# Parting is no longer such sweet sorrow.



## savarin (Aug 16, 2017)

I have just tried out a "T" shaped parting blade of 1.6mm width on my 9x20 lathe, QCTP and a plinth not the compound slide.
Admittedly it was on cast aluminium about 2+ inches in dia but the ease and speed it went through was like a hot knife through butter.
You can see how much hang out I had on the blade and there was no chatter. I didnt even hone the edge, its just as I received it.
I am so impressed at its ease of use that I just have to say if youve never used one try it.
This is just as it parted, I started dry, the black marks are from when I decided to try a bit of wd40 then I finished dry.


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## richl (Aug 16, 2017)

Can we have a bit more info, I am not familiar with this tool.

Thanks
Rich


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## savarin (Aug 16, 2017)

This is the one I purchased.
http://www.eccentricengineering.com...wse&category_id=23&Itemid=3&vmcchk=1&Itemid=3


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## benmychree (Aug 16, 2017)

T type parting blades are definitely superior to the regular tapered type!  I have been using them for over 50 years; they have much less tendency to drag than the tapered type, which is the undoing of many attempts to part off.  An old friend and mentor (30 or so years older than I ) told me back in the day, that threading was usually the hardest thing for the beginner to master, and parting a second; he qualified it, saying that threading got better with experience, but parting, never did.  Perhaps that was a bit of an exaggeration but there is a ring of reality to it.  I think the biggest improvement in my success in parting over the years was when I bought an Aloris set of QC tools for my (then) 16' swing American High Duty lathe of 1916 vintage; it made a world of difference and partially paid for itself in fewer broken blades.  Prior to this I used Armstrong holders in the typical lantern holder with wedge and ring; the tool would hang up, the wedge would slip back in the ring, causing the tool to go more sideways and break; I improved that situation by making a solid ring the proper thickness to bring to tool right on center, and that helped lots, but the ridigity of the QC holder made even more improvement; I later sold the lathe, kept the QC set, and am still using it on my 19" Regal Leblond (and breaking even fewer blades!


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## q20v (Aug 17, 2017)

savarin, did you get the FoR tool holder as well? You mentioned you used the 1.6mm blade, did you order other sizes for different materials, or do you think the 1.6 is generally good for most stuff?


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## savarin (Aug 17, 2017)

q20v said:


> savarin, did you get the FoR tool holder as well? You mentioned you used the 1.6mm blade, did you order other sizes for different materials, or do you think the 1.6 is generally good for most stuff?


No,  as to your second question I have no idea. So far its worked on that chunk of aluminium and some 16mm stainless. With the stainless it started to chatter but as soon as I applied feed pressure the chips came off in smooth tight curls.
I used minimum stick out with the stainless.


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## GoceKU (Aug 17, 2017)

35$ for one blade is a bit expensive.


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## richl (Aug 17, 2017)

I did some looking after savarin posted here, I am frustrated by the results I have been getting, so naturally anyone claiming to have some success is going to get my attention.
I found other sources for the blades, they seem to be in the 18.00 range for 11/16" x 4" 3/32";  1/8" a few dollars more. I assume any t blade is the same as these?

Not looking to buy into any new systems right now, will the t blades work in my standard cutoff holder that comes with my Lathe? Do I need to modify anything?

I'm willing to buy a couple blades to see what they can do for me. I use mostly steel 1018, 1045 mostly. Lots of mystery metal.

Thanks
Rich


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## savarin (Aug 17, 2017)

GoceKU said:


> 35$ for one blade is a bit expensive.


27$ US and yes it is a lot but if it solves a heap of problems then I think its worth it.


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## DAT510 (Aug 17, 2017)

Shars carries T type parting blades starting at around $11, for M42, depending on width.  Cheaper for HSS

http://www.shars.com/media/flip/master/mobile/index.html#p=67


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## dpb (Aug 18, 2017)

On my 1440, I use a Shars .125" HSS parting blade and holder, in a BXA toolpost.  I run 100-150 rpm, with about .0045 / rev feed on the cross slide.  Just enough blade stick out to make the cut.
Thus far, from plastic to 2.5" 304, parting has been entirely drama free.


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## GoceKU (Aug 18, 2017)

Savarin, here i can buy carbide insert parting blade tool and couple of boxes of inserts for that price, and for the hard steels i'm using carbide makes more sense, last insert cost me 2$ i already have over 100 partings with it and still cuts great and i have another fresh side on it, so in cost comparison carbide is the way to go.


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## BGHansen (Aug 18, 2017)

savarin said:


> 27$ US and yes it is a lot but if it solves a heap of problems then I think its worth it.


Hi Savarin,

Like you mentioned, costs a little more than you'd like to pay, but how much is your relief from the frustrations of parting worth?  I have to admit to starting to throw money at stuff to make issues go away instead of dealing with cobbled up, wanna be "fixes".  Just spend the money (I've always had good luck with Shars and have a couple of their T-shaped blades) and make the problems go away.  Work on the project instead of working on the work-around for the project.  No to belabor it, but it's been said many times over that you can always make more money, but you can't make more time.  Great fix for your projects!

I've spent a fair amount on parting stuff; GTN-2 & GTN-3 tools, HSS with tapered sides and the Shars "T" shaped, MGMN bits, etc.  I have no issues taking on a piece of 1 1/2" O1 or 304 in my lathes.  Worth every penny for my options.  I've recently been using the MGMN bits more because they work well and are dirt cheap.  You can get 10 2-sided bits off eBay all day long form under $10.  Usually go to the T shaped HSS or GTN-3 for larger stuff, always dust the HSS on the bench grinder before parting (Tom Griffin of Tom's Techniques tip).

Bruce


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## Doodle (Aug 18, 2017)

I have a 9 x 20 HFT lathe and have problems parting. I stiffened up the tool post as it had too much movement. Then I was extra fussy about being square in for the cut. Then I tried locking the way slide too eliminate any movement there. Tried different parting blades and grinding profiles.  Setting the cutting height was addressed too. Saturating constantly with cutting oil helped a lot as did maintaining feed and rate. Didn't matter whether it was steel or aluminum. Anything over an inch I just used a hacksaw. I have seen the holders made for mounting on the cross slide so the parting tool has better support and the chips can fall out of the cut easier. I was going to try making one of those and trying it. The next easiest I would think would be to buy a lathe with more control and sturdiness. Thanks for the posts here and the links which I use.


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## GoceKU (Aug 18, 2017)

When i first started i also had troubles with parting, broke the HSS parting blade 6-7 times until there was nothing left, but found out you need confidence, once you start feeding the cat you don't stop unless the sound changes you'll learn the sound when the tool starts to bind up i usually try once more sometimes continues sometime i need to make an relief cut and i never go to the bottom i leave 3-4 mm which i break by hand and you must be sure your work piece is very tight in the chuck, even the slightest movement will break you tool, hope this helps Doodle.


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## kf4zht (Aug 29, 2017)

DAT510 said:


> Shars carries T type parting blades starting at around $11, for M42, depending on width.  Cheaper for HSS
> 
> http://www.shars.com/media/flip/master/mobile/index.html#p=67



I've used these on aluminum with an chinese AXA parting holder. As long as you get the tool centered and clean the chips with either a brush or coolant it cuts like butter.


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