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Tenson
25-10-2015, 06:26 PM
Is there an easy way to tell if a cutter is tungsten steel or tungsten carbide?

For example here the listing title says 'Carbide' but in the description it says 'Material: Imported Tungston Steel'

http://www.aliexpress.com/item/5pcs-3-175x8MM-Down-cutter-left-helical-one-flute-left-spiral-carbide-cnc-router-bits-end/32324275138.html?spm=2114.01020208.3.10.Lha9lU&ws_ab_test=searchweb201556_7_71_72_73_74_75,search web201527_3,searchweb201560_9

magicniner
25-10-2015, 08:13 PM
For cheap stuff just buy one and see what turns up, you can tell tungsten carbide by it's attraction to a magnet, it's quite magnetic but considerably less so than steel.
I buy small endmills locally as they're not much cheaper on internet sites for quality branded items,

- Nick

johnsattuk
25-10-2015, 08:35 PM
Is there an easy way to tell if a cutter is tungsten steel or tungsten carbide?

Weight is a good indicator TC ~ 15 gm/cc - HSS ~8gm/cc, quite noticeable when you pick one up.

Christian Knuell
25-10-2015, 10:40 PM
Hi,

the description mentions the tools to be designed for Acrylic and PVC - so high chance for HSS which wouldn't even be a bad choice for this kind of application.
HSS can be ground significantly sharper and is much more ductile than carbide - the first being interesting for acrylic and the latter in case your tools tend to break before getting dull.

But if you really want to know you need to ask the seller for clarification or just buy and see what you get.

Christian

Tenson
26-10-2015, 02:06 PM
I have some cutters I bought from another seller that simply stated 'Carbide'. However I still wonder. It's certinaly less magnetic than a known 'HSS' cutter I have. Wouldn't tungsten steel also be less magnetic though, due to the percentage of added tungsten?

Is high speed steel and tungsten steel the same thing?

johnsattuk
26-10-2015, 02:21 PM
Discription: It is a high performance steel with high hardness and good wear resistance properties.It is often used as a cutting tool as it can cut metal at very high rate than any other carbon tool steel due to presence of tungsten and cobalt that gives it much higher strength.
Application: It is mainly used in manufacturing of cutting tools such as twist drills, reamers, machine bits, taps. dies, saw blades and other cutting tools etc.

Tenson
26-10-2015, 02:43 PM
Your description is of HSS I assume? So high speed steel is steel with the presence of tungsten, meaning it's the same thing as 'tungsten steel'?

In which case my 'solid carbide' cutters that are noticeably less magnetic than my HSS cutter must have a much higher tungsten content?

komatias
26-10-2015, 04:17 PM
Solid carbide is not steel. It is a tungsten carbide grit material that is held together with 6-9% Cobalt. Some alloying agents may be used too. The only reason it is slightly magnetic is because of the cobalt.

Tungsten steel has some 0.5% to around 5% tungsten as an alloying agent. It does not significantly alter the magnetic properties.

A sure fire way to tell if you have a steel or a tungsten carbide is, as already mentioned, the weight.

A 6mm endmill that is 40mm long should weigh around 9grams. A solid carbide will weigh around 17 grams. If you do not have scales to hand but you have time, dip the blunt end in vinegar and see which one rusts.

Tenson
26-10-2015, 04:22 PM
Given the amount of material removed from the cutter to form the flutes it is a little tricky to tell the weight it would be in each material, unless you have an identical HSS to compare with. That said, the ones I've got seem bloody heavy for the size.

Actaully it is easy to tell as I have a larger 'HDS' cutter and it is less heavy than the smaller carbide one. So I guess I can trust it is solid.