My first low budget machine- tutorial

[Honus]

I've been a lurker for a while here and I finally got around to bulding my first low budget mill. I still need to mount the stepper motors and build a controller (right now it's manual.)

I posted a complete build tutorial here: http://www.instructables.com/id/Make...illing_machine

So far it's working well- I'm already working on modifications to make it better and I've been updating the tutorial as I go.

I'm staggered by the amount of knowledge available on this site and it's been a huge help. Hopefully I'll be building even better machines in the near future!

Jerome

[FandZ]

That's a really good write up. Your spindle really caught my eye. Actually my ears. It's so quite. At first I thought it was an audio problem until I heard you blowing the drilled bits out the way.

Can you give me some more information about your spindle? Like speeds, torque, and prices to build one. I would really like a similar setup on my build. I think that is plastic you are working on in the vid. Could it spin up fast enough to work with aluminum?

[Honus]

Thanks! That's actually wax I'm cutting in the video. The spindle is just a Foredom #44 handpiece with the end cap removed so I could attach a pulley to it. You can buy them directly from Foredom.com for around $60 or so but I think you can get one for a bit less if you shop around.

You can use any motor you like and gear it however you want.

[CarveOne]

Something like a large brushless motor and ESC from the electric R/C model hobby would allow the spindle to be run from a DC power supply and have speed control as well. Small engraving machines might make good use of this at craft shows where machine noise is an issue.

Gear reduction versions of the motors are available when more torque with less speed is needed.

CarveOne

[FandZ]

I have soo much to learn.

Originally Posted by Honus Thanks! That's actually wax I'm cutting in the video. The spindle is just a Foredom #44 handpiece with the end cap removed so I could attach a pulley to it. You can buy them directly from Foredom.com for around $60 or so but I think you can get one for a bit less if you shop around. You can use any motor you like and gear it however you want.

Originally Posted by CarveOne Something like a large brushless motor and ESC from the electric R/C model hobby would allow the spindle to be run from a DC power supply and have speed control as well. Small engraving machines might make good use of this at craft shows where machine noise is an issue. Gear reduction versions of the motors are available when more torque with less speed is needed. CarveOne

[Honus]

That's exactly what I plan on doing in the future. I'll use a microcontroller to send a PWM signal to the ESC. I have an older 30Amp ESC (forward only, no reverse or brake) that will work with my current motor since it's not brushless. If you can afford it, brushless is the way to go. I'll probably end up making my power supplies from desktop PC ATX power supplies.

Jerome

Originally Posted by CarveOne Something like a large brushless motor and ESC from the electric R/C model hobby would allow the spindle to be run from a DC power supply and have speed control as well. Small engraving machines might make good use of this at craft shows where machine noise is an issue. Gear reduction versions of the motors are available when more torque with less speed is needed. CarveOne

[CarveOne]

I have a Foredom Flexshaft tool with #44T (standard) and #28 (slimline) hand pieces. In another forum and thread on CNC Zone I suggested using one of the hand pieces for a making a CNC spindle. I was surprised to see how many versions are listed on the http://www.foredom.com/foundations/s...sp?category=59 website. Some of them are for continuous duty and / or high rpms.

I see no reason that one of their power heads and controllers couldn't be mounted together as a belt drive unit. The brushless R/C motor and ESC will be more compact though.

CarveOne

[Honus]

Generally speaking, the larger bodied handpieces (like the #44 and #30) are the most durable with the non duplex slimline handpieces second and the quick change handpieces third. I work as a professional jeweler and my #30 that I use at work everyday is over 11 years old and is still going strong. I usually destroy the quick change handpieces every 1 1/2 years and have to rebuild or replace them. It's usually the clutch/collet mechanism and the front bearing that goes.

All of the Foredom motors are really durable (I have three motors over 11 years old) but they're definitely louder than a separate DC motor/spindle setup. They do have a lot of torque though! They used to make a little 1/8hp motor (I have one at home) that is a nice size for a tiny mill. The speed controllers they make are nothing special in my experience.

Foredom also makes micromotor handpieces but they're pretty expensive- I believe. They would be good for making PCB's due to the high rpm's but they don't have a lot of torque. Ditto for the NSK micrmotor system- they do offer a gear reduction unit for it but the NSK setup is almost $1000.

Pfingst and Faro also make good handpieces.

[tahustvedt]

Originally Posted by Honus That's exactly what I plan on doing in the future. I'll use a microcontroller to send a PWM signal to the ESC. I have an older 30Amp ESC (forward only, no reverse or brake) that will work with my current motor since it's not brushless. If you can afford it, brushless is the way to go. I'll probably end up making my power supplies from desktop PC ATX power supplies. Jerome

Another thing that's cool about brushless ESCs is that they usually have a governor function which will hold the RPM constant under load. All Helicopter ESCs do.

[Honus]

Originally Posted by tahustvedt Another thing that's cool about brushless ESCs is that they usually have a governor function which will hold the RPM constant under load. All Helicopter ESCs do.

I didn't know that about heli ESCs- that's awesome.