# How to use thin slitting saws?



## carlquib (May 24, 2017)

I've used a lot of slotting and slitting saws over the years and they have always worked very well until I was trying to cut some deep narrow slits. I'm making some specialty collets and was using a 5" x 1/64" slitting saw cutting about 1 1/4" deep. I was going full depth with a cool mist running to clear chips and provide lubrication. All was going perfectly for the first couple cuts and then bang, no more slitting saw. I thought hmm maybe that is just too deep for a saw that narrow, so I switched to a 5" x 1/32" slitting saw. I finished the slit the other blade broke on with a jewellers saw by hand. I managed to finish slotting the next collet with the 1/32" saw but on the first cut of the third collet bang, gone. So my question is how do you make deep narrow slits. Obviously it can be done because I have collet sets with the narrow slits but obviously I don't know how to do it. The blades both broke when I was almost all the way through the bore with the slit, both times it was when I was almost finished. I was running at 60 rpm feeding slowly by hand. For my next attempt I got a left handed arbor so if the saw gets stuck hopefully the nut will nut come loose instead of grenading the blade. I haven't tried to finish yet with the new arbor. Any suggestions? The material is O1 drill rod and 1045 steel?

Sent from my SM-T550 using Tapatalk


----------



## EmilioG (May 24, 2017)

Have you checked the run out on your saw arbor, the arbor and blade? I think some will say you're running the blade too slowly. 60 rpm?


----------



## carlquib (May 24, 2017)

I have checked run out, about .0002" and the slitting saw was running out about .001" . For a slitting saw it sounded really good, hitting probably 80-90% of the teeth on the blade.  If I did the math right on a 5" diameter cutter that gives me about 80 sfm, which is about what I usually run hss at when I'm cutting high carbon or tool steel. 

Sent from my SM-T550 using Tapatalk


----------



## 4ssss (May 24, 2017)

The way I use slitting saws is to center the saw on the part and plunge it to depth, then clean up the bottom if needed.   I learned this from my 1st job, operating B&S screw machines.  The  slotting arm on them picks up the piece when it's cut off and plunges it into the saw.


----------



## chips&more (May 24, 2017)

Are you using blades from China?


----------



## brino (May 24, 2017)

There's a bunch of good info in the thread here:
http://www.hobby-machinist.com/threads/slitting-saw-woes.57779/'

-brino


----------



## carlquib (May 28, 2017)

I think my broken slitting saws are related to the interrupted nature of the cut, since I am cutting through the already cut bore of the collet. It appears I'm getting chips jammed as the blade tries to carry them through the second wall of the collet. I think I will try having the mister directed into the bore of the collet to try and clear the chips before they can jam the cut. 

Sent from my SM-G930P using Tapatalk


----------

