View Full Version : is anyone running the 88 free delivery chinese usb bob's

23-07-2013, 02:03 PM
3 Axis CNC USB Card Mach3 200KHz Breakout Board Interface | eBay (http://www.ebay.co.uk/itm/281108442161?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649#ht_1359wt_922)

just bought one of these.

firstly do I need anything else?????

23-07-2013, 08:22 PM
Nobby can I just say your making the classic mistake new folks make.? Your buying blind with no idea what your buying and that's a recipe for blowing money and frustratement with the result being either a dead machine or under performing machine or worse still a buggy erratic hair pulling bitch of machine.!!

I don't have any experience of that particular board but having lots of experience using most of the other motion control cards available for Mach3 I very much doubt this can do what it claims.!! Some of the things it claims it can do are not easily implemented and often require Artsofts involvement with making the plug-in to control it and I very much doubt they have had involvement in this.!!

For someone with experience then it would be worth checking out at this price but for someone with no experience then I'd strongly advise not to bother and stick with the traditional proven parallel port or spend that bit extra and buy a proven motion control card like the Smooth stepper etc.

IMO your in for a world of pain and uncertainty using this card, the list of troubles it could and probably will throw at you is huge and very much doubt the backup is there to help resolve any issues.!! . . . . Result being you'll waste weeks or months messing around and getting frustrated and then still rip it off and throw in cupboard.!! . . . . Trust me on this I have a cupboard full of " look's promising" and many many wasted hours of life I'll never see again.!! (and I'm supposed to know better and with experience . :whistle:)

Now regards " Do I need anything else????" then besides the obvious drives, motors and PSU the minimum you'll want is an E-stop switch. Limits and homes switches etc are optional but recommended, you'll also want shielded cable for these.

Other than that you should be set to go just to try the motors etc but with that said.!!. . . . . What I strongly recommend you do is look at designing and building the control box so it's E-stop system is hardware driven and not just relaying on software to stop the machine in an emergency condition like what you will probably do at first. (Most new users do.!!)
It's not difficult to build a hardware driven E-stop system but I'm not going to get into it know but recommend you research and look/ask about it.

23-07-2013, 10:12 PM
When you want to know what others think about the product (ie that have bought it), use an ebay feedback filter ...

Feedback Selector - Search Results (http://www.feedbackselector.com/feedsearch.php?seller=goodlucksell&itemName=Breakout+Board+Interface)

only two people have left feedback for 200khz breakout boards from that seller (albeit 4 axis ones), but both seem content with their purchase.

John S
23-07-2013, 10:47 PM
Sieg are now fitting this board as standard, admittedly the 4 axis one.

I have some here we are also fitted to retrofit machines.

So far these haven't given any problems. The plug in works fine, as you say Artsoft have had no involvement with the plug in. Perhaps that why it works give the progress with Mach 4 ? :mushroom:

23-07-2013, 11:03 PM
thanks for the heads up
-I had woes of buying it in error

do they come with a wiring diagram, or is it self explanitary
i don't need spindle control,
will have limit on each end of each axis?
will it take that same amount of time to come as my mount?
4 weeks!!!
i only ordered the motor on 21st sunday, twas here this morning!!

23-07-2013, 11:13 PM
So far these haven't given any problems.

Luckily for Nobby that's good to hear John.!

BUT. . How much of it has been tested or pushed.?

The Russian Purelogic motion control card worked fine with run of the mill operation but when pushed with probing etc and custom screens it soon fell down.!! . . .Has you know this is when the selling companies metal gets tested and how they go about fixing the problems sorts the men from the boys.!! . . . . In this case Pure logic soon sorted the issues and good company to deal with.

Has for Mach4 then I'm saying nothing.:eagerness:

23-07-2013, 11:55 PM
i do have a
standard - if you can call it that? parallel bob
plus a pci parrallel port, in the event it does go mammary glands up, but thought I'd like to try it usb first, well for the 88 quid anyways
if i have problems I can switch in the latter. or even have the bob in a different box altogether.

what was foxing me was the power supply to the parallel bob is 36 volts, but on the usb, its usb powered and 5volts
= don't like electrics too much.
its a shame they simply don't make a bob card to fit in a pci slot.

p.s. can i cut 20mm foam pvc plastic with that 710 watt motor on full chat in a single pass, and that said, what bits do i now buy
twin flute up or down?
single flute?

24-07-2013, 01:22 AM
what was foxing me was the power supply to the parallel bob is 36 volts, but on the usb, its usb powered and 5volts
= don't like electrics too much.
its a shame they simply don't make a bob card to fit in a pci slot.

Thats often were USB falls down it's flaky at providing a smooth consistent 5V and why if possible you should always run the board from external 5v supply if it has that option.? . . I'm always weary of boards that rely on USB to provide power.!!

Most decent BOB's provide range of voltage they work at so you can use the same supply has the drives or control PSU. Often they need minimum 12V for powering things like relays or Opto isolaters on the board.

31-07-2013, 12:47 AM
hello, well it came today, took a week from chine which isn't too bad.

anyways its a Mach3 Usb Motion Card (AKZ250)

set up is quite simple really following the on-line instructions here

Leafboy77 - Home (http://leafboy77.com/index.php/en/)

the board has leafboy77 on it, there is nothing in the box pertaining to this, I only stumbled upon the logo - near the usb port by chance wondering why there wasn't a note in the box, anyways really quite easy to set up.
I now have cnc, which is most good!!! usb to boot!!


what you won't find on-line is a clean novice/idiots guide to connecting it to the drives - what you need is a picture
the dip switch settings there = 3,2 amps and 32 micro steps
i dunno what that means but copied it

here is the size comparison pic