Does climb or conventional milling only apply to edges of the work piece?

Chip load is often recommended by tool manufacturers and can be extrapolated to those tools that are not provided with cutting data.

Chip thickness is determined by tool geometry, coolant method, and material properties of the workpiece.

Here is the chart by Garr Tool which I often reference. These chiploads are usable for both carbide and HSS, but the Surface Speed (SFM) is specifically for carbide.

Use the columns on the right, selecting your tool diameter at the top. When choosing cutting parameters, I usually start at the lowest end of this spectrum and step up from there. But again, I have a small machine and those using large equipment can push these numbers harder.

Chip load is usually thought of as independent of other cutting parameters. Chip load and Surface Speed (SFM) determine spindle speed and feed rate for a given tool. Then WOC and DOC are chosen based on the type of cut needed and available horsepower.

Try punching these numbers into a speeds and feeds calculator (https://www.custompartnet.com/calculator/milling-speed-and-feed) and see how they get you the cutting data you need. Try bumping numbers up and down to get a feel for what affects what.

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Great question and one that I struggled with early on. Chip load is something that comes from the endmill's manufacturer. It's the amount of material each flute is capable of removing per revolution. A 1/2" carbide endmill's flute will remove a bigger chip than a 1/4" HSS endmill. The same endmill will remove more material in 1018 steel vs. Stainless. So the best place is to look at is the manufacturer's published data e.g.
They will often also tell you a way to calculate it for slotting.

However, for most of us hobbyists who are using 1/8-1/2" endmills in 1018 steel you want to make sure you don't go below .0005" per tooth as that will cause rubbing. I mostly use 1/4" and 3/8" HSS endmills and use .001" and .015" per tooth respectively. So you can write some of these down for your common end mills and tape them near the mill or make an index card and put in the calculator's pocket for quick reference.
 
I was always taught not to climb cut with a manual mill. You will be quickly reminded not to when the part you are milling is thrown across the room. Have not used a lot of carbide mostly high speed steel. With the work most of us do just get the speed of the mill close or even a little slower and you can tell the rest by feel and looking at the chips coming off. We aren't in production. If it takes a second longer to make a cut and saves on the end mill i am happy. Where i end up in trouble is trying to hurry and burn up or break an end mill. All the math is great for production but you can bury yourself in it real quick. You will have a feel for it after a while.usually if there are problems slower is the first thing to try.
 
I mean in general. I've already snapped 2 in the past. From what I've learned in this thread, I shouldn't slot DoC more than 50% of the endmill's diameter? 1/8 is .125, I think, so the maximum DoC slotting I should cut is .0625
 
Several factors to consider especially when slotting. Since the WOC is constant the only thing you have to tune your cut with is with your speed/feed and the DOC.

The DOC for slotting with a 1/8" solid carbide endmill should be anywhere from .25 times the diameter to .05 times the diameter. Go here http://niagaracutter.com/speedfeed scroll all the way down and see the footnotes on slotting and axial depth (DOC). Aluminum vs. steel vs. stainless etc will all require stepping up or stepping down on the feed/speeds. Start conservative.
 
Snapped my nice 1/4" 3 flute carbide endmill while side cutting hardened QCTP holder for my lathe. Had to use a 1/2" cobalt roughing endmill to finish the job

I'm gonna get a 3/8" cobalt roughing endmill and just use that for slotting and most everything else. I'll use regular end mill to do the finishing passes
 
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