What's new
What's new

HSCO vs Carbide End Mills for General Shop Use

NLan07

Plastic
Joined
Dec 27, 2021
Here comes a journey of a thousand miles
Don

Sooo true! As an engineer I love maximizing things and getting every bit of performance and efficiency out of whatever I'm working on, and my journey so far into getting the best recipes for machining as fast, reliably, and as efficiently as possible definitely feels like it's going to be a long journey.
 

BT Fabrication

Stainless
Joined
Nov 3, 2019
as a job shop, the initial investment in a $150+ endmill for one job doesn't pay off if its a $50 part. thats where a $8 HSS endmill come into play, i prefer HSS as it is more forgiving in certain applications.
 

mhajicek

Titanium
Joined
May 11, 2017
Location
Minneapolis, MN, USA
If you're going to use it once, and the HSS will do, you can get away with it. If you're going to keep using it, get the carbide. It may cost two or three times as much, but will last ten times as long, and perform far better while it does so.
 

CarbideBob

Diamond
Joined
Jan 14, 2007
Location
Flushing/Flint, Michigan
Not sure where the line is drawn between high speed steel and high speed steel cobalt.
Perhaps someone could explain the crossover or in between on the callouts and numbering.
There is M2 and M42..:willy_nilly:
Can high cobalt types tend to become to be more brittle like carbide is and no so liking abuse and a beating?
Bob
 

DMF_TomB

Diamond
Joined
Dec 13, 2008
Location
Rochester, NY, USA
over 1" dia many will rough with carbide inserts mills especially 1.5 to 3" dia
you can get multiple row insert mills
.
they might finish (side mill) using a long hss or cobalt end mill. cobalt usually
much better for alloy steels that dull quickly with hss.
.
crestcut mills with wavy flutes many use where better finish and less vibration
is needed especially over 3" depth
 

CITIZEN F16

Titanium
Joined
May 2, 2021
i wouldnt be surprized if there were more than 100 different hss alloys on the market today.

I definitely agree, with varying degrees of hardness. I used to turn down shanks of HSS drills ages ago to use them in machines with drill collet holders that had a 3/8" max on machines that would accept up to 13/16 (.8125) stock.
They all just said HSS, some of them you could turn down 5 dozen with just a standard C2 grade brazed carbide turning tool on a single sharpening, with others doing 3 of them would eat a high grade coated carbide insert.
 

dian

Titanium
Joined
Feb 22, 2010
Location
ch
Not sure where the line is drawn between high speed steel and high speed steel cobalt.
Perhaps someone could explain the crossover or in between on the callouts and numbering.
There is M2 and M42..:willy_nilly:
Can high cobalt types tend to become to be more brittle like carbide is and no so liking abuse and a beating?
Bob

the question is brittle at what temperature? usually data is at room temp, which really doesnt mean much (unless you crash into the vice). this is an interessting graph of something like o2, d3/4, m1, m2 and t15. at 500°c they are similar, at 600°c they differ. i whish the cobalt variaties were on there too. (its bending fracture toughness against tempering temp.)

no idea how to make it larger.
 

Attachments

  • hss bruchbiegearbeit.jpg
    hss bruchbiegearbeit.jpg
    14 KB · Views: 17

steve-l

Titanium
Joined
Mar 2, 2012
Location
Geilenkirchen, Germany
There is one other argument not mentioned here. I have no argument with you CNC guys on the value of insert tooling in your production environment with 20 to 30 horsepower spindles. I'm certain your preferences are correct. I run a job shop and my preference is 99% HSS with cobalt for both my mills and lathes. HSS tools are sharper and can use more relief than insert tooling. Consequently, they create significantly less tool loading and heat, which benefits lighter manual machines. As others have also mentioned, they are also infinitely cheaper. In a job shop environment, 90% of job time is machine setup not machining.
 

plastikdreams

Diamond
Joined
May 31, 2011
Location
upstate nj
Just to prove the cost difference is irrelevant I went to msc and looked...

.500 4 flute 1.000 loc AlTiN square center cutting

Cobalt $36.27
Carbide $41.80

I'm sorry, carbide wins hands down. It can cut more things faster, longer, and harder. I use them on a Bridgeport daily , as long as you don't drop or crash them they will go for a while. I have some that are over a year old and see materials from delrin to 17-4.
 

Milland

Diamond
Joined
Jul 6, 2006
Location
Hillsboro, New Hampshire
I definitely agree, with varying degrees of hardness. I used to turn down shanks of HSS drills ages ago to use them in machines with drill collet holders that had a 3/8" max on machines that would accept up to 13/16 (.8125) stock.
They all just said HSS, some of them you could turn down 5 dozen with just a standard C2 grade brazed carbide turning tool on a single sharpening, with others doing 3 of them would eat a high grade coated carbide insert.

There's the aspect of how the shanks were tempered (drawn down) that would affect tool life too. Drill shanks are purposely softer than the flutes to allow chucks to grip them, but some vendors might leave them harder than others. The length of the drawn area might vary too, leading to some cuts being in flute-hard material.

Aside from that, or major material changes (cobalt, fancy PM steels), I suspect that most shanks would cut about the same at identical hardnesses.
 

DMF_TomB

Diamond
Joined
Dec 13, 2008
Location
Rochester, NY, USA
Cobalt can take vibration much better than carbide, Cobalt is much cheaper
when 1" dia or bigger and 4" or longer flutes, I have broke many 1" to 2" dia
end mill usually when part of a complex part is sticking out more than tolerance.
hard to describe.
.
Tungsten Carbide inserts made for finishing can make shiny mirror finish
BUT it requires high sfpm or rpm literally
.
2.5" dia might work best at 1800 rpm
1.5" dia like 2700 rpm
2" dia about 2000 rpm
.
and a lot of testing at different feeds and speeds even if mill runs
at 1300 sfpm rather than 900 sfpm vibration chatter in mill, tool holder,
part and fixture / vise can give a bad finish and short tool life
.
many many many times I have had to adjust feeds and speed for the part and
tool holder and fixture. horizontal mills often the tooling is relatively
long to reach part in center of pallet. Big difference end milling with
a short tool holder and same mill in a long tool holder.
literally feed can go from 80.ipm down to 1.ipm if you running slow rpm to
lower vibration than often cobalt works better or cheaper
.
even with vertical mill often got to circular mill bore 12" or more
deep into part, not possible obviously with short tooling
 

Attachments

  • ShinyTunalloyFinish.jpg
    ShinyTunalloyFinish.jpg
    43.4 KB · Views: 16
  • ToolingRack.jpg
    ToolingRack.jpg
    84.4 KB · Views: 19
  • ToolingLonger.jpg
    ToolingLonger.jpg
    88.1 KB · Views: 17

plastikdreams

Diamond
Joined
May 31, 2011
Location
upstate nj
Cobalt can take vibration much better than carbide, Cobalt is much cheaper
when 1" dia or bigger and 4" or longer flutes, I have broke many 1" to 2" dia
end mill usually when part of a complex part is sticking out more than tolerance.
hard to describe.
.
Tungsten Carbide inserts made for finishing can make shiny mirror finish
BUT it requires high sfpm or rpm literally
.
2.5" dia might work best at 1800 rpm
1.5" dia like 2700 rpm
2" dia about 2000 rpm
.
and a lot of testing at different feeds and speeds even if mill runs
at 1300 sfpm rather than 900 sfpm vibration chatter in mill, tool holder,
part and fixture / vise can give a bad finish and short tool life
.
many many many times I have had to adjust feeds and speed for the part and
tool holder and fixture. horizontal mills often the tooling is relatively
long to reach part in center of pallet. Big difference end milling with
a short tool holder and same mill in a long tool holder.
literally feed can go from 80.ipm down to 1.ipm if you running slow rpm to
lower vibration than often cobalt works better or cheaper
.
even with vertical mill often got to circular mill bore 12" or more
deep into part, not possible obviously with short tooling

If you read my last post you will see it's not much less expensive. And really, who is talking about massive tools here, no one.
 

DMF_TomB

Diamond
Joined
Dec 13, 2008
Location
Rochester, NY, USA
If you read my last post you will see it's not much less expensive. And really, who is talking about massive tools here, no one.

you talking a 1/2" dia short flute length end mill, I dont know anybody finish milling
a 3" deep side of a part with a short 1/2" dia end mill. even make small parts I often
mill 4" to 6" deep into a part usually that requires 1"dia or more
 

CITIZEN F16

Titanium
Joined
May 2, 2021
There is one other argument not mentioned here. I have no argument with you CNC guys on the value of insert tooling in your production environment with 20 to 30 horsepower spindles. I'm certain your preferences are correct. I run a job shop and my preference is 99% HSS with cobalt for both my mills and lathes. HSS tools are sharper and can use more relief than insert tooling. Consequently, they create significantly less tool loading and heat, which benefits lighter manual machines. As others have also mentioned, they are also infinitely cheaper. In a job shop environment, 90% of job time is machine setup not machining.

It depends on what you are machining and the quantity. There are a lot of materials that will eat uncoated HSS tooling like a kid eats candy.
 

CITIZEN F16

Titanium
Joined
May 2, 2021
Cobalt can take vibration much better than carbide, Cobalt is much cheaper
when 1" dia or bigger and 4" or longer flutes, I have broke many 1" to 2" dia
end mill usually when part of a complex part is sticking out more than tolerance.
hard to describe.
.
Tungsten Carbide inserts made for finishing can make shiny mirror finish
BUT it requires high sfpm or rpm literally
.
2.5" dia might work best at 1800 rpm
1.5" dia like 2700 rpm
2" dia about 2000 rpm
.
and a lot of testing at different feeds and speeds even if mill runs
at 1300 sfpm rather than 900 sfpm vibration chatter in mill, tool holder,
part and fixture / vise can give a bad finish and short tool life
.
many many many times I have had to adjust feeds and speed for the part and
tool holder and fixture. horizontal mills often the tooling is relatively
long to reach part in center of pallet. Big difference end milling with
a short tool holder and same mill in a long tool holder.
literally feed can go from 80.ipm down to 1.ipm if you running slow rpm to
lower vibration than often cobalt works better or cheaper
.
even with vertical mill often got to circular mill bore 12" or more
deep into part, not possible obviously with short tooling

No need for your tool collection in my shop, most everything I make will fit in a shirt pocket.
 

bosmos_j

Hot Rolled
Joined
Jun 9, 2015
To get us started we purchased carbide end mills in 1/8", 1/4", 3/8", 1/2", and 3/4" sizes specific for both steels (5 flute, AlTiN coated) and aluminum/non-ferrous alloys (3 flute, ZrN coated), but currently that's as big we have.

In contrast, and as a specific example, our local vendor is selling these 1" dia, 3" LOC, 5 flute TiAlN coated roughers https://www.niagaracutter.com/search?expand=N53924for $165 EA which is roughly 50% off what I've been able to find it for online.

I don't work in anything that big. 1/2" end mill is "big" in my shop. On your example, I'm not seeing the screaming good deal.

Maritool has 1" dia, 3" LOC carbide from $260-320, so "list" price you see online for HSSCO is about that? Something not right.

Tool Holders, Collets and Machine Accessories 4 fl. sqr Single End - MariTool

Tool Holders, Collets and Machine Accessories 5 Flute and Higher - MariTool

How many of these thing do you need? Don't buy it until you need it. Common mistake starting out is to buy a bunch of stuff you think you'll need. You'll be wrong once you figure out what you're doing. Giant HSSCO EMs seem like dinosaurs sitting around in the warehouse nobody's buying. I'm sure there's a specific application they're better for, but until you know that's yours, I'd steer clear.
 








 
Top