mig and flux core tips and techniques, equipment, filler metal
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taylorhudson166
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Hello all,

Brand new welder here. I've been practicing beads with my Hobart 130 amp and I'm ready to start my first project. I'm fixing to build a shop table that will double as a welding table for various tinkering.

The legs for my table are going to be 3" or 4" 1/8" square tube welded to 3 foot by 6 foot 1/2" steel. I'm thinking I'm going to reinforce the legs with framing and a shelf about 12" up the legs and some framing under the metal slab. 2" 1/8" square tube.

So my questions are as follows: I understand 1/2" plate is beyond the limits of my machine but I'm not building anything structural; it's just a table that will take some light abuse but nothing crazy. I will set my machine to it's max and weave the puddle into the thinner legs so as not to burn through. In your guys' opinions will this weld be strong enough for what I'm doing? Do ya'll see any issues with my design?

Thanks a bunch
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Personal opinion, don't weld to the table.

Good chance it will warp and that'll bug you every time you layout something that needs to be straight and flat.

Weld the legs to stretchers that the table sits on - in other words, make a complete frame.

The table can then be bolted on and adjusted for flatness this way.
Dave J.

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MinnesotaDave wrote:Personal opinion, don't weld to the table.

Good chance it will warp and that'll bug you every time you layout something that needs to be straight and flat.
Completely agree. Ask me how I know. :lol:

Do NOT weld to the table. Bolt it down.
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cj737
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I differ from the others. A few 1” stitch welds spaces along the frame will NOT warp your table and will be more than strong enough to hold it to the frame. I’d use a 3/32 7018 rod and clean the mill scale first. Burn it in st each corner, once or twice along the sides, DONE.

You only need to secure the top to the frame, it’s not a massively structural weld for Pete’s Sake.
PeteM
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I'm with cj. Don't do that for my sake. I don't need big welds on 1/8th inch steel.

On that subject, typically a weld only needs to be the size of the thinner metal.
taylorhudson166
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Dang now I’m torn. Maybe I will bolt it down but I like the idea of a few stitch welds too.

I read somewhere that when welding two different thicknesses you’re supposed to set your machine to the thicker metal? You guys disagree?

Finally is 1/8” 3” legs with 1/8 2” square tubing for framing strong enough? The top weighs around 500 lbs I think.

Thanks for all your help!
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taylorhudson166 wrote:
Finally is 1/8” 3” legs with 1/8 2” square tubing for framing strong enough? The top weighs around 500 lbs I think.

Thanks for all your help!
More then strong enough.
Bolt or weld the table top, either will work, however if in the future you want to modify the table, being able to remove the top by unbolting would be easier
Richard
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homeboy
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My first table 3x6ft I had the local shop fabricate the top frame- perimeter and 2 lengthwise center members all 11/2x21/2 x1/8 RST on their big flat welding table. With the flat frame I built the rest of the frame -legs-11/2x3/16 RST-- shelf supports etc upside down shimmed tight on top of an old heavy wooden work table. when that was done I picked up the frame (2ton cherry picker)and slid the top under--1/4in plate-- clamped and tacked slowly staggered aprox 2ft o/c ea side of frames. then flipped and set flat to weld on feet for wheels and flat expanded metal for shelf. Clean and paint. No warping and flat. Built 2 more of different sizes on top of first. If building your own top frame to get a flat plane square your top outer frame members (6in welding magnetsa big asset) and pull a string tight corner to corner in an X. Shim the top string ( I use a popsicle stick for a spacer) so it just clears the bottom string. Shim the frame corners until the 2 strings barely touch where they cross. You have a flat plane. My info if it's correct is 1/2in plate is 20lbs per sq ft X18 =top 360lbs or 90lbs per leg for the top itself.After that is whatever you load on it.My feeling is 3-4in legs might be overkill. Maybe someone can calculate what they would carry being pinned at the top and laterally supported at aprox. 12in level with welded shelf supports. The first one I built with a Lincoln 100 flux core only and it worked fine. :D
cj737
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I like to use leveling casters on my tables. Allows me to level the table and set it, or, move it when necessary. My table weighs nearly 2,000# so a floor jack is helpful when shoving it around (sometimes do large projects that won’t quite fit and allow walk around space.

Your frame is plenty strong for what you’re planning. If you can, lay the top flat on the ground, frame upside on it. Weld the frame to the top with a few stitches. This will keep the surface flat and limit distortion. Once done, flip it over (friends are helpful for this step) and roll it into place. Flux Core or hard wire MIG will work fine, just clean the scale first. Or Stick stitch it.

A helpful hint: make your frame smaller in area so the top overhangs on all 4 edges by about 4-6”. This leaves you clamping room and won’t hurt your stability.
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When I made my table I welded the frame and had planned on welding the 1/2" top to it, When I went to my local metal supply and they loaded it with a fork truck I thought maybe I don't need to weld it. lol So I didn't and for 15 years or so it hasn't moved unless I want it moved..
Pete



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taylorhudson166
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Wow thanks for all the info dudes. I was planning on an overhang but I hadn’t thought about wheeling it around for bigger projects maybe I’ll do leveling casters as well! I was planning on making the frame first then buying the top bc I hadn’t considered the importance of a level table. Dumb I know. I think I’ll buy the steel and build the frame on the floor of my garage and then flip it. I like the idea of using larger legs mostly for asthetics. I thing I calculated about the same weight.

Any other tips are more than appreciated. I’ll be sure to share pics but won’t be until after the first of the year. Waiting on s few more tools from Santa. Cut off saw, gas cylinder etc ;)
cj737
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Grab a nice thick piece of stainless rod, about 2-3” long and 1.5” in diameter. Weld it to the base of a leg and use it as a ground clamp for your welding. Doesn’t rust, out of the way, and solid ground every time.
homeboy
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Tell Santa you want a dry cut saw :lol: In my opinion it's more important to have a flat plane than having the table horizontaly level unless you want to set up projects with a level instead of square and angle finder. Leveling casters are good if your floor isn't fairly flat, or for a table that doesn't move around much. In my smaller shop tables are frequently moved around to fit the job, the floors pretty decent and I never notice it if it's not sitting perfect. :D
taylorhudson166
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Just wanted to give you guys an update. Finished my table. Used 1/4 for the top. I framed it in 6” from the edge and wish I had only done 2”. It went ok being my first project and all. Thanks for the help.
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cj737
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Glad you got it done. I notice a couple of safety issues in your picture:

Rug/carpet at your feet- that's pretty flammable if you are welding with MIG or Stick. The sparks will catch that on fire, especially if there's any chemicals embedded. Swap that for a thick piece of open core rubber matt.

Drywall untreated is not the best surface as it too can catch fire. Grab a thin piece of sheet steel, screw it to the drywall/studs to cover your immediate work area. 22 Gauge is plenty. Might cover the peg board area too as a precaution.

Your gas cylinder on the floor, while "trapped" behind that rolling shelf, wants a strap around it to prevent it from tipping over, especially with your regulator installed. It won't explode, but if it does tip and knock your regulator off, your tank will become a missile and do severe damage. Trust me, the frequency of this is much higher than you realize. A simple chain with carabiners hooked to an I bolt screwed into the wall is enough.

Regarding the thickness of your table, since you dropped to 1/4", you can still weld small extensions from your top frame, outward to create more support under the surface overhang. 1/4" unsupported is a bit "droopy". Just grab some square tubing (2"x2"x1/8") and weld the end to the frame. Then a couple of small tacks to the top and you're in business.
taylorhudson166
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These are mostly things on my list to do. I’m fixing to make a welding cart, mostly for more practice but that’ll take care of my bottle. I’m not so concerned about the drywall as it is inherently Fire resistive but I hadn’t thought about the peg board. I could see fire getting behind there and running into my attic.

I’ve got leftover 2x2 and am going to try to brace it out like you suggested
Terry K
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I also have a 3x6 welding table, with 1/2" plate top, i clamped and stitch welded every 6", once the top was in place, leveled and shimmed where needed,welded angle iron brackets to the feet and bolted down, table sits dead straight and level in all 4 directions
WildWestWelder
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The way I welded my top to the table frame was to cut small wedges that I would insert in any gaps between the top and frame. Right next to the wedge I would put a tack. The wedge vastly minimizes tack shrinkage as well as the tack itself is so small that its pulling power is not much. I would work my way around the frame about every 12" or so. I then went back and put a 1" stitch next to every other tack. Result; table is as flat as when I put it on and securely in place. You can use this method help straighten a top also by tacking at the high parts and driving a wedge to lift the low sections. But, it's best to buy as flat as you can get and need. JMHO YMMV
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