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Welding advice


HoSS

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I need to weld a winch tray onto my chassis (this is not on my LR, but my C303)

I have a MIG set and my horizontal welding ability is ok. But this tray will need to be welded from below in a right angle joint, and my upside down welding is poor.

a) Can anyone give me some tips to improve my upside down MIG welding

or b) If i got a more experienced welder to come and do it, would MIG still be ok, or should i be asking for another technology (TIG?)

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I need to weld a winch tray onto my chassis (this is not on my LR, but my C303)

I have a MIG set and my horizontal welding ability is ok. But this tray will need to be welded from below in a right angle joint, and my upside down welding is poor.

a) Can anyone give me some tips to improve my upside down MIG welding

or b) If i got a more experienced welder to come and do it, would MIG still be ok, or should i be asking for another technology (TIG?)

Practice first on a scrap piece and have a go mate. You can always grind it off and go again if its really bad.

Personally I prefer an inverter welder as they are pretty handy in tight spaces. Our crane monkeys use them all the time as they are light and have a shoulder strap.

Barry

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Give yourself a GOOD escape route! I spent 20 minutes digging a chunk of weld out of my sternum earlier this year, as, being in a hurry I was sort of trapped under the rear axle when gravity took over the weld pool. Another way is to practise welding wit one arm whilst lying on your side - works for me and I only set fire to one arm!

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up the wire feed speed and don't loiter, try and get both pieces cleans as you can with a slight gap. Use leather sleeves ear defs and an apron over your nether regions

Best advice to give any novice welder :):):)

Practice loads before you do it for real, I know it helped me to spend a week welding old scrap together that was just hanging over the edge of the bench whilst I was on my knees underneath.

Just wondering out loud here but would it not be easier to weld the tray onto thick angle irons and then drill and bolt to chassis using crush tubes, or was that idea scrapped for various other reasons?

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like they have said, Fast wire speed, Fast runs, more gas than usual, and personally, i would (welding in "C" style zig zag patterns) do 2 or 3 C's then stop, let it cool, less chance for excess droopage and drippage,

make sure there is a fair amount of power so it penetrates properly, being shorter bursts it is important. especially welding on a winch tray. if possible weld both sides of the seam and dont leave a mm unwelded!

some say an inch of weld can hold a ton,

assume it can only hold a jelly bean.

after you finish, anchor it down and winch against something solid. making sure you strain it more than you think you ever normally would. (without buggering the winch).

only then you can presume that it MAY be strong enough for use out in public places.

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Thanks all of you for the advice.

The front of the winch tray overhangs the cross-member so i will put in some triangular fillets which i can weld to the tray before it goes on, and then do the vertical after.

And the 2 rear winch bolts will go through the x-member as well. It wont be going anywhere.

I would never just weld a winch tray to the chassis.......

Saw one rip out and take a lads knee cap straight off once!

I can still hear the screaming...

Did i say anywhere it would JUST be welded...? No.

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You can also plug weld to increase the strength and you might be able to do that in areas that don't require upside-down welding.

They say that an inch (2.54cm) of good weld can hold a 1000kg, so if you are short of inches on the joint you are planning to weld then plug welding can help.
It can also spread the connection load to other area of metal instead of concentrating it in one spot.

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1 inch of weld can hold a ton, but they never mention the strength of the metal to which its welded......

This is a very good point.

Do any winch suppliers give the steel grade in their spec sheets? Also I have never been able to find a grade for Defender chassis or bumper steel used by LR, or aftermarket suppliers.

Barry

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A guess, and its only a guess, is that they use CR4, Cold Reformed steel, which I understand is designed for the fabrication industry for bending, but my only experience of it is in that that's what comes from my laser cutter for the bits of plate-work for the steam engine I'm building, I'm not a sheet metal worker!

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CR4 is a redundant spec now, as is HR4. Unless it is 3.2mm or thinner it is very unlikely to be a Cold Reduced sheet grade. Its much more likely to be a Hot Rolled (HR) steel grade.

The problem is that HR grades cover a multitude of different structural( tensile) strengths.

Personally I would like to know that a replacement chassis or a winch is up to the job.

I suspect that aftermarket chassis suppliers might already be beefing up the steel thickness to compensate, which is a bit of an arse about face way of doing it, when its possible to source much stronger steel than anything available in the past.

On the good side thicker steel takes longer to rust away!

Sorry to have moved off the topic a bit.

Barry

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Here at Terex we specify mild steel to BS EN 10025 5275 for our laser cut and profiled fabs.

all we do is specify that and the thickness required.

That's more like a proper grade Discomikey. Its the Euronorm standardised Hot Rolled structural plate specification.

I think its S275 which is the Tensile in Newtons/mm2.

Be interesting to know how LR chassis compare.

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That's more like a proper grade Discomikey. Its the Euronorm standardised Hot Rolled structural plate specification.

I think its S275 which is the Tensile in Newtons/mm2.

Be interesting to know how LR chassis compare.

And Barry enters full bore anorak mode :moglite::moglite::moglite:

I wish I could actually sip a beer with you one day man :lol:

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Well it wasn't welded properly then. Or the parent metal was dodgey. No reason that a winch mount can't be just welded on.

Thank god, someone beat me to it!

The request was for welding tips (which I feel have been adequately covered), not design critique.

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