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Well the more I learn about "cheap" Chinese mini-lathes, the more I wish I either bought a Harbor Freight or a Cummins (or whatever I could've gotten for the lowest price), or spent more money for a better machine.
I bought this one under the mistaken notion that the MicroMark "MicroLux", unlike the other varieties, was pretty much usable "right out of the box" (after some minor assembly).
Yet when I first assembled it, for example, I found I could barely move the carriage with the hand wheel. It was my first lathe, yet I knew something was wrong there. In order to fix it, I had to put shims beetween the apron and the saddle, just so the thing would move properly.
I wondered how, if these things are "assembled and tested at the factory", as MicroMark claims, could this lathe have gotten out the door with this issue? Granted it wasn't a major problem, but it would be like going to pick up your brand new car at the dealership, and finding that the door won't open, for example.
In any case, now, when I eventually start turning some longer pieces, and the diameter is more critical (I'd been previously working with short pieces with relatively loose tolerances), I come to find that the lathe has another problem: it apparently has a ridiculously large head stock alignment error, causing it to taper the diameter of the work by about 0.0025" per inch of length.
I knew before I bought the lathe that I'd have to do some initial assembly, adjust gibs, lubricate, change gears for threading, maybe replace brushes in the motor, replace the drive belt periodically, etc.
But what really pisses me off is that it apparently came right from the factory with a fundamental accuracy problem, after ostensibly being "assembled and tested".
I'm finding out that some people seem to be lucky, and happen to get a mini-lathe with pretty good alignment right out-of-the-box, and some unfortunate others, like me, happen to get a POS.
Now, since the head stock doesn't have any adjusment screws; and since, AFAIK, the factory isn't using shims (I haven't heard any reports of anyone finding factory installed alignment shims); and lastly, since, AFAIK MicroMark (or any other vendor for that matter) hasn't made available any kind of alignment procedure...well to me this implies that they're just "slapping them together". Apparently their spec is "whatever it ends up being, that's what it is" kind of a thing.
I guess now I have to decide whether I want to spend time screwing around with it, or whether I should just sell it and try to get something better.
You taper could be from the tailstock being misaligned. Assuming you're using the tailstock for supporting your longer parts and if not, flex in the part could be causing you problems. Jump over to yahoo and look at all the stuff posted in the 7x10 and 7x12 minilathe groups. Lots of info.
I was hoping for something like that, but I put a precision ground, 0.5" diameter by 12" long steel shaft in the chuck and indicated off of that as I moved the carriage and then I rotated the chuck to measure the high and low spots (the so-called "Rollie's Dad's Method"); and it seems really bad to me...about 0.020" over 8 inches...way off.
Yet MicroMark calls it a "high precision" lathe, that's supposedly been "assembled and tested at the factory".
I'm going to contact MicroMark and see what they say about this. I'll see if they'll stand behind their product or whether they'll tell me to get lost.
Did you ask MM for a replacement?
I asked them to kindly align it, giving it some semblance of the "high precision", they advertised. (Being that I live a few hours away from their warehouse, I offered to drive there with it, at my expense and inconvenience).
They refused. (All they did was refer me to Gadgetbuilder's lathe alignment page, LOL! Where's their factory alignment procedure?)
Anyway, I didn't specifically ask for a replacement lathe, as I'm not sure it would be any better. (Unless they convince me otherwise, what you get in the way of head stock alignment seems to be purely a matter of luck).
So now I'm asking that they either refund some of the money I paid for the lathe, or that they take it back and give me a complete refund.
I haven't heard from them yet on that, but I expect the answer will be "NO".
Supposedly they're consulting the factory (Sieg) in China about it...but what's that going to accomplish? I don't think they'll be sending someone from China to make a house call.
What has me so angry is the fact that, when I bought this lathe, the Cummins mini-lathes were selling for $200 cheaper on ebay. Also, I live 5 miles away from a Harbor Freight Store, where I could've bought a mini-lathe for at least $100 to $200 cheaper, in addition to not having to pay $75.00 freight charges. I also live a few hours drive from Grizzly, so I could've gone there and picked up a lathe as well.
Instead, I decided to spend the extra couple hundred dollars, plus freight, in large part because MicroMark's marketing literature and documentation convinced me that, unlike the other lathes out there, I wouldn't have to take the MicroLux lathe all apart and screw around with it to make it half-way decently accurate.
It'd be one thing if the lathe was designed with some kind of adjustment screws, or even if it was delivered with some better documentation, including a factory developed alignment procedure, etc. That all they can do is refer me to a third party web site, that of another hobbyist which just happens to be there, reflects very poorly on them, IMO.
MM was pretty good to me with problems I had with my first lathe. They shipped me a new one and picked up the old one no problems. They also helped me out with my mill when the motor shorted out--gave me a new motor no charge even though it was out of warranty. So I wouldn't bash them until you find out if they give you a new one or not.
That said, MM doesn't advertise any more high-precision than any other SIEG branded lathe vendor does. They offer some xtra features (tru-inch, cam-lock, longer bed, tach, no red goop). I don't think anyone expects the lathe to come custom shimmed to 10ths precision.
Nelson_2008
Putting a .5 bar in the chuck is no way to check the head alignment, to do it right you need to have a precision bar with a 3 morse taper on it, this fits into the head stock, with no chuck on the head, this is the only way to get the head stock aligned to the bed of your machine, the chucks on these machines are not very accrate
The price you pay for a machine like this, is less than what you can buy a good precision chuck for
Mactec54
Good, fast, and cheap. You can always have 2 but never all 3.....
The whole idea behind the widely used "Rollie's Dad's Method" is to be able to measure the head stock alignment cheaply and easily, regardless of the quality of the chuck...because chuck errors are averaged out.
I tried it with two different chucks, both the one that came with the lathe (which seems to have very little runout), and an aftermarket 4" 3 jaw chuck, which does have some runout, and the results were identical. So I have to disagree with you and say that the method apparently works (in fact MicroMark even recommended that method to check the head stock alignment).
Originally Posted by mactec54
Nelson_2008
When you are doing a head alignment,number one,You can not average anything out, it either is, or it is not.
But it seems you know better so don't need any help, The method I said is the only way to get it right, in terms of cheap you can make the bar I'm talking about on your lathe, even with the head out of alignment, & get a perfect part
Mactec54
When I bought the lathe from them, they were referring to it as the "MicroLux 7x14 High-Precision Heavy-Duty Lathe".
According to their narrative description: "Careful workmanship gives you high dimensional accuracy and long life..."
Silly me for taking their statements at face value. I wasn't expecting a $10,000.00 lathe for $600.00, but I don't think it's too much to ask that they spend a few minutes during assembly to do even a half-assed alignment of the head stock.
Oh and BTW, they just sent me an email telling me that because more than 30days have elapsed, they're not going to do anything more than what they've already done, which is nothing. Nice company to deal with.
So, what you're saying is that "Rollie's Dad's Method" doesn't work, and all the people using it don't have a clue as to what they're doing (like this guy), and the fact that I tried it and got the same results using two different chucks is just a freak coincidence?
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