# Lathe not turning properly



## benjames (Dec 22, 2013)

I was turning my first piece of metal, trying to part a piece of the end of a long bar when the metal just stopped turning. I am thinking that maybe I advanced the tool too far and it jammed.

 The motor was still heard to be running and now when I try and start the lathe it turns for a second or two and then stops and just makes a clicking noise.

 Can someone shed some light on what has happened?  I tried turning by hand to see if everything went back into place but it seems that I get one hard to turn revolution for every two or three easy to turn revolutions.

 I have posted a short video of the problem on youtube:

http://www.youtube.com/watch?v=GvFT6tPMsNI&feature=youtu.be

 Any ideas?

 Ben.


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## canadianhorsepower (Dec 22, 2013)

you could have broke a gear or
 check your lever at the back if its fully engage
 good luck


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## Tin Falcon (Dec 22, 2013)

Wow:

First of all Never part between  centers and never part with more than 2.5 times the diameter unsupported. 
Looks like the parting tool is too low. 

A bad setup likely broke the sacrificial gear. 

download a copy of army TC 9-524 of some other basic machining manual. Read up on the basics ask questions . 
And get a online or hard copy of the Machinery handbook. 
If you have a setup you are not sure of take a pic and post it here . We can help.

Looks like you should have just used a saw. 

Tin


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## benjames (Dec 22, 2013)

OK guys thanks.

 TIN:
 Is this the book to which you refer?
http://www.amazon.co.uk/dp/0831128003/?tag=skimlinks_replacement-20

 I have downloaded the army TC 9-524 and will give it a read.

 Luckily for me Luc was right when he said about the lever at the back not being fully engaged. I thought it was going as far as I could push it when I moved it to LOW but when I applied some more force it budged over more and clicked into place. Now it spins fine every time. I was moving it towards low and stopping at the resistance I felt.

 This episode has however been a wake up call for me to learn everything I can about each technique before I attempt it rather than learn all the mistakes myself.

 Thanks for your help guys. I got lucky this time!

 Ben


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## MachineTom (Dec 22, 2013)

You need a real parting tool, what you are using there looks like a chinese E type tool, that is used to weigh down scrap buckets. If the steady rest were moved to with an inch or 2 of the cut, you had a correct parting tool, and did not use the center, and back gear was fully engaged, then you would have been successful. 

Make Chips.


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## benjames (Dec 22, 2013)

MachineTom said:


> You need a real parting tool, what you are using there looks like a chinese E type tool, that is used to weigh down scrap buckets. If the steady rest were moved to with an inch or 2 of the cut, you had a correct parting tool, and did not use the center, and back gear was fully engaged, then you would have been successful.
> 
> Make Chips.



OK that's good to know, thanks Tom.


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## canadianhorsepower (Dec 22, 2013)

you were lucky this time around
 this hobby is fun but can be dangerous
 the download that Tim sugested is more than what you need
 after all their is 300 and some pages of information

 enjoy


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## Tin Falcon (Dec 22, 2013)

Well Ben IMHO no need to buy the latest edition. 
There used to be copies of the older editions on line . 
Just make sure you are buying the handbook not the companion guide unless you want both then buy both the guide is a textbook of exercises based on the reference book. 
The machinery handbook is a reference not a how to. It will not tell you how to set up a part but is will give specs and tolerance for every thread known to man . And it will give lots of speed feed info for many y many metals. 
It is not a sit down and read book but it has answers to lots of questions related to math engineering an machining. 
Seems like you should be able to find an old copy for 10 pounds or so. 

http://www.amazon.co.uk/gp/offer-listing/083112492X/ref=tmm_hrd_used_olp_0?ie=UTF8&condition=used
1914 edition
http://www.evenfallstudios.com/woodworks_library/machinery_handbook_for_machine_shop_and_drafting_room_1914.pdf
Tin


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## bazmak (Dec 22, 2013)

Parting off is one of the more difficult operations.Avoid when you can.Make sure everything is to the book
if you have part/off or deep groove and take your time


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## benjames (Dec 25, 2013)

TIN:
 Thanks, I bought that one. That was really cheap! Thm:

 BAZMAK:
 I will be much more likely to use a saw next time and leave the parting off for when it is absolutely necessary!

 Ben


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## Wizard69 (Dec 26, 2013)

bazmak said:


> Parting off is one of the more difficult operations.Avoid when you can.Make sure everything is to the book
> if you have part/off or deep groove and take your time




I tend to agree with this perspective.  However don't put those parting tools away, I often use a parting tool to cut a grove and then finish up with a hack saw or power saw.  This works out well with larger diameters and and difficult metals like stainless.   Of course
 you need to clean up afterward by facing but usually you have to do that anyway.  

Implemented properly, you can cut off smaller diameter stock no problem.  You don't want to eliminate the technique just because of one bad experience.    As others have mentioned feed rate and tool grind are very important.  You need to remember you are generally taking a fairly wide cut with the parting tool.  This means the chip load is significant.   So when it comes time to buy blades consider the thinner offerings.


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## benjames (Dec 26, 2013)

Wizard69 said:


> I tend to agree with this perspective. However don't put those parting tools away, I often use a parting tool to cut a grove and then finish up with a hack saw or power saw. QUOTE]
> 
> Would it be possible to make a sawing tool that you could put in the tool holder to save manual sawing?
> 
> ...


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## Tin Falcon (Dec 26, 2013)

what you are proposing is not practical. You can if you desire make a parting tool from a hacksaw blade or utility kine blade.  
Parting is  al little funny . Not hard takes some practice. a thin blade is easier because  less material is removed less work for the machine. But make it to thin the blade flexes an oscillates and then catches on the side and ugly things happen.  
Like any other tool proper hight as stiff as practical and clearance everywhere but where the tool is cutting. 
Tin


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## benjames (Dec 26, 2013)

Tin Falcon said:


> what you are proposing is not practical. You can if you desire make a parting tool from a hacksaw blade or utility kine blade.
> Parting is al little funny . Not hard takes some practice. a thin blade is easier because less material is removed less work for the machine. But make it to thin the blade flexes an oscillates and then catches on the side and ugly things happen.
> Like any other tool proper hight as stiff as practical and clearance everywhere but where the tool is cutting.
> Tin



Thanks for the info Tin. So would the above work if it was a hacksaw blade?

 Ben


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## Swifty (Dec 27, 2013)

The trouble is Ben, that you would be only working mainly on 1 tooth, fine until that wears and then the trouble starts.

Paul.


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## Wizard69 (Dec 27, 2013)

It has already been mentioned but the problem here is that only one tooth will be cutting and that tooth will quickly clog with chips.  




benjames said:


> Wizard69 said:
> 
> 
> > I tend to agree with this perspective. However don't put those parting tools away, I often use a parting tool to cut a grove and then finish up with a hack saw or power saw. QUOTE]
> ...


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## benjames (Dec 27, 2013)

ok, thanks for your comments everyone. Very helpful. I think I will stick to a hacksaw and vice.

 Ben. Thm:


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## Philjoe5 (Dec 27, 2013)

One point not mentioned is that when parting you are using a slow spindle speed (or should).  Your feed rate needs to be slow enough so the blade doesn't climb up onto the work.

Watch the tool tip.  You'll notice that the tool keeps removing material even when you've stopped advancing it.  Don't feed faster than the cutting allows otherwise something will break.

Parting takes a little practice, then it's fairly easy.

Cheers,
Phil


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## Philjoe5 (Dec 27, 2013)

Ben,
Don't give up on parting.  Although parting is not usually carried out with a center, there are times when you can use one.

Here I'm parting a water tank flange that's 0.157" thick.  Without the bull nose center I was getting a lot of chatter.  No surprise, there's a lot of work hanging out.  So I basically cut most of a groove 0.4" deep, removed the bullnose, and cut the remaining 0.020" slowly until the ring dropped off





It would be tricky to make this part with a bandsaw.





Cheers,
Phil


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## benjames (Dec 28, 2013)

Philjoe5 said:


> Ben,
> Don't give up on parting. Although parting is not usually carried out with a center, there are times when you can use one.
> 
> Here I'm parting a water tank flange that's 0.157" thick. Without the bull nose center I was getting a lot of chatter. No surprise, there's a lot of work hanging out. So I basically cut most of a groove 0.4" deep, removed the bullnose, and cut the remaining 0.020" slowly until the ring dropped off
> ...



 Cheers Phil. I guess being selective on when to use parting is the way I should go.

 Ben Thm:


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## Wizard69 (Dec 28, 2013)

benjames said:


> Cheers Phil. I guess being selective on when to use parting is the way I should go.
> 
> Ben Thm:




It will grow on you with experience.   Once you zero in on the right grind for the tool and the right speed you will find that parting off is very useful as long as you work within the limitations of the machine.


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## goldstar31 (Dec 31, 2013)

Ben,
If you recall, I suggested that you might benefit from going to the London Show at the Ally Pally.

Clearly you are now experiencing problems with parting off. Might I suggest that you read/borrow or steal either a copy of Model Engineer Volume 142 or George Thomas's Model Engineer's Workshop Manual? You could get a copy at the show. The latter contains how GHT developed a small rear parting tool and, importantly, how to make it- on a lathe. I made mine up many years ago and it has worked faithfully over many lathes. Currently, it is on a Myford Super7B which I restored some few years ago.
There is a kit of parts available from Hemmingway kits but it can be constructed from bits and pieces- and works just as well. Our old friend Dr Bill Bennett edited the posthumous writings of GHT into two books. They contain much information which is suitable for both beginner and the bit more experienced- but still learning- like me.

Norman

 In  a break before going to hospital, might I suggest that you Google the old Chris Heapy site. Again, there is lots of information- and this also recommends the GHT book etc


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## benjames (Dec 31, 2013)

goldstar31 said:


> Ben,
> If you recall, I suggested that you might benefit from going to the London Show at the Ally Pally.
> 
> Clearly you are now experiencing problems with parting off. Might I suggest that you read/borrow or steal either a copy of Model Engineer Volume 142 or George Thomas's Model Engineer's Workshop Manual? You could get a copy at the show. The latter contains how GHT developed a small rear parting tool and, importantly, how to make it- on a lathe. I made mine up many years ago and it has worked faithfully over many lathes. Currently, it is on a Myford Super7B which I restored some few years ago.
> ...



Hello Norman,

 I got myself a copy of George Thomas's Model Engineer's Workshop Manual and will have a look at the parting tool holder when I get a moment. Thanks for the heads up.

 Ben.


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## mikbul (Dec 31, 2013)

benjames said:


> I was turning my first piece of metal, trying to part a piece of the end of a long bar when the metal just stopped turning. I am thinking that maybe I advanced the tool too far and it jammed.
> 
> The motor was still heard to be running and now when I try and start the lathe it turns for a second or two and then stops and just makes a clicking noise.
> 
> ...


 
 I find it easier on the lathe and safer to start the cut with the parting tool then clamp it in the horizontal band saw. Then I come back and face it.


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