:wave: :wave: :wave: :wave: :) :) Hey Ya'll. Greetings from South Carolina!!!! I have a simple question for the machinist on board. In the picture below, what kind of cutter was used to cut these serrations? Also, it appears that the point at the end of each serration is due to the tool being lifted out of the cut at the end (I hope I described that right!). Would you guess CNC or master machinist and what kind of tools can be used???
Thanks in advance.
Bill

Looking at your picture?????, I would say they used dynamite. Quite universal tool.

Oops!

Minimal solution: pointed flycutter.

This was an included angle cutter. Probable a woodruff style end mill with the diameter to match the ends of the cuts, where when they stop the cut it leaves the pointed ends of the cuts. If it was a production piece, it was CNC. Can be done by hand by stepping over but much slower as the stop cut point will be different each line.

threadmill

Not ALL cutting tool are bought in the store, many old school machinists would prefer to free-hand a nice tool on a grinder, stone it to match a specific form or angle or radius! They can either be end cutting or horizontal side cutting single point tools, they usually cut with slow feed and speed but do the job most adequatly! It is a skill that should be learned by all machinists, and is rarely used in today's world of 3D automation!

The same cut can be done with a 1/16" carbide ball end mill (standard off the shelf cutter) and several passes at a time using high speed CNC machines to produce the desired form! So you can see there are many ways to skin a cat!

If you are doing a prototype, I would suggest the 1st procedure!
Eric

If you are doing a prototype, I would suggest the 1st procedure!

So that would be the dynamite?

threadmill would be the easyest and quickest , if you don't have one take a staight flt tap grind off the flutes except for one , two maybe three passes

Old school? Hammer and chisel? Chasing tools? And your not going to get a V notch with a ball end mill no matter how good you are. Just messing with you. The thread miller and and included angle cutter are regular off the shelf cutters. You could even grind the slots, as long as you want to use the grinder to grind your own cutters. Form grinding of these parts is a popular approch.There are lots of ways to do it. It makes sense to look for the fastest and easist methods.

I recall those type of cuts years ago with a small shaper.

don't see them much anymore

D-Bits from Micro 100, you can get them with a bunch of different included angles, we have them in 30, 60, 90, 100, 120 degrees, in a variety of diameters. You can get them from www.Travers.com

I would use on of two methods.
first would be to cut from the side with a small 90 deg (on a 45 deg angle of course) slot mill.
second and my favorite would be to use a 90 deg drill/mill and cut from the top. This however needs a vertical lead in/out. (I use mastercam for this)
There is another way also. You could tilt the part (or the head of the machine) and use a flat endmill. This is more difficult because the xy and the z positions change with every cut.

http://www.use-enco.com/ProductImages/8740569-11.jpg

The grooves in the product are clearly around 60 degrees. How are you going to make 60 degrees grooves with solution #13 & #14? How do shape the groove if the tool can't run out of the product? And what if the angle is between let's say 30 and 90 degrees?

Here is a toolbitholder (HSS). Here it is a cutter. If you grind the toolbit in the appropriate angle, which I'm not going to do for a photo, you have a nice one toothed circular saw. It gives the circular end for free. It reaches a nice cutting speed. As the stop points are all at a different position it was probably done with a tool like this. I think for once Widgetmaster and I are in agreement, sometimes it is much easier to make your own tools.

"Clearly" 60 deg. Good eye!!!
If the groove is 60 deg, then buy the 60 deg cutter instead.
It seem clear, to me anyway, that the actual angle isni't as important as the looks. Since Bill is going to make this his own (to avoid patent infringment) maybe these would work too.

"Clearly" 60 deg. Good eye!!!

I said clearly "around" 60 degrees, definite below 90. And I don't think a groove pattern is patentable.

I think the grooves in this case were cut with a conical cutter - similar to what Luke shows in his post.

Scott

60*

http://www1.mscdirect.com/CGI/NNSRIT?PMAKA=01787084

McMaster-Carr has 60* 82* and 90* end mills too...

Well gentlemen. The question:"How is it made?", has multiple answers. It's one-off against production. It's flycutter against pointed mill. It's standard mill versus CNC mill. It's type of mill(rpm). It's automatic generation of end point by flycutter against CNC'ed endpoint. It's the deburring needed, after these combination of methods combined with the material used, to get the "sharp" finish. It's oldschool versus newschool, or maybe general solution for everything, versus practical solution.
Regarding my experiences on this forum, I had to call in moderation this week, this is also an European-American discussion. So my goodbye is:"Do it anyway you want!".