CNC mill

[Stytooner]

I thought some of you might be interested in this. I uploaded a video of my newest helper in the shop. I have to rebuild it, but it will be making some of its own parts for the rebuild.

If you like watching paint dry, you will love this mill in action.

http://www.youtube.com/watch?v=YG7j_u5Ffgs

[Black wallnut]

Kewl, looks like your new hobby is paying off!

[ironhat]

What does this require in the way of software? Is is pricey? Don't you have to add servos to the mill? Pricey? Isn't it obvious that I haven't a clue about CNC production?!!

[Stytooner]

These are actually just stepper motors. These are mid sized for steppers of this size. Nema 23. I have ordered the strongest I can get in this frame size. About twice as strong as these.

You can get all the software for free. The stuff I am using cost about $150 on average for Cam and Machine control. Turbocad and Corel Draw are the two other programs I use.
CNC can be done rather cheap. Less than $500 sans computer if you are thrifty. When done, this machine will be approaching $4000 including software, computer etc. Really not bad for a pretty accurate mill. I still have a lot of work to do to it. A steel frame bench I have will really give it something to sit on. It's not even bolted down in the video and it's on an old wooden plant stand.
I wanted to add a better detail pic of the finished milled product and perhaps the powder coated version as well. This was my first attemp at video editing, so there will be more to follow.
Thanks, guys.

[Black wallnut]

How about a pic posted here in the mean time?

[Tom Slick]

That is cool. It would be fun to make a CNC mill. I have experience operating and repairing, mostly repairing (actually certified), FADAL 4020 VMCs, it's neat to see a "little" mill. What machine is the base of your project?

Why does the Z go up so high for rapid moves? we'd only have 1/8-1/4" clearance for rapids. at a max of only 60 ipm any little bit would help shave off time.

[Uncle Cracker]

If you like watching paint dry, you will love this mill in action.

Judging by your background tunes, Lee, you already know this is how fast things are supposed to get done on I'island, mon...

[Stytooner]

The Z height is just my standard Safe Z. It's not a 60 IPM limit, that is just what this is set to now. It can rapid 150 easy with these small motors. Should do real well with the bigger motors. The machine isn't bolted down to anything right now. Just sitting there. You go too fast and it would be in your lap pretty quick.
Here is a link to the machines build log at the Zone.
http://www.cnczone.com/forums/showthread.php?t=32609

The music was just some samples that just happened to be the right length for this. I like the instrumental part. For some reason, my camera isn't recording sound. It did before, so time to check out the dreaded Owner's Manual.

Here is a close up of a clamp after powder coating. I went too deep on this one. Didn't know how much the coating would fill in. The newer ones are much shallower and a lot easier to see the detail. More pics when I can. Off to the Dentist.

[cgallery]

What are you doing for coolant? Pump/collection/filtering, etc. Is the pump under computer control, or do you switch it on/off separately?

Nice job, BTW.

[ironhat]

Dentist... aaaaaaaaaaaaaargh!!!!!!!!!!!!!!!!!!

[Stytooner]

What are you doing for coolant? Pump/collection/filtering, etc. Is the pump under computer control, or do you switch it on/off separately?

Nice job, BTW.

Right now I just use manual control on the spindle and the coolant. I will eventually get some relays and let the software control them as well.
The coolant tank is just a HF solvent tank. $49. 3.5 gallon I think. I just used some clear tubing and ran it up to the adjustable nozzle that came with it. I used a cheapo air valve there to regulate the flow. That was about half pressure on the video. I don't yet have walls on the enclosure, so no blasting away yet.
The coolant is Koolmist 77. Mixes with water at 4 oz per gallon of H2O. Nice stuff so far.
Thanks Guys.

[Tom Slick]

I checked out your writeups over at CNCzone. really cool! I had figured that you bought a small non-cnc knee mill and converted it. I didn't know it was made from scratch with 80/20. I don't know if I missed it but what are you using for a spindle? is the speed manual or set by your controller?
I've had problems with gas spring longevity for spindle counterbalance in commerical CNC applications, it might be fine for your machine though. the VMCs I've worked on had counterweights for the head.

[Stytooner]

You can buy just the spindle and head casting from a Seig X2 @ Little Machine Shop. Typical Chinese mid size mini mill like sold a Grizzly and HF.
The new spindle motor is a 2.5HP treadmill motor. I used a two speed belt drive conversion kit also sold at Little Machine Shop. Right now the speed is manually adjusted. I may install some sort of encoder on this motor so the software knows the spindle speed or I am also researching just putting a large servo motor on it with an encoder. Not sure which route I'll take or if it would just be more prudent to install an optical rpm sensor. I think this might be the cheapest and I could still use the big motor I already have. The drawback is the software couldn't read it very accurately. Not as accurate as a servo. A big servo could run into some bucks for it and a controller for it.

It was a lot of fun to build, mostly in spare time. I don't really have a lot of that though. It will receive another pretty major upgrade, and then I'll have some worth it's weight.

I have another of these springs. I bought a set. I just happened to buy these for another project that got canceled when I worked at the Beach. It was to be a lid for a bed mounted special toolbox in my pickup.
I have considered the steadfast weight and pulley system. There is also an air filled cylinder system that can be built as a counterweight. I imagine it would fail even quicker than the gas springs. This head probably weighs about 50 lbs. The struts are rated @ 30, so it is a pretty good balance as far as mechanicals go. No force needed for the Z motor to push down and it gets a little help to raise it up.
I had to have something. The ground ball screws are far to efficient to hold the Z up after power is turned off without the springs. So far, so good.

[footprintsinconc]

very cool! simply amazing! i'm just sitting here in amazement.

[Stytooner]

Check out this link.
http://www.instructables.com/tag/?q=...c=on&sort=none
I thought it was a very cool website.