Best way to shorten a power hacksaw blade

[Peter S]

I think I read on this forum that someone used a small ball end carbide burr in a die grinder. Or maybe a conical carbide burr.

I tried a 1/8" shank ball end carbide burr in a pencil-type air grinder and it didn't work at all. It did chip the burr though

 

[Limy Sami]

Back in the day we used to do the holes with a carbon arc rod.

 

[rimcanyon]

Carbide end mill did the job, thanks for the suggestions. However, even with a carbide end mill, i had stacked five blades to machine in one go (with teeth alternating side to side so that the stack remained flat), and the bottom blade fractured just like the blade I tried drilling with a carbide drill. I think back support is just as important as using the right tool for a job like this. I had set the blades up with a 9/16" gap around the hole location, well clamped on both sides. Probably should have used a piece of scrap aluminum under the blade stack.

 

[eKretz]

Carbide end mill did the job, thanks for the suggestions. However, even with a carbide end mill, i had stacked five blades to machine in one go (with teeth alternating side to side so that the stack remained flat), and the bottom blade fractured just like the blade I tried drilling with a carbide drill. I think back support is just as important as using the right tool for a job like this. I had set the blades up with a 9/16" gap around the hole location, well clamped on both sides. Probably should have used a piece of scrap aluminum under the blade stack.

Yes, especially with that amount of cutting. Carbide is hard, but it still gets dulled pretty quickly by cutting HSS.

 

[Milland]

I'll be curious about how the drilled blades hold up under load. I'd guess the sharp edge of the hole could be a stress riser that might lead to fracture during cutting or even tensioning.

Wear your safety glasses...

 

[eKretz]

Could always round the edges with a burr, but I don't think it will present a problem as long as they aren't already cracked or anything.