grinding metals

[james123]

hi i am realy puzzled recently i have been grinding one of my bmx bike frames up and i cant work out what metals it is made out of i think it is aluminium but i was told that aluminium dosnt spark, but my bike frame is. could someone help please and tell me how to identify my metals sorry newby

 

[SwissTony]

Don't think its a good idea to grind Aluminium, as it can clog the disk up and damage the disk.

Not sure if Ali sparks while grinding.
I know it can be a fire hazard, as they use it in the construction of fireworks to make nice bangs.

 

[the snooper]

ally doesnt spark steel does test with a magnet

 

[weldequip]

More likely to be 4130 Chro-Moly; what's the frame?

 

[james123]

thanks every1 for the replys, hi weldequip its a we the people trust frame 2008 model iv had a look and i think its what you said i just have a massive crack under the top and bottom tube that will need welded hopfully

 

[weldequip]

Expensive then eh. Don't bother trying to do it yourself, take it back to the shop & get a Pro to do it - you'll only balls it up. What's an original 1980's Patterson Racing frame worth incidently, any idea

 

[chunkolini]

Sounds dodgy to me.
BMX bikes have a violent life, I would figure 'it's cracked it's fecked' and cry into my cider.

Chunko.

 

[james123]

hi weldequip im not quite sure becuase im into bmxing but if it an original frame it will probly be worth quite a bit if its in good condition try having a scan through ebay that normal does me quite well when i need price ranges.

 

[outofthefire]

Don't think its a good idea to grind Aluminium, as it can clog the disk up and damage the disk.

Not sure if Ali sparks while grinding.

Why did you reply if you dont even know if alli sparks or not. There is nothing wrong with cutting aluminium with a grinder, there are better methods but if a grinders all you've got then thats all you can use, soft pads are better than grinding disks though you got that bit right they do clog up, but ally also clogs files up.

I know it can be a fire hazard, as they use it in the construction of fireworks to make nice bangs.

On its own its not a fire hazard in the slightest, however aluminium mixed in the right proportions with iron oxide becomes thermite an extremely hot burning substance used to weld have a look here for more info http://www.mig-welding.co.uk/forum/showthread.php?t=8609&highlight=thermite&page=2

 

[Pete.]

Ally cuts quite well with the very thin cutting discs.