Hi, I am needing some help ?

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Wendy
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Joined: Mon Nov 17, 2003 4:27 pm

Hi, I am needing some help ?

Post by Wendy » Mon Nov 17, 2003 4:35 pm

I am just about to start learning some basic welding.


I asked a friend to pick up some offcut Mild steels bits from a local enginnering firm, I was looking at them earlier on and it looks like Stainless Steel to me rather then Mild Steel.


Is there any easy way of telling what type of steel plate I have ?

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gglines
Posts: 113
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Re: Hi, I am needing some help ?

Post by gglines » Mon Nov 17, 2003 4:50 pm

Many stainless steels are not magnetic, so that is one easy test. You can also spark the metal on a grinder and compare with known samples of stainless and mild steels.

George

Wendy
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Joined: Mon Nov 17, 2003 4:27 pm

Re: Hi, I am needing some help ?

Post by Wendy » Mon Nov 17, 2003 5:07 pm

Many stainless steels are not magnetic, so that is one easy test. You can also spark the metal on a grinder and compare with known samples of stainless and mild steels.

George

Could you explain that a little bit more for me ?


Many thanks

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Jacin
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Location: Near Cleveland, Ohio

Re: Hi, I am needing some help ?

Post by Jacin » Mon Nov 17, 2003 5:30 pm

Often times stainless is NON MAGNETIC so a test with a magnet can often confirm the notion of stainless.

Steel in general has varying degrees of carbon in it - the three general types high, medium, low carbon - which are easily (somewhat) distinguishable by performing a spark test- grind the material and note the spark pattern it gives off - it is adviseable to compare this to a known standard as SOMETIMES the grinding wheel can impart impurities that can fool you. Mild steel (low carbon) steel produces a spark that has little to nothing happening at the tip, Medium carbon steel produces a spark that has a small secondary spark trail off the tip of the major spark stream, and lastly HIGH carbon steel has s sort of starburt at the tip of each spark stream tip. Tough to describe in words - recently I saw a chart going into far more detail than just High, Medium, Low carbon spark streams - maybe it was that Government Link posted a few days ago - can't remember! (shoulda printed it)

ANyways for practice welding I'd stick with any old junk but try to keep it in the low, medium or stainless range - with low carbon being FIRST choice! And even though medium carbon and High carbon even stainless "seem" easy to weld - they are infact quite difficult to get a "sound" weld as the carbon becomes your enemy. Stainless is another animal all together.

Spark tests are a welders friend as it gives him/her an idea of what they are fighting.

I hope this helps

Wendy
Posts: 3
Joined: Mon Nov 17, 2003 4:27 pm

Re: Hi, I am needing some help ?

Post by Wendy » Mon Nov 17, 2003 5:50 pm

Often times stainless is NON MAGNETIC so a test with a magnet can often confirm the notion of stainless.

Steel in general has varying degrees of carbon in it - the three general types high, medium, low carbon - which are easily (somewhat) distinguishable by performing a spark test- grind the material and note the spark pattern it gives off - it is adviseable to compare this to a known standard as SOMETIMES the grinding wheel can impart impurities that can fool you. Mild steel (low carbon) steel produces a spark that has little to nothing happening at the tip, Medium carbon steel produces a spark that has a small secondary spark trail off the tip of the major spark stream, and lastly HIGH carbon steel has s sort of starburt at the tip of each spark stream tip. Tough to describe in words - recently I saw a chart going into far more detail than just High, Medium, Low carbon spark streams - maybe it was that Government Link posted a few days ago - can't remember! (shoulda printed it)



I hope this helps

Many thanks, I will have a go at that tomorrow.

That throws out my theory that I could leave it out in the rain overnight and see if surface rust formed [img]/ubb/images/graemlins/crazy.gif"%20alt="[/img]


Cheers

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