Very weird (to me at least) bit.

[bsilva]

I've had my Shopbot cutting for a few weeks and decided to go through to the bits that I havn't used yet and think about what I might do with each (mostly as a learning exercise).

I came across an Onsrud 42-005 (Single flute 5/16 HSS) that came with the Shopbot starter bit kit.

The thing is, this bit has an obviously tapered shaft (a caliper shows the butt of the bit being .405" and the shaft just above the flutes as being .351"). The cutting length is tapered as well, but why the heck is the _shaft_ tapered?

I thought this was a manufacturing defect, but it appears from the Onsrud catalog that this is the way they are made.

So, two three questions:
1) Why? Is it just manufacturing cost? (it's a $12.35 bit)
2) Is this even safe in an ER-25 collet?
3) If so, what size collet? 3/8" (.375")?

Any clues appreciated,
Thanks,
Brad

[c_kling]

Hello, Anyone experinced a problem via ArtCam 2008, receiving error " Wglcreatecontext failed" what is this? and how do i deal/correct this? thanks in advance.

[bsilva]

Christian, I think you meant to create a new thread (link on the bottom of the topic view).

Brad

[andyb]

Brad,
I think the bit you are refering to is the Super-O. The bit is safe to use, if you have the correct size collet. It uses a 13/32 collet. I've used the Super-O on plastic.

Andy B.

[bsilva]

I have other Super-O bits, but they do not have the tapered Shaft.

Anyway, I've found the problem. My Sample Bit box from Shopbot has a list of bits included in the box. The 42-005 is not on the list. However, a 48-005 is on the list. It looks like someone stuffed the wrong bit.

I'll call Shopbot for a replacement.

Regards,
Brad