Lifting the machine with a hoist or crane is a challenge. To do it I ended up using 4 identical 30" lifting slings and S hooks. (use heavy duty hooks) I placed a hook in the holes at the front and rear of the machine itself. I used forklift so had two slings on each fork to lower it in to position. I lifted the base along with the mill, the base isn't that heavy but check that the mounting bolts are installed properly.
Most of the problems with the machine relate to the spindle motor. The original motor and VFD (drive) supplied by Sangmutan had serious problems that make the mill almost unusable. The problem was very little torque at low speed and slow spin up. The problem was acknowledged by Sangmutan last December but it took until August before replacement VFDs came available.... or at least until Novakon sent me a replacement. With the revised VFD the machine is much much better.
The machine is not a $200,000 Haas or even a $20,000 machine. Just like every other piece of Chinese equipment priced at the low end of the market there are defects to be found and repaired. Silly things like cheap screws that strip the first time you remove them are easy to fix. Rethreading a hole that didn't go deep enough to tighten up only takes a couple minutes. The problem is discovering what needs to be addressed. My mill had a problem with 0.008" of lash in the Y-axis. Novakon was pretty quick to suggest tightening the jam nut on the ball screw to eliminate any gap in the bearings. Didn't work. Asked for a replacement ball screw and they agreed to send me one but it took several weeks. (I suspect they didn't have any stock and had one shipped by boat from China.) When I pulled the machine apart to replace the ball screw I noticed one of the bearings was installed backwards so no amount of adjustment was going to correct the problem. Unfortunately the bearing race was damaged from being used incorrectly so I had to replace both bearings. With that done the lash is down to about 0.002" which I identified as being caused by the rubber spider coupling to the motor which I will address with some shims.
Electrically and electronically the machine is made with good quality components. However the workmanship on the wiring is a problem. Common failures are wires pulling out of connectors or off terminals. Besides my machine I have see two other NM145s and the routing of the wires is different in each. There are many places for a wire to get snagged or pinched. I found conduit fittings that were left loose and even a nice screw driver left in the cabinet as if the worker left for lunch, had a couple beers and forgot where he left off so closed the panel and sent the machine on its way. Better workmanship and attention to details would prevent many of the problems customers find as time goes by. The good news is 30 minutes of you time spent looking at and tugging on each and every connection will catch most of the problems.
The discounted price is tempting especially if you go in with the mindset that what you are buying is a assembled kit that you are going to inspect and adjust before use and not a finely tuned piece of equipment ready to use. I paid closer to the regular price and even with the cost of stuff I opted to replace it has nearly paid for itself in less than 6 months.
Novakon got it about 90% right. What is lacking is documentation such as an exploded parts diagram, wiring diagram and some written up procedures. They try to provide support but without these materials they must start over and go one step at a time for each and every customer that calls causing their support staff to get overwhelmed quickly and loose track of what each customer needs to get their problem resolved.
Charlie.


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. I have just given up on the dc spindle and am in the process of installing a 3 phase ac motor. as for the other electronics they are fine i have gecko g203v drives on all 4 axis (i have a 6" rotary table also from Novakon) and cnc4pc c11g to interface the computer (also from Novakon) to the steppers its really a decent setup for control the only real goof was specing the dc drive that large. I have heard other companies use similar drives on other machines but they are smaller and seam to be reliable but this model SUCKS (sorry I got to call em' as I see em'). Another thing I would change is the home switches. the non contact sealed switch seams like a great idea but in practice it just dont seam to work spot on every time. good enough to get by but i would like mechanical snap action switches better i think. Also the machine does not have limit switches. so the limits have to be set with the soft limits within mach but i would rather have real LIMIT switches. one of my last gripes is on my machine the cabinet and machine came together and when i added coolant it leaked out the mounting hole or something and was loosing maybe a gal of water every 2 hrs. i had to keep a mop nearby to suck the coolant off the floor. i ended up running a bead of caulk around the entire base of the machine to keep the coolant away from the mounting holes. 