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View Full Version : Taig CNC ready, how ready is that?



JB_in_Fla
03-30-2008, 10:25 PM
I was looking at the xylotec 4-axis kit for $475. It comes with steppers, drive box w/power supply, stepper drivers and parallel port. Am I correct in assuming this simply bolts on to the Taig mill with no further parts required? I viewed the deepgroove video and there were some plastic bits for attachment and I was wondering if I'll have to fabricate anything to get the standard nema 23 motors to attach to the "cnc ready" machine.

Also, there's no mention (other than 20tpi) of the quality of the screws on the Taig CNC mill. Are they quality ballscrews, ACME or worse? What are you guys getting in the way of backlash w/o modification? Are the various retailers (deepgroove, carter tools, etc) selling the same unit or does one seller maybe have better ballscrews, motor, etc?

Thanks!

jalessi
03-30-2008, 11:02 PM
JB,


The Taig mill has chromemoly 1/2"-20 leadscrews on X,Y,& Z however the are not acme.

Ball screws will cost almost as much as the entire Taig mill!

The CNC ready version has the motor couplers included, the are provided by Taig.

The Xylotec 4-axis kit is a bolt on to the CNC ready version of a Taig mill.

What are you going to be using the mill for?

Jeff Alessi
jalessi@aol.com

Stepper Monkey
03-31-2008, 05:49 AM
The CNC-ready Taig is really just that, bolt on motors and go. It's about as straightforward as you can get. Takes about 20 minutes. The plastic tubing bits are part of the motor couplers and they are included along with all the other hardware bits you need like the stepper mounting screws.
All of the basic CNC-ready mill units are the same no matter who you get them from, but if they come with steppers and controllers those vary by seller. The main differences on sellers are the speed at which you get them delivered (whether they actually stock or just drop ship) and the level of support. Nick Carter is famous for after-sale support, Deepgroove is certainly not but can be somewhat cheaper sometimes. Depends on how much you care about such things.
You can count on them pretty consistently getting about .002" backlash right out of the box as shipped. You can spend a bit of time adjusting to get that somewhat better, but still not by a whole lot. If you really need ballscrew accuracy you aren't going to find it with a Taig, and they aren't particularly well suited for being modified to get there. They are what they are - amazingly good deals for the money, very solid, trouble-free, durable and reasonably accurate. More accurate mills are certainly out there, but they do cost a LOT more.

JB_in_Fla
03-31-2008, 07:29 AM
Thanks, that is what I was looking for. I think for most things the 0.002 backlash will be acceptable. Initial parts I would like to make are "hobby" related, small adapters, fittings, r/c parts and such.

Eventually one day I would love to get in on the small IC engine building and I figure I will need more accuracy (and a lathe) then. I noticed the Taig CNC ready is about $200 more than the non-CNC ready version. Does anyone make a CNC ready X3? One that isn't $3k w/o electronics? The Grizzly model is under $1k and I wonder why it cost so much more for their CNC ready version? That's the main reason I'm sticking with a smaller Taig.

jalessi
03-31-2008, 09:03 AM
JB,

CNC Fusion makes a really easy to install bolt on kit for the X3!

http://www.cncfusion.com/smallmill1.html

Take a look you will be impressed.

Jeff Alessi
jalessi@aol.com

JB_in_Fla
03-31-2008, 09:43 AM
So let me get this straight - take the $985 grizzly X3, add the $550 kit w/new ballscrews and throw the $475 xylotex kit on and those parts make the X3 a "bolt on" affair? I'm sure I'd need to talk to xylotex about stronger steppers (z-axis needs to be nema34 from link you posted).

Thanks to you guys, this forum has given me just about enough info to make a purchase that I'll be happy with. The last thing I need is more dead weight in the shop, too many "bad" purchases already!

- Joe

jalessi
03-31-2008, 10:08 AM
JB,

I would hold off on the Xylotex kit.

Take a look at this thread http://tinyurl.com/yrlabp

Gecko is coming out with a new stepper drive that would be alot better!

Then you can just purchase two of these steppers http://tinyurl.com/2627qk
one of these steppers http://tinyurl.com/2gn9ev
and this power supply: KL-350-48 48V/7.3A
110V/230V $59.95
http://www.kelinginc.net/SwitchingPowerSupply.html

The nema 34 is going to strech the limits of the new Gecko drive however you might just purchase a single Gecko 203 drive for your Z axis and use the Gecko CheapDrive for your X Y and A (rotary) axis!

Jeff...

Stepper Monkey
03-31-2008, 10:18 AM
So let me get this straight - take the $985 grizzly X3, add the $550 kit w/new ballscrews and throw the $475 xylotex kit on and those parts make the X3 a "bolt on" affair? I'm sure I'd need to talk to xylotex about stronger steppers (z-axis needs to be nema34 from link you posted).

Thanks to you guys, this forum has given me just about enough info to make a purchase that I'll be happy with. The last thing I need is more dead weight in the shop, too many "bad" purchases already!

- Joe

It both is and isn't quite that simple. It's worth doing, but it isn't really quite a bolt-on affair, it's a bit more complicated than that. Even the mill isn't ready to have anything bolted onto it without some work. While they are very nice mills when set up right, they come pretty rough - often look like very unmotivated people slapped them together pretty fast. Which is kind of exactly the case. Yay, China. Nothing to be scared of if you are good with your hands, but expect some tinkering there.
After that and the kit come the drivers and motors. I would strongly recommend staying away from the Xylotex for that. I recommend them for Sherlines and Taigs and the like, but not this. They are very good, but still not great, for machines that size. They utterly lack the power and most importantly the voltage for a larger machine and Nema 34's it won't do well at all. Some people have used them but it is a false economy spemd the time and money on a mill that large and get a crippling lack of performance trying to save two or three hundred bucks on the drivers and power supply. Go Geckos or something of the like.

In short, a very worthwhile project, and in the end a lot more mill for the money, but it will take a lot more elbow grease and cost a few hundred more than you think to do it right.

tauntdesigns
03-31-2008, 11:43 AM
2 options on the nema34 motor on a cncfusion kit.
I used keling 640oz/in motor on my deluxe kit. If you wire it for series connection it is better suited to the ratings for the 425oz/in nema23's wired parallel. If you do wire them (nema34) series you'd be able to use the new gecko cheap drive set-up.
OR
When ordering a cncfusion kit ask for a Z-axis nema23 motor mount to use 3 nema23 steppers.

Cheers,
Jack

JB_in_Fla
03-31-2008, 05:03 PM
Am I wrong that the CNC Fusion X3 kit will have 0.004" backlash (more than the 'standard' taig from what I hear) with the CNC Fusion "regular" ballscrews? They link to the specs on their site:

http://www.nookindustries.com/pdf/Nook_102.pdf

Right at the top it sais: Lead accuracy: ±0.004"/ft

That may work with the stuff I want to do now but I would like to tackle some IC engines (model type, probably a steam or two as well) and the only reason I'd get the X3 now is to have a machine to grow into and hopefully not out of. I'll probably order by the end of the week one way or the other so all info is appreciated!

- Joe

Stepper Monkey
03-31-2008, 05:47 PM
That's linearity, not backlash. Two different things. Backlash of the screws should be very minimal, though in reality if you are likely still going to get at least .001 or so in the end out of the machine for other reasons than the screw/nut interface itself.
Linearity involves the consistency of the screw pitch, or in other words how accurate the screw pitch is. It isn't always consistent, so they are saying in this case it must be within .004" of travel per foot (or per 60 revs in this case) of max deviation allowable to ship the screw. In other words 60 revs should carry your nut exactly 1 foot, but one screw might be dead on, the next batch could have a travel .002" short of a foot over 60 turns, the next batch .004" longer. They all vary slightly, some more perfect than others, and you can adjust for it if it's there - it is permanent and unchanging. In reality you won't likely notice this number regardless. If you really want to you, you can map the screw and find out. Not a big worry.