What type of cutter is this?

[ajc1112007]

Hello. I’ve spent some time searching online for info on these cutters to no avail. I bought these “end mills” the other day and once I receive them, I realized they aren’t typical end mills. These have the spiral reversed from the normal direction. They have 6 down-cutting flutes and no cutting edges on the bottom. I only really use the sides/periphery/circumference of cutters like this to face blocks on my mill, so no blades on the bottom doesn’t really bother me. I don’t have any other down-cutting tools for my mill..just some router bits for wood/plastic/etc. These cutters are made from M42 tool steel. It’s like a long, skinny face mill and arbor in one piece…something that I’ve never seen before. Anyone have any details to share on these cutters? Uses? materials that can be cut with it? Any reason(s) I should be careful using them? I don’t know - hoping to pick your brains, learn something, and maybe avoid any possible errors. Thank you for your time. Adam

 

[Steve-F]

Reversed Helix flutes.

 

[benmychree]

Made for profiling. Likely for aluminum.

 

[woodchucker]

In wood working we call that a down cut spiral... normal cutters are upcut. Same with endmills.

They have the advantage of keeping the wood veneers from splintering.
In metal they can be handy to keep the burr down, to force chips down through and opening that might have a greater cavity than going up, maybe.
The high helix is for moving metal fast, and preventing chip buildup. I have one very similar but in a normal upcut.

 

[ajc1112007]

Thanks for your replies. So I should be able to cut metals just fine. I don’t see a reason it wouldn’t…but the more I learn, the more I learn I have more to learn. I’d like to keep them for facing cuts on blocks where chips flowing down can’t really build up (off the side of the vise). These cutters can’t be better at this task or they would be more popular (you’d think). Thanks again.