Power Z axis

Discussion on all milling machines vertical & horizontal, including but not limited to Bridgeports, Hardinge, South Bend, Clausing, Van Norman, including imports.

Moderators: GlennW, Harold_V

kl7sg
Posts: 75
Joined: Thu Oct 08, 2020 12:00 pm
Location: Springtown, TX

Re: Power Z axis

Post by kl7sg »

Sounds good.

My whole point is to show that the motor can be sized fairly accurately by making a few supported assumptions.
Have a nice day,

Mike
kl7sg
Posts: 75
Joined: Thu Oct 08, 2020 12:00 pm
Location: Springtown, TX

Re: Power Z axis

Post by kl7sg »

Sounds good.

My goal was to show motors can be sized fairly accurately using a few supported assumptions.
Have a nice day,

Mike
kl7sg
Posts: 75
Joined: Thu Oct 08, 2020 12:00 pm
Location: Springtown, TX

Re: Power Z axis

Post by kl7sg »

I have attached a paper on DC motors that might be helpful in visualizing DC motor efficiency.
Attachments
DC Motor.pdf
(423.46 KiB) Downloaded 267 times
Have a nice day,

Mike
User avatar
tornitore45
Posts: 2077
Joined: Tue Apr 18, 2006 12:24 am
Location: USA Texas, Austin

Re: Power Z axis

Post by tornitore45 »

The motor is a permanent magnets DC. The type you find in printers and cordless drill.
The motor takes 2.4A @12V just spinning in the breeze. I looked up a similar type on the Johnson Electric page is rated output is 175W but is only taking in 63W in this application so the efficiency is poor. It takes 5.6A under load. The voltage is nearly unchanged. So even neglecting the fact that resistance losses increase with the increased current Eff = (5.6-2.4)/5.6 = 57% Which is generous because the internal losses are higher under load than just the measured idle power drain.

All in all I am satisfied to have reconciliated and accounted for all the losses after guessing all the other moving part frictional losses.
Why I am doing this?
Because I am OCD, because I am retired and nothing better to do but I suspect because as part of my professional habit as a power supply designer I always did a loss reconciliation tallies for all designs.
Mauro Gaetano
in Austin TX
kl7sg
Posts: 75
Joined: Thu Oct 08, 2020 12:00 pm
Location: Springtown, TX

Re: Power Z axis

Post by kl7sg »

Hi Mauro,

Why do I do this? I haven't figured out why -- maybe just bored --
I am a retired aerospace engineer and I did systems and equipment design.
Now, I play around with machines and make trinkets for ham radio operators -- It keeps me off the streets :D
Have a nice day,

Mike
User avatar
tornitore45
Posts: 2077
Joined: Tue Apr 18, 2006 12:24 am
Location: USA Texas, Austin

Re: Power Z axis

Post by tornitore45 »

I am not bored, my mind creates more works that my body can flex to do. So is relaxing to go a bit deeper on tasks that are not physically taxing.
I have things in the yard to do fix paint but is darn hot. I just look around and say: I could put a shelf there and a new outlet and get the alarm clock off the night stand and visible. Plus I build model engines but for a change of scenery I am building a Tugboat now, then the mill Z axis motor blows up and need fixing and so it goes.
Mauro Gaetano
in Austin TX
kl7sg
Posts: 75
Joined: Thu Oct 08, 2020 12:00 pm
Location: Springtown, TX

Re: Power Z axis

Post by kl7sg »

Do you build model steam engines?
The reason I ask, is steam power has always interested me from childhood on...
The Union Pacific "Big Boy 4014" locomotive is passing through the DFW area on August 13th.
I hope to get to see it.
Have a nice day,

Mike
User avatar
tornitore45
Posts: 2077
Joined: Tue Apr 18, 2006 12:24 am
Location: USA Texas, Austin

Re: Power Z axis

Post by tornitore45 »

My first build was a marine type vertical double cylinder steam engine but then I found the IC more appealing.

Is almost worth a trip from Austin to see the Big Boy might give it a thought.
Mauro Gaetano
in Austin TX
kl7sg
Posts: 75
Joined: Thu Oct 08, 2020 12:00 pm
Location: Springtown, TX

Re: Power Z axis

Post by kl7sg »

It will be passing through Hearn, Navasota and Hempstead on Monday the 16th.
a lot closer to Austin.
Have a nice day,

Mike
User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: Power Z axis

Post by Harold_V »

If you enjoy live steam and have never seen a Big Boy, don't miss the opportunity. While I've not seen one under power, I have stood next to one that is on static display in Wyoming. Huge critter, it is.

I have a newspaper article, published in the early 60's, detailing the destruction of several of those magnificent engines by Geneva Steel (in Utah County, Utah), now defunct.

H
Wise people talk because they have something to say. Fools talk because they have to say something.
User avatar
tornitore45
Posts: 2077
Joined: Tue Apr 18, 2006 12:24 am
Location: USA Texas, Austin

Re: Power Z axis

Post by tornitore45 »

Big Boy will arrive in Hearn around 4:00PM and stop overnight
I am planning a trip from Austin on Sunday
Mauro Gaetano
in Austin TX
kl7sg
Posts: 75
Joined: Thu Oct 08, 2020 12:00 pm
Location: Springtown, TX

Re: Power Z axis

Post by kl7sg »

:D It will be fun to see one of those engines in operation :D
Have a nice day,

Mike
Post Reply