I bought one of these off ebay and I wanted to share my experience with it in case anybody else is thinking of buying one. There seems to be little information available on the net. I was going to post it to CNCzone, but i never got my confirmation e-mail when I signed up, so I don't know what happened there.
For the record, I'm using EMC2 under Ubuntu, engraving acrylic 2mm deep at 300mm/m.
I'll start with the one part of this post that makes it belong in a machinist forum. I've heard complaints about lack of rigidity. IT'S A ROUTER! IF YOU NEED A MILL, BUY A MILL! The table on the thing isn't even flat. I use mine for etching acrylic and making circuit boards. Don't expect much more than that from it.
If you decide to buy one, realize that all those broken English promises at the bottom of the listing are useless. I enquired about spare parts, and of course, heard nothing. You get the full guarantee, if it breaks in half, you get to keep both halves. The instruction manual is almost non-existant and makes no sense in two languages.
The clamping setup provided is almost useless. The nuts are square, so they just rotate in the slots. I used some 1/2" X 1/8" cut to 3/4" lengths to make new nuts.
Now, the problems I've had. First thing to fail was the X channel on the breakout board. Good news is, they had circuitry for the A channel. Bad news is, their was no connector for it. So I unsoldered the connector from the X channel, moved it to the A channel, and reconfigured EMC2. Warning! This is a multilayered board, and it's not easy to get that connector off without melting it. If you need to try this trick and you are not familiar with soldering multilayer boards, find someone that is.
Next to go was one of the spiral cut aluminum motor couplings. So I found some of the couplings that are aluminum bushings with a stainless steel bellows in between. Didn't last much longer. So I've gone to a solid coupler.
In the middle of one project, the Z axis quit. After much time with an ohm meter, I found there was a broken wire somewhere in the harness, not at an end or flex point where you would expect a break. Very strange. I ran a wire to bypass the break.
Now here's where it gets strange. Apparently, when I set up the EMC2, I used stepper settings that came with the software. I made a great many items, then suddenly started losing steps in the X axis. Swapped breakout channels, swapped driver boards, swapped stepper motors...nothing. Went back to the instructions and saw their setup numbers were a little different. Changed those and off it went. Beats me.
Now for some upgrades:
One of my concerns has become lubrication. There's no mention of it in the instructions, no surprise. I've been putting light oil on the lead screws and slide bearings, but the ones under the table for Y axis are hard to get to. Might even drill some holes in the table so I can get some oil to them. If anybody has any ideas in this area, I'd appreciate them.
I use some software I wrote to convert BMP files into G-code. It's mostly a left to right kinda thing, so the X axis gets a good workout. I notice the motor gets plenty hot, so I'm going to put heat sinks and a cooling fan on the X axis motor.
I hope my ramblings will help someone in the future with their decision on whether or not to buy one of these. I purchased this machine to start a small business. If the business takes off, I will definitely be in the market for a larger and more robust router. But now that I have all the kinks worked out, it seems to be working well.
Best of luck.