Welding Tips and Tricks

Hello all,

Getting ready to tackle this project. Welding stainless flat stock into a grid pattern shape. Any advise will be helfull. I have attached a image of what my project looks like. MY goal is to use a Miller Dynasty to TIG with 3/32" stainless filler rod. I plan on using a #7 cup with gas lens and 1/8 tungsten. Some of my concerns are: warpage, keeping it square and overheating. Any advise would be helpful.

Well it is stainless, it will distort. Using 3/32" filler seems too big to me, this (3/32 filler) will require more amps to consume.

What is the size of the flat stock, and what is this grid being used for?

You might be able to tack weld it to your table for a little extra suport.

I'd use 3/32" tungsten and then use the correct filler depending on how much of a fillet you are required. I'm guessing it is 3/8" or 1/2" flat bar. Clamp it tight, move around a lot and use the heat to your advantage. I see it is a circle grid, is it structural?

With that pattern/layout its going to move, just how far depends. What is it used for? How much weld do you need, every joint both sides?, Full welds or stitched? etc...

Ive done similar here and that layout with small pieces can be tough, alignment is a PIA. Last time I did a smaller rectangle grid I notched the pieces and had them slide together. Made it a tight fit, tapped with a hammer and tacked.

LtBadd = Size of the flat stock is 1'' by 1/4 thick. I will be welding two of this grid. In our industry this grid are called Internal FOD Foreign object damage for inside a Rig. to prevent any hazards from entering the flow and damaging parts of the rig.

Rick_H = Question #1 Is not a structural. Question # 2,3 This grid will go forward of the turbine this will be the first line of defense from any objects from reaching the turbine so will need to full welds on avery join.

LtBadd = what is your recommendation on filler rod size? and at What amp would be safe?

Thank you both for answering back!

I'm thinking id try 3/32" filler, 95-100amps...see what it looks like, get in and get out.

I do some grates for our blenders using 1.5" wide 3/8" flat bar, then drill holes and slide round stock through to connect them an make up the grid. Then weld fillets around the seams.Easier to keep aligned and I can put the heat in the 3/4" round bar.

oman,
Are the straps one piece with slots cut in them to interlock, ( I___II___II___II___II___II___I) or are they all individual pieces?

If they're not slotted, I'd suggest that they be slotted. A couple things come to mind when I think about a bunch of small parts welded together in front of a turbine and none of them have a positive outcome. If they're slotted and interlocked then you really only have to depend on the straps themselves not to fail.

The slots would need to be 1/4" x 1/2" deep at the intersection points so they can interlock. Slotted and interlocked pieces would only need a small bridge weld on the 1/4" cross section on each side where they intersect and would cause very little distortion to the overall piece. Making this grid larger than the intake and securing it to the face would all but eliminate any chance of it becoming a calamity.

Just my opinion and how I'd do it if I were to be tasked with such a project.

Len

Braehill,

I have cut all different sizes and milled slots in a solid piece. This are all interconnected as solid pieces with slots.
Flat stock is 1" then I milled down to .520 a little over half the total with.

Thanks for the input

oman,
I'm not sure if you know what I mean by bridge welding, but you would only put a weld from the one side of the slot to the other, crossing the intersecting flat strap. This weld only needs to be 3/4" long and wouldn't be able to distort the metal because it would try to shrink against the captured strap. Doing this on both sides would make it very strong with minimal heat input.

Len

oman1tig wrote:LtBadd = Size of the flat stock is 1'' by 1/4 thick. I will be welding two of this grid. In our industry this grid are called Internal FOD Foreign object damage for inside a Rig. to prevent any hazards from entering the flow and damaging parts of the rig.

Rick_H = Question #1 Is not a structural. Question # 2,3 This grid will go forward of the turbine this will be the first line of defense from any objects from reaching the turbine so will need to full welds on avery join.

LtBadd = what is your recommendation on filler rod size? and at What amp would be safe?

Thank you both for answering back!

Oman I would weld with 1/16 filler, however this isn't written in stone, Rick would use 3/32, we could both probably achieve very close to the same result. Same with amps, set the amps to 100-110 and then use the foot peddle as required, when welding it's all visual under the hood, you can't see the amps on the machine so you need to learn to watch the puddle and control the heat and filler on the fly.

Braehill wrote:oman,
I'm not sure if you know what I mean by bridge welding, but you would only put a weld from the one side of the slot to the other, crossing the intersecting flat strap. This weld only needs to be 3/4" long and wouldn't be able to distort the metal because it would try to shrink against the captured strap. Doing this on both sides would make it very strong with minimal heat input.

Len

This comment from Len is great. For your other issues; clamp the piece down to a thick piece of flat iron. Don't be shy about using a load of clamps. To span the middle, get some square stock - something like 1 1/2" or bigger to span the middle parts. Crib up the sides of the long span hold downs, then clam them out on the edges as close as you can get to your structure. Like the other guys are saying, skip around a lot to disperse the heat. Take your time, let the piece cool.

There are a lot of very skilled craftsmen out here. From reading the few posts, it is very obvious that a few of the guys have experience working with very similar projects.

What is your filler rod? 309L 3/32"? What kind of tungsten are you using? (or did you mention that). Can you post some pictures of other projects that you have completed?

You are into some very advanced work and you need to be proud of the progress you have made in your welding ability. It only gets better from here!
Gary

I

Señores,

Thank a lot for all the feed back. I will start this project soon and let you all know how it turn out.

Stainless is a different animal. I tried building a rack for a gas grille last year. I was fighting with my local metal supplier who promised he could get the stainless in a couple of days that turned into a several of weeks. I had one day after receiving the metal to complete the job. In Jody's words, it came out looking worse than Fido's butt. I was heating up the joints with too low amps and camping on too long. The rods were melting in the middle and falling through the slot in the table to the floor. I got some advice from Otto Nobedder (sp) that is in a post titled "304 stainless rods". I finally came up with a way to shrink the picture file so I'm going to post it here now even though I'm not proud of how it looks. I have not had a need to tig any stainless since then. Don't laugh too hard!

LOL! I just got the metal in to make a SS grill top. Buying the stock was absurdly priced so I'll actually be using 1/8" fill rods. Was going to clamp them to a copper plate and then hit them hard and fast. Did you settle on an approach that you felt worked well?

-Sandow

Edit: I tried it out a few ways and fusion wasn't really panning out. The copper plate certainly helped but a tight arc and 1/16 fill came out the best by far.