Having worked with lathes in the past (both metal and wood), and having bought, used and then sold the TAIG lathe to my former workplace (they have lovely CNC turning machines, but they can’t work any stock less than 1″. I made the case, they agreed, and it paid for itself quite well) I realized that while a lathe is very important, it can only do round things (imagine that)!
In actuality, the TAIG was a little undersized for the usages I had in mind, and the former company wouldn’t hear of anything more expensive (no matter the rationale). A case could be made for a mini-mill as well (there were no manual mills, only the Mazak and Haas Vertical Machining Centres), but I knew they wouldn’t go for it.
As such, since I’d already decided I wanted (needed? it’s so vague) one, I started research into various units.
That research showed the following paths:
Micro-Mills (Printed Circuit and Jewelry suitable units; TAIG, Sherline)
– I’d decided these were too small for my likely uses; first rule of machine tools: get as BIG a working area as you can imagine needing realistically. These were accurate, but not big on envelope.
– Both of these machines are NOT new, have loyal followings, and plenty of experience. I had no complaints about the TAIG lathe, and the parts can be interchanged. As a bonus, they could be purchased in “turnkey” CNC configurations!
– When looking at work envelopes, for the price, I decided I wanted more envelope and power.
Mini-Mills (Re-branded Chinese units of varied quality) (I say re-branded due to their being only two manufacturers at the time, and several machines of differing name)
– Here’s where I learned the term “Snowflake Mill” also known as “no two alike”. I saw them represented all over the planet; Europe, Australia, USA.
US Re-Worked Mini Mills (ones made to a US manufacturer’s specifications- Re-worked Chinese machines, or ones built to US company specifications
– At the time of my research, one company making these, Little Machine Shop (rebranded SEIG SX2, SX1, SX3 built to their specifications)
Mini-Mills (European Brands)
– Reported excellent (example: the Proxxon brand) but really not economical to obtain in Canada.
Macro Mills (IH Clones, the X/SX 3 series, RF-45 and clones, Refurbished Bridgeport machines)
– These are what I was being steered towards by professional machinists, but the costs were a bit high for my starter position ($3000 and up), they were very heavy/took up a lot of room.
Entry Level Manual/CNC-Ready/CNC Equipped (LMS 3501, Tormach 770/1100, Novakon Torus/Pulsar, etc.)
– Fantastic machines, ones a professional would use, or a serious hobbiest. However, prices, mass, work envelope, and power requirements were all equally impressive.
– Don’t misunderstand; Rigidity, and therefore weight, are critical the larger the workpieces to be handled/amount of material removed/speed of operations. You want a bigger work area? That costs, in money, material and weight.
I was looking for a mill of moderate size, at the upper limit of one man portability, reasonable work area, reasonable accuracy (hobbyest), well supported/understood and potentially upgrade-able to CNC.
With those in mind, plus much research from those in the know, I decided on the Little Machine Shop LMS 3960 Mini-Mill. This variant comes with a solid column, which increases the rigidity, prevents it from being knocked out of tram when an oops occurs, and most machine operations can be done without the tilting column.
This image is what it looked like after the addition of an Air Spring modification; as of this writing (19th Apr 2014), they sell this included as the 3990 model. The Air Spring modification solves some of the head nod issue, give some extra travel, and carries the head weight MUCH better than the torsional spring normally mounted.
As a humorous aside, not long after I purchased it, I could have paid for the mill with a job I was offered, if only the head would tilt (would save the person from purchasing a trunnion table)…
Here’s an example of a tilting model (the LMS 3900, I believe) with a CNC kit on it