Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: nobby on June 16, 2013, 05:44:19 AM

Title: spindles and vfd's - so I come out of my 36v power supply..... laymans terms
Post by: nobby on June 16, 2013, 05:44:19 AM
and you have to then have a vfd/ transformer to up it back to mains voltage, as you need it firstly low voltage so you can control the power on and off, and the speed
you couldn't have 110/240v switching and speed control on the break out board.

Also, If you were nailing one together at the moment, and you did not have a spindle or mount, you would simply go for a 80mm spindle mount, so as to choose
1.5kw air cooled
2.2kw water cooled

do the far eastern 80mm spindles have an outomatic collet affair?

being a novice, do I want to be using a 1.5kw spindle firstly, then swap to 2.2kw at a later date, or should I simply go 2.2kw, and run the coolant lines up my flexi-track now and be done with it?

do they not do a baffle aluminium fin type affair for air cooling, that wraps around the spindle, or a  mount that has fins grouves machined into it that can take some finnage?

or even simpler, did they start doing an 80mm spindle air cooled and they over heated , so they liquid cooled them?


Title: Re: spindles and vfd's - so I come out of my 36v power supply..... laymans terms
Post by: ger21 on June 16, 2013, 07:22:58 AM
The VFD will usually provide the 10V you need for the speed control.

I'd go with the 2.2Kw, as it has a larger and more useful ER20 collet.
Or, if you can afford to spend a bit more, I'd probably go with one of these.
http://www.ebay.com/itm/2-2KW-HERTZ-BRAND-SPINDLE-MOTOR-AIR-COOLED-and-2-2KW-ALLEN-BRADLEY-INVERTER-/321108676481?pt=LH_DefaultDomain_0&hash=item4ac3918f81

I know of one user at CNC Zone that runs is 2.2Kw water cooled spindle with no water. For cooling, he has the spindle mounted so that the airflow from his dust collection flows around the spindle, cooling it. I wouldn't recommend this, but he's been running this way for over a year. http://www.cnczone.com/forums/cnc_wood_router_project_log/135232-big_bamboo_-_new_machine_project_started-4.html#post1021198

Adding fins would probably only cool the outside of the water jacket, and not keep it adequately cool.

Just be aware that air cooled spindles are considerably louder at high rpm's.
Title: Re: spindles and vfd's - so I come out of my 36v power supply..... laymans terms
Post by: nobby on June 16, 2013, 08:25:35 AM
Hello,
what I have is.
(http://img.photobucket.com/albums/v222/pantswagen/IMG00727-20130606-1254_zps871b5e3a.jpg)

(http://www.techno-isel.com/tic/Catdas/GantryImages/Enlarge/GantryFB2-A.jpg)
bought used, then have now fitted new nema23's @3.1Nm - wired bi-polar parallel,
then have CW5045 drivers
wish to buy a usb smoothstepper bob = next purchase, then some mach3

primarily to cut wood and plastic

thinking ahead about the spindle, I think stock these use a 800watt kress spindle motor, does that mean they are not switched by the bob, and the speed control is on the router itself?
for now should I simply get one of those, be happy with that cutting wood and plastic,
or get the 2.2kw spindle liquid cooled, lower noise, switchable, 'bigger'? collet, knowing I can mill aluminium. I don't as yet have a mount
is the 2.2kw 80mm spindle too big and heavy for its z axis?
(http://www.techno-isel.com/tic/catdas/GantryImages/Enlarge/ZAxisSlide-A.jpg)



I gather, I need another psu, the vfd, the coolant lines rad and fan, with a pump, swap out the 3 pin metal plug on the 2.2kw for a 4 pin amphenol plastic water proof connection, fit an earth inside. run the power lines to it in heavy sheilded flex/wire,

======================================
ALSO, what is foxing me is it has limit switches on both sides of all the gantries does that mean I can tell mach3 my work area, or is it simply a power of to that drive, so the motor don't squeal like a pig?
 
Title: Re: spindles and vfd's - so I come out of my 36v power supply..... laymans terms
Post by: ger21 on June 16, 2013, 08:42:33 AM
If you want my opinion, I'd go with the Kress.
That's really a small and lightweight machine, and adding a spindle will quickly point out that the rest of the machine is not up to the capabilities of the spindle.
At some point, you'll more than likely want a bigger, faster, more rigid machine. Get a spindle for that machine.
Title: Re: spindles and vfd's - so I come out of my 36v power supply..... laymans terms
Post by: nobby on June 16, 2013, 10:04:59 AM
http://www.youtube.com/watch?v=P6RBLFDJvdQ

oh noise!! 1.5kw water cooled at 67 DB it is then



first thing first them, 12 inches of kingspan enclosure
 :-*
Title: Re: spindles and vfd's - so I come out of my 36v power supply..... laymans terms
Post by: nobby on June 27, 2013, 06:14:39 AM
hello
SHOULD I buy a 0.8kw chinese spindle at 65mm diameter, instead of the 80mm diameter?

about to purchase............

is it a weight lifting issue on the 16mm/5 ball screws?

I don't think I am too concerned about the 20mm collet, as I suppose the max I am to mill is with 1/4'' - 6mm?