Why to an would a m...
 

[Closed] Why to an would a magnet stick to a Specialized Aluminium frame?

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http://www.specialized.co.uk/us/en/bikes/archive/2005/hotrockgirlsbikes/05hotrock206-speedgirls

Why would a magnet stick to a 2005 Hotrock frame? The specs say it is Aluminium???


 
Posted : 02/08/2013 8:59 pm
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Some sort of metallic paint? To be honest, given the weight of those things, it's probably aluminium tubing filled with hi-ten steel.


 
Posted : 02/08/2013 9:05 pm
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The paint is metallic so possibly...any one able to confirm??


 
Posted : 02/08/2013 9:08 pm
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Where are you putting the magnet?
Welds, gussets, bottle cage bolts, headset races, probably the BB threads will all be steel. May have a steel seatpost too so it's sticking to that rather than the alu frame.


 
Posted : 02/08/2013 9:09 pm
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it won't be the paint.

It is more likely something like a steel seat post etc.


 
Posted : 02/08/2013 9:18 pm
 gee
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Welds and gussets will be steel? Eh?


 
Posted : 02/08/2013 9:45 pm
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How do you weld aluminium with steel?


 
Posted : 02/08/2013 9:56 pm
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remind me not to buy a frame that Crazy Legs has made ๐Ÿ™‚


 
Posted : 02/08/2013 10:22 pm
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Did you 'steel' it?!? Haw haw!!!! ๐Ÿ˜‰


 
Posted : 02/08/2013 10:34 pm
 JoeG
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You obviously have an Aluminum magnet instead of a steel one! ๐Ÿ˜‰


 
Posted : 02/08/2013 10:38 pm
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Is it aluminium or aluminium alloy? Some alloys are magnetic.


 
Posted : 02/08/2013 10:38 pm
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Does it stick every where with a good solid thunk? Or just a few special places


 
Posted : 02/08/2013 10:39 pm
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It won't, It's sticking to some iron/steel nearby. Or the bike is just sticky - sap etc?


 
Posted : 02/08/2013 10:41 pm
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Pfffft! ampthill said "special place", chortle!


 
Posted : 02/08/2013 10:42 pm
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too late for an edit

๐Ÿ™„


 
Posted : 02/08/2013 11:00 pm
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Do you check all your frames for magnetism?


 
Posted : 02/08/2013 11:02 pm
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Posted : 02/08/2013 11:07 pm
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We have one. I think the seat post is steel and goes through most of the seat tube. (It's in the car or I'd check.)


 
Posted : 02/08/2013 11:31 pm
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Maybe she's oiled it with ferrofluid?


 
Posted : 02/08/2013 11:35 pm
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nick1962 - Member
Do you check all your frames for magnetism?

I guess I might if I was going to buy a 2nd hand bike and suspected it wasn't what the stickers said

though more likely the seat post is the answer


 
Posted : 03/08/2013 6:30 am
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You can see if it's Ally by looking at the welds anyway.


 
Posted : 03/08/2013 8:46 am
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Can you? What's the difference?


 
Posted : 03/08/2013 8:50 am
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I just had a look at mine and the welds on the steel bikes look smaller. Is that what you mean?


 
Posted : 03/08/2013 8:51 am
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Sit down and watch it for a couple of decades or so. If it's steel you might notice some rust appear.


 
Posted : 03/08/2013 8:58 am
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Haha!


 
Posted : 03/08/2013 8:59 am
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Yep, that's what I mean.

IDK if it's to do with the wall thickness or what but usually Aluminium Alloy frames have welds something like 5-8mm wide, and Steel ones 3 or 4 wide.


 
Posted : 03/08/2013 9:15 am
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Nope sold it and buyer is complaining. I have an identical one and a magnet does stick, I have a couple of other hotrocks and it doesn't stick at all to them. Very odd...


 
Posted : 03/08/2013 10:22 am
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well a quick google says 2003 models were steel - pic shows a straight top tube - think the ali models had a formed top tube to give stand over though they recently switched back to straight


 
Posted : 03/08/2013 1:55 pm
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Is it aluminium or aluminium alloy? Some alloys are magnetic.

I don't think very much is made from pure aluminium, all bikes frames will be an aluminium alloy.


 
Posted : 03/08/2013 4:06 pm
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No aluminium alloys I know of are magnetic - they'd have to have a lot of iron in them. Even stainless steel isn't very magnetic.

I'd guess either it's not the frame you thought it was, or it's steel rivnuts. Get her to send you a picture of the magnet sticking.


 
Posted : 03/08/2013 5:54 pm