Mach2 consideration questions

[jevs]

I am trying to figure out what control to use for My Machine. It is a 1978 Pratt & Whitney Tapemate C. It is a small bed mill (20" x 15" movement I think) with a 7 tool changer. It was marketed more as a speedy drill and tap machine I believe. It has Fanuc 0-2000M DC servo motors and uses 2000 pulse encoders (not resolvers luckily). I was thinking of using a BTR setup, but have since found out the Fanuc 5 is limited to moving only 2 axis at a time. Plus for not much more than a BTR I can just get rid of all the fanuc controls. I was planning to use my drivers which require -/+10 V input. So far the top 2 choices I have found are Mach2 (with a rutex step direction converter) or go with a setup from Camsoft. Mach2 is much cheeper and I would love to use it, but is there any feedback or is it just open loop? If there is no closed loop operation, how good would this be on my machine? I want to do some nice 3D work at some point. Can Mach2 handle the tool changer? Is it worth the 10X in cost to go with camsoft? Or, is there something better out there for me? I am all for doing this as cheep as possible, but I don't want to end up with something that is a dissapointment when I start making parts.

[turmite]

jevs,

I use Mach2 and love it, but I don't know how to answer your question. Yes mach2 has inputs for encoders but I don't know for sure if it closes the loop or not. I would suggest a direct email to Art at artofcnc. He will be able to help you out. There may be others here that know this answer....just not me!

Mike

[Barker806]

I think you should look into Mach2 and the LARGE Servo Drives from Rutex. The old Drives are nice but you can NOT get new ones! But if you use the Rutex drives you can fix them on your own! As for Mach2 I like it! Camsoft is OKAY but if you are going to do it your self Mach2 is much better...


Hope that helps

Brian

[jevs]

What about the no feedback to the controller issue? The controller never knows the true location of the mechanicals? It only knows where it told the machine to go. If there is any binding or whatever wouldn't it get off? I am all for the cheeper route I just need to know the negatives that go along with it. Also, will mach 2 work with my tool changer? That is another big thing to consider. Camsoft says they can do a tool changer, but I am not sure about Mach2?

[turmite]

http://groups.yahoo.com/group/mach1m...guid=169082179

Go here and you will find more help than you can imagine. the Mach2 will do ATC as well as give you a lathe controller, a plasma controller and free upgrades. You can't get better than Mach2 for the money and in a very shot time it will be giving many of the big controllers a run for their money.

You can download a free demo that allows you 1000 lines of code but will only run at 25k hz, which is the speed I run my system at anyway. Digitizing........included no charge....dxf.....and some other options for creating gcode. Brian Barker has been working hard to make Mach2 conversational as well as convential. In case you can't detect my excitement about this product let me just spell it out...I won't own anything else.

In addition to Mach2 being so good, Art is working in conjunction with Mariss Fremanis of Gecko in having the software ready when Gecko comes out with a new "box" that will have tons of i/o's, and will run stepper motors up at servo speeds. I can only imagine what it will do for a servo system.

Support is second to none.

Mike

[jevs]

By ATC, I assume that means Automatic Tool Changer? Also, what about the fact that there is no feedback to the controller? This is not really a hobby size machine. I also need it to be accurate.

[jevs]

From what I read Mach2 cannot operate a tool changer unless you write your own Visual Basic program or something.

[Barker806]

Originally Posted by jevs From what I read Mach2 cannot operate a tool changer unless you write your own Visual Basic program or something.

Yea, But the VB is part of Mach2. You don't need any other software if that is what you are thinking... I have examples of code that I have done to run a tool changer But it is not going to be the same as the one you need.

If you like I can post an example of what the code looks like.

Also feel free to mail me off list if you would like to know more.
Brian

[jevs]

So how important is a closed loop system verses an open loop system on a larger machine that you want some good precision out of? What are the downsides of going with mach2 to save all that money?

[Barker806]

Originally Posted by jevs What are the downsides of going with mach2 to save all that money?

Th down side is that if it is not wired right you could have a problem with the Axis stalling an the machine would not know it... the new drives fron Rutex have setable following error and you can tie that to an input into Mach2. As for the down side ... the feedhold isn't fast... It will run code faster than a New Fanuc! It will not let you have the feed override down to zero....

All and all it is GREAT

Brian

[HillBilly]

Jevs,

I have used both softwares you are considering. Coding a tool changer for either one is possible and requires you to learn VB for Mach or CamSoft logic. The CamSoft system based on the Galil card has alot of bells a whistles. The Galil card is a powerful motion controller but was originally made for industrial automation. Where this comes evident is when you try to servo orient your spindle and bring Z to 0 together (Like the original controller did for a tool change.). You should be allright with controller logic controlling
your tool changer (If I am correct In assuming your tool changer is a turret type like most TapeMates.). I would suggest a seperate PLC for a magazine and two sided arm tool changer. The reason I say this is because when performing spindle orient and Z0
for the tool change it is nice to start the magazine indexing the proper tool. The same would apply for indexing the magazine for tool unload, once the correct tool is in the spindle the CNC can start machining and the PLC can deal with putting the tool in the right pocket (Like the original controller did.). I see no way to do this with either softwares coding.

My personel opinion would be go with Mach and step/dir servos. Dollar to feature there is no comparison. I think the screen designer to Mach is superior to CamSoft and also the way the software functions inside of windows studder free. I also do not like CamSoft's upgrade policy (Its the software that keeps costing.).

Darek

[jevs]

So your saying there is no real advantage to haveing the direct feedback? What if I want to machine something manually just by jogging the machine around? Would I not have a DRO on the screen with the Mach 2 setup? I did want to keep the mill so I could use it "manually" when I just need to modify a part or make something quick. I do alot of stuff where I need dto work stuff on the fly and the only mill I have now is a mini mill from grizzly which I wanted to get rid of and use this for everything. I know its not as good as handles for manual, but it should work fine if you can jog it around with buttons and use the DRO on the screen.