[cyclotron]

Hi all,

I was wondering if folks could chime in on what speeds and feeds recipes they had some success with on the Dyna 2000/2100/2400? on Aluminum and steel? Info regarding any tool diameter would be helpful particularly feed per tooth and, width and depth of cut. I have mostly been machining HDPE and poly propylene on mine, but I'm getting ready to do some steel and aluminum, and I just want to get off the ground.

I've been roughing these plastics with a less then bullet proof setup at 1800 RPM, 0.25 diameter 4 flute, 20 IPM, .210 DOC, 0.1 WOC.

I'm not really sure what a good starting point is for aluminum and steel is however...

[acannell]

It sounds like you are a beginner, and making an earnest effort here, so I'll word my advice accordingly. I use a DM2900 and its a much bigger machine, but I'm guessing the 2000/2100/2400 are pretty capable even if they are smaller, if they are built as well as the DM2900.

-I'd start off with a 3/8, 2 flute, carbide endmill. Make sure its brand new and sharp. You may also want to get yourself a 2 or 3 flute, hss end mill to experiment with at the same time so you can compare.
-Minimize stickout as much as possible.
-Cut only 6061-T6. Do not attempt to cut other aluminum alloys. Some of them are very gummy and cut poorly, clogging flutes and melting (no, this is not anecdotal, its a real thing, well documented in professional literature)
-Keep a detailed log of your feed/speed experiments in excel. Note everything about the cut (axial doc, ipm, coolant, rpm, radial doc, etc..)
-Mount the stock as rigidly as possible, and practice cutting the thickest part of it to maximize rigidity.
-Start using a good feed/speed calculator to ballpark stuff. I use FSwizard (free, online). Set your cut up so you are using at most 1/3rd of the spindle horsepower.
-Shoot for a chip thickness of at least 1 thou. You can certainly cut 6061-T6 without coolant but coolant can improve things greatly, and may be required depending on the type of cut.
-Do whatever you need to to improve the rigidity of your machine (if that means tightening gibs, etc..)

Once you learn more you can abandon all the above but gotta start somewhere..

[cyclotron]

Acannell,

Thanks for the quick response, Your suggestions are all good ones, and totally appropriate for a beginner... I've been working in manual machine shops for about the last 4 years, so the basic concepts of rigidity, lubrication of cut, chip evacuation, tool stickout, solid setups, and trying to spec out parts in free(ish) machining materials, are not lost on me. I've been working with FSwizard but as a calculator it assumes the rest of your system outside of the cut is theoretically rigid (like a large machine tool designed properly for professional use). The trick here is that the 2400 machines are SO much lighter than something like a bridgeport (which is still on the light end IMHO), and are designed in a way that make them intrinsically less rigid, so it is hard to judge what would be reasonable speeds and feeds for a machine of it's size and weight. Since I know there are some other 2400 users here, I am hoping I can get some info about their empirical observations on what the machine is capable of in the more common metals. Of course I am also running my own experiments, but having some ball park figures would help set the extremes and guide that experimentation...

[Fastest1]

Anything larger than .25 end mill is just going to frustrate you on the 2400.
It is a wonderfully built little machine.

[cyclotron]

well, here is some of my recent work.

https://youtu.be/VINvrg2zuV8

1/8 hss endmill in aluminum (probably mic6) with compressed air and coolant. 10 ipm. about 0.1 DOC. unknown RPM. I modded my 2100 with a full cast iron headstock (original spindle) and 3/4 HP brushless servo motor.

The finish came out pretty nice, although if I look really closely, I can see "diagonal" chatter. Probably need to take a lighter finishing pass.

I'll try to post more vids and stats as I go. I'm going to get an RPM meter on order too.

[cyclotron]

oh yea FAstest1, Couldn't agree with you more! I love the tapered gibs!

[2ferrous]

Cutting speeds and feeds has more to do with the cutter than the machine itself.
The machine spindle motor size and rigidity of the column tells us how big of a cutter it can handle.
A typical 2 flute HSS 0.250 end mill should be spinning at 4800 rpm and feeding at 12 to 24 ipm.
Depth and width of cut is dependent on the machine, but you should be able to go 1D and 1W to use a cutter properly.
A carbide cutter can go much faster and quicker. In this example a 0.250 IMCO M202 can be spun at 12224 rpm and fed at 24.4 ipm.

Timothy