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Web Goblin
11-01-2011, 05:25 PM
Hi all,
I have been looking thrugh Google trying to see what spindle motors are available at a resonable cost.
Would anyone like to comment on what spindle motors they use and how good they are?
I will be machining soft and hard woods, plastics and would also like to do aluminium sometimes.
I have had a look at the Kress models, ELTE and a couple of the chinese brand VFDs. Have I missed any?
I have also been thinking about making a belt driven spindle but trying to find a high speed servo might not be too easy or cheaply I might add.

Regards

Ian

blackburn mark
11-01-2011, 05:32 PM
have a look at my build log, iv made three to cover the whole speed range, they are not full proven (bearing life etc) but they do work quite well and are easy and cheap to make
jonathan may at some point work out an interface with mach for these type of spindles

Jonathan
11-01-2011, 07:12 PM
have a look at my build log, iv made three to cover the whole speed range, they are not full proven (bearing life etc) but they do work quite well and are easy and cheap to make
jonathan may at some point work out an interface with mach for these type of spindles

I'd forgotten about that, sorry! I will look into doing it again with that servo controller soon.

I've got a bit closer with my brushless motor spindle. The chuck and ER16 collets finally arrived yesterday.
(Edit - if you saw the comment with regard to running it from VFD ignore it)

Still got to get a 12s 100A ESC for it and something to power it. Best I've got is a 6s 100a and 24v 92Ah VRLA battery. That'll get 3000rpm - so enough for some things.

blackburn mark
11-01-2011, 09:01 PM
I'd forgotten about that, sorry! I will look into doing it again with that servo controller soon.

dont flapp about it jonathan, like i said, when it comes up on your list of stuff to do that will be soon enough :)
iv been using my larger spindle to fly cut, loving it :)
i use all three spindles at diffrent times, im well chuffed with them

Jonathan
11-01-2011, 09:44 PM
i use all three spindles at diffrent times, im well chuffed with them

At different times, you're not really trying :lol: get them all cutting at the same time! Would be amazing for making lots of identical parts (PCBs), and actually affordable.

keith77777
18-02-2011, 01:03 AM
Spindle motors are they expensive. I recently looked at straight shaft collet shafts £20 with a view to belt drive from a variable speed 1 hp washing machine motor www.calenterprises.co.uk/speed.html (http://www.calenterprises.co.uk/speed.html)

wiatroda
18-02-2011, 09:38 PM
Recently I've made myself new spindle. two taper bearings, ER20 shaft, belt and motor. cheap and very good solution. You can see it at http://malamuterun.co.uk/homemade_cnc_mill_spindle.htm . Maybe this will help a bit

Jonathan
18-02-2011, 09:46 PM
It looks like you're only stopping the shaft of that spindle from moving axially with a grubscrew. Are you sure that's strong enough? Might be difficult to preload the bearings with that arrangement.

wiatroda
18-02-2011, 10:17 PM
It looks like you're only stopping the shaft of that spindle from moving axially with a grubscrew. Are you sure that's strong enough? Might be difficult to preload the bearings with that arrangement.

Jonathan there is two grub screws and I used Truloc shaft retainer as well both on shaft collar and the top bearing. But the forces act on shaft up the spindle or sideways, but not down(trying to tear the shaft off from the spindle, if I can put it in this way). So far it worked well for quite few hours with no problems at all. If something changes I'll post info asap

Web Goblin
18-02-2011, 10:49 PM
I have had a look at various bearings for making a high speed spindle and they cost a small fortune. I can get a set of 15000rpm bearings for £40 for 4 so I might go that way and give it a try.

Ian

m_c
19-02-2011, 01:36 AM
Jonathan there is two grub screws and I used Truloc shaft retainer as well both on shaft collar and the top bearing. But the forces act on shaft up the spindle or sideways, but not down(trying to tear the shaft off from the spindle, if I can put it in this way). So far it worked well for quite few hours with no problems at all. If something changes I'll post info asap

A heavy sideways load will cause the shaft to pull down if the shaft isn't secured well enough.
How did you manage to preload the bearings if you only used grub screws?

wiatroda
19-02-2011, 10:48 AM
How did you manage to preload the bearings if you only used grub screws?
The ER20 have threaded hole at the end (you may see it on web pics). I've just put another steel bush onto the shaft, put some load with screw pressing bearings towards each other. Truloc bounds within one hour, but I left it overnight. While I inserted a shaft seal on the coupling end, I left the other end without. The next day I filled spindle with oil leaving air gap that makes allowance for oil temperature expansion and then I put the seal on.
The only thing I would change is to replace the whole strait shaft chuck for tapered one. Of course I would then have to change the whole design: instead of unscrew chuck nut to replace tool I would replace the whole chuck with another one. That would make it a bit faster and there would be no need for Z axis resetting or at least I would know the offset. I'm not sure my lathe would handle bigger dia bars, definitely not my budget. It's quite exiting idea to try to produce this kind of spindle thou.

keith77777
19-02-2011, 11:55 AM
Recently I've made myself new spindle. two taper bearings, ER20 shaft, belt and motor. cheap and very good solution. You can see it at http://malamuterun.co.uk/homemade_cnc_mill_spindle.htm . Maybe this will help a bit

Yes thats a very good solution ! I cant see the point in using routers etc when you know they wont stand the strain. However I saw that in some of the ads the spindles had threads thro the draw bar hole in the centre could this be used to retain the bearings and a pulley ?

Any wanting to make from scratch could of course cast an aluminium bearing housing.

Best regards Keith

wiatroda
27-02-2011, 01:16 PM
the draw bar hole in the centre could this be used to retain the bearings and a pulley ?

Best regards Keith

Keith, did you mean something like this ???
3803
BTW, my grub screwed shaft collar is still keeping strong. Nothing got loose so far. While I'm writing this the machine is cutting out some profiles from 3mm mild steel :). Recently I had an idea to make CVT to transfer power from motor to spindle. Few problems are bugging me: high cost of materials to make a 150mm dia pulleys and availability of multi-speed belt( like this http://www.gates.com/index.cfm?location_id=3106).

Lee Roberts
17-11-2016, 09:48 AM
I have had a look at various bearings for making a high speed spindle and they cost a small fortune. I can get a set of 15000rpm bearings for £40 for 4 so I might go that way and give it a try.

Ian

Did you build one in the end Goblin?

Web Goblin
20-11-2016, 03:31 PM
Lee,
no I never did get one built. As per usual ended up working on something else and the idea got scrapped. At the moment I can t get enough time to finish my rebuild, but I have started thinking about a diy VMC build.
For some good news though I am off to Germany on Tuesday for the factory acceptance tests for the companies new £1M Laser. I cant wait to see it running.