# Parting Tool Question



## Ken S (Apr 24, 2016)

After binding and breaking the tool on my first parting attempt I've been afraid to try it again until I got a QCTP with a parting tool holder. I bought a grizzly parting tool to go in it, watched some videos, ground the tool properly (I think) and made my first attempt. I did get the piece parted but the tool pulled closer to the headstock as I got closer to center. I re-ground the tool, thinking it may not have been perfectly square and tried again. Some thing happened. On closer inspection of the tool, I discovered it is beveled at the top with the headstock edge being slightly taller than the other edge. Could this be the cause of it being pulled inward during the cut?
If so, how can I correct that?
Thanks
Ken


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## Wreck™Wreck (Apr 24, 2016)

Parting tools are often handed RH or LH, a straight tool will leave a a collar on the part which often requires a second deburring operation after it comes off of the stock.

Most likely your tool is a bit off in the X axis, use a dial indicator and adjust it as close as you can get and try again, indicate the blade itself not the holder nor the tool post.

A quick change tool post even if it is made by Aloris is not any more rigid than a 4 way, it is just more easily used. Many hobbyists seem to believe that "upgrading" to a QCTP will solve some of their problems, this is unlikely.


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## jeff_g1137 (Apr 24, 2016)

Hi
How old is the lathe, ???
set the tool slightly high of center, not low.
Tighten the gibbs slightly.


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## Ken S (Apr 24, 2016)

Thanks guys, I just put a dial indicator on the tool and got it within .0005 and tried another cut. Same thing happened. 
It's a 1989 Frehoth 13x36 I just bought it 3 weeks ago from the original owner who was a hobby guy and used it very little. I went home through it when I set it up and adjusted the gins but I'll check them again.


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## Ken S (Apr 24, 2016)

Gibs


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## Ken S (Apr 24, 2016)

This is the best pic I could get of the cutoff. Sorry about the sideways view. 

It's a real thin parting tool and can bend that much. When I face a shaft it's perfectly straight. The gibs are snug and there's no movement in the cross slide.


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## TOOLMASTER (Apr 24, 2016)

how fast are you spinning it....steel aluminum..stainless????


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## Ken S (Apr 24, 2016)

I tried again with the tool slightly high of center and it did the same thing. I can't figure this out.


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## Ken S (Apr 24, 2016)

I'm turning slow in back gear. 50 rpm I think. It's stainless. Also using oil throught the cut.


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## David VanNorman (Apr 24, 2016)

Do you have the T type cut off blade? The blades that have a bevel  top and bottom are made for the other style cut off tool  not the one for the quick change.


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## Bob Korves (Apr 24, 2016)

Make sure that your carriage is locked and that the blade does not protrude from the tool holder block any more than necessary to make the cut.  In your photo it is sticking out too far.  You need all the rigidity you can get.  Locking the gibs, as mentioned a couple times above. also helps with rigidity.  Especially if it is stainless, but always anyway, get the tool cutting with a chip curling off and then keep on cutting, keep that chip coming.  Do not be delicate about it.  Stainless especially will work harden if you rub it instead of getting under it and cutting it.  Work hardened stainless is just awful, avoid causing it.


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## Ed ke6bnl (Apr 25, 2016)

I needed to tighten the gib screws on the compound slide I found one time it was moving and take any slack out of it by pulling back.


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## stupoty (Apr 25, 2016)

Ken S said:


> View attachment 127703
> View attachment 127704
> 
> 
> ...



Dont put it to heigh, that would require the lath to flex and alow it to cut, i think that can cause some issues.

My best improvment i've had with hss parting tool is to use some small dimond laps to sharpent it.

I've been doing much better since i've started making it rediculouse sharp.

Stuart


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## Tozguy (Apr 25, 2016)

It looks like a tapered blade which can be tricky to align perfectly vertical. If the blade is not vertical with the same amount of relief on each side, it will push sideways. If the blade is held flat to the inside of a typical QCTP holder it will do exactly what you have shown. The blade should be shimmed out along the bottom of the blade to get it vertical.


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## Fabrickator (Apr 25, 2016)

Make sure your blade is sharp, squared to the chuck and the correct height, just slightly above center by about .010".  Length should be the minimum to clear the piece or live center if needed.  Make sure that you tool holder QCTP or otherwise is completely over the center on the compound.  Some run the compound at 30*, then they also find the tool holder is hanging over/off the compound.  You need to have plenty of support of the piece being cut.  Either chuck your work stub short or use a center. Depending on the material and diameter, cutting speeds could be from 50-150 rpm. Having your gibs adjusted properly goes w/o saying ...


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## LucknowKen (Apr 25, 2016)

There is a posting where a fellow was having difficulty parting with an off shore QCTP.
I think it was a Shars and the OP mentioned that the tool holder required shims to hold the tool in the correct position.


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## Ken S (Apr 25, 2016)

My thanks to everyone for your responses. I've checked and tried everything you guys have suggested except the shim.  It makes perfect sense that a tapered tool is going to lean out so i'll give that a shot tonight if I get a chance.
It is a tapered tool and I've been pushing it as tight as possible against the edge of the tool holder, not thinking about the taper.
It is a BXA import tool post I got from All Industrial with Hess tool holders. So far it's worked out great on everything but the cut off tool.

David, you mentioned a T top tool might be what works best in my holder. Should I look for a slot at the top edge for the tool T to fit in on the top side? If not, a T top tool would have to be shimmed also right?
Honestly, tool selection get's pretty confusing to me not knowing what I'm looking for sometimes. I can't thank you all enough for the knowledge you've imparted on this problem.


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## Billh50 (Apr 25, 2016)

A couple problems that also arise are that there are materials that will work harden if the feed is too slow and then the tool may suddenly dig in.


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## Bob Korves (Apr 25, 2016)

Fabrickator said:


> (snip)Either chuck your work stub short or use a center.


I learned to never use a cutoff blade for cutting off work between centers or in a chuck to a center.  At least not to cut all the way through.  You will pinch the parting blade, and that is never a good thing...


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## Ken S (Apr 25, 2016)

Billh50 said:


> A couple problems that also arise are that there are materials that will work harden if the feed is too slow and then the tool may suddenly dig in.



Thanks Bill, Bob mentioned that earlier and it's something I didn't know. I pretty much know nothing at this point but it's been fun learning.


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## Ken S (Apr 25, 2016)

Bob Korves said:


> I learned to never use a cutoff blade for cutting off work between centers or in a chuck to a center.  At least not to cut all the way through.  You will pinch the parting blade, and that is never a good thing...



Thanks for the info sir. After the first tool grabbed and blew up in my face, I gained a healthy respect for the process. I have a band saw that I've been using which works fine but I wanted to get back on the horse and learn. I figured out that using the powered crossfeed was much preferred over hand feeding. That seemed to be a much smoother operation and I can keep my head back out of the way too.


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## Ken S (Apr 25, 2016)

Bob Korves said:


> I learned to never use a cutoff blade for cutting off work between centers or in a chuck to a center.  At least not to cut all the way through.  You will pinch the parting blade, and that is never a good thing...



Bob, is that a wheel pedestal you're standing behind in your picture? I sold my boat a few years ago and my dear wife is pestering me to look for another. I do miss sailing.


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## Bob Korves (Apr 25, 2016)

Ken S said:


> Thanks for the info sir. After the first tool grabbed and blew up in my face, I gained a healthy respect for the process. I have a band saw that I've been using which works fine but I wanted to get back on the horse and learn. I figured out that using the powered crossfeed was much preferred over hand feeding. That seemed to be a much smoother operation and I can keep my head back out of the way too.


I have only used power feed a couple times while parting off.  It worked fine, but I was nervous and had my hand on the feed lever the whole time.  I like to feel the resistance to the cut, and the feedback gives me a good idea what is happening at the tool and work interface.  It is also instant to back off and regroup...


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## Bob Korves (Apr 25, 2016)

Ken S said:


> Bob, is that a wheel pedestal you're standing behind in your picture? I sold my boat a few years ago and my dear wife is pestering me to look for another. I do miss sailing.


Yes, a very nice sailing yacht, not mine though.  One of my old soaring buddies and his wife belong to a sailing club out of Port Richmond in San Francisco bay and he is an instructor there.  Sometimes I tag along as crew on whatever boat he has that day.  It is a fun and relaxing way to spend a day, and there is lots of time to talk and enjoy the ride.  The sailing is usually excellent on SF bay.  In all honesty I chose the picture because it is about the only recent photo I could find of me, don't much care for the H-M two letter default avatars...

Edit: Golden Gate Bridge above us in the photo...


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## Ken S (Apr 25, 2016)

Gentlemen, thanks again for the parting school. The shim did the trick. Problem solved. You guys have a good night, or morning in your case Jeff.


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## jeff_g1137 (Apr 25, 2016)

Hi
No problem
Jeff


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## Chipper5783 (Apr 25, 2016)

Glad you got it sorted.  For those wedge top holder (that are held in sort of a dove tail holder).  You may need to grind about a half inch of the top surface so it is flat, then keen that front face real sharp.

I power feed my part off jobs all the time.  One does have to feed at a decent rate - not too fast, not too slow.


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## Bob Korves (Apr 26, 2016)

I like the T shaped parting blades.


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## Ken S (Apr 26, 2016)

If I had a mill I would cut a relief in my tool holder and get a T shaped tool but alas... No mill. 
I'm planning on a trip to the Springfield, MO  Grizzly tent sale in June to hopefully find a deal on one.


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## Ken S (Apr 26, 2016)

I power feed my part off jobs all the time.  One does have to feed at a decent rate - not too fast, not too slow.[/QUOTE]

Thanks Chipper, I'm using the slowest speed with power feed and it does better than trying to do it by hand. I guess you go with what works for you.


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## olcopper (Apr 26, 2016)

You could do what many of us do, part it off slightly longer than your target length and face it to the correct length.
olcopper


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## dlane (Apr 26, 2016)

Carbide tip cut off blade, they actually work good if you sharpen and make them rite 


Not my pic ,


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## Ken S (Apr 27, 2016)

olcopper said:


> You could do what many of us do, part it off slightly longer than your target length and face it to the correct length.
> olcopper



LOL... Good advice and I've been cutting long all along anyway. Right now I have zero confidence in my ability to part perfectly.


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## Ken S (Apr 27, 2016)

dlane said:


> Carbide tip cut off blade, they actually work good if you sharpen and make them rite
> View attachment 127869
> 
> Not my pic ,



Hmmm... That's a clever idea. I have plenty of old saw blades stacked up that I never got around to sharpening. I like it!
Thanks


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## Silverbullet (Apr 28, 2016)

Your cutter is I bet bending downward or flexing causing the cut your getting. Make sure your tool and compound are not to far to the left of the table lock your table and tighten your Gibs then try your cut I bet it will improve greatly. Takes quite a bit of pressure to do a parting job on small lathes they just don't have the mass to absorb the bending pressure related to the cut. I use to sharpen my blades and make a small relief on top to make the chips curl easier it seemed to help a lot for me.


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## cathead (Apr 28, 2016)

Another way to use the saw blade carbides is to unsolder them and resolder to a parting tool.  Its easy to do
and saves the cutting and can be applied to a stiffer parting device.  Its done with a brazing torch,
flux, a bit of silver solder and relatively easy to do.


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## coolidge (Apr 28, 2016)

The Aloris #71 just saying.


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## Ken S (Apr 28, 2016)

[QUOTE="
flux, a bit of silver solder and relatively easy to do.[/QUOTE]

Wow, I didn't realize it was only solder holing those on. Thanks


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## Ken S (Apr 28, 2016)

coolidge said:


> The Aloris #71 just saying.



Yes, that's drool sliding down my chin. Maybe someday


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## cathead (Apr 28, 2016)

Ken S said:


> [QUOTE="
> flux, a bit of silver solder and relatively easy to do.



Wow, I didn't realize it was only solder holing those on. Thanks[/QUOTE]

It's called silver solder and has a tensile strength of between 40,000 and 70,000 according to Harris Products Group.  
Although called solder, it is nothing like the typical plumbing or electronic solders which are a mixture of lead and tin
traditionally.  Silver solders have a melting temperature of somewhat over 800 degrees F.   Silver solders are usually
an alloy of copper, tin and silver and is available in various mixtures of these metals depending on use and strength needed.


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## Ken S (Apr 29, 2016)

cathead said:


> Wow, I didn't realize it was only solder holing those on. Thanks



It's called silver solder and has a tensile strength of between 40,000 and 70,000 according to Harris Products Group. 
Although called solder, it is nothing like the typical plumbing or electronic solders which are a mixture of lead and tin
traditionally.  Silver solders have a melting temperature of somewhat over 800 degrees F.   Silver solders are usually
an alloy of copper, tin and silver and is available in various mixtures of these metals depending on use and strength needed.[/QUOTE]

Is it the same solder the HVAC guys use?


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## cathead (Apr 29, 2016)

Ken S said:


> It's called silver solder and has a tensile strength of between 40,000 and 70,000 according to Harris Products Group.
> Although called solder, it is nothing like the typical plumbing or electronic solders which are a mixture of lead and tin
> traditionally.  Silver solders have a melting temperature of somewhat over 800 degrees F.   Silver solders are usually
> an alloy of copper, tin and silver and is available in various mixtures of these metals depending on use and strength needed.



Is it the same solder the HVAC guys use?[/QUOTE]

Ken, 

Generally speaking, yes.  There are several brands available as well as manufacturers and product mixes.  Welding shops
carry this and also the flux.  By the way, the flux can be unhealthy if used in a closed space not to mention any silver solder
mixtures that contain cadmium as it can cause permanent breathing problems.  Fortunately most of the silver solders
do not contain cadmium any more.   Definitely read the labels and pay attention to any warnings on the packaging of both the solder
and the flux.


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## eeler1 (Apr 29, 2016)

I need a pic of the shim solution


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## cathead (Apr 30, 2016)

cathead said:


> Is it the same solder the HVAC guys use?



Ken,

Generally speaking, yes.  There are several brands available as well as manufacturers and product mixes.  Welding shops
carry this and also the flux.  By the way, the flux can be unhealthy if used in a closed space not to mention any silver solder
mixtures that contain cadmium as it can cause permanent breathing problems.  Fortunately most of the silver solders
do not contain cadmium any more.   Definitely read the labels and pay attention to any warnings on the packaging of both the solder
and the flux.[/QUOTE]


Here's a little more information on silver solder and flux.  I use a Harris product called Stay Silv which contains potassium
fluoride and difluorodihydroxyborate.  Fluorides as you may or may not know are some extremely reactive compounds
used in this case for "wetting" or maybe ease of flow would be another way to put it.  It's pretty difficult to do silver
soldering without the flux because the solder just won't flow properly.  Knowing about the products goes a long way
to its safe use.  Basically on the labels they say to not breathe the fumes or have skin contact or eat, drink or smoke
while using this product but they don't say why.  Now we know why.  To sum it all up, a little common sense thrown
in goes a long way to being safe in the shop.  Harris makes another product called Stay Silv 15 which is a silver soldering
rod.  I have used it but prefer the finer silver solder wire for small work.  The rod is pretty good for cementing carbide
on to various tooling like boring bars or lathe cutters.  Silver soldering is a good skill to have in the shop and found to
be quite useful when the need arises. 


On the less serious side, better living through chemistry! 

I had to inject a little humor, keep   in the shop, use your  , don't be a . 

Geez, these emoticons are fun!    Have a good day.


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## Ken S (Apr 30, 2016)

Lol... Thank you for that information. It sure takes the guesswork out of the decision.


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## Ken S (Apr 30, 2016)

eeler1 said:


> I need a pic of the shim solution



It's probably not what you expected but lacking any shim stock, I cut two pieces of paper and laid them in at the base of the tool. The results were a perfectly perpendicular cut.


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## eeler1 (May 1, 2016)

Whatever works!  Thanks for the picture.

I had (have) a similar problem, with the parting tool wanting to bend slightly into the work toward the headstock.  Actually switched to an older phase II holder that already had a tool, in it, worked fine.  Thought it must have been the tool that was the problem, or lack of ridgity in the compound or the like.  Never occured to me that it might be the tool holder!  I'll try the shim and see if it makes a difference.


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