What's new
What's new

Tool gashing

1Newbie1!

Plastic
Joined
Aug 13, 2019
Need help understanding what I'm doing. First question some of corner radius endmills I make have conventional gash others have radius gash. Why?
 
I don't understand what is so special about radius gashes, ball nose tools are worse. So I figured I wood start simple and move to harder stuff next.
 
The gash is what the grinder hand or the manufactures has gotten into the habit to make. Both work ok . I like to run a little over a 1/32 radius with Norbide stick and eye-ball dressing the wheel.

One flute to center and the others cut out works fine also.

Split point drills are cut in sharp corner, and radius and they both work fine.
 
I made a 3/8 endmill with a .06 thousand rad with a radius gash, then made a 1/2 endmill with a .06 thousand rad conventional gash. I am trying to understand why one was gashed one way and the other a different way?
 
Confused.
Are you running a grinder for a shop and wondering why the different type cuts?
I'm wondering if what you call radius gash is what others would call a radial gash.
Probably pictures not allowed?
Bob
 
If you are referring to the "gash" behind the leading edge of the cutting flute on the bottom of the endmill, there is a lot of variation within the industry. Many "high end" endmills have a very aggressive gash angle in order to prevent loading up the endmill on deep slotting and aggressive helical entries. It gives a place for the chips to evacuate during the cut. The down side is that this drastically weakens the tip area. Usually not an issue, but there are times when there are little pieces of material that go out as a chunk, rather than as chips (last little bit on a high speed toolpath, cutting around the OD etc.) If you have that situation, eventually you will bust off one of the flutes on your new fancy endmill. If you have a very refined toolpath that requires aggressive ramping, a large gash angle may be an advantage. But if you have a chance of kicking out a chunk of material as a slug, it may cost you money over the long term.
 
Yes carbide Bob I think it is called radial gash and also helical. G00 proto if I understand what you typed the gash is only for clearance. When gash comes up to where radius meets od on corner radius endmills not to make radius true just clearance.
 
I’m definitely weak on my endmill terminology, and how the subtle changes in the grind geometry impact performance. Seems like stuff I should know by now. Anyone ever seen a book or webpage that delves into the subject? Machinery Handbook is a bit sparce.

8f31a2e98cc2cccd352ad6db7cc42660.jpg

e60c115caeb7568e02bd29450f28ef36.jpg
 
I found same stuff online, but it doesn't describe what I am looking for. Thank you for trying to help me.
 








 
Back
Top