[woodworker2]

Question, I have a 4' x 4' router I just finished building, and for $650 I can get 4 individual new 32bit DSP DM556 digital drivers, breakout board, 48V power supplies, housing case, fans, everything to build a complete unit. Or for $670 I can get the Gecko G540, housing case, fans, 48V power supply, as with the other choice, everything I need to get up and going. Also in the listed prices are 4 Nema 23 445 oz/in 3.5A low inductance stepper motors. Question to this community, if this was your money which would you buy and why?

Thanks in advance for your opinions.

[peteeng]

Hi WW2 - 1) You can build cheaper control systems if you shop hard for all the parts and hone down the specs to the minimum. Then you have to put a lot of time into assembling them, checking them twice and making sure you don't let any smoke out. If you let smoke out then you have done the budget and it becomes costly. It's easy to make smoke with these things!! 2) by getting an all in one solution the chances of letting the smoke out is small. You save time in wiring and getting the right wires and you use much less space in the build. I have a gecko 540 and it's done very well. I have abused it and it has survived. I have also built component level systems (let the smoke out twice) takes a long time to sort.

So if you don't have time or are not electronics savvy get the all in one solution. If you have a week or three to figure out all the connections and you like doing that, then get separate components. I've done both and to my mind I'd go with the one box approach. But the G540 is limited to 3,5A and this means you can't put big motors on it. Not even large N23 or N24's. And I think they say if you run 4 motors then its 3A max on each? I'd look at Buildbotics 6A per axis and many bells and whistles (this covers all N23 and N24's and some N34's). Comes with the wires and external controller. A good thing. I'm planning my next build B#4 (I've built 3 machines so far) and that's what I'm going to use. Peter

https://buildbotics.com $450USD plus need to buy a power source, I think this is well ahead of the other solutions.

G540 pluses - it works very well, technical support very good
G540 minuses - soldering the small connections is a pain, you will have to use limiting resistors as your motors are at full axis capacity and may trip the system like mine did initially.

Buildbotics get so many more features than above, more capacity, S curve motion, hand controller, don't need a dedicated computer for the machine, Plus plus plus....

[ger21]

I'd get the DM556's, but I'd also find higher current, lower inductance motors. A 5 amp motor of similar size should outperform a 3.5amp motor by a good margin.

But, if it were me, I'd spend another hundred, and move up to drives tha can handle 7 amps and 80V, and go with 6 amp Nema 34's running on 60V. This should give you close to 50% better performance, for about $250 more.

[woodworker2]

Thanks for the advise. Is there a big difference between a digital DSP driver and a digital bipolar chopping driver?

[woodworker2]

Thanks for the input Pete. I am confident I can handle the driver wiring, the breakout boards are some what limited on wiring info. I have already figured layout and power wiring for both options. I will look into the Gecko 4 axis power limit. Its a good point. I will check out buildbotics too

[peteeng]

Hi WW2 - Seems they have not updated their manual since I had the issues, so it maybe fixed. I had 4A motors and they kept telling me that I did not have to put limiting resistors in (I did it at 3A). Plus they acknowledged that the hardware was a bit sensitive when 4 motors were connected and tended to trip early. They sent instructions on how to modify the motorboard which was to remove a component in the circuit board. Once I did that and added the resistors it has been flawless ever since (2 years with hard use).Cheers Peter

[jaru-eri]

What is your experience with dm556? Is it a good alternative to Gecko? I´m thinking about buying these drivers and need to know how they perform.

[peteeng]

Hi Jaru - I have not used DM556 but looking at its specs its only rated at 24V I'd go much higher then that. gecko runs at 36V... The box has 20-50V DC on it but it may self limit to 24V ??? Then on another diagram it says 24-70V so who knows?? Same as amps one place it says 5.6A then another it says 4.5A so get a full spec sheet from the supplier before you jump! Peter I still think Buildbotics is streets ahead...