t.j.
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 posted on 25/5/06 at 09:24 AM |
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welding and cracks?
Q. I welded some of the Fe360 2mm with a mig 130A. the weld looks ok.
Then a used a small grinder to flatten the surface. I noticed some small cracks.
What did i wrong?? Or is it normal to have cracks at the zero-surface?
grzt
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MikeR
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| posted on 25/5/06 at 10:02 AM |
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whats fe360 ?
cast iron ?
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t.j.
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| posted on 25/5/06 at 10:20 AM |
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quote:
Originally posted by MikeR
whats fe360 ?
cast iron ?
Fe360= St37-2 = S235JR ,
don't know any GB-standards
[Edited on 25/5/06 by t.j.]
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tks
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| posted on 25/5/06 at 10:54 AM |
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Fe360
Is the normal cheapest iron.
Norm: EN 10027-1 its S235
Norm: EU 27-74 Fe360
To make a weld that won´t go away when you use the grinder don´t apply material only heat up the union and melt it together.
Tks
The above comments are always meant to be from the above persons perspective.
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RazMan
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| posted on 25/5/06 at 11:39 AM |
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quote:
Originally posted by tks
To make a weld that won´t go away when you use the grinder don´t apply material only heat up the union and melt it together.
Tks
That's a bit difficult with a mig 
Cheers,
Raz
When thinking outside the box doesn't work any more, it's time to build a new box
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t.j.
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| posted on 25/5/06 at 12:01 PM |
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quote:
Originally posted by tks
Is the normal cheapest iron.
Norm: EN 10027-1 its S235
Norm: EU 27-74 Fe360
To make a weld that won´t go away when you use the grinder don´t apply material only heat up the union and melt it together.
Tks
?????
Ok, with other words: welding with acityleen would be better? Takes more time and skills though.
So is it normal by mig-welding that there are cracks in de weld or not?? If not, how can i avoid it?
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Peteff
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| posted on 25/5/06 at 12:38 PM |
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Are they cracks or are you undercutting the weld? You shouldn't need to grind that much of the weld away. Try not holding the gun so steep when
you weld.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
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NS Dev
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| posted on 25/5/06 at 02:14 PM |
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more to the point why are you welding it??
Not something I would choose to weld
Retro RWD is the way forward...........automotive fabrication, car restoration, sheetmetal work, engine conversion
retro car restoration and tuning
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tks
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| posted on 25/5/06 at 04:19 PM |
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oooopsss
sorry thought he mentioned TIG.
When welding MIG you should try to create a flat weld, settings needed are hot,
sow high amps and high flow, high speed of movement.
altough its difficult...
if you are welding to colt it will be more wire shape..
regards,
Tks
p.s. the cracks are normal its because you take away the weld, the place where no crack is is penetrated i would buy a Tig 
[Edited on 25/5/06 by tks]
The above comments are always meant to be from the above persons perspective.
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t.j.
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| posted on 25/5/06 at 07:00 PM |
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quote:
Originally posted by NS Dev
more to the point why are you welding it??
Not something I would choose to weld
I build my frame out of 25x25x2
Ok it's heavier but who cares.
I understand that little cracks are caused by the high temp. I will use the grinder less Just wanted to know before i drive and my frame falls
apart.
Thanks, i will sleep better now.
Ps. how much weight will it be more because of my choice. Anyone?
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JoelP
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| posted on 25/5/06 at 07:11 PM |
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upping 1.6mm to 2mm would be about a 25% increase in weight. Maybe 25kgs? I dont know what an average chassis weighs.
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907
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| posted on 25/5/06 at 07:27 PM |
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14 kg's
Err, I think.
Paul G
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zetec7
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| posted on 26/5/06 at 04:52 AM |
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I found that turning down the wire speed and welding slower gave enough penetration to cure that problem - really work the puddle into the base
metal...
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kreb
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| posted on 26/5/06 at 02:04 PM |
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A couple notes: Only grind the weld flat if you really have to. Otherwise leave it a touch convex. In working with material this thin, it'd be
very easy to take off too much material and end up with a weak joint. Likewise with a TIG, it's rare that you're gap-free. In trying to
blend the material you're likely to end up with thin spots. For something structural I always add filler.
https://www.supercars.net/blog/wp-content/uploads/2016/04/1966_FiatAbarth_1000SP1.jpg
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