Speeds and feeds for unclamped parts

[Mancipia Mariae]

Does the calculation for speeds and feeds depend on whether a part like a folder blade is clamped down or not? I'm using Lakeshore Carbide drills and reamers for pivot and stop pin holes and their chart says "starting parameters based on good work piece rigidity & machine rigidity..."

 

[HSC ///]

yes. Are you milling? how else would you mill metal without clamping it down?

 

[Mancipia Mariae]

yes. Are you milling? how else would you mill metal without clamping it down?

I used the wrong words, drilling and reaming with drill bits and reamers not end mills

 

[Stacy E. Apelt - Bladesmith]

Drilling with carbide bits on an unclamped piece of hard metal is just wasting expensive carbide bits as well as wasting any possible accuracy of the holes.
Any minute amount of chatter or movement will break the cutting edge of the bit. The piece should be firmly held down and prevented from movement in any plane.

 

[Crag the Brewer]

Carbide breaks easily.
Must hold securely.


With reaming, I like clamping in a vise, but that vise is floating on the drill press table, allowing it to just finding the holes, so any slight deviation the vise moves giving you a nice round accurate hole

 

[Hubert S.]

Carbide breaks easily.
Must hold securely.


With reaming, I like clamping in a vise, but that vise is floating on the drill press table, allowing it to just finding the holes, so any slight deviation the vise moves giving you a nice round accurate hole

I often do the same thing, even to let the drill find the center punch hole and move the vise so it's centered. Not sure if that would work well with a small carbide bit, my vise might be too hard to move and the drill might still snap. I really only use carbide bits on the milling machine, where everything is rigid. And on the lathe, with a drill chuck that I hold by hand and can let go of if I feel there is too much force. I made that floating chuck holder after breaking two carbide bits, expensive learning experience.

Why not drill before HT with a regular bit and just ream after with carbide?

 

[Mancipia Mariae]

Drilling with carbide bits on an unclamped piece of hard metal is just wasting expensive carbide bits as well as wasting any possible accuracy of the holes.
Any minute amount of chatter or movement will break the cutting edge of the bit. The piece should be firmly held down and prevented from movement in any plane.

I see, that's just what I observed in this tutorial:

I suppose a better way of going about it would be to make a template with the holes and have the blade/handle on top, then have the whole jig clamped to the milling table?