@GunsOfNavarone Thanks, those are pretty cool, hadn't seen them before. I already have the stepper motors and controllers, so it doesn't make sense to buy more (unless the current ones don't work), and those are pretty pricey.
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LMS 3960 X-axis Power Feed (the powerglide experiment)
- Thread starter Tio Loco
- Start date
- Joined
- Jul 9, 2019
- Messages
- 70
Thanks man! I bought a commercial 15 cue ignition system but I'm not happy with it. If you want it done right you gotta do it yourself
New one should be awesome! Can't wait to work with Arduino, all my parts should arrive by mid nextweek at the latest.
If there's no pyro there's no party!
-Jamie M.
Time, OK, past time for a progress update. Get some popcorn, this will be another long post.
New V2 end cap for the mill table. The lip facilitates and supports the modular power feed assembly which can be easily removed (3 screws) for service or adjustment.
One issue with the V1 was the short aluminum adapter from the lead screw to the bevel gear allowed excessive gear wobble. For V2 I designed a deeper bearing housing allowing for a longer adapter. The sealed bearing is retained with an internal c-clip (another new adventure). The slot in the bottom allows access to the set screw on the adapter.
V2 adapter is 1144 instead of aluminum.
Transmission (NEMA 17) stepper motor to engage/disengage the drive (NEMA 23) motor.
Transmission nut mount
Linear bearing carrier.
Transmission test fit.
I wasn't happy with the standard linear bearing mounts commonly used on 3D printers. Too blulky, bearings were rough and noisy, and 16 mounting screws made a smoothly sliding alignment a PITA, so I printed more svelte ones. The bearings are a perfect press fit, so no c-clips needed, making for a shorter mount.
Full V2 assembly
And the electronics. Clockwise from top right: 2-line LCD display for status of the motors (and eventually feed rate display), drive motor driver, transmission motor driver with limit switches attached, slide pot for speed direction control, Arduino Uno micro controller. In the far back at 12 o'clock position is the Arduino Nano, which will be used instead of the Uno for the final installation.
I have the preliminary sketch (program) written and functional, still needs a bit of tuning. There will just be two controls, an on/off switch will power the motor drivers, which will power the Arduino, and the slider for direction and speed. Center of the slider is neutral. Moving it in either direction will activate the transmission motor to engage the gears, then spin up the drive motor. Vice versa for moving the slider to neutral.
But.... There are several things I'm not happy with. As my better half told me, "That's why they call it prototyping".
The cog belt arrangement works, but it's needlessly complex, and I'm not overly confident about long term reliability. I was also struggling with the location for the transmission limit switches. My preference would be to keep them, and the requisite wiring out of the mechanical area if possible.
So, on to V3. Minor changes the design of the left plate, linear bearing carrier, drive motor mount and transmission motor mount will allow a change to direct drive of the transmission assembly.
Haven't completed modeling the electronics box, but each circuit will be on a slide-in tray.
The link from the drive motor mount and passing thru the transmission motor mount is a brass rod, threaded on each end, and will replace one of the drive motor mounting screws. This will allow the limit switches to be housed inside the electronics box out of harms way.
That sums things up as they stand today, but the end is in sight. Still noodling how to mount a magnet to the lead screw spur gear, so I can read the RPM's, and from there I can calculate the feed rate.
Now back to the mill to create fresh aluminum swarf... stay tuned.
New V2 end cap for the mill table. The lip facilitates and supports the modular power feed assembly which can be easily removed (3 screws) for service or adjustment.
One issue with the V1 was the short aluminum adapter from the lead screw to the bevel gear allowed excessive gear wobble. For V2 I designed a deeper bearing housing allowing for a longer adapter. The sealed bearing is retained with an internal c-clip (another new adventure). The slot in the bottom allows access to the set screw on the adapter.
V2 adapter is 1144 instead of aluminum.
Transmission (NEMA 17) stepper motor to engage/disengage the drive (NEMA 23) motor.
Transmission nut mount
Linear bearing carrier.
Transmission test fit.
I wasn't happy with the standard linear bearing mounts commonly used on 3D printers. Too blulky, bearings were rough and noisy, and 16 mounting screws made a smoothly sliding alignment a PITA, so I printed more svelte ones. The bearings are a perfect press fit, so no c-clips needed, making for a shorter mount.
Full V2 assembly
And the electronics. Clockwise from top right: 2-line LCD display for status of the motors (and eventually feed rate display), drive motor driver, transmission motor driver with limit switches attached, slide pot for speed direction control, Arduino Uno micro controller. In the far back at 12 o'clock position is the Arduino Nano, which will be used instead of the Uno for the final installation.
I have the preliminary sketch (program) written and functional, still needs a bit of tuning. There will just be two controls, an on/off switch will power the motor drivers, which will power the Arduino, and the slider for direction and speed. Center of the slider is neutral. Moving it in either direction will activate the transmission motor to engage the gears, then spin up the drive motor. Vice versa for moving the slider to neutral.
But.... There are several things I'm not happy with. As my better half told me, "That's why they call it prototyping".
The cog belt arrangement works, but it's needlessly complex, and I'm not overly confident about long term reliability. I was also struggling with the location for the transmission limit switches. My preference would be to keep them, and the requisite wiring out of the mechanical area if possible.
So, on to V3. Minor changes the design of the left plate, linear bearing carrier, drive motor mount and transmission motor mount will allow a change to direct drive of the transmission assembly.
Haven't completed modeling the electronics box, but each circuit will be on a slide-in tray.
The link from the drive motor mount and passing thru the transmission motor mount is a brass rod, threaded on each end, and will replace one of the drive motor mounting screws. This will allow the limit switches to be housed inside the electronics box out of harms way.
That sums things up as they stand today, but the end is in sight. Still noodling how to mount a magnet to the lead screw spur gear, so I can read the RPM's, and from there I can calculate the feed rate.
Now back to the mill to create fresh aluminum swarf... stay tuned.
- Joined
- Jul 9, 2019
- Messages
- 70
Absolutely amazing, can't wait to see it run in anger
Thanks for sharing all the sketches and photos!
For the RPM on my lathe I epoxied a N52 magnet to the chuck shaft then used one of those hall detection RPM sensors and it works flawless, right up to my maximum 2400rpm!
-Jamie M.
Thanks for sharing all the sketches and photos!
For the RPM on my lathe I epoxied a N52 magnet to the chuck shaft then used one of those hall detection RPM sensors and it works flawless, right up to my maximum 2400rpm!
-Jamie M.
@toysareforboys Thanks! That's my plan. I'm thinking a collar for the lead screw bevel gear that will put the magnet to put the magnet out close to the electronics box, and mount a hall effect sensor in the electronics box, again I don't want any more wiring out in the mechanical zone than absolutely necessary.