Chinese 2.2 water cooled spindle / Which VFD ?

[dudz]

Just purchased my used CNC/routing machine. It has a 250w spindle. I want to replace the spindle with a 2.2kw Chinese one. I have read several times that the VFD that comes with these are rubbish. Is there one out there (maybe ebay) that is relatively cheap that will do the job, and last longer than the Chinese VFD ?

any links would be very helpful. Thanks

[Jonathan]

I think you'll find most of the posts saying the Chinese VFDs are rubbish are either old, or someone quoting from an old post. There's been at least one design change in the VFDs recently, which implies they are better. Either way I've connected them up for a few people and they've worked fine, plus I'm currently using two - one the router and one on my lathe and haven't had any problems due to quality of the VFD. In addition I bought one a few weeks ago for another CNC router, and that's fine... so I wouldn't worry about it.

[dudz]

Ah, OK. That's useful thanks . It would be helpful if the Chinese Ebay sellers, would mark up which model they are selling. They seem to put reference numbers in their titles, but don't explain them. How does anyone know which are the latest versions of each item ?
Please can you recommend an ebay seller for the spindle/VFD package ?

[MikeyC38]

Hi Jonathan
Could I ask which ebay seller you got yours from? I'm nearing the start of my project and it would be useful to know. There are some sellers that claim to ship from the UK. Is this true?

Thanks
Mike

[dudz]

I have actually just bought a Kress 1050FME as my machine has a 43mm holder. I am going to buy a SUPER PID for the controller www.SuperPID.com - Super-PID Closed-loop Router Speed Controller (http://www.vhipe.com/product-private/SuperPID.htm)
I might upgrade to a Chinese spindle later, when I learn how to use all the software.

[wilfy]

when you factor in the cost the kress and the super PID your at 2.2kw spindle money anyway.. why would you buy the kress when the WC spindle is so highly recommended and accepted as far more reliable? i hope u got it cheaper than the prices i can find

[dudz]

I got the kress here : DamenCNC.com - KRESS Milling Motor (http://www.damencnc.com/en/tools/kress/kress-milling-motor) Which saved me a bit.
I don't like buying anything Chinese. I would of had to buy or make a new Z plate as well.

[wilfy]

ok thats not a bad price, but with the controller not far off the 2.2kw spindle... and it was u who said u were going to buy one... i understand the logic in saving yourself a bit of money now in the short run as it doesnt hurt so much.. but sometimes u just have to sit tight save the pennies a little longer and be much better off for it..

[dudz]

In my logic, If I am offered something Chinese , I want it dirt cheap. As they haven't exactly set the world trademark for quality. I have 3 Chinese dirt bikes, very good price, but once left out in the rain, the lack of quality of the steel and chrome really shows. After 2 years, 60% of the parts needed replacing. No money saved there. I knew I should have bought Japanese !
I have watched countless youtube videos, and it swayed me more towards the Kress. For small jobs in Alu they seem very good.
I am just a beginner in the Diy CNC hobby, and I'm sure I will learn by my mistakes.

[Jonathan]

In my logic, If I am offered something Chinese , I want it dirt cheap.

The 2.2kW spindles are dirt cheap compared to buying from the UK (http://www.arceurotrade.co.uk/Catalogue/High-Speed-Spindles-Motors-Inverters)/USA/Germany etc from a recognised company.


I have actually just bought a Kress 1050FME as my machine has a 43mm holder. I am going to buy a SUPER PID for the controller www.SuperPID.com - Super-PID Closed-loop Router Speed Controller (http://www.vhipe.com/product-private/SuperPID.htm)

That's a shame... The Kress will have much (in order of importance) poorer rigidity, worse runout, more expensive collets, lower lifetime and be noisier. If you're using it for aluminium it will not last long since it's still just a router (albeit a good one), not a proper spindle, so the bearings are a lot smaller among other things.
Before I got my 2.2kW spindle I was thinking of getting a Kress and I'm very glad that people on this forum persuaded me to spend the extra as the 2.2kW spindle has been faultless.

[dudz]

Ok, you win ! .... I know you people have far more exp with these things than myself. I have canceled my order for the Kress, and I am ordering the Chinese spindle and VFD.

[Jonathan]

Ok, you win ! .... I know you people have far more exp with these things than myself. I have canceled my order for the Kress, and I am ordering the Chinese spindle and VFD.

:) I'm sure you wont regret it. You'll probably want to get these to go with it:
Brand new precision ER20 collet set 12pcs (2mm-13mm) | eBay (http://www.ebay.co.uk/itm/Brand-new-precision-ER20-collet-set-12pcs-2mm-13mm-/281014512375?pt=BI_Tool_Work_Holding&hash=item416dc52af7)

[dudz]

Thanks Jonathon. Please could you post a link to a set of bits/endmills that would be used for Alu with this setup. ?

[Jonathan]

Depends on what you're cutting of course, but for general 2.5D machining I use the 6mm single flute (http://www.ebay.co.uk/itm/5X-6mm-CED-Carbide-CNC-Router-Bits-Single-Flute-Tools-CEL-22mm-/190680677473?pt=LH_DefaultDomain_3&hash=item2c65743c61) cutters. I quite regularly use the same style cutters from 3mm to 8mm. The tool deflection is proportional to the length of the tool to the power 4, so a small increase in the length of the tool can lead to a much higher deflection and thus poorer finish, hence you should always buy the smallest ones you can use, so ideally keep a selection...

[dudz]

is that the same bit for "rough cutting" and "finishing" or is there no such thing on Alu ?

[Jonathan]

is that the same bit for "rough cutting" and "finishing" or is there no such thing on Alu ?

Yes, for roughing use it at whatever the maximum depth the machine will tolerate is, but leave the part 0.1-0.2mm oversize. Next do a finishing pass the full depth in one cut, which just removes the 0.1-0.2mm.
13000rpm @ 600mm/min is a good speed for the 6mm single flute tool. Start with a smallish depth and work up, keeping the feed and speed the same, until you find the limit of the machine/cutter.

Roughing cutters do exist for aluminium. They have a serrated edge which is designed to break the swarf up into small pieces which can easily be washed away by flood coolant.

[dudz]

What do I use for drilling and countersinking Alu?... seems a daft question. I want to make a new Z plate soon, to hold the Chinese spindle, as the one on the machine is only 100mm wide. The spindle holder for the Chinese one is 140mm wide. So I need to accurately drill the holes for mounting on the machine and for the spindle holder. Links on ebay would be fantastic if poss.

[wilfy]

i'm not sure about countersinking so hopefully someone will jump in.. but drilling alu is very easy as it's really quite soft, any HSS drill bit should be good enough, just pilot with a 3mm or similar first then open it up with the right size bit for your bolts and even tap it with standard taps if you want it threaded

[Jonathan]

You can countersink it with some countersink bits that would be used on wood, but the ones designed for metal do work better. Don't countersink the holes since the bolt will align to the hole if it's countersunk, so you have no room for adjustment which is important to get the spindle aligned properly (i.e. in tram). If you need the head of the bolt below the surface of the aluminium, then counterbore the holes and use socket cap head bolts.

Other option is to make a 100mm wide spindle mount. If you can bolt it from the back then it shouldn't be too difficult. I've made one that's 110mm wide.

[dudz]

Thanks for the answers, I thought the plate was 100mm wide, but checked just now....its only 82mm.
Problem is.....With the 250W router the machine has at the mo, making a spindle mount might be a bit a of a large job.
Anyone fancy making me one (payed of course) ?

Other than that, I bolt a 10mm thick / 140mm wide piece of Alu on the face of the Z plate and bolt the Spindle mount to that ? That way there will be 20mm of Alu behind the Spindle mount. What do you think ?

[stuboy]

I have a Siemens Micromaster 420 on my 2.2Kw Chinese spindle, have mach3 controlling it just my breakout board frequency to voltage converter is not linear as far as i can tell!
Cheers
Stuart