I have a Glanze 16mm SCLCR boring bar that I need to shorten and slightly 
reduce the diameter at the non-business end so that I can fit it into my 
boring head (I couldn't find 5/8" bars anywhere). Before I destroy any 
tooling, anyone know if these are hardened? OK, I could try the file test 
but I thought I would ask first in case anyone's tried cutting one.
TIA, Martin.
-- 
martin<dot here>whybrow<at here>ntlworld<dot here>com

On Thu, 4 Sep 2008 14:19:33 +0100, "Martin Whybrow"
 wrote:

>I have a Glanze 16mm SCLCR boring bar that I need to shorten and slightly 
>reduce the diameter at the non-business end so that I can fit it into my 
>boring head (I couldn't find 5/8" bars anywhere). Before I destroy any 
>tooling, anyone know if these are hardened? OK, I could try the file test 
>but I thought I would ask first in case anyone's tried cutting one.
>TIA, Martin.


They are certainly hardened, but I haven't measured how hard.

I would expect to be able to take a 2.5 thou cut to get to 5/8" with a carbide
insert and get a nicer finish than if the steel were annealed.

Shortening it might be more trouble. If it ruined a carbon steel hacksaw
blade, I'd use a cutting disk on the surface grinder.


Mark Rand
RTFM

"Mark Rand"  wrote in message 
news:qi40c41jasv545ago4m32fk41vth56rhj5@4ax.com...
> On Thu, 4 Sep 2008 14:19:33 +0100, "Martin Whybrow"
>  wrote:
>
>>I have a Glanze 16mm SCLCR boring bar that I need to shorten and slightly
>>reduce the diameter at the non-business end so that I can fit it into my
>>boring head (I couldn't find 5/8" bars anywhere). Before I destroy any
>>tooling, anyone know if these are hardened? OK, I could try the file test
>>but I thought I would ask first in case anyone's tried cutting one.
>>TIA, Martin.
>
>
> They are certainly hardened, but I haven't measured how hard.
>
> I would expect to be able to take a 2.5 thou cut to get to 5/8" with a 
> carbide
> insert and get a nicer finish than if the steel were annealed.
>
> Shortening it might be more trouble. If it ruined a carbon steel hacksaw
> blade, I'd use a cutting disk on the surface grinder.
>
>
> Mark Rand
> RTFM
Thanks Mark. I haven't got any other indexable turning tools but I do have 
some brazed carbide tools, not sure if they've got enough of an edge to take 
a fine cut though. I've had good luck cutting case hardened steel of around 
60 -65 HRc with carbide tile hacksaw blades so I may try that to shorten it, 
otherwise it will have to be an angle grinder as I'm lacking a surface 
grinder (and the space for one at the moment).
Martin
-- 
martin<dot here>whybrow<at here>ntlworld<dot here>com

"Martin Whybrow"  wrote in message 
news:c9Vvk.80722$Ff2.39767@newsfe13.ams2...
>
>
> "Mark Rand"  wrote in message 
> news:qi40c41jasv545ago4m32fk41vth56rhj5@4ax.com...
>> On Thu, 4 Sep 2008 14:19:33 +0100, "Martin Whybrow"
>>  wrote:
>>
>>>I have a Glanze 16mm SCLCR boring bar that I need to shorten and slightly
>>>reduce the diameter at the non-business end so that I can fit it into my
>>>boring head (I couldn't find 5/8" bars anywhere). Before I destroy any
>>>tooling, anyone know if these are hardened? OK, I could try the file test
>>>but I thought I would ask first in case anyone's tried cutting one.
>>>TIA, Martin.
>>
>>
>> They are certainly hardened, but I haven't measured how hard.
>>
>> I would expect to be able to take a 2.5 thou cut to get to 5/8" with a 
>> carbide
>> insert and get a nicer finish than if the steel were annealed.
>>
>> Shortening it might be more trouble. If it ruined a carbon steel hacksaw
>> blade, I'd use a cutting disk on the surface grinder.
>>
>>
>> Mark Rand
>> RTFM
> Thanks Mark. I haven't got any other indexable turning tools but I do have 
> some brazed carbide tools, not sure if they've got enough of an edge to 
> take a fine cut though. I've had good luck cutting case hardened steel of 
> around 60 -65 HRc with carbide tile hacksaw blades so I may try that to 
> shorten it, otherwise it will have to be an angle grinder as I'm lacking a 
> surface grinder (and the space for one at the moment).
> Martin

I shortened the bar this afternoon; I tried a normal hacksaw and was 
surprised to find that it cut fairly easily, I was expecting the blade to 
glance off. Faced off then turned the shank to the required OD with  HSS 
tools.
Clearly the Glanze bars are not hardened!
Martin
-- 
martin<dot here>whybrow<at here>ntlworld<dot here>com

On Fri, 5 Sep 2008 19:50:03 +0100, "Martin Whybrow"
 wrote:


>
>I shortened the bar this afternoon; I tried a normal hacksaw and was 
>surprised to find that it cut fairly easily, I was expecting the blade to 
>glance off. Faced off then turned the shank to the required OD with  HSS 
>tools.
>Clearly the Glanze bars are not hardened!
>Martin


There's quite a difference between hardened and "too hard to cut" :-)

I've been doing a fair amount of playing with EN24 recently. Annealed, it's
gummy and horrible to cut. Hardened and tempered to 100C You can barely touch
it with HSS, the tool bounces off. Tempered to 250C it's hard to cut, but you
get a beautiful finish...


Tool holders should be hardened to maximum toughness rather than maximum
hardness. This will reduce scarring from clamping screws etc, stop the insert
screws from stripping the threads out and increase the ultimate tensile
strength of the tool.

A good way to tell if a piece of steel is hardened is to accidentally drop it
on the concrete floor. Annealed steel ends up with the corners dented and
burred. Hardened and not tempered, you might get two lumps of steel back from
the one that you dropped. Hardened and tempered right, you pick it up and dist
the concrete dust off it. On second thoughts, that's not a very good method
:-(

At lease, that's the way I see it.


Mark Rand
RTFM