Router Bits/True or False - Router Forums
 
LinkBack Thread Tools Display Modes
post #1 of 8 (permalink) Old 10-13-2004, 12:54 PM Thread Starter
Retired Moderator

 
-Sam-'s Avatar
 
Join Date: Sep 2004
Country: United States
First Name: Sam
Posts: 639
 
Question Router Bits/True or False

Is it true that half inch shank router bits stay sharp longer than quarter inch shank router bits? I never heard of that. It sounds like it would make sense though. Bigger bit, more carbide, etc. Thanks!

Last edited by -Sam-; 10-13-2004 at 12:59 PM.
-Sam- is offline  
Sponsored Links
Advertisement
 
post #2 of 8 (permalink) Old 10-13-2004, 01:16 PM
The Router Guys

 
BobandRick's Avatar
 
Join Date: Aug 2004
Country: Canada
First Name: Rick
Posts: 767
 
Default

It's good to see the tips are being noticed... 1/2" shanked bits have more mass than the 1/4" bits and with mass comes the ability to dissipate the heat build-up allowing the router bit to stay sharper longer.

Rick and Bob
The Router Guys


Well I have just completed my first PDF E-Course, which is 10 embedded lessons from the Router Workshop Video Series. This is a must have PDF that you can get some very good pointers on how to use the router. Get your FREE copy here!

Click here to join the Router Workshop!!
BobandRick is offline  
post #3 of 8 (permalink) Old 10-13-2004, 03:45 PM Thread Starter
Retired Moderator

 
-Sam-'s Avatar
 
Join Date: Sep 2004
Country: United States
First Name: Sam
Posts: 639
 
Default

Oh, okay. That's good to know. Makes a lot of sense. Thanks a lot!
-Sam- is offline  
Sponsored Links
Advertisement
 
post #4 of 8 (permalink) Old 10-13-2004, 05:13 PM
Registered User
 
ejant's Avatar
 
Join Date: Sep 2004
Country: United States
First Name: Ed
Posts: 1,474
 
Default

Think of a flywheel, the bigger the flywheel the more momentum.


ejant is offline  
post #5 of 8 (permalink) Old 10-13-2004, 08:04 PM
Registered User
 
reible's Avatar
 
Join Date: Sep 2004
Posts: 1,702
   
Default

Quote:
Originally Posted by BobandRick
It's good to see the tips are being noticed... 1/2" shanked bits have more mass than the 1/4" bits and with mass comes the ability to dissipate the heat build-up allowing the router bit to stay sharper longer.
Here is something to think about:
"Making Tungsten Carbide
Tungsten and carbon powders are blended and carburized in a furnace at 2700 - 2800 F. This produces the WC grains.

These grains are combined with Cobalt powder and mixed in a ball mill. Tungsten carbide balls are mixed with grains allowed to run for several days to get even dispersal of the grains and the cobalt powder. This powder is then dried and wax is added as a binder. The wax holds the powder together and makes it somewhat slippery so it presses into shapes well. Typically 15 to 30 tons of pressure is used to form the carbide into a tool shape such as a saw tip. The parts are typically pressed one of three ways. They are rammed in a mold before sintering. They are isostatically pressed. Isostatic pressing means they are surrounded by a liquid or a gas and the pressure is applied to the liquid. This transfers the pressures to the surface of the parts uniformly. The third pressing method is hot pressing during sintering.

The shapes are presintered in an atmosphere-controlled furnace at temperatures of 1,000 - 1,500F. The wax melts out and leaves the pieces sort of like a soft chalk. These chalk pieces can be easily machined although they are also easy to break and can be chipped here if handled improperly.

The final step is another sintering step that can take place in a special atmosphere, a vacuum or both. The temperature is typically 2,500 - 2,700 f.

During final sintering the parts will shrink up to 15% in any dimension and up to 35% in volume. "

I have a feeling the heat issue is not going to hold up as a major issue in 1/4" or 1/2" shank court. At least in my opinion. I should also point out that carbide is often attached by way of welding or brazing both in the high heat areas compared to woodworking.

My guess is if they last longer it is in the vibration/deforming areas. But hey what do I know?

Ed
reible is offline  
post #6 of 8 (permalink) Old 10-13-2004, 09:08 PM
The Router Guys

 
BobandRick's Avatar
 
Join Date: Aug 2004
Country: Canada
First Name: Rick
Posts: 767
 
Default

As always there are many factors that make the sharp edges of Tungsten Carbide dull. Heat build up from friction, vibration, chatter, plus many other factors, which all translate directly into tool wear. Again, in my opinion: I find that my 1/4" shanked dovetail router bits will get dull sooner than my " shank bits.

Thanks Ed for the great information on Tungsten Carbide.

Rick and Bob
The Router Guys


Well I have just completed my first PDF E-Course, which is 10 embedded lessons from the Router Workshop Video Series. This is a must have PDF that you can get some very good pointers on how to use the router. Get your FREE copy here!

Click here to join the Router Workshop!!
BobandRick is offline  
post #7 of 8 (permalink) Old 10-13-2004, 11:51 PM
Registered User
 
reible's Avatar
 
Join Date: Sep 2004
Posts: 1,702
   
Default

Quote:
Originally Posted by BobandRick
As always there are many factors that make the sharp edges of Tungsten Carbide dull. Heat build up from friction, vibration, chatter, plus many other factors, which all translate directly into tool wear. Again, in my opinion: I find that my 1/4" shanked dovetail router bits will get dull sooner than my " shank bits.

Thanks Ed for the great information on Tungsten Carbide.
I emailed a request to one of the upper quality bit makers about this issue so if and when they respond I will post their responce.

Ed
reible is offline  
post #8 of 8 (permalink) Old 10-24-2004, 12:08 AM
 
Join Date: Sep 2004
Posts: 12
 
Default

Quote:
Originally Posted by reible
Here is something to think about:
"Making Tungsten Carbide
Tungsten and carbon powders are blended and carburized in a furnace at 2700 - 2800 F. This produces the WC grains.

These grains are combined with Cobalt powder and mixed in a ball mill. Tungsten carbide balls are mixed with grains allowed to run for several days to get even dispersal of the grains and the cobalt powder. This powder is then dried and wax is added as a binder. The wax holds the powder together and makes it somewhat slippery so it presses into shapes well. Typically 15 to 30 tons of pressure is used to form the carbide into a tool shape such as a saw tip. The parts are typically pressed one of three ways. They are rammed in a mold before sintering. They are isostatically pressed. Isostatic pressing means they are surrounded by a liquid or a gas and the pressure is applied to the liquid. This transfers the pressures to the surface of the parts uniformly. The third pressing method is hot pressing during sintering.

The shapes are presintered in an atmosphere-controlled furnace at temperatures of 1,000 - 1,500F. The wax melts out and leaves the pieces sort of like a soft chalk. These chalk pieces can be easily machined although they are also easy to break and can be chipped here if handled improperly.

The final step is another sintering step that can take place in a special atmosphere, a vacuum or both. The temperature is typically 2,500 - 2,700 f.

During final sintering the parts will shrink up to 15% in any dimension and up to 35% in volume. "

I have a feeling the heat issue is not going to hold up as a major issue in 1/4" or 1/2" shank court. At least in my opinion. I should also point out that carbide is often attached by way of welding or brazing both in the high heat areas compared to woodworking.

My guess is if they last longer it is in the vibration/deforming areas. But hey what do I know?

Ed
Wow, Great info. WOW.
Soozy is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Router Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
New Router my way reible General Routing 21 12-08-2018 11:06 AM
Mixing Bosch 1617 Router fixed base with Craftsman professional router sf_basilix Starting Off 17 10-11-2012 05:20 PM
Motorized Router Lift - Eagle Lake Style johnwnixon Table-mounted Routing 14 05-23-2012 04:51 PM
RouterForums.com and Oak-Park.com - September 2006 Contest - VOTING STAGE!! Mark Contests Archive 13 11-05-2006 02:23 AM
RouterForums.com and Oak-Park.com - September 2006 Contest!! Mark Contests Archive 72 10-01-2006 12:02 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome