cutting mower blades

[Kitz]

Would anybody know what will cut thru a tempered mower blade. Ive got some real nice blades that the center hole is to smal. Ive went thru 2 bits so far. Thanks

 

[forgeblast]

Do you have a dremel that you can grind a hole, or a step-bit just go slow and cutting fluid.

 

[Kitz]

Do you have a dremel that you can grind a hole, or a step-bit just go slow and cutting fluid.

is 500 rpm slow enough thats as low as my drill press will go. i guess grinding a hole is the other option i used a couple bits and burn them up. im trying to get 7/8"
thx

 

[oldnslo]

Carbide would probably cut through but carbide is brittle and you must have the work piece clamped rigid. 7/8 carbide drill would probably cost more than the blades also.

 

[nazbom2]

I performed a similar job not to long ago, used a die grinder and just kept at it, wore the stone down pretty good but did what I wanted.

 

[forgeblast]

I think some of the guys in the welding forum were saying 250rpm for steel.

 

[rrrkkk]

Took it to a machine shop, put in mill and used a 7/8 carbide bit. Slow and lots of fluid, drilled 3 of them.

 

[fenix]

Makes me wonder the quality of the drill bits you are using.
There are a lot of Chinese drill bits being sold that are good for
wood or plastic only not for steel. I can't think a good quality bit would
not go right through a lawnmower blade. They are not that hard, if they
were, they would shatter on the first rock. Think how easy they are
to sharpen with a file.