Thanks Arty. The sympathy in appreciated, but not necessary and not solicited. I am just giving some cheap advice.
Good luck with your order. Maybe you will get one of the better machines. While some of them are probably ok, but I only get to purchase one at a time and so the QC is the luck of the draw. Since so much of the Chinese machines are probably made by hand (some untrained/unskilled guy drilling holes or working with poor tools... etc.) I think it just depends on who is making your machine and what kind of day they are having. For example, I think they probably just use a paper or wood template to mark the locations and a hand drill to make a lot of the holes... and so sometimes even the simplest of things are not aligned... like motor mounts where only three of four holes actually will take a screw! Or a lead screw crank handle mount that has two alignment pins but only one of them fits in its hole or is even drilled out. I think the most serious thing with my machine are that the gibs were cut wrong (long length, not flat, bowed, and the wrong taper... not much else could be done incorrectly) and more seriously the ways are not straight and certainly not parallel. I have worked on the gibs and got them somewhat fixed for now.... and I am slowly sanding (scraping) the ways, and measuring a LOT trying to get them parallel. They are getting better, but you have to sand a long time (days) to take off a few thousands of an inch off over a small area on a hardened way. By the way, if the ways are not made right then the x-y-z axis are not square and may have sloppiness (loosely-fitting... moves around) in their perpendicularity. If you tighten down the gibs to get rid of some of the sloppiness in the squareness, then the backlash gets really bad. For example on my y-axis I tightened the gib down to optimize backlash to about 0.0025- 0.003" when the table is near the column, but then when the table was moved out a few inches the backlash increased > 0.020" (I did not move the table any farther out as I was afraid I might crack the cast iron saddle as the gib was so tight). So you loosen the gib to get the backlash down over a reasonable travel length and live with the sloppiness. I even found that the E-stop switch was wired incorrectly. (Unsafe!) The list just goes on and on. Oh well you can learn a lot by trying to fix things. If I had it to do over, I would not buy a mill from China. You will note that when I purchased my PM1440GT lathe I made sure it was not from China.
Dave L.
Good luck with your order. Maybe you will get one of the better machines. While some of them are probably ok, but I only get to purchase one at a time and so the QC is the luck of the draw. Since so much of the Chinese machines are probably made by hand (some untrained/unskilled guy drilling holes or working with poor tools... etc.) I think it just depends on who is making your machine and what kind of day they are having. For example, I think they probably just use a paper or wood template to mark the locations and a hand drill to make a lot of the holes... and so sometimes even the simplest of things are not aligned... like motor mounts where only three of four holes actually will take a screw! Or a lead screw crank handle mount that has two alignment pins but only one of them fits in its hole or is even drilled out. I think the most serious thing with my machine are that the gibs were cut wrong (long length, not flat, bowed, and the wrong taper... not much else could be done incorrectly) and more seriously the ways are not straight and certainly not parallel. I have worked on the gibs and got them somewhat fixed for now.... and I am slowly sanding (scraping) the ways, and measuring a LOT trying to get them parallel. They are getting better, but you have to sand a long time (days) to take off a few thousands of an inch off over a small area on a hardened way. By the way, if the ways are not made right then the x-y-z axis are not square and may have sloppiness (loosely-fitting... moves around) in their perpendicularity. If you tighten down the gibs to get rid of some of the sloppiness in the squareness, then the backlash gets really bad. For example on my y-axis I tightened the gib down to optimize backlash to about 0.0025- 0.003" when the table is near the column, but then when the table was moved out a few inches the backlash increased > 0.020" (I did not move the table any farther out as I was afraid I might crack the cast iron saddle as the gib was so tight). So you loosen the gib to get the backlash down over a reasonable travel length and live with the sloppiness. I even found that the E-stop switch was wired incorrectly. (Unsafe!) The list just goes on and on. Oh well you can learn a lot by trying to fix things. If I had it to do over, I would not buy a mill from China. You will note that when I purchased my PM1440GT lathe I made sure it was not from China.
Dave L.