My new 6040 improvement plan.

[PaisleyPCdoctor]

Hi,
I recently purchased a China CNC 6040z (2.2kW, 4 axis, usb version with extras) for £1800.
I bought with FULL EXPECTATION AND ACCEPTANCE that it would require some upgrades and tweaks right off the bat. No problem.

I'm starting this thread to post about the problems and solutions s as I do them, in case it might help others in future (the forum spirit :-)

Here is the machine I purchased (attached).

[PaisleyPCdoctor]

My immediate attention was the water pump- threw it in the bin and got a much better and silent pump for £20 off eBay. Old pump binned. Never seen such a crap pump in my life!

[PaisleyPCdoctor]

Second (and probably the biggest of the lot)- SHIELDING- or lack of it!

Absolutely nothing is shielded not even the VFD cable!

I started with external cables to Spindle and Stepper motors.

Supplied VFD cable looks nice flexible rubber 'pond flex' cable. It's plain unshielded 0.75mm2 3 core and earth. The earth wire IS connected to spindle (thank god), but no shielding.

I replaced the entire cable with shielded 1.5mm2 CY control cable. To be extra careful, I also added external copper braid shield. It's now double screened.

I didnt replace the stepper cable, I suply added a copper braid sleeving to the entire length. Obviously, the sleeve is connected to earth....

Actually, no. The aviation connector barrel on the chassis is making contact with paint, not metal. NO EARTH CONNECTION! I had to scrape off paint inside the case to sort that.

Next job is shielding the cables inside the control box, then probably moving VFD to its own enclosure.

[magicniner]

(X) Location, (Y) Location, (Z) Location!
The rest is just window dressing if the first 3 are not worth the cardboard it was shipped in :D

[PaisleyPCdoctor]

(X) Location, (Y) Location, (Z) Location!
The rest is just window dressing if the first 3 are not worth the cardboard it was shipped in :D

Eh?

[pd110961]

Hi Paisley.. where are you in the country mate?

[PaisleyPCdoctor]

Hi Paisley.. where are you in the country mate?

I'm in Paisley. Scotland.

[m_c]

I suspect Nick was on the sauce last night ;-)

But his point was if the basic machine can't hold tight tolerances, then everything is else is superficial.

Shielding is not as big a problem as people often think it is. None of my Denford machines came with anything shielded other than two sensors on the Triac mill. Everything else, including the spindles (VFD on the Cyclone lathe, and DC spindle on the Triac) used unshielded wiring, but then they're not using TTL level logic for inputs.

[PaisleyPCdoctor]

I get that, however, as it's often repeated on this forum- not all China cnc are the same. Much of the reputation was for poor electronics was from early controller boards and VFD etc. I was very careful to get one with a newer controller (HC4-IV), decent steppers and a good spindle. There's nothing inherently wrong with the table and gantry design.

I know my way around electronics, so I wasn't bothered about doing some extra work to improve it. Even without the improvements, it hasn't glitches on me yet. It's done everything I've asked of it perfectly well.

At £1800 it's not the cheapest out there- I certainly wasn't going to spend £10k+

Plenty of people making really cool stuff with 6040's.

[Doddy]

Actually, no. The aviation connector barrel

I've heard these referred to as aviation connectors before now - as I understand it they are used for the headphones on radios. So, yes, they fly, but let's not oversell them. My main concern with them is these (and they are in common use for these machines) is that they aren't really rated for the currents that you might expect. For example

http://www.cliffuk.co.uk/products/cliffcon/zc.htm

You can see these are rated unto 1A. Probably not much of an issue for a small machine - your switching currents are going to be around 1.5-3A, but clearly out of spec for the connectors. My last iteration of <strike>upgrading</strike> updating my controller I replaced all with XLRs.