Originally Posted by BrendaEM  "Why the predisposition to carbide?"
It was my hope that the factory ground edge on carbide would wear longer than HSS. I know that HSS could be resharpened, but for some time, I am going to lack the the equipment and skill to do sharpen an endmill, so I need the bit at least to be true and sharp--even if I cannot be.
"what are you machining?" Largely, mild steel, aluminum, and hard plastic.
I have several projects planned. I am going to be making some motorcycle/bicycle type drop-out parts. I don't know whether or not I'll go with steel or aluminum. I am going to make some front vehicle suspension type parts, They will be steel.
I have some other little projects I want to make, some optic holders: mirror and beam splitter holders, who knows maybe even a spatial filter. I may be tempted to lighten my bike a bit, which may have anodize on parts. Lastly, I may help a friend make a boat-accessory from stainless, but I know whatever good bit I use for for, won't be good for long. I need to look into some kind of coolant situation.
I had planned to get just a few sizes or endmills say, 1/8", 1/4", and 1/2" in carbide, but perhaps I should get a set of TiN HSS too, if not for in-between sizes, but for practice. The TiN might be slicker than the carbide for aluminum. |
With the execption of stainless it sounds like you really only need HSS. I don't know what you are meaning about running true with a milling cutter, they very rarely run true after the first time you dig into something. I could only see that being a problem if you were doing some sort of form tooling like a V or radius on a filltet. The fact of the matter is that mills get clogged and when side cutting you will get smaller chatter marks, this is more pronouced on smaller less rigid mills and with smaller end mills. As for sharpening end mills its not impossible to send them out to be resharpened, esp when you buy that 1" monster that you need for the odd off job. But I don't feel bad about throughing away a $5 1/4 endmill at work either. The person that does all my current lathe work has been doing my resharpening of HSS Tin coated mills for my personal stock to use at work. He charges me based upon how long it takes him, the most i have paid is $10 for a set of 5 and the edge was superior to the new edge.
Also don't shoot yourself in the foot when you buy endmills buy them by the dozen or half dozen. There will be something that will not go your way some day and you will either crash, or break end mills sometimes right in a row.
chris