Trying again... Help with Depth and Feedrates by Wood Species

[richahrens]

Hi, everyone!

My name is Rich and I live in rural Vermont. I've been building for 40 years and have had my hands in woodworking for nearly as long being as I define the two as different, yet related. As I get older I have somehow gotten a little bit wiser and realize that I'd rather be doing shop work than hauling 2x10s up two stories to set rafters. Materials have gotten heavier and I want to preserve my strength and agility and not risk injury. That being said...

I purchased a ShopBot Buddy PRS Alpha 48 with 2.2 HP spindle and 12" z axis. My ambition is to make signs, architectural elements for other builders, do reproduction work with a digitizer and also make some home items like cutting boards and decorative items with inlays. I'm a real newbie to the CNC but have pretty decent computer and design skills. I apologize up front that I'll likely be asking some frequent, dumb questions.

So my first inquiry to the forum is this:

Has anyone compiled data and created any kind of chart or info graphic that generally "suggests" technical information by wood species for different bits with feed rates, spindle speed and pass depths?

At least for me at an early stage with lack of experience, it would be very helpful to avoid ruining my parts, prematurely wearing on expensive Amanda bits and generally frustrating myself as I work to gain new skills. I may well be wrong, but would think that regardless of the machine and router or spindle that there are best practices in this regard.

I thank you for your time and patience with me!

[steve_g]

Rich…

If you cut the same parts every day from the same materials, like a cabinet shop, strict adherence to manufacturers chiploads will give you the best bit life… in the real world where most of us live, many types of materials are seen! There are “guidelines” most of us live by… unfortunately, most of these “rules of thumb” come with experience! First of all, your bit should remain cool enough to touch after completing a cut… The chips should carry the heat away with them! Second, you should be making chips or shavings, not dust! One rule of thumb you’ll hear here, “like a baby, a screaming bit is a hungry bit!” To give a screaming bit a higher chipload, you must either increase the travel speed (IPS) or decrease the router/spindle speed (RPM). One common occurrence newbies get concerned with is a “chirp” or momentary “scream” while a bit ramps into and out of a corner… that’s OK.

If I was teaching a class of high schoolers, I’d be more apt to give specific chiploads for the Pine and plywood they’d be cutting, but since you’re an experienced woodworker, you know how a router cutting wood should sound! Also, Cherry from Texas cuts different than cherry from Michigan. Buy a little bit extra when trying a new materials and plan on breaking a few bits your first year!

Have fun! Ask questions, and post results!

SG

[bleeth]

Here's some "bits" about bits generously compiled and shared by other botters.

[richahrens]

Thanks! I'll print a copy to post by my Bot.