Carbide 3D End Mills - Chipload?

(Pascal) #1

Hello guys

I’m miss some information about the Carbide 3D End Mills. Is there a list with the detailed informations aboud the End Mills sold by Carbide 3D?
I need the missing informations to calculate the max feed speeds for different materials not covert by the auto toolpath feature.

Best regards
Pascal

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(Danny Harper) #2

What kind of info do you need?

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(Pascal) #3

Something like this: http://harveytool.com/secure/Content/Documents/SF_13900.pdf

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#4

I think OLA(overall length) would be good to have as well. I think there should be enough info listed that a person could create the tool in Fusion 360 without purchasing it.

@Apotessar I’ve been using 100in/min .08" step down .08" stepover on MDF with the 1/4" flat and ball from Carbid3d on the SO3. When a job is done the bit can be touched by hand, so it would appear to be a decent starting point.

Hardwoods 70-90 same stepovers.

I used a trial from gwizzard to get those numbers. If I ever get all the tools from carbide3d I’ll upload a tool library for Fusion 360 pre-populated with the numbers for different materials I’ve tried.

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(Danny Harper) #5

Cutting Alu.

The best way to do it for these machines(for me,indignant machinists need not apply) is simple,get a sample material and run a squared off spiral with a shallow DoP (.15mm is a good start) while ramping feed speed,watch the cutter closely,you are looking for ‘bow wave’ of material,once you see this,ramp the speed of the spindle up and see if it vanishes. You want to hover just before the point of that occurring. Note the RPM and feed speed. Add those parameters to you chip calc and see what Feed per tooth you have,apply that to you future dealings with that particular tool/material. You can increase DoP as your project dictates as long as feed per tooth remains in the same area. Cutter diameter plays a huge role in what you can cut effectively,I run 3mm 2 flutes,I know others run 4 Flutes in 6mm and cut faster but the tradeoff is mess and noise. Cutting faster does degrade surface finish however.

Very unscientific but works very well.

I find the chip load tables to be less useful for these less rigid machines.

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(Pascal) #6

Funny, I find them real useful for small machines. The Nomad 883 is my first step in milling, so I got a very limited feeling for seeds and speeds. Most of my start values are written down from posts iv’e red so far.
For me some fixed values are good to evaluate more values. Like having a good feed rate is perfect to start rising the plunge value. It is OK to guess both, but the result seems to be random.

For example lets take some Harveytool values: 0.125 inch Diameter, 10000 RPM (Nomad CNC Max), 2 Flutes and 0.00198 Chipload Value for Roughing (0.125100002*0.00198 = Feedrate 4.95 Inch/Min). The result is very close to the values I have found online for 6061.

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(Mark Bellon) #7

The Nomad is quite a stable, rigid machine - 0.001" repeatability. Small doesn’t mean lack of quality.

I can’t speak to the SO3 but I would suspect it doesn’t do as well as that Nomad for repeatability.

I find the chip load tables to be less useful for these less rigid machines.

I find the chip load tables amazingly useful. I use them to double check what G-Wizard is telling me.

Can’t agree more about needing to experiment, regardless of tables. I teach chevrons, rather than spirals. YMMV.

Metals and plastics, as long as one knows the formulation/alloy, perform very close to their tabled data. I rarely find the need to experiment; the tables and G-Wizard are “spot on”.

Wood on the other hand, absolutely requires experimentation. For example, Oak. Quercus Alba (American)? Quercus Robur (European)? Which area? Oak can vary in density and hardness by quite a bit. Pine? Is it Yellow Pine? Yellow Pine is a hardwood, not a software or medium wood.

End mill diameter is a major factor in machining. It affects speed and finish. Flutes? There are many to choose from, each with interesting results. More flutes doesn’t always mean faster… and finish may not be as good. Noise? Yup! A proper enclosure and this isn’t as much as an issue.

Good feeds and speeds is not just about the simple calculation. There has to be sufficient torque to keep it going. One also have to add the deflection adjustment for the “stick out”. When all is done properly, the results are as good as it can get.

mark

P.S.

Using others feeds and speeds is likely to lead to disasters. Unless from a trusted source, one could have poor numbers, really mistaken numbers, or numbers that do not work for you (stock variation).
Be careful!

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(Danny Harper) #8

Interesting,I have to revisit them for this machine. The So3 does have repeatability,I often run multistage jobs with changes with no loss of accuracy,what It does have is flex,and quite a lot of it,in the Z. You will need to adapt your code to allow for it,normally by careful feed balancing.

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