Hello,

I'm having trouble machining a slit in a block of steel. I have used this tool and programmed it the exact same way with an aluminum part that is very similar with great success. Now I have a steel part and I am having a ton of problems with it.

Material is A36 steel
Blade is HSS with no coating
Depth of cut is .648" from edge of material
SFM is set to 110 for this material.

I have already broke one saw blade and have sheared the bolt that holds it in the arbor on another.


In the picture of the saw blade in the holder that is a 4" diameter 5/32" slitting saw. This is the perfect size slot to put in the part.
In the second picture you can see the 3" diameter slitting saw that broke. I have only ran about 50 aluminum parts just like this with success with this blade.
In the 3rd picture you can see where the blade was catching and stopping. Luckily I hit the e-stop before it broke my second blade.
In the 4th picture you can see where I did very small cuts to work my way in. This method is extremely time consuming and would not be cost effective.



Now in this group of images I am showing how I have this tool set up in onecnc and the pathing. This is the way I saw some people machining slots online. Is it better to come straight into the part or like this?
With these tool settings I was able to successfully machine aluminum parts (of course with the aluminum SFM which means faster spindle speed etc.) I tried slowing the feedrate down to 2 ipm and tried speeding the spindle speed to 300. Nothing seems to be working here.

I would greatly appreciate any insight you might have here. I have 5 of these that have to be finished tomorrow so I still have a little time to play with it but I'm down to my last slitting saw until I get more in.