Will 203V Gecko drive control a Boss 3 stepper motor

[jbrant]

I am looking into new controls for a bridgeport BOSS 3 CNC Machine and im having a hard time finding useful specs for this machine online. Would 203V gecko drives be able to effectvely power the big stepper motors or is there a more suitable driver?

[HimyKabibble]

Since nobody has answered.... I know nothing about a Boss3, but my impression is the BP steppers are high-voltage - like 160V. Geckos are limited to 80V max, and 7A max per phase. So, you'd have to replace the power supply with a lower voltage one (70V or so, to leave some headroom), and you may lose some top-end speed capability. I do recall reading of people who've done this, and seem to recall they got reasonable results. I would think an archive search should turn up some threads about this.

Regards,
Ray L.

[austin.mn]

I have a boss 3 machine and am currently running it off of some compumotor drives that I got off ebay. The motors do not microstep! When the drives are set to micro stepping they jump a little, not really changing position until the next full step. Then they leap!

So keep that in mind. Otherwise I don't see that they won't work... They just won't work real well. I am going to spend some tax return money this spring (if there is any.....) and get a new set of triple stack 34's to replace the beehives that are on there now.

If you have the money, don't bother with the old 42's you have, just replace them before the frustration sets in. I really wish that I had swapped mine early on, but with needing to run the machine, and all the tooling that needs to be purchased just to make it usable... well you get the picture.

Hope that helps.

[jhowelb]

I have a RongFu mill I converted to cnc with compumotor drives and steppers. one of the drives took a dump and because I can't find a replacement I used a 203v with a 40v power supply.

It's on the z axis and does not need much speed and it works fine.

Motor runs much cooler than the others.

[cholder]

I see this is an old post, but I have reworked 3 Older Stepper Type Bridgport machines. I used the 201 units. The original Bridgeport setup was for the current to be set at 8 amps. I did some test with the older motors with the Geckos set to the maximum 7 amps and did not find very much difference. The problem I have found with the older motors is the resolution is only good to half steps. I don't recall the what the voltage should be but I don't think it is over 55 volts DC. The old Bridgeports used a satuable reactor for each motor to limit the current at low speeds. I removed all of the DC transformer stuff and replaced it with a single phase power supply for the steppers and added an invertor to make the machine run on single or three phase power.

[MARKG]

I am using 203V's for all three axis. I used Roland Freistad's design from Home Shop Machinist for the controller, 58 volts if I recall correctly.

Speeds are really quite good now, much faster than in the vid clip on the link below, will post and updated vid clip soon.

YouTube- BRIDGEPORT PROGRESS REPORT

[MARKG]

Right. As promised, a series of youtube vidclips showing the resuscitation of the machine sourced on Kijiji for 1000$. Gecko 203V's running on 60V DC with Mach. I am max'd out at about 90 ipm. As my old race engine builder used to say..."....good enough for who it's for..." :-)

As austin.mn noted above, I think an upgrade to newer (1200 oz in Keling NEMA 34's?) is in order at some point.

YouTube - BRIDGEPORT CNC PROGRESS REPORT 1
YouTube - BRIDGEPORT CNC PROGRESS REPORT 2 - CONVERSION TO VFD & POLYV BELT DRIVE
YouTube - Bridgeport CNC Progress Report 3 - BUTTONED UP AND CUTTING!
YouTube - BRIDGEPORT CNC PROGRESS REPORT 4 - FLOOD COOLING

[gotfdirtball]

Nice job! Thanks for the vids. I'm in the middle of the same converion. Do you mind sharing the source for your power supply?

[austin.mn]

That machine was way too clean to have been in use for 8 months....

Nice Job! One of these days I will have to give mine a bath.

[MARKG]

austin.mn, thanks, eight months of hobby use only mind you. The sheet alum chip catcher / enclosure really does help contain the coolant!

gotfdirtball , the power supply is something I picked up off the shelf from my local electronics emporium. Here's the link;

Home - Addison Electronique Ltd.