Cut off tooling??

S

skeetlee

Active member
Just curious as to what type of cut off tools you fellas prefer? I have killed two of my dads kennametal cut off tools, and i really dont know why, or how i did this. I must have not been 100% square to my work?? Anyway, i will replace these tools for him, but i think i may try and find a different alternative for myself. His cut off tools were " notice i say were" insert v type tools. I ripped the hole dam head right off the small one. Heck it was even cutting good right before it happened. I was going slow as well. 60rpm to be exact. i dont know what happened!! I just dont care for that type of tool, and i would like something a bit more robust. Any ideas? lee
 
hieght is most likely the issue.
the work will try to climb the tool if set to high.
play in the head stock bearings.......allow it to climb also...

i use "std" straight cutoff stock tooling in a holder..not inserts. sides are ground for clearance, top 1/8 or so is full size, grind at 90 degrees and shallow relief below.

i have limited experience there so hopefully others will chime in.
mike in co
 
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My GO-TO cut off tool is a Dewalt resiprocating saw. I have a Grizzly G4003 lathe and I have broken a couple HSS straight tooling in a holder attempting to cut off 1.75" C1144. The events were just as mike in co stated, the work climbed the tool and "bang"... broke tool. I now use the HSS cut off tool to "grove" my work and finish the cut with the Dewalt or a hacksaw depending on the material. I don't think I can work the speeds and feeds required for those insert type tools to properly perform. I'm sure rigidity of my lathe (lack of) may have played a part too. As the tool grabbed the work, and before I could back out, I watched the tool post flex down towards the cross-slide and it was over... all in a fraction of a second.
 
Something you may consider. Although your lathe can be used with cutoff tooling, its also possible to damage it.
Your lathe is the same model that I use. That wonderfull large hole thru the spindle has a thinner wall than a heavy
lathe would have. When that tool holder takes a dive, the spindle can also climb and sometimes it doesn't recover.
Many of the parts in a Jet lathe are not heat treated, just machine steel, so go easy my friend. You don't want to
replace a spindle.
 
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I tried using the insert tooling on my Jet lathe and had major issues also. I kinda gave up on using any type of cutoff tooling at all on my lathe. I tried using the cheap cut off holders and blades that came with the lathe when I bought it used and had the same type of issues. Yes I had tried lots of different techniques when using them to no avail. I then decided to try some GOOD quality name brand cut off blades. WOW!! What a huge difference.

I can't say for sure this will cure all of your problems Lee, but it might be worth a try. I can't remember right now what brand they are but I bought them on _bay. I got a deal on about 15 of them for about $20, that's about what they cost each in the industrial catalogs.

I'm sure Jerry would agree that these small lathes just can't utilize the carbide insert tooling, they aren't rigid enough. I have started using a lot more HSS tools just on Jerry's advice. Yes you have to sharpen them but that isn't all that difficult.

Joe
 
Cutoff tooling is the hardest to use IMO. I've got ten different setups and just avoid the issue when possible. Bob makes a good point, it's hard on the equipment when it all humps up like a monkey on a football.

al
 
I'm not familiar with your lathes, but on mine Parting was very hard af first to learn, but once I figured it out it's a SNAP, well not anymore anyway. There were a few snaps though. I use Iscar insert tooling GFN sized 3mil width top lock inserts. I use three grades of carbide, one for harder steels is ic328 the one for Aluminum I use is ic20, and the stainless and softer steels do well with ic908. Plenty of fluid right on top of the cutter as it feeds in slow at first. On my lathe you can't change the rpms as you cut unless you stop and switch gear and start again, but I can change the feed in rate. I start most often at 350 rpm on rounds up to 1 1/2 inches at .001 in feed rate and the chips make a nice curl to the right as the come out. When the chips start bunching up I know i am not feeding in fast enough so I grab the next in feed gear, I keep doing this everytime the chip start to bunch. As you get closer to the center your surface feet per minute go down, so for the tools to work you have to increase either your rpms or your infeed rate. I choose infeed because my lathe handles it well. It is also important for the tool to be exactly centered for parting. I should also mention part as close to the chuck as you can, rigid is good.

Paul
 
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Parting tools are as many as burrs in a mules tail..... most are not very good....I use an Aloris carbide insert unit.Best I`ve used.... even so.... it must be set-up carefully.....just a touch... below center....
Most people run parting tools way to slow.... and the chips build up in cut-off groove......that`s what causes the problem...............then snap.....
A combination of feed/speed and tool tip chip curler all have to be co-ordinated to get chips outa groove....
bill larson
 
Thanks fellas, I was a little hesitant about even posting this, but i knew in my mind i was doing everything i knew to do to avoid braking this second tool. After i broke this second tool, i knew it was time to speak up. These kennametal parting tool holders are about 140$ a whack. When dad comes into the shop this AM i better have a good reason why we are down 300 bucks in my mistakes. All part of the curve i assume. I use my lathe ever chance i get and i can see were this little machine is lacking in rigidity. Actually it has me concerned a bit. I have often thought about replacing the junk stand this lathe sits on, but even at that i am not sure anything will improve? I am a fairly good welder and it wouldn't take much to make a good strong stand out of steel. I just dont want to throw good money to bad. Perhaps its best left alone?
I have also noticed that i have to turn at a high rate of speed to get any kind of finish when using carbide tooling. Not a big deal i guess, but very true none the less. Maybe that is common of any machine? I dont know, i will just keep on keeping on and learn as i go. Maybe in a few years i can afford a better unit. Lee
 
skeetlee said:
Thanks fellas, I was a little hesitant about even posting this, but i knew in my mind i was doing everything i knew to do to avoid braking this second tool. After i broke this second tool, i knew it was time to speak up. that is common of any machine? I dont know, i will just keep on keeping on and learn as i go. Maybe in a few years i can afford a better unit. Lee
Click to expand...

Skeet, temember the pictures I sent?

Remember what I said about insert tooling and itty-bitty lathes?
 
I have read in some of the model making article's about placing the tool upside down, and cutting from the back side of the work, I have never done this. The compound slide is designed to have the cutting force's down, not pushing up. My cut off tool is a hacksaw, or bandsaw. I have got by with going in a short way's, withdrawing the tool, and making another cut beside the first. Most all of my work is done with high speed steel cutters.
 
In our shop, we use insert carbide cut off tools on just about everything, lots of RPM and coolant is the key.

But most small hobby lathes do not respond to this, so the single blade HSS cut off tools work great. If you do not have an Aloris style tool holder, invest in one. Aside from a 3-jaw "Buck Chuck", I can't think of a more user friendly tooling choice for you lathe.

If you can't afford a actual Aloris or Dorian holder, the Chinese knockoffs will work, they just will not take abuse.
 
Skeetlee,
I think you are getting closer to see that the small lathe thrives on HSS tooling. Carbide requires Horsepower and
ridgidity. The small lathe does not have that. It does quality work, but not at a production rate that carbide was designed
for. When you crash, your also not out $300 bucks. I do use carbide for threading sometimes. My cutoff tool is HSS, hand
ground with lots of side clearance. Ground from a blank, I just may have $8.00 in it and it has lasted more than 20 yrs with
a bit of sharpening.
 
jackie schmidt said:
But most small hobby lathes do not respond to this, so the single blade HSS cut off tools work great. If you do not have an Aloris style tool holder, invest in one.

If you can't afford a actual Aloris or Dorian holder, the Chinese knockoffs will work, they just will not take abuse.
Click to expand...

Sorry, me, being the normally agreeable type, would not recommend the Aloris type holder for a cutoff/parting tool. Why? The Aloris type cutoff blade holder holds the blade on quite a bit of overhang OUTSIDE the boundary of the cross-slide ways. So, while the cutting force is pressing down on the left cross-slide way pressure is about neutral on the right way, most of the time. As a cutoff/parting tool is cutting sometimes it will tend to grab and when this happens pressure is then upwards and WHAMMO, another tool done gone!!

Hows best? get yourself a lantern type cutoff holder. This positions all the load downward between the cross slide ways. Do not use the lantern rocker-type base, instead, block up solid with a piece of tool steel of sufficient thickness to bring the cutter on center.


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Jerry's method is just fine but I use an Aloris BXA #7 holder with a T-type HSS blade. You only need to grind the front clerance. Keeping the overhang to a minimum and going slow with plenty of coolant is necessary. It has worked well for me at least. I pretty much use HSS for all turning and threading as well as cutting off in my shop. Carbide really is at it's best with larger machines.

Joe
 
Dad fessed up this morning that he himself has broken a couple of the parting tools, that i broke this past week. He has a couple Monarch lathes at work that he gets to play with everyday. He has broken two of these parting tools in the last 25 years. LOL!!
 
Anyone who can do cut-offs without snapping off tools has my undying respect and admiration. When Al Gore invented the lathe I don't think he included cut offs as one of the functions.
 
Holey crap, good point Jerry....


Remember this Skeet.......... many of the experienced tool men know better than anyone how to accommodate small "cheap" lathes because they've used them, for many years. The big argument about "American" VS "foreign" often overshadows the real issue. The REAL issue is simple, money.

When you're old and rich you can buy a hunner't thousand dollar car maybe......... But us young'ns just need a car to get to works so's we can afford our car. We own small flimsy lathes because THAT'S WHAT WE CAN AFFORD!


For 20-some yrs I let this hold me back. I paid others for YEARS because I was convinced I couldn't do quality work on equipment I could afford. Nor that I could really be SAFE just working willy-nilly. Oddly enough this is important to me, I've got 20 people depending on me NOT to cut my finger off... ((I don't SKI fer cryin' out loud...)) I finally got to the point I couldn't pay anyone to do what I wanted, (I don't mind being SHOWN I'm off on the wrong tangent but I get real pissy from being TOLD I'm an idiot.. :) ) so I fired up my cheapo chinese lathe that I'd owned for 5 years without really using. It was a pleasant surprise to find out that this piece of junk lathe is in fact much BETTER than 4 of the 6 lathes I learned on! The other issue in my case was time.... I'm in construction like you. Work finally got slow so I could spend several weeks with my lathe, setting it up, dialing it in and getting my mind right and my groove back and most importantly learning the capability of the machine in my hands. I only cut myself once, didn't hit the nerves and learned my lesson again, cheap.

But I got the thing up and running.....

Keep in mind I'm not doing production work.

Nor am I using the lathe to make money, nor even to SAVE money. I'm doing it so's I can do it the way I want it. And when I am down there in the mindless bubble that is running a lathe it's like a little Fortress Of Solitude, I DO so enjoy it.

but enough of my rambling,

al
 
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al
It is one of the most enjoyable experiences i have had in my life. heck i think i like playing with my lathe as much as i do my rifles. Maybe??? I like them both very very much, and now i get to include one with the other. life is good! Off to watch my daughters perform there cheer leading routine. They both are on a comp cheer team, and i enjoy watching them very very much as well. Good day gentlemen. Lee
 
On my SB 13" Lathe I've used HSS blades on the old Rocker toolpost at the slowest backgeared speed. No problems, but slow as hell.
With the Dorian carbide inserts toolholder I did break one blade holder, but the insert was still intact. I found out what Jackie already knew. Get the RPM's up, plenty of coolant and feed it slow. Zipping right along now. When it comes to lathes and mills. Bigger is always better. Glad I bought once and haven't looked back. There's also something to be said about those old SouthBend spindle bearings. Solid!
 
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