Dave_C wrote: ↑
Sun Jun 24, 2018 1:37 pm
I find them to be much sharper and provide a much better finish than HSS end mills.
I'll have to agree with Glenn, I've gone to all carbide end mills which are all made for specific purposes. 3 flute with special coatings for aluminum and 4 flute and a different coating for steels.
When I closed the doors on my commercial shop, I really hated the machines. I was burned out beyond belief, and didn't care if I ever saw the machines again. That was back when coated cutters were in their infancy, so I didn't grow with them. While carbide end mills were available, they were exceedingly expensive, so they were used only when absolutely necessary. I owned precious few.
Fast forward to today, where CNC cutter grinders are the norm, and carbide has been drastically improved. The cost of carbide end mills is often cheaper than HSS equivalents, so I've added several when the deal came along. I can remember when the market crashed and one of the makers was offering them in quantity at very attractive prices. I paid something like $4 each for 10, single end, ¼" diameter four flute. I like them, but I'm well stocked with HSS end mills, so the carbide end mills are still reserved for those occasions where they are required. Don't know if I'll ever get over my old habits!
I had some .200" slots to cut .500" deep in aluminum. Made with .125" carbide end mill, 2700 RPM, a little WD and shes good to go.
The extra benefit if carbide is the added stiffness, which makes cutting straight slots a lot easier. Given your situation, I'd likely do the same thing, especially if my old stock of HSS end mills didn't include a new, sharp one. The only difference is I'd run it faster, but only because I can. I can remember when my fastest spindle speed was 2,700 (my first Bridgeport). Can't use too much speed when running those small end mills. My setup with the worm tolerated 4,200 for the finish cut, and it likely would have taken more.
Not intended to get the thread side tracked so congrats Harold on the setup and the finished product. That's some pretty out of the box thinking! (The differance between a machine operator and a real machinist)
Thanks, Dave. First, no problem with side tracking. In fact, it's encouraged by me, assuming it remains within the confines of the intended purpose of the board. Wonderful gems of information are often disclosed by wandering, which I find to be quite useful. The only real problem with getting off topic is that it's hard to find information in a search by title. Can't see a down side beyond that. I'm certainly not concerned with anyone "raining on my parade".
As far as the "out of the box thinking", wish I could claim this as my own, but it's nothing more than a feature offered on universal horizontal mills. It's been done before, but the setup is somewhat limited without the ability to swivel the table. Still, it offers the ability to make cuts that, otherwise, would not be possible, even with a CNC unless it has the fourth axis. I had intended to make the setup some day, which is why I jumped at the opportunity to purchase the large lot of gears I acquired many years ago, while I was still building our shop and house. Never in my wildest dreams did it occur to me that I'd have need in restoring a fine old piece of equipment.
I hope this thread encourages others to pursue similar projects. After all, that's what we're all about here!