# What a mess, what am I doing wrong?



## 100LL (Feb 24, 2018)

I got a little shop time today and I’m having a terrible experience.

I got in a piece of 6.5” round durabar (cast iron) to make a chuck backplate and first thing off I went to face it and turn it.  I have an aloris turn and facing tool with carbide inserts.  First time I’ve used it and I’m also pretty much a beginner.

Well, facing went ok.  Sort of.

But turning is terrible.  Tiny chips hitting me everywhere.  Sometimes a terrible screech.  Miserable experience.

I did look up the recommended feeds and speeds for the material and carbide inserts, and mostly tried to use that.  

What am I doing wrong? 

I took a video and some photos.


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## 100LL (Feb 24, 2018)

This is an attempt to post the video.
The piece is roughly 6.5” round and using the formula that called for about 650 rpm I think.  I dialed in more like 500 rpm.


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## 100LL (Feb 24, 2018)

Upload video didn’t work.  Put it on YouTube instead.


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## rgray (Feb 24, 2018)

Way to fast for me.
I would probably turn that at 100 surface feet per minute. That's 61 rpm Course I wouldn't use carbide either.
With carbide and approx 250 sfm rpm would be 150.
http://www.valleytool.net/calculator.php


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## 100LL (Feb 24, 2018)

I used this for my speeds and feeds
https://www.dura-bar.com/resources/upload/Dura-Bar-Machining-Guide.pdf

And then from there taking a broad shot in the middle:  800x3.28/6.5= 400 rpm


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## Ulma Doctor (Feb 24, 2018)

Hi 100LL,
nice lathe
the problem with cast iron is that it has a skin on the outside the you need to get under before it acts right and machines well.
the second problem i see is that you are attempting to use a facing tool for work on the od
put the tool on the front face of the toolpost and try again.
make sure the tool is on center


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## woodchucker (Feb 24, 2018)

No, the problem is you have your tool turned wrong possibly.
If you are turning from the tailstock to the chuck, it is  facing the wrong way.
The way it is in the pic, you would be turning from the chuck to the tailstock. You want put the holder on the other side of the qcp, and have the cutting end cutting into the workpiece.  Usually you want to turn toward the chuck so you are not pulling the piece out of the jaws. You can, but generally you turn toward the chuck. Most most of us turn toward the tailstock, with the tailstock engaged. Or for light cuts.

That's my take on it.


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## rgray (Feb 24, 2018)

100LL said:


> I used this for my speeds and feeds
> https://www.dura-bar.com/resources/upload/Dura-Bar-Machining-Guide.pdf



I think that is kinda production advertising & sales. I'm not sure 800 sfm for our hobby lathes will work.
Try it at half that speed...see if you like it better.
I haven't seen an insert like that either. something different there would probably help also.


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## 100LL (Feb 24, 2018)

I can’t quite get the cross slide far enough away from the work to turn it the other way given the size of this work piece ...I must admit that aloris facing turning tool does confuse me a little.
They market it like you pop it out and go the other direction and all of a sudden your facing instead of turning, but I just don’t see that.  Of course I’m a beginner.


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## Ray C (Feb 24, 2018)

Me thinks RPMs should be somewhere between 75 to 125 RPM depending on the grade and if you're using carbide inserts.  If it still has the hard outer skin, knock it down to 65 RPM and take several light passes.

Oh, and not only will you get hot chips on you, you'll need to do a lot of clean-up after cutting cast iron.  Messy stuff...

(Nice Lathe).


Ray


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## rgray (Feb 24, 2018)

100LL said:


> I can’t quite get the cross slide far enough away from the work to turn it the other way..



If you had a boring bar (3/4 or 1") and could put the holder out toward you to reach across the O.D. that may work better. Leave as little sticking out as possible.


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## dcsims (Feb 24, 2018)

Cast Iron has a very hard crust on it especially if it is Sand Cast which yours is not but it still has a hard crust that you have to get under with your first cut. Also your tool is facing correctly for a facing cut but when turning the OD toward the chuck you are turning off the end of the tool which may not have the correct relief for the cut. Rotate the tool post 90 degrees counter clockwise and turn with the other tool when turning the OD.

Durabar as you are using is extruded and cut to length so you will not experience the crust on the facing cut since that was cut with a saw but it will have a hard crust on the OD. Take a deeper cut for the first cut where the point of the tool is below the hard crust.

Cast Iron does product very small almost sand like chips so button up your collar and grin and bear it.

Good luck with your project.

Dennis


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## 4ssss (Feb 24, 2018)

Speed is way too fast, the wrong tool is in the tool post for that operation, and put a little more rake in the cutter.  The carbide is fine. If you try to use HSS, the cast will dull it as it's as bad as a grinding wheel.  What a lot of guys on here don't understand is that you don't need to consult a book to figure out surface speed and spindle speed, and any other speeds they can come up with because 1/2 the time it doesn't work anyway unless you're running a CNC machine, or all the little duckies are lining up in a row.  Everybody wants that micro finish, because they think that's the only thing that's key in machining.  If you drop the RPM and increase your cutting feed, you'll end up doing the same job, in the same amount of time, and with as good or a  better finish,  AND save your cutting tools for another job the next time you need them.  You don't have to run that lathe on the spindle speed, there's a thing on it called back gear, and it's there for a reason.  Give it a shot, drop that puppy into back gear and crank up that  feed rate, and don't be scared.  For every 100 RPM that that cutting tool is rubbing against the metal, you can be cutting metal 99 of those RPM's by moving that little lever on the gearbox to the next slot. As for the cast getting all over the place, use your safety glasses, better yet a shield, and a get face mask for your nose and throat, because your going to get it all over, and in you.  That's what cast metals do.


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## benmychree (Feb 24, 2018)

100LL said:


> I can’t quite get the cross slide far enough away from the work to turn it the other way given the size of this work piece ...I must admit that aloris facing turning tool does confuse me a little.
> They market it like you pop it out and go the other direction and all of a sudden your facing instead of turning, but I just don’t see that.  Of course I’m a beginner.


If you can't get the cross slide back far enough to use the holder as intended, back the compound outward until it does clear; if the gibs are sufficiently tight it should not move while cutting.


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## chips&more (Feb 24, 2018)

I have the very same Aloris tool holder. It will work as you have it set-up for doing the OD. But maybe not a cut deeper than the radius on the insert. I understand your lathe size restraint problems when trying to do the OD. As has been said many times, the skin is harder, you should cut underneath it. Even Carbide can have a hard time holding up to cast iron. It can have everything from sand to ball bearings in the pour. Maybe try the cheaper brazed carbide. Those triangle ones can get pricey. And the chip breakers on them too!


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## markba633csi (Feb 24, 2018)

Oh and another thing... LOL


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## 4GSR (Feb 24, 2018)

Tyler,

I started to ask you if you needed me to rough out that slug before I sent it. Sorry.  Like many said, get your RPM down to under 100.  Rig you up with a boring bar that you can sharpen a piece of HSS or Carbide and insert it into the boring bar.  That will allow you to turn down the OD.  Your Little Rockwell should be able to take a cut about .060" deep on the side and kick the feed up to around .025" rev.  This should get you under the hard skin on that material. That hard skin is about .090-.125" thick.  Also, you don't baby the feed rate on cutting cast iron.  Just put a broader nose on the tool bit when taking a finish cut.

Ken


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## Moper361 (Feb 24, 2018)

100LL 
This may help ease the frustration but i machined some cast iron a while back to make my radius tool .I went through exactly tee same as you on nearly the same curcumstances .A lot of the guys have said the cast has a very hard crust and this is just what i found when starting of on my work peice .In the end i slowed down as suggested and yes once tbrough the crust it was fine .The end finish i was happy with apart from having to clean the stuff of my lathe and out of my nose etc that dust is a real pain in the a#@%s and gets into places you would not believe .
You can see the pic of my radius tool its machined from cast as also shown in picture .


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## dcsims (Feb 24, 2018)

Yep Cast Iron is some nasty stuff to machine. My trade school instructor worked for a number of years in a Foundry and when he wore a white shirt by the end of the day he would have rust stains in the collar. The only thing I ever machined that is worse was carbon for EDM electrodes.

Dennis


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## umahunter (Feb 25, 2018)

Don't know  if you've got enough material to play with or not but if you do could he possibly take a grinder with a flap wheel and take off the hard outer crust then put it in the lathe and tru it up and cut on the softer material under the hard outer crust  ??? I know when I'm gonna cut hot rolled I either  soak it in acid first or grind off the hard surface to get to the softer metal underneath and spare my cutters especially since I have a smaller lathe  and mill and can't take those deep heavy cuts to get past the hard mill scale


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## 100LL (Feb 25, 2018)

Thank you all for the advice and comments.  I didn’t know Cast iron had those machining properties, and now that I do I never want to see it again.  What a terrible experience.  Dust and chips everywhere.  Such a pain to clean up.

Now I’m worried the dust and chips found their way into the apron and other gears/screws.  Ughh.


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## Chipper5783 (Feb 25, 2018)

Don't give up on using cast iron.  It is a good material for many applications.  Learning to machine it is like most any material - every material seems to have some unique issue.

As far as cleaning the machine. Yes, you'll need to do that.  Depending on the job, you can cover up parts of the machine to minimize ingress and every once in a while take things apart and clean them.   For covering up the ways & carriage, make sure what you use won't catch (use paper or aluminum foil), job dependent.


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## Buffalo21 (Feb 25, 2018)

I have one of the Aloris #16 lathe tools, that uses either the TPU or TPG inserts, I’ve never been impressed by the over all performance. I believe the tool is okay, but the overall quality of the available inserts, is the root cause of the poor performance. I’ve tried numerous grades and numerous manufacturers, with, little difference in the end results. I’ve  had much better results with CCMT and TNMG inserts.


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## 100LL (Feb 25, 2018)

You can see in at least one picture that I covered the taper attachment with brown paper (held with blue tape).  Crap still got in there.  And in my hair, and way over on the mill, and in my wife’s shoe closet upstairs and down the block on my neighbor’s truck.


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## tq60 (Feb 25, 2018)

First "step outside the box"...

Spin the tool post arround BACKWARDS.

Now get some brazed carbide tools...Just the cheap sticks but the largest that will fit your standard holders...The ones with just the slot. 

Place the holder on the tool post side now nearest to you then place it about 1/4 inch or so from the work (face side) and place it to where it can hold the cutter properly and away from work ( towards you) now place the cutter in the holder to where it can be just past work.

Now you have tool in right place to reach.

Use slow everything...low rpm and finest feed that you have as well as small depth of cut 

Carbide will work just fine on small cuts and you are pushing limit of machine so smaller cuts are needed.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk


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## Nogoingback (Feb 25, 2018)

100LL said:


> Thank you all for the advice and comments.  I didn’t know Cast iron had those machining properties, and now that I do I never want to see it again.  What a terrible experience.  Dust and chips everywhere.  Such a pain to clean up.
> 
> Now I’m worried the dust and chips found their way into the apron and other gears/screws.  Ughh.




Before you do anything else, use a shop vac to clean up the mess.  The last time I machined cast iron, I used the vac while
I was turning the part:  just sucked the chips away from the tool.  Aluminum foil works well to cover the ways as well.


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## bluechips (Feb 25, 2018)

From the pictures...
Slower rpm.
Use other end of that tool for turning OD.  You're asking for that tool post to turn and bury the tool into your work, you will not like that.
Move the chip breaker back a little.   About 1/8" from cutting edge.
Hold a chip brush on top of insert to minimize chips hitting you.  Don't let your lathe eat it.  Chips hitting you is part of this business... Safety glasses. chip shield?
One more time, If your tool post turns and tool buries itself into your work you're not going to like that.


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## 100LL (Feb 25, 2018)

Ok I’m trying to get my head around all the advice.

Consensus is:
Slower
Tool orientation
Get depth of cut on first turn

I think one advisor suggests setting up to cut in reverse?  I’ve seen someone turn the tool upside down and cut threads in reverse when there’s little/no relief at the thread start.  Is the advice to do that here for chip shedding control?

I got chips that were hot and flying, sometimes sparking.  A lot were forming more like a powder or dust.  One hit my lip and burned.  Then when the turning started to squeal I knew I needed to stop and ask.


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## 4GSR (Feb 25, 2018)

As I said above, slow your RPM's down, way down, use a coarse feed cutting cast iron, not a fine feed. That burns your tool up and creates all of that dust!  Not as much.  My bad, I should of offered to rought that out for you. Sorry.


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## rwm (Feb 25, 2018)

You can expect tons of black dust from cast iron. That is typical.
R


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## 100LL (Feb 25, 2018)

No prob Ken, this is a good learning experience.  I’m sur anyone with skill & experience would have made short work of this on an 11x36 lathe.  I know you’ve got larger machines and could have licked it in no time.  But in gaining experience it’s all about making mistakes, hopefully ones that leave no damage to person or machine.  

That’s the case here.  I got done cleaning up the mess.  Now to get things moving again.


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## rgray (Feb 26, 2018)

100LL said:


> I got chips that were hot and flying, sometimes sparking. A lot were forming more like a powder or dust. One hit my lip and burned. Then when the turning started to squeal I knew I needed to stop and ask.



Now think back on the great advertizing from dura bar. https://www.dura-bar.com/resources/upload/Dura-Bar-Machining-Guide.pdf

Kinda see it in a different light now...right?
It can be great stuff. But not always fun to work with. I use the vacuum method also to try and pick up the cuttings in the process.
Heck my Van norman boring bar has vacuum ability built into it from the factory.


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## 100LL (Feb 26, 2018)

This guy makes it look easy


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## Uglydog (Feb 26, 2018)

I like to cover my ways with some scrap cardboard when doing cast.
As stated above the swarf is more like sand and it seems to get into everything.
The more I can do to prevent keeping it out of sliding parts the less clean up later.
Consider tearing down your chuck or at least removing the easily disaasembled parts and cleaning that out as well.

Daryl
MN


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## Chipper5783 (Feb 27, 2018)

Here is an example of cutting something at close to the maximum capacity of the lathe - not quite full size (I can handle 21.5" and the wheel was only 21.25" diameter - cleared the bed by a whole 1/8").  You can see the compound is swiveled, the tool post is swung round backwards and I'm reaching out with a boring bar.  The bar had to be sticking way out in order to reach past the wings of the saddle, and past the flat portion to get to the flange.  It doesn't show up real well in the pictures, but the task was to remove the one flange from the idler wheel as it had worn - but not evenly.

The material is a cast steel, so not the issue with the black dust you get with cast iron.  However it was very rusty, and rust is bad news inside the machine.  The rust layer is also hard on tools (perhaps not as bad as the skin in cast iron), and because of about 1/2" uneven wear - there was no way I could get under the skin in one pass.  At my lowest speed (45 rpm) the surface speed is ~250fpm.  Brazed carbide is wonderful - I think I pulled the tool and touched up the edge every 3rd pass.  Rust is nasty stuff on the lathe bed too - so I covered the bed and cleaned up after.

The actual cutting did not take very long, the main challenge was setting up to hold the piece (pilots in each bearing bore, registering into the face place and then a ready rod through to the back of the spindle tube).  In all, the results was very satisfactory.

Good luck with your project.  David


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## markba633csi (Feb 27, 2018)

Chipper is that a gap-bed lathe? It must be- what model?
Mark


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## Chipper5783 (Feb 28, 2018)

markba633csi said:


> Chipper is that a gap-bed lathe? It must be- what model?
> Mark


Yes it is a gap bed, an Enterprise 1550 made by Mysore Kirloskar (India).  I've probably only had the gap out about 5 times.  They made a few different brands over the years.  I've had it a long time.  I find it a decent machine, it would not be considered a heavy pattern machine - but its made a good number of chips.


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## WarrenP (Mar 4, 2018)

I am learning here too, but isn't that a left handed tool when a right handed cutting tool should be used?


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## T Bredehoft (Mar 4, 2018)

You gotta do what you gotta do. Sometimes it just works out best that way.


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## bfd (Mar 4, 2018)

cast iron along with bronze will throw lots of tiny chips, to combat this place a brush ( paint, foxtail over the cutting edge this will keep the chips in one area. this will help bill


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## Silverbullet (Mar 6, 2018)

I have done a fair share of cast iron enough so it took two years to stop rusting my shirts from sweat. I used a slow enough speed and feed to not make spitting iron hot enough to burn. I used a slightly angled carbide with a small radius the carbide was made for cast iron. For finishing I'd use a high speed steel tool like momax. You have to adjust the feed to the finish no book or calculator can adjust it , I really enjoyed machining cast but I hated the after effects brown rusty skin and nose full of black dust. Besides the clothing. Your learning not doing wrong keep with it flat carbide tools don't cut cast they break it , it must have relief.


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