another weld penetration thread

[MartZ0r]

hey chap's

got my regulator today and did a quick test on the 3mm 50x50 box i will be welding.

got a bit of scrap and set my wire speed near as, run a weld on some box section, max power setting and not getting any penetration sign on the reverse side. i didnt leave any gap on the joint. i also turned the wire down a bit and did a slower run, still nothing.

i will try a butt weld tomorrow and see how it goes. regulator is set to 12Lpm and the welder is a romarc 160 amp.

it's not blowing any fuses but when i press my torch trigger the light in my workshop spikes. maybe there is a lack of power? i do have it running from an extension.

il get some pics tomorrow, any suggestions on what to try other than a butt weld?

 

[gavuk]

Are you using 0.8 wire,loose the extension ,at least to proove welder is working correctly...I would stick with the butt weld for a test ,but you could practise fillets as well,see if you can still weld it with next setting up ,if you have one....

 

[MartZ0r]

Are you using 0.8 wire,loose the extension ,at least to proove welder is working correctly...I would stick with the butt weld for a test ,but you could practise fillets as well,see if you can still weld it with next setting up ,if you have one....

that was on the max setting. yes it's 0.8 wire. i will have to drag it down to the house tomorrow.

unfortunatly last winter the crabtree breaker got taken out so atm it's all runnng off a long fused extension till i fit another 32a box.

 

[gavuk]

The last few occasions,people have had problems ,its been wire diameter or power supply.....if you can run it direct ,it at least proves the welder is working correctly... please let us know how you get on and good luck

 

[MartZ0r]

just thought id runa few test with the meter.

Power setting voltages (not while welding)

1- 21.1v
2- 24.1v
3- 27.9v
4- 33.1v
5- 40.0v

Voltage before contactor 244v

voltage after contactor with trigger pressed (no while welding)

239-240v lowest setting, 4-5 setting Volts drop to 225v-230v and get very random. not sure if its just me but those voltages drop a fair bit really, i have even seen 220v.

high settings is when the workshop lights start to flicker.

 

[MartZ0r]

couldnt penetrate on a butt weld in my shed. so it's either just the limit of the welder or it is the extension. wil try it over the weekend hooked up to the house.

 

[MartZ0r]

few beads on some 3mm plate, flat. you could feel the weld on the other side, like a bump. seems like its nearly there. those runs were pulling the pool.

next power setting if it had one would do it. the little bit of spatter is from when i was from a run with the wire too high.

the beads are fairly wide as i was welding slow to try and penetrate it. a butt weld without any gap and no chamfer had the same penetration.. its not too bad really.


Looks like i will just have to chamfer the edges and corners of the box section then to make sure it gets it. what you guys recon?



Oh, and i was not able to take it to the house to test yet as its pi55ing it down.

 

[gavuk]

Try welding some joints Mart,butt,and fillet,with and without gaps,i still think a good power source will help, ....chuck in that 32amp supply again
Remember if you chamfer,you will need to check which sides to grind,depending on the joint you use,you may encounter welding the radiused edge of the box...

 

[Drains]

As Gav says, joints of different types with varying gaps.

With 3mm stock, leave a 1-2mm gap. You'll be surprised how low a power you can use and still get a good strong full-pen joint. With no gap at all you might struggle to do a good joint without either burning through or just building up on top. Not required on a fillet, mind you.

 

[MartZ0r]

i hear you guys.

i dont recon i will have troubble welding the edge of the box section where it butt's up. it will be more the fact the radius on the other section as i think it will take some heat to get through it.

if the weather picks up today i will take it down to the house and try it and do some butt welds and fillets.

Thanks for the advice fellas.

 

[MartZ0r]

MOD - lethal bodge removed following complaint

only issue is the penetration is a little hit or miss. fillet welds and also welding directly onto the radius of some 3mm box section sometimes penetrated and sometimes didnt. not quite sure why.. Same torch angle, technique and speed. i decided to help the welder out and take about 0.5-1mm off the radius of the stock.

it's the only way i can be sure it will fuse.

i have attached a few pictures. is it worth chamfering the edge of the stock that i have highlighted with a circle? i will bevel the edge that is circled in blue on the other picture.

 

[gavuk]

what are you making Mart?....I would gap the otherwise touching sides and go carefully on the radius join, sometimes though i only weld the radius sides,depends on the job...
I don't feel qualified to comment on your sparkey skills...

 

[MartZ0r]

what are you making Mart?....I would gap the otherwise touching sides and go carefully on the radius join, sometimes though i only weld the radius sides,depends on the job...
I don't feel qualified to comment on your sparkey skills...

hey bud.

Take a look in the projects section, i made a thread. i am making a squat cage for my home gym. so i am a bit picky on making sure it's strong

So you recon just gap it?

i am used to welding with big welders, been a little spoilt really using 300 amp migs. penetration with those things is very easy. i have never really had to do join prep other then if i was going to gring the welds down to hide them.

 

[Paul.]

For simple joints in lightweight box section you really shouldn't need any preparation, if you chamfer the end of the box section circled red you may find a problem with blowing through, or undercut, if you leave gaps to fill up there is a greater potential for distortion
These are on 40 x 40 x 3 shs, at about 150amps using .8 wire, just butted up nice tight joint

 

[MartZ0r]

hey paul

nice welds, are those just stringer(stright runs?) or? and did the weld appear on the inside you think or did you not worry about it too much?

i also thought it will probably blow though, being an edge anyway.

atm i am welding the box pulling the weld with a ever so slight angle on the torch. like i say sometimes it would penetrate and other times it wouldnt. if i could guarantee it would every time i wouldnt have grinded anything at all really.

 

[Drains]

MartZ0r, what do you mean by penetration? If you mean "getting weld to appear on the other side of the steel", then you may be getting the wrong end of the stick. On a butt weld you want the weld to go through to the root of the joint, and on a fillet weld... well it's the same thing, but essentially, the weld should go into the corner of the fillet. Additionally you want side-wall fusion, as without that, there is no weld at all.

 

[MartZ0r]

MartZ0r, what do you mean by penetration? If you mean "getting weld to appear on the other side of the steel", then you may be getting the wrong end of the stick. On a butt weld you want the weld to go through to the root of the joint, and on a fillet weld... well it's the same thing, but essentially, the weld should go into the corner of the fillet. Additionally you want side-wall fusion, as without that, there is no weld at all.

looks like i am then, i have always tried to get some of the weld to appear on the inside corners of the stock, even when making things at work. like i say with the 300 amp migs it's never been an issue.

so really that radius is just like welding a normal fillet (like just sidewall weld)? and there is actually no need to have slight blow through on the inside of the radiused part? the welds are very well fused just couldnt get any to appear inside. but looks like iv always been mis understood concerning that then

 

[Paul.]

Yes just stringers no weave required here, you would be better off pushing the torch, just slope it back about 15deg so you can see where you're going, if your looking for penetration right through the full 3mm thickness its not necessary, on fillets all you want is to penetrate the corner

Edit: like the picture that drains has posted

 

[MartZ0r]

Yep, im with you now. yeah i have always had the wrong end of the stick then concerning that.

so really as long as its not a cold weld and it bites into the steel, it's fine then going by that?

 

[MartZ0r]

So really all the tests i did today were fine anyway and i was making it harder for myself.

now i know i dont have to penetrate it like i was trying to i will push instead. Pulling i was able to get more heat into at the angle i was working. it's harder to see where your going though =)

guy's you have saved me a lot of stress!