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Hello
I was wondering if anyone has ever used a Taig mini mill or similar table top mill. I need to make some small parts for a pickup assembly, and they would be much easier to make with a 4th axis. As the cheapest 4th axis for my centroid controller starts at around 6,000 I was thinking of buying one of these smaller machines. You can get the taig with a 4th axis for around 2grand. I have shopped around to get the parts made, and I will probably spend around 2 grand to get a couple of hundred of each made. So why outsource when you can possibly by another tool. I actually went out to the taig facility here in chandler, az and was impressed by the product. I also went by maxnc, and there little mills just seemed a little too "flexible" I have never seen a sherline in person. Anyway, if anyone has any insight or firsthand experience with any small mills, I would appreciate your input.
thanks,
Evan

ps I will be maching 6061 aluminum and tellurium copper

I have some experience with small table top mills. I have a sherline cnc 4 axis machine that I am just about to put on ebay. I have been using the sherline mills and lathes for years.
I use it mostly for engraving and making parts for my RC cars, and model engines. I works perfect on aluminum. It works with steel, and I even know some guys how routinely cut titanium with it, but you have to decrease depth of cut and feed rate. I have not cut much copper with mine, but it was no problem at all. I have cut cast iron to cut the epitrocoid shape for the housing of a model wankel rotary engine.

Some of the parts/accessories are interchangeble between the taig,max and sherline. Littlemachineshop.com has some good stuff for those small machines.
the most important thing is your work envelope. These little machines have a very small work area. aluminum and copper should not be a problem for any of the machines you mentioned.

Let me know if you have any specific questions, I would be happy to answer what I can.

Devin

What are the parts and what kind of machine is your Centroid hooked up to? If it's full sized then your three axis is going to be able to beat a tiny 4 axis machine handily on time with good fixturing, so I'd check out the cost of setting up a good fixture VS the cost of a new tool.

_________________
Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

My mill is an Atrump knee mill. The parts, one is a .3125 diameter disk with a notch in it, the other a small v shaped piece. I wanted to have the small v shape cast, but I can't find anyone who will cast it in copper. I have looked at a horizontal/vertical rotary table, that may work. I just got a quote back from the centroid rep, and a dc 4th axis is a hair under 8000 by the time you send the control in for the software upgrade, and buy the 4th axis and a chuck(this is for a 3.9") Buying a small mill would also allow for making cavity covers, etc and not have to pull the primary fixtures off the big mill. I have 14.5" of y travel and 32 of x, and the knee mill table gets crowded pretty quick. I got the mill (which was in excellent shape) from a plastics company for dirt cheap (4950.00) that was downsizing. Its one of the best deals I have ever found (perhaps it helps offset some of the other cnc stuff I started with that didn't work out so well). The other plus of a table top mill is being able to make an enclosure for it to keep chips and coolant from going everywhere. I am considering all options, but trying to be smart with my money and time.
Evan

Evan
I used a Maxnc10 for a number of years before upgrading to a Techno CNC router. It is truly amazing what can be done with these tiny machines keeping in mind the small work envelope. Speed was not that much of an issue as I would normally go off and do something else while it was running. I did retrofit a servo drive system later on to get reliability over the steppers which were terribly underpowered. Made a few other little mods such as extending the X axis travel. Even then I had to do fretboard inlays by indexing the workpiece on the table once to cover the 16" or so distance on the X.
The little machines are a good choice for someone wanting to wet their feet in CNC without spending a ton of money and taking up a lot of space.
Nelson

What are you guys using for CAM? I haven't looked too closely, but 4 axis Cam programs seem to cost a fortune.

Bob

Bob, I used 3 axis CAM for the little bit of 4 axis work I've done. I set the Y axis on the 4th axis centerline then switched the Y axis output to the 4th axis servo and encoder. Then it's a matter of scaling the Y to the diameter and circumference of the area being machined. Certainly not as easy as 4 axis CAM but lots cheaper.
Nelson

Thanks Nelson. Guys at the DIY CNC forum I belong to do the same, I just wanted to make sure I wasn't missing out on a cheap CAM program.

Bob