Welding Tips and Tricks

Hey guys,

been welding for a while now, took a few classes over the last 4-5 months got a few basic certificates and only recently I bought a little stick/tig inverter to play with at home.

Here's my first attempt at fabricating something meaningful, a basic little welding table.

I have made a few fishing rod holders and other assorted simple items but the table was the first project I had to pay careful attention to angles and lengths etc.

I don't have a top for it yet, if I can't find some cheap plate to do it in 1 piece i'll probably end up using a few 'slats' of flat bar, as buying a full plate of steel is way too exxy for what this is.

I ran out of angle for the bottom shelf frame but thinking about it I think i'd prefer to leave the front of the bottom shelf open anyway, that way I have easier access to get things in and out of it while it still has a lip to contain things around the back and sides.

the welding isn't real pretty on this table but I was placing way more emphasis on keeping things square and fabricating. I only had SS 316L electrodes on hand so that's what I used

All the miters were cut on an abrasive chop saw and I made frequent use of 4 home made 90 deg. fixtures which made things easy. start to finish (well, the stage its at in the photos) took me about 1.5 full days but I had fun and i'm happy everything came out flat and square






any comments tips or suggestions are welcome, harsher the better

Nice looking table. Flat and square is more than half the battle. I like your 90 degree fixtures, too, might have to make a few myself.

If I can make a suggestion for the top.....I always use 3/4 MDO plywood for any welding tables I make. MDO is a flat paper coated plywood mostly used for sign work. The paper coating lets you put layout lines right on the table, you can screw in clamps wherever you need them, you can drill for any weird placed clamps or fixtures, and you can replace the top whenever you need to fairly cheaply and easily. Of course the lywood will tend to smolder or burn if you're welding right on it, so I always spray it with a flame retardant spray and let that soak in good. It helps alot.

If I can make a suggestion for the top.....I always use 3/4 MDO plywood for any welding tables I make. MDO is a flat paper coated plywood mostly used for sign work. The paper coating lets you put layout lines right on the table, you can screw in clamps wherever you need them, you can drill for any weird placed clamps or fixtures, and you can replace the top whenever you need to fairly cheaply and easily. Of course the lywood will tend to smolder or burn if you're welding right on it, so I always spray it with a flame retardant spray and let that soak in good. It helps alot.

Whats the point of havin a welding table if every time you weld on it you start a fire?! :p

What I did on mine is take some 3/4" or 1" pipe from home depot and space em out about 8 inchs on center. You could use flat stock or even angle(angle would make it nice and stiff, as I'm having problems with my top sagging down, but I abuse the HELL outta my table). I cleaned up a piece of pipe right in the middle of the table for my work lead too.

I've had mine for over a year now, and I definately wish I would have built mine sturdier-I used 1-1/4 x 1/8" angle, and I really wish I would have used some 3/16" material.

edit-I remember at the airport they used, for lack of better understanding, structural sheet rock? It was sheet rock with sheet metal on one side of it. It was then, you could screw it off with regular self tappers-That might be a better/more permanent alternative than plywood.

The plywood will burn if it gets hot slag dropped on it, but the flame retardent will stop it from spreading. The sparks won't catch it on fire either if it's sprayed beforehand. I like the idea of a sheetrock tabletop, though. Hadn't thought of that, but I work in a woodshop so I get all the plywood scraps I want for free.

I love the fixtures as well. Great idea!

-Rick

Thanks for the suggestions guys. I have a about a metre and a half of 50x50x6mm angle (2"x2"x1/4"), I reckon what i'll do is cut it up and weld a few braces running widthways across the frame, will fit about 3 in there, then use 1/4" flat stock and run it lengthways across the top of the angle supports. the table frame is made of 35x35x3mm square tube and the angle bracing on the bottom is also 3mm, but i'm not using the table for anything really heavy or bending fixtures etc (have a very big and heavy woodworking bench for that) so really I just need a seperate table purely to weld things on.

I might even get some stainless flat stock and do part of the tabletop in stainless so i can avoid iron contamination from a mild steel tabletop

the 90 deg fixtures are a great help, would have taken me much longer to do it all without them, those things will see plenty of use lol.

thanks again
Dan

I did the top of my table with slats made of 2" angle back-to-back to form a T. they're super stiff and really easy to clamp to with tong vice grips or c-clamps.

I really like the idea of the angle iron "T". I think I'm gonna do that when I redo my welding table, cause I basically destroyed it beatin on it testin welds.

That 2x1/4" angle will make your table stronger than hell and will surely take anything you can through at it!

As for the stainless flat stock, I wonder if you couldnt just lay some sheet copper on top of some mild steel angle. Copper wont contaminate your stainless, or aluminum as far as I know. I just dont know if it would be any cheaper. You would just need a thin sheet, maybe some 22 guage or somethin to that effect. Just be sure you have it weighed down to your table so you get a good ground off it. Maybe some rivets?

I missed the stainless bit. if you're worried about contaminating aluminum, buy a sheet of 1/4" 6061 and use it for doing aluminum work. 1/4" is thick enough that you can drill and tap it to put in toggle clamps or what have you. it will certainly be cheaper than stainless or copper. I wouldn't recommend going any thinner than 16ga for copper or 20ga at the absolute thinnest for SS, or it will end up full of dents and (for stainless anyway) buckle and bulge under weld heat. the copper will be really soft, especially because you're going to keep annealing spots as you weld over them. it's also expensive. a 2'x4' sheet of .063" half-hard copper from online metals is $232.62. you get a 10% discount on that because it's over $100, but still... expensive.

2'x3' 20ga 316 SS is $70.89
16ga is $111.29

just for shits and giggles, 1/2" 316 is $1301.98

for alu, 1/4" is $131.79
1/8" is $66.13.

Wow I cant imagine sheet copper is that expensive. Copper prices are suppose to be going down!

copper is still almost always 4x the price of alu though. also, you probably wont notice a price change on anything but wiring in the near term. sheet and bar stock doesn't see nearly as much volume.

Yeah i reckon a bit of aluminium sheet might be the go instead of copper sheet or stainless flat bar. might just have to hunt for some offcut/scrap and screw it down to the steel frame.

On another note, I've noticed on one corner of the SHS frame, the top weld has cracked longitudinally, the whole length along (have not even used the table for anything yet and those welds were done last so havent twisted or distorted the frame or legs to get the bottom shelf frame in afterwards)

all 3 other corners have no cracks, and the fillet/outside corner welds on the same corner have no cracks either- just the butt weld on the top of the join. could this be a result of using 316L ss electrodes on mild steel?

I left these welds for last, basically tacked the frame together while clamped up, welded the outside corners alternating diagonally in sequence, then the inside corners alternating again, then i put the legs and bottom frame in and finally did all 4 of the topside butt welds and then flipped it over and did all 4 of the bottomside butt welds. maybe I should have done top then bottom for each corner, and alternated corners?

electrodes are 2.5mm (3/32 i think) and amperage around 85-90A DCEP

no preheat/post heat

another option would be to buy a nice 2x3' chunk of 1/2" mild steel, drill and tap the corners, and get some thinner sheets of alu, stainless, and copper and just bolt on what's most appropriate for what you're welding.(counter sink your sheets and use allen head bolts) as jody's video this week points out, the copper will (help) prevent arc strikes, too.


as far as that weld cracking... it shouldn't do that I have no experience with SS stick rod, so I'll let someone else chime in on that. my experience with SS TIG though says as long as you're shielded, you shouldn't have any cracking issues using stainless to weld mild together.

nother option would be to buy a nice 2x3' chunk of 1/2" mild steel, drill and tap the corners, and get some thinner sheets of alu, stainless, and copper and just bolt on what's most appropriate for what you're welding.(counter sink your sheets and use allen head bolts) as jody's video this week points out, the copper will (help) prevent arc strikes, too.

That was one of my main theories behind using copper. It wont contaminate anything you weld on, be it mild steel, stainless, or aluminum. Cost a bit more, but no changing sheets or worrying about welding your aluminum on a mild steel bench.

certainly not the worst ive seen and if it square your halfway there ,itll be alot easier getting practice now you have a table

This is a good example why I like plywood tables. They can be put up in a hurry in almost any configuration you need and when the current set up is done, you unscrew it and reconfigure it for the next job. Or just throw it away. You can also clamp wherever you need to and screw down fixtures anywhere you need them.

If I can't get MDO ply, I'll always use A/C because it's nice and flat. It also weighs a lot less than CDX which helps this old farts back out. Note that I always spray my plywood tables with a flame retardant called Fibre-Shield before I start to weld. I'll post their web site if anyone is interested.

On this table is the start of a couple of aluminium truss towers for a public tv station. They are 2'6" x 2'6" x 15' high and are made out of 1 and a 1/2 square tube for the base and 1 and a 1/4 schedule 40 pipe for the uprights. The centre spreaders are all notched to fit. Everything will mig welded with a 30a Spoolgun. You can see my (almost) brand new Millermatic 252 in the background.

Steve

A steel welding table is a basic necessity for any welder's workspace, since welding on a wooden surface can present a very real fire hazard. In addition, with a steel table, the welder's work clamp can be attached to it, and parts placed on the table will be electrically connected with the table's surface.

I have same thought as kermdawg. You provide good information.