need infos for increase a hole from 3/4 to one inch this blade is from Stihl blade the number is T15 07 4000 713 3902 MAX 11500 RPM

[Marc Moreau]

This blade is designed to cut small tree branchches . Its thickness is 4 mm . I tried with my press drill at low rpm with all lubrican I had but I always damage my bit without success . I cannot mount it on my metal lathe. I need your experience. Thank You

 

[Martin w]

I have done carbide circular saw blade arbor holes on my mill. I use a boring head with a boring bar. Usually a couple passes to go from 1” to 30 mm. Run the mill fairly slow with a slow feed rate. Cuts very easily.. I usually clamp down and indicate the hole and then change to my boring head to bore the hole.
You would probably have a lot of chatter on a drill press using a drill.
Martin

 

[Mcgyver]

wonder what they make those out of? Must be tough stuff as the body is the same material as the cutting edge. what did you use for a drill, twist drill or step drill?

Even if it was mild steel, that would be hard to do on a drill press.

The way to do it is like Martin says, using a boring head in the mill. If its tough material light cuts with a carbide tool should work. I do this for my table saw - every blade starts at 5/8 but I need 20mm.

Do you have a mill? Cheapo boring heads aren't outrageous and work well enough. I thought about making a cutter like a counterbore with a pilot, but if its tough material that won't work well and it is an very big cut to do in one go. It needs boring in a bunch of little cuts me thinks.

Last ditched idea - file or if too tough, die grind. Incredibly accurate work, to a thou, can be done with filing but it takes lots of patience. Turn a test piece with a taper that you put blue on and keep measuring to keep it centered.

 

[Garyt]

I don't know how big this blade is, but I have had success screwing blades to a piece of mdf (or plywood) and holding in the four jaw. Adjusting the 4jaw until the existing hole runs on centre then just a boring job.
Gary