# The last cutoff/parting tool I'll ever buy?



## juiceclone (Feb 15, 2015)

This may be the last parting/cutoff tool I will ever have to buy.
Not elegant or complicated but it works.
I got a 4 in “plate joiner saw blade” from Harbor Freight for $10 bucks and a ¾-16 x 4in bolt and nut from a hardware store for another sawbuck. The .750 bolt fits my AXA QC tool post boring bar holder correctly, and I cut an .875 x .093 shoulder in the head of the bolt …. (needs to be slightly less than the thickness of whatever blade you use) The HF blade has 6 carbide cutters aprox .140 thick so that’s the width of the cut. I ground two of the carbide tips to have a flat cut, and one of those I thinned to the thickness of the blade, approx .110. I drilled and tapped an index pin hole in my boring bar tool holder (the only change to that) and drilled 6 index holes in the blade so it can’t turn when cutting. I did find this necessary because I tried a prototype without and under heavy load it would shift down. Of course that could be a plus because it will stop cutting if you go in too fast :>)) I can see that in a deep cut I might have a problem with chip blockage, but I can always grind clearance deep on one spot for that. This thing is SOLID. All that metal above and below the actual cut point does not flex, particularly from side to side as I have seen in all other cutoff/parting tools . It seems to be flexing down the entire cross/compound on my Chinese lathe when I push it too much.. There are other blades available everywhere that could be thinner and ?better? suited to this. Most of them have many more teeth some of which would probably need to be ground off to be suitable. I got this idea from another? Forum somewhere where the guy ground part of a blade to fit his cutoff blade holder.


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## randyc (Feb 15, 2015)

What a clever idea !


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## JimDawson (Feb 16, 2015)

That is one of the most interesting ways of making a parting tool that I have ever seen.  I'm going to have to build one.


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## bpratl (Feb 16, 2015)

Great Idea....next trip to HF I will pick up a cutter.


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## Billh50 (Feb 16, 2015)

$10 for 6 cut off blades in one is not a bad deal at all.


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## FOMOGO (Feb 16, 2015)

Nicely done. Will have to give that a try. Thanks for posting. Mike


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## Ken_Shea (Feb 16, 2015)

That may be the last cut off tool I ever need to buy as well 

I love it.


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## gjmontll (Feb 16, 2015)

Very nice, I too will put it on my to-do list. Question: If you drilled holes in the blade, then it must not be hardened, right?
   Greg


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## juiceclone (Feb 16, 2015)

gjmontll said:


> Very nice, I too will put it on my to-do list. Question: If you drilled holes in the blade, then it must not be hardened, right?
> Greg


it wasn't hardened, but fairly tough stuff ...three sharpenings of the drill to get six holes .... the outside surface seemed to be harder to drill ....once you were in it drilled pretty good till the other side..lots of coolant/lube


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## rbertalotto (Feb 16, 2015)

awesome!


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## petcnc (Feb 16, 2015)

Very clever!
I like the six-pack idea of the tool.
It reminds me of something... but I can not recall right now..


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## basildoug10 (Feb 16, 2015)

I think your idea of a parting tool is excellent. I have myself, tried various types of parting tool arrangements and I have had some serious breakages. I now wear a full face shield and make sure that I clear the place around me to make a quick "getaway" in the event of a jam.
I will definitely look for a joiner blade and make a parting tool like yours.

A good idea that is well executed
Regards Basil


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## kd4gij (Feb 16, 2015)

Thanks forpsting this. I just may have to try it.


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## thomas s (Feb 16, 2015)

I like it great idea thanks for posting.


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## Lornie McCullough (Feb 17, 2015)

Great idea and good explanation. I just happen to be going to HF tomorrow, and added one blade to my shopping list. Thank you.

Lornie


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## Cadillac STS (Feb 17, 2015)

Great idea.  I liked the idea someone had of cutting parting tools out of saw blades then putting them in a parting tool holder.  This is better than that!


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## chips&more (Feb 17, 2015)

Now that's yankee ingenuity!


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## RJSakowski (Feb 17, 2015)

juiceclone said:


> This may be the last parting/cutoff tool I will ever have to buy.
> Not elegant or complicated but it works.
> I got a 4 in “plate joiner saw blade” from Harbor Freight for $10 bucks and a ¾-16 x 4in bolt and nut from a hardware store for another sawbuck. The .750 bolt fits my AXA QC tool post boring bar holder correctly, and I cut an .875 x .093 shoulder in the head of the bolt …. (needs to be slightly less than the thickness of whatever blade you use) The HF blade has 6 carbide cutters aprox .140 thick so that’s the width of the cut. I ground two of the carbide tips to have a flat cut, and one of those I thinned to the thickness of the blade, approx .110. I drilled and tapped an index pin hole in my boring bar tool holder (the only change to that) and drilled 6 index holes in the blade so it can’t turn when cutting. I did find this necessary because I tried a prototype without and under heavy load it would shift down. Of course that could be a plus because it will stop cutting if you go in too fast :>)) I can see that in a deep cut I might have a problem with chip blockage, but I can always grind clearance deep on one spot for that. This thing is SOLID. All that metal above and below the actual cut point does not flex, particularly from side to side as I have seen in all other cutoff/parting tools . It seems to be flexing down the entire cross/compound on my Chinese lathe when I push it too much.. There are other blades available everywhere that could be thinner and ?better? suited to this. Most of them have many more teeth some of which would probably need to be ground off to be suitable. I got this idea from another? Forum somewhere where the guy ground part of a blade to fit his cutoff blade holder.
> 
> ...


Clever!  It looks like you are using the boring bar holder for the QCTP.  What do your index holes mate to?   Did you drill a corresponding hole in the boring bar holder?


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## eightball (Feb 17, 2015)

Great idea!  I have had good results parting by running the lathe in reverse and turning the tool upside down. It seems to push off instead of digging in if you get too aggresive. I dont think ive ever broke an insert parting in reverse. I have broke tons of in forward lol. With your setup here,  that would be easy to do, and you could still get next to a shoulder if needed.


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## Dave Smith (Feb 17, 2015)

Gunrunner you need to order a set of these for the Z axis hand crank. Bill did you just spit coffee on your monitor? :rofl:

View attachment 253356


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## juiceclone (Feb 17, 2015)

RJSakowski said:


> Clever!  It looks like you are using the boring bar holder for the QCTP.  What do your index holes mate to?   Did you drill a corresponding hole in the boring bar holder?


 yes .. 1/4 x 20 "pin" in a meaty part of the holder...click on the last  pix (thumbnail) , for some reason it didn't show full size


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## Dave Smith (Feb 18, 2015)

Gunrunner you need to order a set of these for the Z axis hand crank. Bill did you just spit coffee on your monitor? :rofl:

View attachment 253356


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## Andre (Feb 18, 2015)

That's a cool idea, now you just need to make it spin!


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## juiceclone (Feb 18, 2015)

I'm hoping to hear how this works for others with "real" lathes.  My Sumore sp2304 is not a very good test!!


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