Chinese 300W DC spindle - is the spindle shaft grounded?

[Clive S]

I have just checked mine and i have continuity between spindle and body. Does that answer the question?

But is this the same type as spindle? ...Clive

[Swarfing]

300W 12V-48V DC High-speed air-cooled Spindle Motor for Engraving Milling | eBay

this is the same type as the one i have.

[HankMcSpank]

I have just checked mine and i have continuity between spindle and body. Does that answer the question?

yes & no...it goes to show that there are some Chinese 300W spindles out there that have continuity & others that don't - thanks for checking though!

These ones on ali express (which seems to be a tad cheaper place to buy vs. ebay) all look much of a muchness, this one looks like yours...

http://www.aliexpress.com/item/Free-...666996832.html

another variant (quite similar)...

http://www.aliexpress.com/item/DC-12...677456541.html


Speaking of importing, I'm probably gonna buy this CNC machine (just the machine & steppers only - no drivers, spindle or VFD etc)....

http://www.alibaba.com/product-gs/82..._for_wood.html

....as I prefer a moving table machine (quieter...the moving gantry machines seemed to be designed like an acoustic guitar - i.e. a big 'soundbox' below the table to amplify the vibrations!) & nobody seems to sell moving table CNC machines anywhere in the UK (Premiersigns did have a similar model - one of which fivetide bought - but even they don't show one on their site now). The Chinese supplier is quoting $1000 delivered by sea which is about £650 + taxes, which for a 3020 ballscrew/ballnut machine constructed from Aloominum(!) seems reasonable.

[asbo]

OK here are some pics of mine.
I've checked again and there is still no continuity between the body and shaft. Although maybe I've lost a few more marbles
There are two screws under the plastic fan thingy on top which presumably would allow it to be disasembled, but I'm not sure you'd get the plastic thingy off without breaking it.
Here is the listing I bought mine from CNC Spindle 300W Motor ER11 collect & Mount bracket Set-in Machine Tool Spindle from Industry & Business on Aliexpress.com

[HankMcSpank]

I've already PM'ed asbo the video, but I'll post it here to so other can have a laugh...



should be ideal for milling 0.5mm pitch pcb packages!

Swarfing - do you use yours? (or have you used it?)

[m_c]

deletedjustforlee

[Lee Roberts]

Thanks for all the info, links and pics guys.

I hope to build a small mill type machine for doing light work, engraving, pcbs and so on at some point so I would like to go with a smaller spindle myself for this unit rather than the bigger units we commonly use for our machines.

My original plan was to build my own spindle like Mark and JB have using an out runner motor, the cost is going to be more then these off the shelf options but I think it may make for a better spindle. After seeing that video of the 2mm run out, I am interested to know if you with these spindles have the same problem with the quality or if or not the guy who made that video just got a duff one?

Here is a video of the kind of thing I’m talking about re going the DIY spindle route:



With a nice link to Raynerds blog post showing the spinde in bits: Brushless Spindle – Part 2 (think he has a link to these forums on his site some place, so not sure if he is a member or not).

Cost will be a bit more but it looks quite easy to do, what do you think?

.Me

[HankMcSpank]

Since the 300w spindles are very common on CNC machines, I reckon there'd be internet 'mob outcry' if all these spindles had runout like the video I linked to earlier (so I can only assume his had been dropped or similar)

asbo kindly applied some power to his spindle & videoed the result - for the sake of a bit of balance, I hope he doesn't mind me linking to it here...



I'm actually buying the spindle from asbo, so I'll soon be able to report how these 300w spindle perform wrt fine pcb milling (vs my present proxxon bfw40/e ...which is fine, but only foes up to 7000rpm & the spindle & brackets weigh in at well over 2kg which is mental for a small machine like I'm using!)

[Swarfing]

Hank the one in the video as a kit is exactly as the one i bought. I've only run it up at 40v as that is the pwm driver o bought to use for it. Looking at it was a disappointment when it arrived. Powering it up was a different matter. It ran rather smooth with no noticeably run out. i will change some of the parts on the driver so i can run it at a higher voltage when i get round to finishing one of many projects.

[HankMcSpank]

Hank the one in the video as a kit is exactly as the one i bought. I've only run it up at 40v as that is the pwm driver o bought to use for it. Looking at it was a disappointment when it arrived. Powering it up was a different matter. It ran rather smooth with no noticeably run out. i will change some of the parts on the driver so i can run it at a higher voltage when i get round to finishing one of many projects.

Cheers for the feedback.

I'm thinking if the fan is removed, then it ought to run much quieter (& possibly smoother) .....it'll be interesting to see how hot it gets & how fast with the fan removed. (the Zen Toolworks spindle doesn't have a fan on the top)...I typically only use mine for 20 minutes stints max - if it runs too hot with the fan off, then I'll even considering mounting a separate larger low noise DC fan suspended over the spindle somehow or other ...this can spin at far lower RPM vs the spindle's & yet should still keep the spindle cool.