Sharpening Bits

[Songweaver1]

Is there a good way to sharpen old cnc bits? I have several bull nose bits that have dulled over time (on the tips) but they still look good higher up on the bit shaft. I see bit sharpener tools and machines but I donb't see how they could do a very good job on bits like 1/16th or even 1/8th.

[ohiolyons]

Just google sharpening bits in your local area.

My local Woodcraft has a drop off service for sharpening services.

Doubtful if a local guy could do tapered spiral. but you never know until you ask.

[Phil]

Woodline advertises a bit sharpening service. Go to the bottom of this page.
https://www.woodline.com/?gclid=Cj0KCQj ... VMEALw_wcB

Phil

[adze_cnc]

I'm not sure about sharpening any kind of multi-flute spiral ball-nose bits (tapered or otherwise). There is so little material available as you get closer to the tip centre that it seems to me that the zero cutting spot at the centre of the tip would just get larger and larger.

Straight two-bladed cove-bits perhaps but is it worth the fee and shipping?

[Leo]

When I was working in the metal cutting industry we sent our carbide cutter for resharpening all the time.

The best is when they mount the cutter in a CNC cutter grinding.
They remake the cutter completely
What you get get in return is a brand new cutter - sometimes better than new.

BUT - there is always a BUT

A really good resharpening job will be a little smaller in diameter and you need to be able to accuratly measure and adjust for the size difference.

The resharpening cost may be as much as or higher than new - IF - you are trying to get EBAY cutters or bargain basement cutters resharped. If you bought premium cutters, the cost may be 1/2 to 2/3 the cost of a new cutter.

Sometimes it's just not justifyable - sharpening cost plus shipping cost.

It is not worth resharpening a 1/8" end mill
Resharpening a 1/2 carbide end mill may be worth the cost.

Then there is the task of finding a resharpening service that does a good job.

Personally - I just buy new cutters