Welding Axle Brackets

[dan.taylor.1]

Bill that was my thinking. Will decide after I try another mig run tomorrow night/Wednesday. As I've never run a bead that bad before, I'm almost embarrassed to post a pic eligible it weren't for the fact I'm sure someone will have some advice and I'd learn from it!

 

[dan.taylor.1]

Kent, the axle is new, and the plate will be too, can stick it on my tressles and move it to whatever position so not a problem in that respect. My 200a runs 4mm brilliantly, it'll run 5mm too but I've only run a few a mate gave me.

Oh and the chassis is most definitely not new!! It's older than me but I know what you mean about non weldable stuff. I won't be welding the chassis anyway as the axle is entirely bolted on, the welding it of the new plates the bolts go through onto the axle as it's just a plain 70mm square atm.

 

[Bill Edwards]

I wouldn't go to 5mm; there's a difference between running them and running them properly.
You see 150a welders claiming to run 4mm, but it feels far safer to use 130a with a 3.2mm that you know is hot enough and getting in there.

I'd be using 4mm rods if that's what I had to hand with a 200a machine.
But I'd be perfectly happy using 3.2mm rods at the right power to do this job. I don't know the weight of this tanker, but the beauty of MMA is that even with low power you can make it as strong as you need with multi passes without any risk of cold welds.

 

[Kent]

Kent, the axle is new, and the plate will be too, can stick it on my tressles and move it to whatever position so not a problem in that respect. My 200a runs 4mm brilliantly, it'll run 5mm too but I've only run a few a mate gave me.

Oh and the chassis is most definitely not new!! It's older than me but I know what you mean about non weldable stuff. I won't be welding the chassis anyway as the axle is entirely bolted on, the welding it of the new plates the bolts go through onto the axle as it's just a plain 70mm square atm.

Ok run or run well? 5mm 7018 is going to be cold on a 200 amp set, 4mm ? depends. I am not good at following this sort of stuff by description sorry, preferring to see it or a proper drawing. I should go for a smaller rod but run hot than a bigger rod cold, you can always put the extra beads in. A 3.2mm 7018 could run in the range say 100-140 amp for instance but I shouldn't try this job at the cold end of any rods range.

My guess is that chassis is like the average then

 

[dan.taylor.1]

Yeah It ran the 5mm bead was nice, it passed me beating the hell outa it with a bfh. 4mm run perfect at 150a so I've 50a left to run it up.

I see what you mean about running smaller rods hot rather than big rods cold. Ill be honest I reckon this set rates itself lower than it runs!

 

[dan.taylor.1]

New axle, 70mm square with big round corners!



Old axle at the top of pic with plate welded on, single bead all the way round the plate.



Vertical plate again welded all the way round with one bead/pass.



From the other side of the plate.

 

[dan.taylor.1]

Single mig pass in spray ~24v and 7.5/10 wire feed (not sure what that equates to in m/min) you can see the porosity a bit even though its blurry!



Porosity on the weld, but the bead on top is spot on done not 10 secs after the bottom one!



Etched mma with the mig run below it.



Other half of the mma (cut the piece in half, polished and etched with rust remover).



Porosity in mig runs.

 

[Kent]

Yep about average that chassis, hellishly corrosive stuff is slurry

 

[dan.taylor.1]

Yep. I will point out most of what looks like corrosion is dried slurry as it broke before we finished using it (1 load before typically!) So it never got washed!

To be honest only one side is bad as it gets splashed more due to the inlet stopping the other side getting any! It's solid considering its older than I am!

 

[Rudi McAnichal]

Do the welds really need to be very strong?

The horizontal plates appear to be carrying all the weight of the tank at the rear (presumably there are other attachments onto the front end of the chassis).

Notches in the vertical plates seem to be taking all the fore-and-aft forces, so the welds between vertical plates and axle only need to resist sideways forces (cornering and hillside work).

Welds between horizontal plates and axle stop the tank from sliding on the chassis under braking, and might be quite highly stressed. I would be inclined to weld blocks onto the underside of the horizontal plates, to resist the braking forces. Making those welds on fairly small pieces of 12mm plate, before fitting them up to the axle, should be well within the capabilities of your equipment.

 

[dan.taylor.1]

Rudi, yes that would work but they'd have to be trebled up as the radius on the axle is more than 12mm!!

And no the tubs weight is mostly taken by the chassis, a bit of it is on the axle via the plates.

 

[dan.taylor.1]

Well I got it all welded up this afternoon after spending all morning getting 12 m20 bolts out of the old one, had to cut the heads off a bit at a time as space is so limited!

Went with the mig on 24v and 7.5/10 wire feed same as those tests I did, 6 passes including root and I'm well happy with them.



Brake ram bracket welded on in the centre, had to faf with this as its meant to push forward from above but the tanks in the way so it pushes back from below now! Also had to make a mounting for the return spring, cue a handy bit of 14mm that came as a transit pin from our new washing machine!



Everything got a nice big pile of welds!



All done and primed so it wont rust in the rain were getting overnight!

I'm well chuffed my mig saved me again, also the mag drill and plasma saved a lot of time and mucking about drilling holes and cutting plates out!

 

[balmerchris]

Nice job there, looks more than strong enough.

 

[Kent]

looks presentable to me

 

[Bede]

Those look fairly decent for a 250 amp set.

My Nital arrived yesterday so I've etched the sample I did from earlier in this thread. This is the result of a 230 amp mig on full setting welding 15mm plate, as described in page 1. The penetration isn't bad actually. From this, I'd say your welds on that axle should be fine.

I'm currently making 2-off 24 tonne lifting beams so I'm gonna produce a sample from the 40mm plate lifting eye welding and etch that to see the difference between a little 230 amp penetration and 300 or so amps on a 7 run 14mm fillet. I'll post pics to compare next week.

 

[dan.taylor.1]

Be interested to see that Bede

 

[Bede]

Started it this afternoon. Assembled the 3 lifting points and stuck a 6mm root down.

 

[Bede]

Those pics look like I've put down really jumpy weaves forward. I can assure you that's not the case - it's highly reflective tiny ridges from very subtle torch movement bouncing light off. Industrial lighting and iphone cameras aren't the best!

 

[dan.taylor.1]

How do you go about testing that beam Bede?

 

[Bede]

It'll be MPI'd upon completion.

Before I weld it proper I'll do a test piece to the same spec and etch it to have a butcher's then provide that with the job if the client wants it - they're sorting the testing out.