Ab Tools/tormach Shear Hog Inserted End Mill

JimDawson said:
John, that is absolutely correct. But....you have to adjust the feed speed to match the cutter speed so the chip load stays in a reasonable range. Too little feed and the cutter is rubbing, not cutting. Too much feed and the chips are too thick and your machine is bouncing around.
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Jim, you got me to thinking about this some more. Given that my max spindle speed and feed rates are relatively low then it might turn out that a HSS roughing end mill will work better than an inserted carbide tool. If I get a 3/4" roughing end mill and bury it in the cut I can maintain a decent chipload that will give a decent tool life at the feeds/speeds I have available. I am feeding manually so it will be done by feel and ear. I guess I'm saying that I'll be using chipload in place of high spindle speeds to do the work.

I will see what Tormach has to say but now I'm thinking that this might not be the right tool for this machine.
 
I heard from Tormach this morning:

Typically, we run the shear hog around 5000 RPM because it is specifically designed for high speed aluminum machining. It probably could run at 2500 RPM but the feedrate would need to be reduced and the capability of the cutter not fully utilized.

So, pretty much as we've discussed. Now I need to think about if my curiosity about this tool is worth the cost. A good roughing end mill for aluminum costs about $40-50 a shot in cobalt but a single insert would probably outlast that and then some.

If I decide to buy this tool I'll write a review.
 
Well it's been over a yr and a half and no review probably means no purchase? After the CNC conversion of my RF30 I'm looking for better tooling for it, the shear hog looks so good but like you I'm wondering the same exact questions. What roughing endmills do you like btw? I think I have a 1/4" Niagra...again looking for recommendations on tooling that works well without breaking the bank.
 
I decided to be realistic and not buy the Shear Hog. I agree, it looks really good but not if my mill cannot get up to the right speed. I realized that if I cut with it at too low a speed then I will be asking for deflection from that steel shank and that would cause accuracy and finish issues. For the cost of that tool, it just didn't make sense to buy it just to do stock removal in aluminum.

I use the Tormach Superfly for stock removal and squaring and it works really well for that. I don't like that it cannot cut to a shoulder, though. I also use a Sherline inserted carbide flycutter for smaller pieces or when I need to cut a shoulder. It is only 1-1/8" OD but it is essentially a single insert face mill that works really, really well and produces a better finish than the Superfly does. I stuck the Sherline tool into a 5/8" shank with an internal 0MT to accommodate the tool; works good.

I prefer Niagara roughers, 2 or 3 flute for slots and pockets and 4 flute for profiling/external cuts. I use coarse pitch for slotting and fine pitch for profiling. I use HSS most of the time, cobalt for harder steels and carbide for when I have to go deep in a pocket or have a long external face to rough. Buy your stuff on ebay and only buy new end mills; used stuff is a waste of money.
 
Thanks Mikey, great feedback! The Superfly is also spendy but not as much as the Shear Hog. I'll have to look into the Sherline flycutter. Between those two what's your main go to tool?

Then there are 'Little Hoggers' I think made by Accutime or something, that I've heard are pretty decent. Currently I have a set of generic fly cutters (without bits, because I suck at grinding bits), and a 4" face mill with dull bits. I was thinking about using one my lathe carbide insert tools (left hand tool) for the flycutter, I've heard people have had good results with that. In my case though the lathe's tool bits are 3/8" and I think the flycutter's is 5/16 so I'll have to take off some material from the tool bit which isn't really a big deal.
 
I think I use the Superfly more nowadays but both are useful. Depends on what you're doing.

You can buy a simple LH brazed carbide tool, sharpen the carbide and put a nose radius on it with a diamond stone and you'll have a decent flycutter tool without having to grind one. It works, too.
 
Just tried out the carbide lathe bit...worked quite well actually. I'll post the video/pic in the POTD thread.
 
I bought two, TTS shank shear hogs about the time of the original post. One 3/4" diameter one flute, the other 1-1/2" two flute.
I have only used the one flute, and experienced some issues with tool pullout. New machine, green operator, I did increase the tension on the spindle collet. My feeds and speeds calculator does not support this tool.
The 1-1/2 horsey tormach might not be able to pull two cutters.

I can report that one flute will remove a lot of aluminum at 5100 RPM.
 
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