mig and flux core tips and techniques, equipment, filler metal
newbie_welder123
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Hi All!

I'm a new welder - I have a super inexpensive wire welder from amazon, and am working on building some chairs out of 16 ga 1" square steel tubing/

On the butt welds (t-shaped), I am doing "ok", but I have 2 x 45* miter welds on each chair (where the arm meets the leg), and I can't stop blowing through the gap. Also, i'm using a metal cut-off saw that has a 45* setting, but the cuts are still such that the outside of the miter has a 1/16" gap at 90*, and I can't figure out how to weld it "closed."

I'm using .030 wire, but just ran out of a spool, so could get a different size if y'all think that would be better.

My welder has 4 power settings (Min & Max x 1 & 2....fancy!), and has a wire feed speed knob with 1-10.

I'm prepping the edges by flap sanding a small bevel into the corner sections, and wire wheeling off all the mill scale around the weld. I've found that at the power "Min x 2" (basically 2/4) + wire feed in the 6-8/10 range, I can get a decent looking weld on the butt sections, but here's a picture of the miter welds....prepare yourself for horror!

Any ideas or feedback VERY much appreciated, thanks!
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Don't be too hard on yourself. The reason why are able to weld the tee joints but not the butts is because there is heaps more material to both back up your weld and carry away the heat. It's not easy for anyone to butt weld 1.2mm or 16g steel regardless of skill. It just wants to burn through. The easiest way to get by is to do small spots, some call triggering or stop start, to do a spot of weld, stop, let it cool, move, and repeat. That's slow but it gets the result you need. Another way is to tack a piece of material inside the tube to back up the weld. It'll become part of the joint and stay in there. That gives the effect of welding twice the thickness of your material and eliminating burn through.
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Check your voltage and wire feed speed. It looks like you are running hot and you are going to want to run as cold as you can. Are you running innershield? No need to prep/bevel the joints on that thickness since you will get full penetration (in fact, you're better off not to bevel them so that you have more base material in there).Here is a video of manual pulse welding. This guy is pulsing to fill a gap, but the same can be done for thin material.
tweake
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newbie_welder123 wrote:Hi All!

I'm a new welder - I have a super inexpensive wire welder from amazon, ...........
On the butt welds (t-shaped), I am doing "ok", .......

My welder has 4 power settings (Min & Max x 1 & 2....fancy!), and has a wire feed speed knob with 1-10.
do you have a pic of your good welds?
is this bare wire or flux core?

personally i would throw that welder in the bin and go get something at least half decent.
theres plenty decent migs that have variable voltage settings and even inductance.
even a cheap inverter stick welder will weld that tube fine.
tweak it until it breaks
noddybrian
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That thickness is hard to weld even if experienced with the gear your using so no disrespect on your first try - I have helped several people who have similar if not the same welder bought from a supermarket / big box store & they mostly had the same problem - the wire speed will not go low enough so the wire is pushing the limit of burn off or stubbing all the time - I would try again with the wire speed as low as it goes & only increase in small amounts if the wire burns back too fast or back to the tip - allow a fair ( 3/4" approx ) stick out as the wire needs time / space to heat the flux to operating temp = I think the 2nd of 4 voltage setting is about right & they mostly have insufficient power on the lowest to run .9mm / .030" wire - on some models the makers added a " ballast " resistor across the wire speed pot to give it in theory finer control over the speed - on some this actually won't allow the speed to go low enough for the voltage resulting in a weld much like yours - I have snipped these off to give full speed control on some & when I had time / stock resistors with me change them out to allow slower feeds - it maybe the case with yours that you need to do the same - they are a tough first welder to learn on with thin metal - they work just fine on 1/8" - the wire itself varies & the roll supplied with it is often terrible - I'd try getting some quality wire first then play with wire speed - good luck with it - hope your chair project comes out well even if it needs a little grinding - don't try any trailer hitches just yet !
newbie_welder123
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weldin mike 27 wrote:Don't be too hard on yourself. The reason why are able to weld the tee joints but not the butts is because there is heaps more material to both back up your weld and carry away the heat. It's not easy for anyone to butt weld 1.2mm or 16g steel regardless of skill. It just wants to burn through. The easiest way to get by is to do small spots, some call triggering or stop start, to do a spot of weld, stop, let it cool, move, and repeat. That's slow but it gets the result you need. Another way is to tack a piece of material inside the tube to back up the weld. It'll become part of the joint and stay in there. That gives the effect of welding twice the thickness of your material and eliminating burn through.
Thanks Mike! Appreciate the confidence boost :) I tried to tack some material behind, but because it's a miter made from 2 pieces of tube (intended to close the corner for the arm rest x leg), it was hard (impossible for me) to get something to "stay" back there. I *did* go much slower and built up - and that seemed to work! Lot's of grinding, but making progress. I also ran out of wire right as I posted this, so I jumped up to a .035" wire which seemed to help too. Thanks for the advice!


noddybrian wrote:That thickness is hard to weld even if experienced with the gear your using so no disrespect on your first try - I have helped several people who have similar if not the same welder bought from a supermarket / big box store & they mostly had the same problem - the wire speed will not go low enough so the wire is pushing the limit of burn off or stubbing all the time - I would try again with the wire speed as low as it goes & only increase in small amounts if the wire burns back too fast or back to the tip - allow a fair ( 3/4" approx ) stick out as the wire needs time / space to heat the flux to operating temp = I think the 2nd of 4 voltage setting is about right & they mostly have insufficient power on the lowest to run .9mm / .030" wire - on some models the makers added a " ballast " resistor across the wire speed pot to give it in theory finer control over the speed - on some this actually won't allow the speed to go low enough for the voltage resulting in a weld much like yours - I have snipped these off to give full speed control on some & when I had time / stock resistors with me change them out to allow slower feeds - it maybe the case with yours that you need to do the same - they are a tough first welder to learn on with thin metal - they work just fine on 1/8" - the wire itself varies & the roll supplied with it is often terrible - I'd try getting some quality wire first then play with wire speed - good luck with it - hope your chair project comes out well even if it needs a little grinding - don't try any trailer hitches just yet !
Thanks NoddyBrian! What's weird is - it seems like I get less burn-through with higher wire speed. This seemed counter intuitive to me, but I kinda assumed that it was because the slower wire was building up heat in one spot too much? Should I be using lower wire feed speed + faster travel maybe? Or maybe this "made in china" welder has the wire speed dial backwards? :lol: I am using Lincoln wire from a big box store - I tossed the spool that came with the welder already LOL!
tweake wrote:
newbie_welder123 wrote:Hi All!

I'm a new welder - I have a super inexpensive wire welder from amazon, ...........
On the butt welds (t-shaped), I am doing "ok", .......

My welder has 4 power settings (Min & Max x 1 & 2....fancy!), and has a wire feed speed knob with 1-10.
do you have a pic of your good welds?
is this bare wire or flux core?

personally i would throw that welder in the bin and go get something at least half decent.
theres plenty decent migs that have variable voltage settings and even inductance.
even a cheap inverter stick welder will weld that tube fine.
Thanks for the feedback tweake! I'll attach some pictures of the "better" welds here - still pretty ugly, but I have lots of grinding disks and flap sanders, which can fix anything, right?!?! 8-) I may well upgrade to a better welder if I am doing more projects, for now, looking to "do more with less" - and both for the $ and the space, can't justify another tool in the shop on the metalworking side :)
WirelessG wrote:Check your voltage and wire feed speed. It looks like you are running hot and you are going to want to run as cold as you can. Are you running innershield? No need to prep/bevel the joints on that thickness since you will get full penetration (in fact, you're better off not to bevel them so that you have more base material in there).Here is a video of manual pulse welding. This guy is pulsing to fill a gap, but the same can be done for thin material.

Thanks WirelessG - I am assuming you're saying it's running hot because of the black slag? Good feedback not to bevel the edge, i'll try that next time around. it feels like beveling the edge *does* create a a larger gap to fill - which makes my blow through way worse. Thanks for this video - logistical question - I can't "tack" between the spots using the wire, because there's more space than my wire between the gaps - should I be starting on the "face" of one of the pieces and dragging across? Do I wait for the weld to puddle before pulling? It seems hard to time it so that I get heat, but not blow through (which sounds like it's expected for my welder + material).


Thanks everyone for the help!!!
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BillE.Dee
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Hi Newbie and welcome. I did read where you thought the wire speed control is working backwards - is the wire speed noticeable at each extreme of the control for you to tell if it is working backwards? One thing for sure is Never say Never. Also, when I started my journey, I started on heavier material to get a feel for the machine and experiment with the controls. I do know that there are lots of folks that will help. Best of luck and keep us posted as to your progress.

Bill
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All good mate, what I mean is that you tack a piece in and then slide the other part on. I'll make up a example for you.
tweake
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newbie_welder123 wrote:
Thanks for the feedback tweake! I'll attach some pictures of the "better" welds here - still pretty ugly, but I have lots of grinding disks and flap sanders, which can fix anything, right?!?! 8-) I may well upgrade to a better welder if I am doing more projects, for now, looking to "do more with less" - and both for the $ and the space, can't justify another tool in the shop on the metalworking side :)
have you got those pics of the "better" welds?

the grinder may pretty the welds up but thats pointless if the welds break because of the issues.
i would not want someone to sit on the chair and have it fail.
have you tested any of your welds?
i was gobsmacked when i first tested my early mig welds and they failed. even when they look good they can be bad.
one of the traps with mig. its a real eye opener when your good welds don't hold up, but its very good to learn from.

i think the best approach is to make sure you can weld good enough before you start making things that could hurt someone if its fails.
tweak it until it breaks
homeboy
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One thing that might help is drill a small hole,1/4 " or a bit smaller a bit past the miter on each corner piece. slide a piece of 1/8 flat that will fit width of the tube inside and clamp it tight up against the hole. leave it sticking out no further than will allow the other corner piece to slide over it. Plug weld the clamped piece inside the tube first thru the drilled hole then slide the other miter in place and plug weld it also. Do the same for both sides. This will give you more interior reinforcement in the corner and less chance of blowing thru the thin tubing. Get some scrap and play around for a bit. Flux core can be a a bit tricky to get on to but it is a good penetrating weld. Grind as required!
newbie_welder123
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tweake wrote:
newbie_welder123 wrote:
Thanks for the feedback tweake! I'll attach some pictures of the "better" welds here - still pretty ugly, but I have lots of grinding disks and flap sanders, which can fix anything, right?!?! 8-) I may well upgrade to a better welder if I am doing more projects, for now, looking to "do more with less" - and both for the $ and the space, can't justify another tool in the shop on the metalworking side :)
have you got those pics of the "better" welds?

the grinder may pretty the welds up but thats pointless if the welds break because of the issues.
i would not want someone to sit on the chair and have it fail.
have you tested any of your welds?
i was gobsmacked when i first tested my early mig welds and they failed. even when they look good they can be bad.
one of the traps with mig. its a real eye opener when your good welds don't hold up, but its very good to learn from.

i think the best approach is to make sure you can weld good enough before you start making things that could hurt someone if its fails.
Hi Tweake! I'm attaching some photos of the welds I felt better about, in addition to the ground down versions attached to my last post. In terms of testing it - I am also attaching a photo of the first chair in semi-done format. I plan to put wood planks across the seat and back, and paint the steel black - but you can see the form. I have put a scrap board across the seating area and sat (with feet off the ground) with no movement/stress noticeable in the chair. I weight 220 #, so not an insignificant strain. I've pulled at the miter joints with some elbow grease and the don't move. How should I test the welds, given my situation?
homeboy wrote:One thing that might help is drill a small hole,1/4 " or a bit smaller a bit past the miter on each corner piece. slide a piece of 1/8 flat that will fit width of the tube inside and clamp it tight up against the hole. leave it sticking out no further than will allow the other corner piece to slide over it. Plug weld the clamped piece inside the tube first thru the drilled hole then slide the other miter in place and plug weld it also. Do the same for both sides. This will give you more interior reinforcement in the corner and less chance of blowing thru the thin tubing. Get some scrap and play around for a bit. Flux core can be a a bit tricky to get on to but it is a good penetrating weld. Grind as required!
Homeboy - this makes SO MUCH sense - thank you! I was totally at a loss for how to get a piece to stay inside the miter - and tack welding from the edge created weld spatter that stopped my first attempt from fitting together! Will try this on the next chair for sure!!! Thanks!

I know I should practice on some scrap, but when I get in the garage and get the welder setup....i'm just so darned excited to make progress on my project!!!
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newbie_welder123
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BillE.Dee wrote:Hi Newbie and welcome. I did read where you thought the wire speed control is working backwards - is the wire speed noticeable at each extreme of the control for you to tell if it is working backwards? One thing for sure is Never say Never. Also, when I started my journey, I started on heavier material to get a feel for the machine and experiment with the controls. I do know that there are lots of folks that will help. Best of luck and keep us posted as to your progress.

Bill

Hi Bill,

I actually tested today (counting off 3 seconds while pulling the trigger, not connected to a grounded surface) - and the speed matches the dial (fastest shot out appx 5 times as much wire as slowest).

But I am still experiencing the same thing - at a low speed, I burn through WAY faster than at the faster speed. any idea why? :oops:
tweake
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newbie_welder123 wrote:
BillE.Dee wrote:Hi Newbie and welcome. I did read where you thought the wire speed control is working backwards - is the wire speed noticeable at each extreme of the control for you to tell if it is working backwards? One thing for sure is Never say Never. Also, when I started my journey, I started on heavier material to get a feel for the machine and experiment with the controls. I do know that there are lots of folks that will help. Best of luck and keep us posted as to your progress.

Bill

Hi Bill,

I actually tested today (counting off 3 seconds while pulling the trigger, not connected to a grounded surface) - and the speed matches the dial (fastest shot out appx 5 times as much wire as slowest).

But I am still experiencing the same thing - at a low speed, I burn through WAY faster than at the faster speed. any idea why? :oops:
i suspect its because your travel speed is slower. slower travel speed means there is more time for heat to accumulate in the metal and it over heats it. so crank the heat up and go faster.
flux cores can be unforgiving. you need the right amps, volts and stickout. sometimes it has to be absolutely bang on to weld good.

its hard to tell with your welds due to the grinding, but it looks fairly horrible. sorry but i'm honest.
are you seeing the puddle?
if you can't see the puddle your screwed. set your helmet to a better setting, get yourself into a position where you can see the puddle.
the welds look all over the place like your wobbling around. get some support, lean on something. be steady use two hands. often rest on elbow and use that hand to steady the torch with as well.
if your nice and smooth but the arc is stop/starting all the time then you need to check the setup.
runs some beads on some scrap, get it dialed in perfectly. there is a lot of things to adjust with mig.

testing. weld a small T joint, put it in the vice and break it. see where it breaks. post pics on here would be good.
i've done perfect looking welds only to have it pop off like it was just sitting there.

you should not need any backing inside the tube. it should be easily within your welders ability. you could even stick weld that easy enough.
tweak it until it breaks
newbie_welder123
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tweake wrote:
newbie_welder123 wrote:
BillE.Dee wrote:Hi Newbie and welcome. I did read where you thought the wire speed control is working backwards - is the wire speed noticeable at each extreme of the control for you to tell if it is working backwards? One thing for sure is Never say Never. Also, when I started my journey, I started on heavier material to get a feel for the machine and experiment with the controls. I do know that there are lots of folks that will help. Best of luck and keep us posted as to your progress.

Bill

Hi Bill,

I actually tested today (counting off 3 seconds while pulling the trigger, not connected to a grounded surface) - and the speed matches the dial (fastest shot out appx 5 times as much wire as slowest).

But I am still experiencing the same thing - at a low speed, I burn through WAY faster than at the faster speed. any idea why? :oops:
i suspect its because your travel speed is slower. slower travel speed means there is more time for heat to accumulate in the metal and it over heats it. so crank the heat up and go faster.
flux cores can be unforgiving. you need the right amps, volts and stickout. sometimes it has to be absolutely bang on to weld good.

its hard to tell with your welds due to the grinding, but it looks fairly horrible. sorry but i'm honest.
are you seeing the puddle?
if you can't see the puddle your screwed. set your helmet to a better setting, get yourself into a position where you can see the puddle.
the welds look all over the place like your wobbling around. get some support, lean on something. be steady use two hands. often rest on elbow and use that hand to steady the torch with as well.
if your nice and smooth but the arc is stop/starting all the time then you need to check the setup.
runs some beads on some scrap, get it dialed in perfectly. there is a lot of things to adjust with mig.

testing. weld a small T joint, put it in the vice and break it. see where it breaks. post pics on here would be good.
i've done perfect looking welds only to have it pop off like it was just sitting there.

you should not need any backing inside the tube. it should be easily within your welders ability. you could even stick weld that easy enough.

Thanks Tweake, appreciate the details - supporting my arm has not been a focus for me - good call out there!

If I want to fix previous welds - can I just go over the ground down welds, or do I need to break, grind clean and re-weld?

In terms of the puddle, some of the time I *do* see a puddle, but often right after that I burn through :( It's like it takes the same amount of time to puddle as it does to melt the steel in that spot....

I'll try beads on a flat piece, to work on the settings. Sounds like setting up, wire speed down, and move my gun more quickly as a starting point....

Thanks!
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Sell that junk/throw it away and get yourself a decent MIG welder! Even if you only run gas-less flux-core, having wirefeed speed and voltage controls with infinite adjustability on a good MIG welder will go a loooooooong ways to you developing your welding skill! In the time you spend trying to figure out the "optimum" settings with that machine, you could already have started to get good looking/performing welds with a good machine.
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[/quote]Thanks WirelessG - I am assuming you're saying it's running hot because of the black slag? Good feedback not to bevel the edge, i'll try that next time around. it feels like beveling the edge *does* create a a larger gap to fill - which makes my blow through way worse. Thanks for this video - logistical question - I can't "tack" between the spots using the wire, because there's more space than my wire between the gaps - should I be starting on the "face" of one of the pieces and dragging across? Do I wait for the weld to puddle before pulling? It seems hard to time it so that I get heat, but not blow through (which sounds like it's expected for my welder + material).[/quote]

You are blowing through because of the concentration of heat in and the material (and the time that heat is concentrated). Yes weld a pulse tack on one side and then on the other side of the joint and keep doing this until the two sets of tacks are joined and then move to another location. Wait for the weld to solidify before pulsing on it again. You can also put a piece of backing bar inside the joint to catch the weld as you lay it in. You won't have any backing at the corners, unless you spend a lot of time fitting the backing, but you can always pulse the corners.

I originally asked if the wire was flux core or not and I'm not sure that was ever answered. What is the spec on the wire you are using? Are you using gas shielding (i.e. is a bottle of compressed gas connected to the welder)? It almost looks to me like you are using outershield wire with no shielding gas because of the soot, spatter, and appearance of the bead.


Attached is a sketch of the cross section of a few joints. This may be a little too technical for your stage of knowledge, but I thought it might help. AWS (American Welding Society) is the government body for structural welding (kinda like a building code). They have a number of prequalified weld details, which means that you need not build and weld and mock-up of these joints for testing in order to prove their suitability. The first two joints are prequalified butt joints that will achieve full penetration (full fusion of the joint) provided that the plate thickness root opening (0" or 1/8") are maintained along with other technical variables. The purpose for showing you these two joints is to demonstrate that thin materials will fully fuse together without beveling. The 3rd joint is 1" thick, with a 1/8" root opening and clearly it is not fully fused. If you wanted to full fuse the material, you would have to bevel one side (or both sides) and build up the weld with multiple passes. The bevel that I show does not run full depth of the joint. I left a "land" of bout 1/8" and that is there to avoid blowing through the material.

I would suggest you go to your local weld store (not Home Depot or tractor supply, but a Praxair or Air Liquide and ask the guy if he knows any welders that can help you learn. You might just find someone who will charge $20/hr or $50/hr and after a couple hours you will be a lot better off. Once you feel more comfortable, you can start to look at and learn from the videos on the weldingtipsandtricks youtube channel. But you really should have someone around to look over your shoulder and guide you.

Don't throw your welder out just yet. It may be a cheap on, but at this stage it probably has more to do with operator error than the quality of the equipment.

REMEMBER - Tell us what kind of wire are you using, what your voltage and wire speed are, and are you running shielding gas.
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tweake
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newbie_welder123 wrote: Thanks Tweake, appreciate the details - supporting my arm has not been a focus for me - good call out there!

If I want to fix previous welds - can I just go over the ground down welds, or do I need to break, grind clean and re-weld?

In terms of the puddle, some of the time I *do* see a puddle, but often right after that I burn through :( It's like it takes the same amount of time to puddle as it does to melt the steel in that spot....

I'll try beads on a flat piece, to work on the settings. Sounds like setting up, wire speed down, and move my gun more quickly as a starting point....

Thanks!
fixing previous welds, i would be inclined to cut it all apart and redo. however first thing is to make a weld and break it. see where it fails. that will tell you if you should trust your welding or not.
even pro welders will do that, make a test weld and check it. make sure their welder is doing what it should be doing before they start on the job.

its a lot easier to have someone just look over your shoulder but i know thats not always possible. i'm not sure if your not seeing the puddle until its to big, or your not running hot enough and your waiting for the puddle to form, which overheats the metal.
run it hot and move.
i would practise on some thick steel first. make sure you can see the puddle, feed the puddle from the front edge, and drag it along keeping the puddle the same width. with that size flux core the bead should be quite narrow.
this is why i recommend to learn stick welding first. its only a tad harder (but simpler) and it teaches you all the important things.
tweak it until it breaks
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