[subnoize]

Hello! If somebody would like to comment on my plans here it would be nice. I'm hoping somebody will see an obvious flaw in my plans and point it out. I have actually tried to find classes in milling but the cost was crazy expensive (literally 3 times the cost of my milling machine) and was at a local community college.

I have had my X3 (full 3 axis conversion run by LinuxCNC) for a few years now. I was an idiot and tried to start with aluminium and of course broke a lot of end mills and eventually lost interest. I've been using a 3D printer since but I will always come back to the question of "what if this part was metal" so here I am back trying again!

A little older and hopefully a little wiser, right?

This time I am going with a mild cold rolled 1018 steel. I got a great deal on a 3.5" x 3.5" x 5" end of a bar. I have a HSS 3/4" (19.05mm) flat end mill with 4 flutes to use for this experiment.

Since my machine is set up in metric the rest is in metric;


The Android speeds and feeds calculator says I should cut this block using 562 RPM at 215.64 mm/min. Vc: 34 m/min fz: 0.0960 mm

I have also switched CAM software and now using Fusion360 from Rhino+MadCAM. I am finding all of the features I need for the moment and even did a couple of dry runs of files it produced. It seems like its spot on with no bad habits.

I was thinking about just milling part of the block flat to start with. Get a feel for what the machine sounds like, how it behaves while cutting.

I would like to start with the ugly end and cut it smooth going a max of 1 or 2 mm step down per pass and taking it slow. This is the natural end of the bar and is very uneven. My fear is this is the 3.5 x 3.5 sides being gripped and the 5" height making the stock stick way out of the vise so it may not be stable. I am worried about the cutting process acting like a lever and yanking it out of the vise? Will it be that strong of a force from cutting it?

Anyways, going slow cutting the bad end smooth should give me a feel for how loud it will be and how much the machine will vibrate and stuff. Things that scare noobies like myself.

What do you all think? Is this a reasonable plan?



Thanks!

[Jim Dawson]

That's a lot of endmill for that machine, but doable. Slow & easy. If your software has a feed speed override, you might start at a lower setting and increase it as you see how it cuts. You will be able to hear and feel when the cutter and machine are happy. 215mm/min seems a bit fast.

You might take a look here. Sieg Super X3 Mill

[subnoize]

That's a lot of endmill for that machine, but doable. Slow & easy. If your software has a feed speed override, you might start at a lower setting and increase it as you see how it cuts. You will be able to hear and feel when the cutter and machine are happy. 215mm/min seems a bit fast.

You might take a look here. Sieg Super X3 Mill

Interesting, I never read that page through until now. I always just glanced it over when it popped up in my search results. The end mill is kind of big and I am moving a little fast and going way too deep so I will adjust it.

This first cut can take all day. I just want to hear, see, feel and smell what this thing is going to do while not breaking end mills. I think I will go with the half inch HSS end mill. Give myself a better chance of succeeding.

Thanks for pointing this out!

[subnoize]

That's a lot of endmill for that machine, but doable. Slow & easy.

Well, I took off about 5 mm of the 1018 bar where it was rough without a hitch. The end mill survived (the 1/2" HSS) which is always nice. The calculator seem to be pretty accurate as to the speed and feeds. I have a Kodiak Cutting Tools Solid Carbide End Mill, AlTiN Coated, 4 Flute, 1/2" Diameter, 1/2" Shank, 1-1/4" Length of Cut, 3" Overall Length arriving tomorrow. It will make cutting a little quicker I guess.

Quick question about cooling on such a small mill!

Since I don't have a coolant system on this mill, should I buy a bottle of the coolant and a mister bottle and spry it directly?


--jb

[Jim Dawson]

A spray bottle will work. My prefered coolant device is a fogless mister, like a FogBuster. Coolant Sprayers: FogBuster is a non fogging coolant sprayer mist systems, machining sprayers, spray lubrication system, metal rolling and forming lubrication system, oil mist cooling, metal coolant nozzles, spray lubricating systems, cnc machine cool

I just built my own, pretty easy to make. Uses about 1 quart of coolant in 8 hours of spindle time. The goal is to spray micro-droplets rather than a fine mist that creates a fog.

[subnoize]

Thank you very much, Mr. Dawson! I appreciate the help. You made my weekend go better than expected. I will check into the FogBuster.

[Jim Dawson]

It's my pleasure to help out