El Beast - Initial design phase, comments and critique welcomed!

[Zeeflyboy]

The ones you made for me work well and are just tight enough but not too tight. You might have seen in the last video I put out that the steppers have no problem moving the axis so a big thank you for that.

Glad to hear it - haven't caught up on your work for a while actually... need to go see what's happened while i've been gone!

Missing a critical dimension is annoying. Sometimes I aim a few hundreds of a mm over size, check with the micrometer and use sand paper strips to get it to final size. Takes a while but quicker than starting again if you overshoot

Thanks - that's what I did this time and it worked well.

I assume you didn't fancy slots for the stepper to tension the belt? Also do you have bearings in the top plate for the end of the pulley and the end of the stepper shaft? If so I would make one of them floating in a separate small plate which bolts to the main plate. This will allow both bearings to sit where their respective shafts dictate - otherwise the pockets have to be machined very accurately. Something to think about. Have a good break and don't think about CNC too much.

Cheers for the thoughts. I was originally going to go with slots, but it makes it difficult to use a seperate bearing setup for the stepper motor which I wanted to do for the sake of my motor bearings, and the tensioner has the benefit of engaging more teeth on the small pulley.

I will think about floating the bearing above the ball screw - that's a good suggestion thanks.


So I re-made the shaft extension (it worked this time, I won't bore you with pictures as the process was much the same) and also made the knurled knob that allows me to manually move the Z-axis up/down. My thoughts are this is also an easy place to install a brake if the Z-axis proves heavy enough to slide down on it's own.

So started off by turning the alu stock down to size



Knurled and parting






Meanwhile, 3D printed a drill jig to make drilling the retaining grub screw hole easier.






Pressed into place




To save damaging the collar (plus it's a pretty small thing to clamp) I then mounted a 6mm rod in the lathe and used that to mount the knob to do the top side operations:




Final part:






This is the assembly:

[Nickhofen]

You are a bad guy!!! I have lathe envy now!

[routercnc]

You are a bad guy!!! I have lathe envy now!

I waited a long time before I bought my lathe as I wasn't sure I'd make good use of it. Now I couldn't be without it! Along side a mill / router, and a pillar drill there isn't much you can't make.

Zeeflyboy - more great work there with a nice finish to the parts. One thing to bare in mind is adding thumb wheels or other discs adds to the rotational inertia and knocks a bit of performance off the stepper. Not a big deal on yours as the diameter is quite small and for most work the Z is not flying up and down. Just thought I'd mention it in case you were adding some to the X and Y.

[Desertboy]

there isn't much you can't make.

I saw Pacififc Rim the other night and thought one of those 400 foot robots could come in handy for shopping and the like any chance of making me one of them?

[Lee Roberts]

Here is an idea for your lathe to-do list's:



A pen type die grinder or dremel like tool may be less involved for smaller stuff, chuck/collet size being the issue.

[Zeeflyboy]

Oh that's pretty neat! I can add it to the long list of projects lol...

Enough of this manual lathe nonsense, today I fired up the CNC at last and made the top plate for the new Z-axis.

First fixture:




Roughing pass (6mm 3 flute roughing bit, 8mm depth of cut with 1mm axial engagement, 12,000rpm and 1,500mm/min




Finished top side (3 flute, full depth pass 16mm skimming 0.1mm off each pass with a repeat finish pass, 12,000rpm 1000mm/min and a chamfer pass):




Then I drilled two holes for 6mm dowels to align with machine axis, and probed for zero:




Backside ops done:




Finished part with seals and bearing:

[Zeeflyboy]

Guys, has anyone got any experience or knowledge of these spindles I stumbled across?

They are 80mm body and 220v/2.2kw/400hz so should be a straight drop in/drop out replacement (ideal as it makes it relatively easy to switch to 24,000rpm spindle if needed for composites etc). The difference is that they are 1,500-12,000rpm which would be a lot more suitable RPM range for milling plastics, foams, metals etc and opens up the potential to look at thread mills, reamers and makes drilling more viable.

Only downside is they are significantly more expensive than the 24,000rpm garden variety... which makes it less appealing to take a punt!

https://www.aliexpress.com/item/Low-...460.0.0.rut9B3