Buying a Chinese 6040 Router

After reaching the limits of what my Comgrow RoboCNC could mill, even with a 600 watt brushless motor upgrade, I decided to get a larger CNC router. Something that would have a chance of cutting aluminum.

eBay is saturated with beige 6040 routers for $1200 and up, but I zeroed in on the more expensive China-Zone brand for a few reasons. One is that they had a model with extra Z height (150mm), and I was pretty sure I would need that if I added a spoilboard and/or vise. Two is that they possibly would take extra care in parts and assembly as they had a brand. Three is that I liked the bare aluminum look over the painted brown look. Four is a guy on YouTube had a brown one and his Z axis was not rigid – this ChinaZone one does not have that issue. Maybe none of the other brown ones don’t now either, I don’t know. Five is ChinaZone has discrete stepper drivers, and I have seen others that have them integrated with the motion card, which makes it much harder to upgrade the motion card.

Once I knew that I wanted the extra Z, the 4th axis, 2200 watts, and the wireless pendent, I compared the various listings. They all had different seller names, prices, and delivery times. Turns out they are all sales reps for the same company. I placed an order for one that was $1750 and free shipping from NJ/CA.

Someone promptly wrote me back and said they were sold out of US inventory, and they could send me one from China but it would take 4-6 weeks. I declined, and then placed an order with another listing for seemingly the same item. They also wrote me – this time from What’s App, and also said out of stock in the US, but offered to send me one from China via Fedex within a few days for $200 more and no import duty. Knowing this machine is over 100 lbs and that I would save sales tax, that was a good enough deal to not have to wait. In fact my friend in China who ships machines to the US said he sometimes spends $600 to ship a 70kg package. I was suspicious as to why they didn’t show out of stock on eBay, but after they contacted me, I did see that they updated the listings to show shipping was from China, so it seems to be an honest mistake due to many salespeople sharing the same pool of inventory.

I said ok, and they asked me to send money via PayPal rather than eBay as they could only absorb some of the extra shipping cost if they didn’t have the eBay fees. I realize this would scare some people, but I could tell it was legit – I said ok, but asked them to send a PayPal invoice with a full list of what I was getting so that I would have purchase protection. They agreed. I had to help them write the invoice to my satisfaction (there is no purchase protection on industrial machinery, so I had to had it say it was a hobby engraver). I paid them, and got a tracking number from UPS. After a day, UPS kicked it back, and said the machine was too magnetic to fly (the spindle). They reshipped it by Fedex. After about a week, I had the machine.

First problem was they shipped a parallel cable rather than the USBCNC cable I requested. This brings up a bad choice I made. I assumed that the option that worked with USBCNC over USB would also work with Mach3 over USB, so I picked that card figuring I was getting a two-for-one. I was wrong. It works with (an old version of) USBCNC over USB but Mach3 *only* on parallel. I should have picked their option for Mach3 over USB. In any case, they shipped me a new cable via air, and it came a week later.

To avoid waiting, I bought some parallel to USB cables from Amazon, and none worked. So, I didn’t wait and got it working with the parallel cable and Mach3 (I later learned that LinuxCNC would have worked also). This was quite hard as I had to find an old PC and find a way to install 32 bit Windows 7 – plus I had to buy a $20 parallel port. Even then, it didn’t work at the documented profile settings. I had to learn on my own that PCI parallel cards use a custom memory address that differ from the instructions. Took a few days to figure out – how to find the address, etc.

I got it working, and many of the settings I had to use in Mach3 to get it working well differed from their instructions. Why they don’t just send everyone a working Mach3 profile, I will never know. Also, I eventually got the pendent working, but they never sent the driver to me, so I had to hunt that down. They could make this way easier and more turn-key. Seems like whenever they sent drivers, they were either not the latest one. As if no one there was maintaining a support package.

All seemed well at first, but sometimes steppers would lose steps. I noticed that the discrete stepper drivers were set to a rather low current setting. I turned them up to just over 3 amps, and when running, the steppers never got much over 40 degrees C. Steppers can easily run over 70C or more, so that seems good to me. This didn’t fix the problem though. I searched around, and found a post from 2012 where a guy said he had this issue and solved it by moving his 48v power supply out of the enclosure. I don’t think he needed to do this. I found the manual for the stepper drivers, and it said to use twisted-pair wire to help with interference. I changed my X and Y wires to twisted pair, and my problem virtually went away. But, I am not sure that it was the wire, because I also tightened many surprisingly loose terminal screws – so possibly the connection was being lost. Also, the parallel cable they gave me was not shielded. Amazon has $10 shielded ones, so I ordered one of those. Also, I ordered $10 in copper foil tape with conductive adhesive so that I could wrap all of the wires. The VFD cable appeared to be unshielded. It should be shielded, and also should only be grounded on the controller end. They did a really clean wire job in the controller, but didn’t do much related to EMI – although they did have choke magnets.

Meanwhile, this is a water-cooled spindle. I am glad that I have the 2200 watt one as even with this power, I still stalled it twice. It’s not as much power as you would think, or probably not even what they claim – so I wouldn’t suggest the 800 or 1500 watt option. Also, the smaller motors don’t use the collet size that can accept 1/2 inch.

It came with a spindle cooler pump, and you normally fill a bucket with water, and it circulates that. Problem is, the water would get very hot. I almost burned my hand – had to be over 125 degrees F. I ordered an “industrial chiller” for about $140 from eBay. It works great! The water never went over 35C after that. I should also note that I have owned two higher-end ~$400 laser chillers that had actual compressors and refrigerant in them. That is not needed for this. The $140 one is good, but you will need some tubing adaptors. I 3D printed mine, but Amazon has some brass ones. Get the chiller.

But, I ran into another problem. If I set Mach3 to 25kHz, it seemed reliable. At 35Khz, it was mostly, but not perfectly reliable (it would run for many hours). At 45khz, it was not reliable enough (would sometimes fail with 3 hours). So why not set it to 25khz? That was limiting my rapids to about 1200mm/min or about 40 inches/min. I decided that parallel port was a dead end, due to speed and also due to needing 32 bit Windows – and the USBCNC cable they provided me with did not work with any Mach3 plugin.

I looked into other motion controllers, and my conclusion is that the best would be either a UCCNC 300 or 400 Ethernet controller with breakout board (which would cost about $180 and work with both Mach3 and UCCNC software), or a $160 Mesa card, which would only work with LinuxCNC. I wasn’t sure I was up for configuring Linux on my one machine that I was using every day, and I didn’t want to wait for a shipment from Europe for UCCNC, so I got a $27 USB card from Amazon. That took me around an hour to install, and it worked. Only negative I saw is it only has 4 inputs. That is enough for XYZ limits and probe, but nothing is left for a 4th axis optical switch, or a water alarm switch. Not a big deal though. I am pretty happy with how it is working. Rapids are at about 2600mm/min now. Homing also works once you get the settings/limits figured out (hint – go into the plugin settings for the motion controller and you may have to adjust how much it moves backwards after it hits the limit switches). Also, get “limits” set up properly.

For Mach3, the UI is way too ugly to use, but this guy solved that with a nice screen set:

Now that it is all working well, I will say that the size is good as it fits brilliantly on a Harbor Freight cart that has room for the controller, the chiller, and a PC on the bottom. But, the few times I wanted to make signs, the size was marginal and I was fighting over every last mm. Whenever I am making signs, I wish that I had a OneFinity X-50. So why did’t I get a OneFinity? Partly because I ordered the 6040 before I knew about it, partly because the OneFinity is $3000 by the time you add a water-cooled spindle, and partly because there is a long wait to get a OneFinity. In any case, it would use up a lot more space. Why a OneFinity over the competitors from Carbide3D? It is vastly easier and quicker to assemble, and I like how it uses ballscrews over belts. Speaking of size, is it really a 6040? Between the limit switches, I came up with the largest practical soft-limit settings of 390×570 – so no. Ideally it would be nice if they designed the machine to truly have a cuttable area of 400×600.

About enclosures. I was pretty sure I would need one, but I really don’t. I got a dust-shoe from Amazon that sometimes works great when connected to a Shop Vac through a HomeDepot dust separator, depending on what I am cutting. Also I run a Honeywell HEPA air filter in the room.

In summary, I am happy with the machine, but I spend many days fighting with it to get it going, and it all could have been avoided if they hired a truly native English speaker who knows about this stuff to clean up their documents. They spoke English nearly perfectly, but not enough to make unambiguous documentation.