johnq
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posted on 25/1/11 at 06:47 PM |
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HOW
hi can someone tell me how to repair a broken (iron) casting, there is no stress on this item,purely cosmetic, weld .braze etc, thanks in advance,
john,
looks like rain again
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prawnabie
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posted on 25/1/11 at 06:49 PM |
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superglue, araldite?
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designer
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posted on 25/1/11 at 07:01 PM |
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Cast iron can be welded.
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AndyW
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posted on 25/1/11 at 07:03 PM |
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JB weld.......
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mangogrooveworkshop
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posted on 25/1/11 at 07:04 PM |
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Is it the rhones or cast guttering your on about?
A very good clean with the wire brush and tack weld it together .
Then mig it a short section at a time making sure its hot all over the piece.
If you go too fast it cracks ......
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johnq
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posted on 25/1/11 at 07:07 PM |
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its actualy a garden trough similar cast to guttering. ile give mig a try,thanks all.
looks like rain again
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snapper
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posted on 25/1/11 at 07:10 PM |
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You should really heat the piece up very hot, weld it then pack it in (fireproof) insulation and leave to cool for days.
Brazing is much more kind and safer.
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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MikeR
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posted on 25/1/11 at 07:37 PM |
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For cast i thought Mig wasn't good - heat too concentrated so that area expands and contracts too much. Thought Arc was much better, esp as they
do rods for cast (but this may also need pre-heat, no idea as i've never done it).
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austin man
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posted on 25/1/11 at 07:43 PM |
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get the good old sticck welder out make sure you heat the item prir to welding or the cooling process can stress the repair
Life is like a bowl of fruit, funny how all the weird looking ones are left alone
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PSpirine
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posted on 25/1/11 at 07:54 PM |
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I welded some pig iron with some "cast" welding rods in a bog standard stick welder. First blast it with a gas blow-torch so you get it
nice and red around the crack (in my case). As said, let it cool REALLY slowly - stick in an oven if at all possible.
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hillbillyracer
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posted on 25/1/11 at 08:10 PM |
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As said use proper cast rods (not cheap!) & if you can warm the whole area up a bit then it does help with the thermal shock. Another thing to do
is weld it in short sections, about an inch at a time & tap the weld as it cools for a few seconds with a blunt chisel then weld another inch or
so. Welding in short bursts then waiting 15-20 seconds stops too much heat build up & the tappin relieves the stresses apparently.
If it's got a side that is'nt seen & so does'nt matter cosmeticly then you can weld some strips of mild steel across the join if
you want to help tie it together, the cast rods will weld the two together.
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Minicooper
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posted on 25/1/11 at 08:28 PM |
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I welded a cast iron fire place back together when it split in two while removing it. I arc welded it using cast rods, welded up a treat even though
it was a five foot weld, I welded it on the back side and as it welded it pulled the join tighter and tighter until it was invisible on the front
I welded cast steel with a mig no problem but when I tried to weld cast iron it made a real mess
Cheers
David
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escary
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posted on 25/1/11 at 08:38 PM |
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electric arc
cast rods or dis-similar, heat prior to welding and it'll be less likely to crack
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madteg
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posted on 25/1/11 at 09:04 PM |
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Pre heat till red use cast rods 90% nickle if you can afford them and let cool slowly also dont forget to gring a good prep on it (v groove)
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johnq
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posted on 27/1/11 at 10:42 AM |
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thanks all. stick it is,,
looks like rain again
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baz-R
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posted on 29/1/11 at 07:53 PM |
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pre heat and weld with stainless (non mag type) or braze with mig or gas
your weld will just crack off if you just weld it normal
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