I am interested in extending the Z axis travel on my Taig CNC mill. Also I would like to know if Z axis bracing would improve the mills precision.
I think the Z axis travel could be easily extended by making three longer parts. These parts are shown in the attached diagram.
The longer parts would replace the Z-Axis 3" Steel Box Way (200-42), the Z-Axis 1 1/4" Steel Box Way (200-43) and the Z-Axis Leadscrew (LH) (200-25A). The longer parts should bolt right in. Does anyone know what kind of steel Taig uses in the 3" Steel Box Way and the 1 1/4" Steel Box Way or what kind of steel would be appropriate? Could I use the Taig X-Axis Leadscrew (RH) 2018 (200-26) for 9.5” of Z travel? Or even the X-Axis Leadscrew (RH) 2019 (200-26A) for 12” of Z travel? How much extension could be accomplished in this manner without causing problems?
Another modification would be replacing the Z-Axis Leadscrew with a ballscrew, this would require additional parts and modifications. Would a ballscrew on the Z axis and Acme screws on the other axes cause problems?
The Taig mill and the Sieg X2 Mini Mill have a similar method of attaching the Z column to the base. Several people working with the X2 have developed braces as described here: http://www.hossmachine.info/Shop_Info.html#x2%20column . Would a brace for the Taig column be a good idea? Has anyone developed a brace system for the Taig?
I JUST had the exact same idea, and just logged on, and just went to the Taig section to see if anyone had done this before.
And this was the top post. That's creepy!
I think you have a great idea. In fact, thanks to both looking at my mill, and your picture, I see now that I could attempt to unbolt,
and rebolt the head way assembly up at least one or two notches higher for a bit more clearance now. I had to square it up with my
dial indicator anyway. I was going to do this today, actually, and so I'll attempt it, and see how well it works.
My reason for wanting higher clearance? Simple- I have a sherline rotary table and 4 jaw chuck on my x ways, and a jacobs chuck
in the z axis at top hight, and the part I'm drilling is just too high for a normal length bit by like 1/2". I haven't really made much with
my machine after a year now, learning how to setup everything and having the time and money for stock, and then I ran into this.
I really, REALLY could use another 2-3 inches of clearance on Z for drills, since I can't find short drill bit packages.
I also just realized I have a precision ground plate 12" long, 4" wide, 1/2" thick, that would only need chopped down and lightly lapped
to make an entirely new Z axis ways!
I'll let you know how my progress goes today when I'm done.
EDIT: Crap, forgot I don't yet have a dial indicator stand. I don't think I can do this today. I will still try unbolting and see what happens to
rigidity for you. It is only since I haven't finally trammed everything in, except perpendicularity of the Z to the X (I'm still on basic techniques)
that I know no real damage can be done here- it was going to be dialed in anyway, as I don't plan on making anything until I fully tram every
part in true with a dial indicator.
I have a good, rebuilt Starrett 0.0005" last word, works great. Perhaps I can rig something up to work as a stand today.
Last edited by Odin; 09-18-2010 at 02:16 PM.
Reason: Forgot I don't have the right tool yet
but it might add some rigidity. It wouldn't hurt, in any case.
Rebuilding the Z axis box ways would be something of a project, but not a huge deal. If I were going through all that, I'd consider welding some more square steel tube onto the top of the column, to keep it solidly supported.
A ball screw on the Z axis would be problematic, though. Even if you got something as precise as the stock screws and made enough clearance for the nut, you'd need to counterweight it somehow to keep the spindle from plummeting every time you killed the power. Ball screws are nice for conserving motor power, but they have a tendency to back-drive themselves, which can be disconcerting if you're not expecting it.
A ballscrew conversion is probably not the cheapest and easiest solution. I am thinking of going with the Taig X-Axis Leadscrew (RH) 2018 (200-26) for 9.5” of Z travel. But the Leadscrew nut for the Y Axis is a (LH) Nut and the X Axis is a (RH) Nut. Does this mean I can't use it or I can use it and just reverse the stepper rotation in Mach3 or will additional modifications be required?
To stiffen the extension I was thinking of making the base of the replacement for the original 3" Steel Box Way (200-42) 0.75" thicker to give me 0.75" more Y travel. This would also require 0.75" spacers on the Y axis extrusion. What do you think of this idea?
Your last post is confusing. Your thread is about the Z axis and all of a sudden you are talking about the Y axis nut...
Clearly the X axis screw won't work in the Z axis nut. I think the X axis nut will fit in the Z axis though. Then you just have to reverse your direction setting in Mach. The LH thread on the Y and Z are a legacy from the manual mill.
Thanks for pointing out my error. The first paragraph should have read:
A ballscrew conversion is probably not the cheapest and easiest solution. I am thinking of going with the Taig X-Axis Leadscrew (RH) 2018 (200-26) for 9.5” of Z travel. But the Leadscrew nut for the Z Axis is a (LH) Nut and the X Axis is a (RH) Nut. Does this mean I can't use it or I can use it and just reverse the stepper rotation in Mach3 or will additional modifications be required?
You wrote: "Clearly the X axis screw won't work in the Z axis nut. I think the X axis nut will fit in the Z axis though."
I can't figure out what this means in terms of Taig parts. I have attached the manual mill parts diagram. Could you identify the parts you think I would need to get?
Another option is to purchase a Acme Leadscrew (RH) of the proper diameter and thread. Does anyone know what these are and where I could purchase a Leadscrew (RH) in the length I want?
Use the 200-23 or 200-23A nut. The A is the cnc version with adjustable backlash. Before ordering anything though check that the round bosses on the X and Z are the same diameter. I am pretty sure they are.