Need help understanding spindle specs

[Chelmite]

I'm sorry. I didn't intend to offend. I've been trying to get an answer to my question for 3 days, so I tried refining the question. I tried to point out what info I was needing and made constructive suggestions about what was lacking. Asking clarifying questions is not attitude. It shows that I care about the answer and respect the person enough ask him for information.

Then it turned into a discussion. Discussions are great. We all contribute something and all get something out of it. I documented my info source on HP & speeds to help others and show that I'm not just making this stuff up.

At no time did I put down anyone, other than make a joke at my own expense. Sometimes the humor is lost in the land of text. I didn't mean it to be offensive.

[adrianm]

What type of wood are you cutting? What pass depths? What type of tool?

240ipm seems very high for a desktop to me. As far as I know that's as fast as a desktop can move so you're right on the limit. I wouldn't push my PRS Alpha with a 2.2hp spindle that fast in a lot of materials.

The CNCCookBook articles are aimed more at machining metal than they are at wood users. Nearly all of the variables they mention just confuse the issue.

With wood just start slow and start upping the speed until the finish deteriorates or some part of the machine starts to struggle. You're then in the ballpark and you can fine tune from there.

Bear in mind that atmospheric conditions, different batches of the same type of wood and the newness of the cutting tool used will all effect the speeds you need to use.

That's where using your ears comes into as Brady said. As those variables I mentioned change you'll hear the cutter struggling or even under working and you'll be able to adjust for the situation.

It's not an exact science where you can type in a bunch of figures and it will tell you exactly what you need to do. It's a learning process between you, the type of work you want to do and what your machine is capable of.

[scottp55]

Steve, I very much agree with Adrian on you maybe pushing the envelope to much. We are doing prototypes that are being passed around New England so quality is most important and finishing is very time consuming compared to cutting. I can run faster than I do, but I'll have to run the piece twice because of the finish and bit deflection and I'd rather run it once slow than twice fast. Always check your bit temp after a new wood or cut(should be room temp). Mainly cutting sugar maple ,but out of our 20 bits very few like faster than 1.7 IPS and most do best in the 1.1-1.5 IPS range(most of our bits smaller than .2") and none like faster than 16K. Fastest is 3 IPS for surfacing routine at 12K. Run the same routine again and you can hear how much bit deflection you are getting. Again watch your depth of cut.
When running a new wood or new bit that is significantly different than anything you've done before and you're worried, I've found the people here on the forum very helpful(do a search first, as I've found most of my questions have already been covered-A google search is sometimes more helpful finding stuff than a forum search). At some point you WILL need the people here. I've seen 2 guys stall my Unisaw(hop hornbeam slab), that doesn't make it a bad machine. I do recommend you lose the gwizard for a couple months. I hope any of this was helpful, I ramble, Brady is succinct and VERY pertinent, Different styles. scott