Best 4 Axis Setup for Taig Lets hear opinions

[gunlocators]

OK I have a Taig 2019CR-ER CNC Ready Mill on the way and want to go the 4 axis route. I need a controller and steppers. Here is my question. Hands down I do want to eliminate any isuues such missed steps ect. This is for intricate inlays for pool cues so I need a really good setup. so here is my question.

So what would be the
Best servos?
What servo oz is hands down going to be the best?

Best Controller?

Pendant Controller?

Best software?

Also any other tips that will help ensure the machine is reliable as possible

This is for a 4 axis setup using a sherline rotary 4th axis

[Stepper Monkey]

You are going the right way with the Sherline, it can't be beat for the price or anywhere near it. It has a 72:1 ratio or thereabouts if I remember correctly, so a very small, fast motor is required.
A 72:1 torque multiplication means even the smallest motor will do, but it needs to be stepping very quickly to get any decent rotation speeds at the chuck, and while big motors may have high initial torque, it falls off quickly as RPM's rise.
A small motor with a flat torque curve is perfect. I use a little 110 oz/in or so PacSci single stack. It has more than enough juice through that kind of gear reduction to spin a moose, and an inductance of only about 1 mh - not a misprint, its not 8 or 18 or 34 or some other number we are used to seeing, but just 1. If you don't know much about the math on how the motors work in practice, lets keep it simple and just say it keeps roughly the same torque it has at speed as it had at rest (holding torque). It will still be turning out 80-90 oz/in at speeds where similar 280 or 495 oz motors are putting out only 30 or >14 oz respectively - the speeds a stepper attached to this kind of reduction will need to spin at.

I don't know what to say about software, I don't do the same kind of stuff you do, but I would say before spending a ton of money on a fancy pendant you should try a simple one first.
I personally love the simple hack of using a simple Xbox controller as a pendant. You can get them used at a game store for like 10 bucks and the Mach3 patch to use it is free off of Artsofts site. Or just use a generic PS2 style PC game controller. Plently of programmable buttons there. I prefer mine over my "proper" pendant actually.

[gunlocators]

OK With that said what exact steppers and controllers would you go with brand wise. Wheres the best place to get them.
Thanks In Advance

[Fixittt]

if your wanting stepper drives, then gecko would be the way to go in the hobby sector. Their are industrial stepper drivers available as well. My best advise is to contact support from the www.geckodrives.com page and explain what you want to do, what you have. Then get some advise from them as per what drives, steppers and power supply to get to meet your needs.

As for control software, I would first say mach3. then EMC2

[Adamj12b]

I would say go with the new Gecko Drive G540. 4 axis driver all ready to go with built in breakout board. It uses the new g250 stepper motor drives. I just bought 6 of the 251's which are the same the 250, but with headers instead of pins. They are incredible. The G540 will handle 4 3.5A motors all in a nice little enclosure. I also think that Keling makes some stepper motors that are a good match for these drivers. -Adam

[rcsimpson]

Talk to LocoCNC
http://www.lococnc.com/catalog/produ...products_id=92
This is the setup I got with the 4th Axis to boot. Very sweet!!!

[Kelinginc]

OK With that said what exact steppers and controllers would you go with brand wise. Wheres the best place to get them.
Thanks In Advance

Check here
Stepper motor package
http://www.kelinginc.net/CNCNEMA23Package.html
DC Servo Package
http://www.kelinginc.net/CNC23ServoMotorPackage.html
CNC controller
http://www.kelinginc.net/ControlSystem.html

[JoeDawg]

First of all welcome to the world of benchtop CNC milling and gl with your custom cue maiking (got a custom viking myself). I recently bought the same mill (w/o the xtra x-axis length) and configured my own motors, drivers, etc. Stepper Monkey is right in saying that you need a 4th axis stepper w/ a lower holding torque. Now for your axis motors you dont need alot of torque for woodcutting, but a 4 axis package with 4 identical steppers is not what your going to want. My 282 kelings (@36 volts) rapid at 20 IPM and I don't slow down much for wood. That could increase with a higher voltage driver/pwr supply combination (i.e. geckos @50v). Steppers won't miss unless you tell them to move faster than they can, whether they be maxed out hitting a axis limit (buy limit switches!). To determine your max speed just rapid a known distance then go back to where you started much slower, it you don't get back to the same place, then your missing steps. After a little experimentation this shouldn't be an issue, and servos probably aren't necessary. The gecko 540 seems like a great deal and would be plenty of juice, 3x axis motors (200-300 oz), a 4th axis motor (~100 oz), and a power supply that can keep everything fed (close to driver max voltage and amperage = or greater than that of motor requirements) and you should be good to go. Not an expert, but that's my opinion...

[gunlocators]

First of all welcome to the world of benchtop CNC milling and gl with your custom cue maiking (got a custom viking myself). I recently bought the same mill (w/o the xtra x-axis length) and configured my own motors, drivers, etc. Stepper Monkey is right in saying that you need a 4th axis stepper w/ a lower holding torque. Now for your axis motors you dont need alot of torque for woodcutting, but a 4 axis package with 4 identical steppers is not what your going to want. My 282 kelings (@36 volts) rapid at 20 IPM and I don't slow down much for wood. That could increase with a higher voltage driver/pwr supply combination (i.e. geckos @50v). Steppers won't miss unless you tell them to move faster than they can, whether they be maxed out hitting a axis limit (buy limit switches!). To determine your max speed just rapid a known distance then go back to where you started much slower, it you don't get back to the same place, then your missing steps. After a little experimentation this shouldn't be an issue, and servos probably aren't necessary. The gecko 540 seems like a great deal and would be plenty of juice, 3x axis motors (200-300 oz), a 4th axis motor (~100 oz), and a power supply that can keep everything fed (close to driver max voltage and amperage = or greater than that of motor requirements) and you should be good to go. Not an expert, but that's my opinion...

Ok I am a CNC Idiot so bear with me. What would happen if I went with 400+oz servos for 3 axis and 100oz for the 4th is there and ill effects with that combo in case I was to want to work with aluminum. Also is the gekco drive the best route and how reliable is it...

[Stepper Monkey]

I would definitely concur with Joe, for wood you need moderate but consistent torque through all speed ranges, not a lot of power low down. Also, I for a Taig-sized machine and for what you are doing going with servos would just be extra hassle and a giant waste of money for no real performance gain. Steppers will do you more than fine for this.

100-150/oz motor for the rotary, and 175-250/oz or so motors for X and Y. Z could use 250-300/oz or so, but not at the cost of too high an inductance (the mh rating on the motors), as you need to keep up the speed.

Gecko drivers are well supported and ahve a reputation for being absolutely bulletproof. A Gecko 540 with a 48v supply will do you very, very well, and any Nema 23 steppers that cover at least the oz/in range above with the least amount of inductance you can get will be fine.

Look to buy motors that the current draw is matched to near the Geckos output, with an inductance number hopefully around or under 4 mh and maybe allow double that for the Z. This may mean running some or all of your motors bipolar parallel, you can mix and match to get the right combo of power, and of motors running both parallel and serial, on the same controller. They don't all have to be wired up the same way or be the same strength.

If you want some direct suggestions I can do some digging for exact motors that might work for you, But follow the above guidelines and you can't go far wrong, there is a lot of range there that works.

[TOTALLYRC]

I have the same mill and I can vouch for the fact that you don't want to go with the 425's when using the stock 20tpi screws. It will limit your rapids especially if you use the Xylotex combo with these motors. Max voltage of 35 including back emf which to be safe probably is 30v coming out of the dc bus into the drives.

I have also just bought the G251's at the special price. I got 6 4 for the Taig and 2 for a project to named later.

The best bang for your buck right now seems to be the g540.
This will give you 4 axis of control plus a built in BOB and the ability to drive a vfd without buying anything else. You will want the convenience of variable speed from the computer, especially if you do wood and aluminum on the same mill. I mean that people have been changing belts and gears manually for a century or more but I have gotten real attached to turning a knob to change speeds on my manual bridgeport instead of changing belt positions, same with my manual lathe.

While I have not used the Kelling Items suggested above, I have bought a motor from them in the past and I was treated well. Fair price and quick shipping.
The numbers for his G540 package come real close to perfect as far as numbers go. When I say perfect I mean the ability to get the absolute max from the G540. I have yet to see a motor that is rated exactly for 3.5 amps and 50v, which are the limits for the G540 and G250/251's. But this will change I am sure.
You really can't go wrong if you spend a few more dollars now instead of saying I will upgrade later. It always cost a lot more in frustration and time then to spend the money now. Ask me how I know.

While My Taig has and is making money, I just get so frustrated when doing a long part with a hole on each end. The rapid travers times to go from one end of the table and then back are actually longer the the maching time for the 2 holes. Thas is why I am upgrading to the g251's. I would have gone with the G540 but I already have a breakout board installed plus the introductory price was just too god to pass up.

A thing to remember is that the 425 oz rating is holding torque while stationary, and because a larger motor has a higher inductance the torque will fall faster as the speeds rise than with a smaller low inductance motor.
With a 20tpi screw it will really show up as you try to go anywhere fast.
For cutting aluminum you will not need any more torque.
As you slow the feed rate to cut aluminum as opposed to wood,the steppers actually generate more torque. The other thing is there isn't a whole bunch of power in the stock spindle motor. I mean you cant drive a 3/8" end mill at a 3/8" depth of cut so how much servo torque do you really need. In defense of the Taig it wasn't designed to do that but when used within its design parameters it is a wonderful machine to use.

If I remember correctly on the Xylotex web site it even recomends that you go with the 282's as opposed to the 425's on a Taig with the 20tpi screw.

It will of course not hurt anything to use different motors on each axis as long as you set the current limiting for each motor. You can even use a different tpi for each axis and it will be ok. It is one of the great features of the software packages that you input the steps per inch and it all gets figured out in the computer.

I also have the sherline 4th axis and It came with a much smaller motor as part of the package. I have yet to try it but it feels like a quality unit and a lot of people use it.

As for the reliability of the Gecko's. All I can say is that they have been working for almost three years on my router and they have not given me a problem even once. When I had a question I shot off an email to them and Mariss replied the next day and we went back and forth with a few more questions. Very rare in this day and age to get that kind of contact from an owner of a company.
It is the main reason that I am using Gecko's on all my other projects when they fit the bill. The only reason I am not using them on my BTC-1 is the dc bus voltage is over the max for any gecko product and it already came with usable drives.

[gunlocators]

Ok I just ordered a Gecko 540 Now I just need to find a source for a 48v supply and Nail down the exact steppers to buy. I will eventually get all this CNC stuff