[vroemm]

Hi.

I found metal which might be useable for a frame for a CNC router.

It is blank silvery metal.
It is round.
It is magnetic.
It does not rust.
Any idea what metal this could be ?

The most important question:
It costs 1.10 euro per kilogram.
How cheap is this price ??

Thank you very much :-)

[posix]

It's probably stainless as the price is roughly right. But then the fact that it's round confuses me a little, since all metals are slightly tetrahedral in shape. Some are dodecahedral too. Maybe this is some alien metal? Maybe unobtanium? I'll have to look up it's specific mol values and mollecular structure and get back to you.













You didn't take all that seriously, did you?

[posix]

On a somewhat serious note working with unknown materials is a gamble at best.

why don't you just pop down into your local metal supply centre and get yourself some nice aluminium or steel extrusions and go from there rather than pay for something you don't know what is?

[vroemm]

On a somewhat serious note working with unknown materials is a gamble at best.
why don't you just pop down into your local metal supply centre and get yourself some nice aluminium or steel extrusions and go from there rather than pay for something you don't know what is?

Well, i did this a while ago, your question brought it back in my memory, thanks for that :-)
I payed 17.67 euro for 3 kilogram, 5.89 euro per kilogram.
Then 1.10 euro per kilogram is cheap.

What would suitable metal cost per kilogram to make a cnc router frame at a normal supplier ?

I found the round bars on a scrapyard.
+/- 50x700 mm, 9 kilogram a piece.
Thought is might make a nice frame part and slider bar at the same time.
A few ballbearing on it to slide.

[posix]

5.89 per kilogram of what? Aluminium-magnesium alloy?

Suitable cost per kilogram would be roughly 1 euro per kilogram of 4730 steel (which is basically your tool steel). A 16mm rod will be 3kg per meter, roughly. Aluminium is more in the 3-5 euro range. Your price of 5.89 euro per kilogram is silly, sorry. Or maybe that was something extremely hard (stainless steel is usually that expensive) that you don't really need.

For sliders you should look at pipes, not bars. Bars are heavy and pipes will offer you good stiffness and are much lighter. 20 or 25mm steel pipe with 2-3mm thick walls should be ok. Bigger diameter if you have more space of course. The bigger the better.

[jerber]

/quote
It is blank silvery metal.
It is round.
It is magnetic.
It does not rust.
Any idea what metal this could be ?
/quote

If it's magnetic it must be some sort of iron/steel.
Since it's magnetic it can't be stainless steel (RVS in dutch) but why doesn't it rust then ? Is it coated in any way maybe chromed ?
Can you post a picture ?
I'm curious.

btw €1,10/kilo sounds very cheap to me.

[posix]

Oh and I forgot, a 20mm with 2mm wall steel pipe with a seam is roughly 1 euro per kg, same dimension precision seam-less pipe is 2-3 euro per kg.

[posix]

If it is chromed steel it would be waaay more than 1.1euro per kg. Or you have found yourself a very cheap piece of steel there! But it, you will need it for something, not a machine though. Well, you could use it for rails but it's better to be used somewhere else.

[vroemm]

If it's magnetic it must be some sort of iron/steel.
Since it's magnetic it can't be stainless steel (RVS in dutch) but why doesn't it rust then ? Is it coated in any way maybe chromed ?
Can you post a picture ?

No, i do not have a picture.
But it looks much like a enormouse super big bar from a printer.

I'm curious.
btw €1,10/kilo sounds very cheap to me.

Me to :-)

[vroemm]

5.89 per kilogram of what? Aluminium-magnesium alloy?

Suitable cost per kilogram would be roughly 1 euro per kilogram of 4730 steel (which is basically your tool steel). A 16mm rod will be 3kg per meter, roughly. Aluminium is more in the 3-5 euro range. Your price of 5.89 euro per kilogram is silly, sorry. Or maybe that was something extremely hard (stainless steel is usually that expensive) that you don't really need.

It was C35 steel (What ever that means.)

Possibly it was the price of the steel + extra cost to cut it to one meter.
Then the price of the steel becomes unknown.

For sliders you should look at pipes, not bars. Bars are heavy and pipes will offer you good stiffness and are much lighter. 20 or 25mm steel pipe with 2-3mm thick walls should be ok. Bigger diameter if you have more space of course. The bigger the better.

Have you ever measured how much one meter 25x3 mm pipe bents when you put 10 kilo on it ?
I expect it bents to much.
A while back i did some measuring on metal to see how much it bents.
It bents a whole lot more then i expected.

My goal is to make a cnc router which makes things with 0.05 mm accuracy.
Well, one can dream, can't one :-)

.

[jerber]

No, i do not have a picture.
But it looks much like a enormouse super big bar from a printer.

Maybe they were part of a hydraulic cilinder ?

If so they are very suitable as rails.

[Mcgyver]

/quote
Since it's magnetic it can't be stainless steel .

usually, sometimes true. 400 series (martensitic) IS magnetic and even 300 series can be workhardened into having local magnetic spots. interestly (well to me anyway) magnetic spots in austenitic (300) can be removed by normalizing. granted 300's are more common, but its not a definitive test.

[Geof]

From vroemm:

It is blank silvery metal.
It is round.
It is magnetic.
It does not rust.

It was C35 steel (What ever that means.)

C35 is carbon steel, complete name is C1035. This steel does rust so your bars must have a coating. I think Jerber is close; in Canada it is possible to get steel bar hard chrome plated and ground to a very accurate size and it is used for hydraulic cylinder rods.

And two comments for jerber:
Some nickel alloys are magnetic so being magnetic does not always mean a metal is iron or steel.
Some stainless steels are magnetic.

[vroemm]

C35 is carbon steel, complete name is C1035. This steel does rust so your bars must have a coating.

There is a break down in communications :-)
The C35 i bought a year ago and was mentioned here to compare the price.
The 50x700 mm bars i found on a scrapyard are not C35.

The 50x700 does not have a coating, i can see it on the cut side.

[Geof]

My mistake. Reading too fast. I would say most likely stainless steel then.

[jerber]

And two comments for jerber:
Some nickel alloys are magnetic so being magnetic does not always mean a metal is iron or steel.
Some stainless steels are magnetic.

Thanks I didn't knew that.

[vroemm]

Hi..

I just bought the 45x718 mm round metal bars that started this subject at the scrapyard.
For 0.50 euro per kilogram, instead of 1.10 euro/kg. Price seems to have changed :-)

Turns out there are a numbers on the side.
1.4057
528001

1.4057 means its a hardenable stainless steel.
http://www.valbrunanordic.se/dokumen...0402%20ENG.pdf

What does the 528001 mean ?

It will be very strong slider bars for my cnc router.
Until then it can be used for weight lifting, good for my muscles :-)

Thanks folks for your help :-)

[DUCK]

There are non-ferous materials that are magnetic; take nickel and cobalt for example. (It could be nickel or a nickel alloy, but I seriously doubt it; last I checked that stuff was considerably pricery than steel)