000 lbs and I put the lift pad on it (2 post) and lifted the truck up under where I ended up cutting without any issue. (Jack stands all around in other structural places so I don't hear about that.

I could have left it alone and most likely the frame would still outlast me. But I'm doing some other things, learning how to weld and giving this a go. If I felt there were real structural issues, after I fill the hole up, I'd put a piece on the outside and weld to where it bends at the top and bottom.

I also have a friend with 20 years of stretching and shortening large truck frames I consult with and actually ran this by, he gave me the flux and told me to try and run the bead on the thicker metal, I'm just not having luck on the top and hate calling him ever afternoon asking questions.

Plus if it were completely ate up, I could just replace it with another frame rail. This is a farm vehicle I tinker around in.

Anyway, I'm not looking for anybody to assume or worry about liability on the structural part.

I do appreciate the concern but for now I'm just looking to figure out how to weld two pieces when one is thinner than the other and they are vertical.

_____________________________ Upper piece - This is thinner
--------------------------------------------------- lower piece - This is thicker

Dobermann, I don't have oxy/acetylene

The "Leaking" down is to get the gap filled and I'm going to be going back try to run some overlap beads on that. Again if nothing else, this is just to fill the hole I created and I can use another piece on the outside to connect the top and bottom welds of the frame rail. There is still great thickness there in this area.


Tonight if nothing else, I'm going to try and figure out the heat and wire speed to start running beads on the top piece and overlap till I get to the thicker piece and do a lot of grinding.

Thanks for the input.

[Olivero]

What I do at times of filling gaps, which happens a lot because I Am really bad at cutting angle grinders or notching pipe is to run a bead and stop, let it cool, wire wheel it or whatever and run another to kind of fatten it up a bit or depending on the direction, fill the hole to a point of being able to make the 2 pieces connect, then you grind all the ugly stuff off and run a real bead now that you have a surface to join on.

[steelwarhorses]

Have you tried running a bead with the machine turned down on the thin metal to "thicken" it, then pull the thicker material into the previous weld bead?

I run into this often when welding 1/8" and 3/32" floor plates on roll cages to 22-20ga floor pan material (often thinner due to prep and/or corrosion). I also find it helpful to "push" the wire/puddle into the weld, rather than "drag" it - heat the thick material and push the puddle into the thin, but be quick about it so the pool doesn't settle on the thin stuff for tool long. Also, it helps tremendously if you run small beads at a time (1" or less, then move to a new spot) to keep the surrounding area of the thin metal from heating up.

Are you sectioning the frame for lowering/suspension purposes? Is this going to be weight bearing, or cosmetic repair?

Thank you, exactly what I'm looking for.

I've had this vehicle for a while and noticed some small holes in the frame in once section of the frame.

What happened is mud has gotten into it and over is 26 years, this is the low spot on the frame and settled here. Right now, this is for cosmetic. I could have welded a piece to the top and bottom of the frame but I wanted to cut it out and see if I could get the sections welded back in and ground to where you couldn't tell anything was done. (More practice than anything else.)

I'll try pushing, as I was trying to pull. Last night I was kind of pulling the trigger for a second and bouncing to different places like you suggest. It was kind of working here and there.

But my skillset right now, I'm going to have to do a lot of grinding.

I'm definitely not modifying the frame nor does anything mount to it here. I'd probably replace the frame rail if that were the case.

[Aeronca41]

Sounds like you are doing OK. Couldn't tell from your original post your level of experience. No attempt to put you down, just concern if you were a complete newbie on your own potentially headed for trouble. Hope you get it fixed. Great advice from Forced_Firebird. I have used those techniques quite successfully.

[steelwarhorses]

Sounds like you are doing OK. Couldn't tell from your original post your level of experience. No attempt to put you down, just concern if you were a complete newbie on your own potentially headed for trouble. Hope you get it fixed. Great advice from Forced_Firebird. I have used those techniques quite successfully.

I didn't take it that way. I always get in a quandary because if I put all that kind of info in to start, then it's too long or comes across wrong.

Anyway, looking tonight I should have started this up an 1" higher as the metal feels about the right thickness there. I'm going to practice running some beads from there down and hopefully that will get me into my filler piece. Thanks again for the input. I appreciate it.

[ryanjones2150]

I don't think dual shied would be my choice for filling a hole or gap. I say that because you're going to stitch it. You really need to remove the slag between stitches or spot welds. That will take forever. Don't get me wrong, I love dial shield, but not for this application. Just my input.

[steelwarhorses]

Thanks for the tips. I cut a little more out and had to go back and forth on wire speed and temp and pushing definitely helped. I cut the sections out free hand with my plasma and the replacement pieces free hand so I had some gaps. I found a setting where I penetrated the thin and a little of the puddle would sag down and eventually I bridge the gap. A little here and a little there as suggested. I had to only wait usually for the metal to cool till it wasn't red and I could hit it again.

Then once it got to the thicker metal I turned up the settings and ran a couple of rows As pointed out I initially chipped after every little thing, But I just started going back over it without chipping every time. (If that ends up causing a problem, I'll grind down and redo it.)

The metal is clean on the outside so I may try the non flux I have. The sections I've got I've hit with a hammer and it's still open on one end and sounds and feels solid.

Again thanks for the tips. I'm having to grind more than I should but finally getting results that I think are going to be solid.

[H80N]

Any chance of posting some pics...???

[ryanjones2150]

You will have slag inclusions if you aren't chipping the slag between spot welds. <br />
<br />
I do my fair share of welding on old car iron. Sometimes it makes you pull your hair out when you start getting little volcanos in your weld. I have found, and maybe some others have some suggestions, that the esab spool arc wire performs much better on less then clean metal as compared to the Lincoln stuff. And that is a solid wire. I was welding yesterday on some trailer parts that were rusty and powder coated. It did well, not perfect, but it was fine. <br />
<br />
Another option that has worked well for me is to tig weld it using 309 filler metal. It's like a magic wand, that weld puddle starts bubbling spitting and sputtering....push a little 309 in there and it will instantly smooth out.

[steelwarhorses]

Thanks everyone. I'm posting this to refer to later and hopefully help others.

I've been delayed on this but I got a Multimatic 215 yesterday. A friend told me .035 wire may be too thick and to try .023. So I got the 215 to setup with .023 and set my 250x at .030.

Anyway, the 215 I forgot .023 tips so I ground everything clean and put the .030 wire in. (Non flux or shield.) I set the 215 to 3/16 and pulled the trigger and it blew a quarter size hole in what I had fixed up. (The smart settings on this thing don't appear to be that smart but that's a topic for another discussion.) So I took it off auto and turned it down to 16.9 v & wfs 163 and WOW. (Auto was 19.6 & 430 wfs if I recall.)

Using the push technique like suggested here, I started out above the holes and used an upside U like motion to push the puddle down. With those settings it's almost like using a caulk gun. The puddle, like a caulk is laying a 1/16" layer down about every pass and it just closes the holes right up but doesn't drip if you go the right speed.

I'm getting good penetration as well where I'm getting about 3/16 or a little less on the passes I'm making. Since my goal is to end up with the frame smooth like it was from the factory I'm going to have to do some grinding.

I'm taking some pictures as I go and when I get finished I'll try to post them here with anything else I learned.

Thanks everyone for the input!!!

[steelwarhorses]

Some pix.