Spindle Chuck Questions

[SPEEDRE]

Here are some, maybe obvious, questions I have;
1. What's wrong with using, a regular 1/2" drill chuck instead of say a R8?
rpm range say 0 - 5000k rpm for light to medium milling?
2. What's wrong with using a router chuck extender, such as offered by
various mfg's. for wood and composite milling?
I believe that, most often as not, the most used cutter diameters are 1/8, 1/4, 3/8, 1/2, and so forth, and that these types can be used safety, and efficiently. These are low cost alternatives to spring types and R8's, and certainly offer themselves up for many installation methods. Am I barking into the wind, or is any of this valid?

[mxtras]

As far as the drill chuck - I chuck end mills in a drill chuck for counterboring only. Drill chucks and side loads don't like eachother. There are only three points of contact where a collet offers a lot more rigidity.

As far as the chuck extender - use when required but keep the length as short as needed. The farther away from support, the more chatter and deflection you will get and rigidity is of paramount importance when machining. Thisgs go wrong fast at 5K RPM.

Scott

[wcarrothers1]

You will break more end mills chucking them into a drill chuck due to the support issues Mxtras said.

Either way it's not something that you should do if collets are avaliable to hold them.

b./

[joe vidauri]

you never ever put an endmill in a drill chuck to side mill. you should onlt put an endmill in a drill chuck for counterboring. and even then be aware that your hole will most likely be oversize. a collet will hold a lot more true than a drill chuck for obvious reasons. i like to use shrink to fit holders you heat them up put the endmill in let them cool or use a chiller and they are as true as you can get right now. but just like always something else will surely come along.

[SPEEDRE]

So no drill chucks. OK. So a 1/4 dia. end mill is ok in a 1/4 collet and so forth. Got it, like I said obvious. Thanks for the reinforcement

[mxtras]

Collets are the way to go for smaller tooling. The drill chuck is required for holding the various diameters of drills, of course but for milling - a collet will hold the cutter securely, spin it accurately and offer the most rigidity.

Scott