K2 KT4014 Servo

[kjmdes]

After purchasing half a dozen machining centers over the past twenty years, I was pleasantly surprised at what seemed a very stout and well thought out low cost machine.

Didn't last long.........

Comm before the sale was less than encouraging, but I figured I could deal with it since I'd done enough CNC to work out the bugs if there were any. After sales was a nightmare, and I haven't heard a word for months now.

The machine arrived with a busted limit switch. No problem. Then I noticed all the stainless fasteners. Stainless and aluminum? With loctite?. Well, I could overlook that, but when I started to pull fasteners, I found the entire, and overly massive Z-axis was held on by 12 threads distributed through (4) fasteners. As I dug into the machine, I found that most fasteners were short, and that the loctite, as it was applied to them, engaging just three or so threads, had bunged up those threads. I went through the whole machine, chased the threads, replaced the fasteners, and assembled it wet where appropriate.

Once I powered it up, it sounded like the X and Y axis were coming apart. I found that the lead-screw-to-brg diameters were mismatched, by .008. Clank, clank, clank. I shimed these.

Then I noticed the slots in the optional extruded table were not evenly spaced. I suppose this bothered me more than anything, as it makes setups in the CAM program a total pain.

I rarely complain about machines, service, etc. But when I went to the trouble of writing a few pages of observations, suggestions, etc., all but one guy blew me off. He admitted they had issues with the leadscrews and possible problems with fasteners. I asked if they could send replacements, they sent three limit switches and that was that.

Needless to say, no more K2 machines for my biz. I've had far better service from Chinese vendors, as much as I regret saying it.

KJM

[jeffery926]

After purchasing half a dozen machining centers over the past twenty years, I was pleasantly surprised at what seemed a very stout and well thought out low cost machine.

Didn't last long.........

Comm before the sale was less than encouraging, but I figured I could deal with it since I'd done enough CNC to work out the bugs if there were any. After sales was a nightmare, and I haven't heard a word for months now.

The machine arrived with a busted limit switch. No problem. Then I noticed all the stainless fasteners. Stainless and aluminum? With loctite?. Well, I could overlook that, but when I started to pull fasteners, I found the entire, and overly massive Z-axis was held on by 12 threads distributed through (4) fasteners. As I dug into the machine, I found that most fasteners were short, and that the loctite, as it was applied to them, engaging just three or so threads, had bunged up those threads. I went through the whole machine, chased the threads, replaced the fasteners, and assembled it wet where appropriate.

Once I powered it up, it sounded like the X and Y axis were coming apart. I found that the lead-screw-to-brg diameters were mismatched, by .008. Clank, clank, clank. I shimed these.

Then I noticed the slots in the optional extruded table were not evenly spaced. I suppose this bothered me more than anything, as it makes setups in the CAM program a total pain.

I rarely complain about machines, service, etc. But when I went to the trouble of writing a few pages of observations, suggestions, etc., all but one guy blew me off. He admitted they had issues with the leadscrews and possible problems with fasteners. I asked if they could send replacements, they sent three limit switches and that was that.

Needless to say, no more K2 machines for my biz. I've had far better service from Chinese vendors, as much as I regret saying it.

KJM

I guess they still are making them the same old way. I purchased a 3925 about five years ago and had major problems with mine too. Hardware loose and screws were to short, out of square linear rails, 3/8" aluminum table, no where near being flat, ball screw bearings spinning in housings causing major backlash, same problem with 4th axis, weak frame causing vibration just making light cuts, servos acting like steppers where they would get lost, router was bolted to a crooked out of square, welded steel table they made for me which made the router way out of whack also. The ball screw bearing housings were not even parallel with the linear rails causing drag and excessive wear. I looked at the Chinese routers at first, but thought I would get better quality from a USA made machine.

WRONG!!!

I have spent over 150 hours and about $1000.00 straitening everything out on the mechanics and accuracy of this machine.

I pointed out these issues with them back then too, but it sounds like they did not listen and continue on making them the same old way.

[doorknob]

Then I noticed all the stainless fasteners. Stainless and aluminum? With loctite?.

What was the basis for your concern about the use of stainless fasteners with aluminum? Is it galvanic corrosion or something else?

I know that aluminum alloys and stainless steels are somewhat far apart on the galvanic series charts, but wouldn't that only be a corrosion concern in the presence of an electrolyte? Would the loctite act as an electrolyte, or is there a different concern over the use of loctite? You are not using a liquid coolant, are you?

I'm curious because I had not previously worried about using stainless fasteners with aluminum in such an application (and I have previously used stainless nuts and bolts with aluminum parts in various electronic projects).