Are these the same: Pk296ae-sg7.2 (metric) = Pk296a2a-sg7.2 (inch)?

[gixi]

Hello Gerald, hello everybody,
After several sleepless nights I come to a conclusion with my future project.
I’m not reinventing the wheel because the MM design is more than enough for my business (thank you again Gerald).
But buying the “kitchen project” it can become a problem for me .
Oriental Motors US don’t deliver to Europe :mad: so I have to buy from Germany and when I was looking for
PK296A2A-SG7.2 motor on OM-Germany I couldn’t find it.
The only one close to this model is PK296AE-SG7.2 2-phase stepping motors (PK-Series) (90 mm).
http://www.oriental-motor.co.uk/uk/sites/produkt_4.php?ida=3&idser=69&idpr=1240&sgid=72
Is it the one?
Please advise…
Thank you,
Marius

[domino11]

Marius,
The specifications do look identical. I would probably call oriental motor in your area and get them to verify the cross reference to the US part number just to make sure.

Maybe Mike R has some experience with the EU part numbers? He probably has a bunch in his test setup somewhere. :)

[Gerald D]

That looks like a fully metric (millimeter) version of the same motor. It should work.

[Richards]

The PK296AE-SG7.2 appears to be the 8-lead PK296-F4.5 motor with a gearbox attached. That would be the motor that I would choose if I could get Oriental Motor to add a gearbox to it.

The current requirements are the same, the inductance is the same. In fact, all of the specs seem to be the same.

I would wire it half-coil using a power supply of about 35VDC (the maximum voltage using 32 X SQRT(1.5mH) = 39V). Normally a 35VDC power supply is the closest standard power supply that you'll find. Set the current limit resistors to allow the Gecko G203v stepper driver to deliver 3 amps (36K, 1/4W) and you'll have a very nice motor/driver/power supply combination.

The reason that I would wire it half-coil is that the gear box (assuming that the gear box is the same that they furnish with the PK296A2A-SGxx motors) limits the torque to a level lower than a half-coil wired motor can produce. So, by wiring it half-coil, you'll have the maximum torque available.

[gixi]

Finally someone from Germany redirect me to a Romanian company.
I speak with the Romanian company and Wednesday I’ll pay them a visit to give all the details. The prices are almost the same with US catalogue.
But the technical tell me at the phone that this motor doesn’t have enough torque.
I explain to him to see the youtube MM but he didn’t believe.
I don’t take for granted his opinion and I’m just buying.
The Gecko and PMDX didn’t answer to my emails. Should I call them? I hope they deliver in Europe…

Thank you for the moment.:)
Marius

[Richards]

The PK296A2A-SG7.2 motor w/gearbox has been proven to be a good motor/gearbox for the MM. Another version (PK296A1A-SG3.6) with even less torque (due to its requirement for a higher voltage power supply) and its 3.6:1 gearbox, instead of the 7.2:1 gearbox has been used for years with the Shopbot PRT machines.

With the proper power supply and proper tool pathing, the PK296A2A-SG7.2 motor is a good match. That means that the PK296AE-SG7.2 would also be an excellent match for the MM.

Just be aware that you have to use practical values when cutting. I normally make multiple passes when cutting 3/4-inch MDF to get the best possible cut without needing to sand. I could cut 3/4-inch MDF in one pass, but then the extra hand sanding would take more time than letting my machine take an extra pass. I'm lazy, so I let the machine do the work for me.

[jan stransky]

Does anybody have a information about backlash of this gearbox ? It does not have to be the information from the catalog. Information from real MM setup sould be even better.

As Richards wrotte a 3 AMP at 35V should be enought to drive PK296AE-SG7.2 what dou you think about using G540.

[Gerald D]

Welcome Jan from Slovakia

Backlash in the gearhead of the Oriental Motor PK296A2A-SG7.2 (http://www.mechmate.com/forums/showthread.php?t=887)

Will the new Gecko G540 drive a Mechmate? Yes, it already does. (http://www.mechmate.com/forums/showthread.php?t=628)

[jan stransky]

I think backlash up 2 degrees is too much. I asked MS-MOTORS.COM for the information about backlash in their gearheads and answer was 1.2 degrees. I took a look at WITTENSTEIN Alphira gearhead and they have a 1:5(10) planetay gearbox with backlash lower than 20 arcmin what should be 0.3 degree for 137 EUR. Gearbox torque up to 16 Nm. What do ypu think about this option. Gerald could you ask some people which have OM + gearbox installed on MM about their experiences with MM backlash ? BTW PK296AE-SG7.2 does cost 209 EUR + 19% VAT in Slovakia. :eek:
I think a 1:10 Alphira gearhead + high torque NEMA 23 + G540 could be cosiderable option. What do you think ?

[domino11]

Jan,
Check that backlash thread, people seem to be seeing a lot less than 2 degrees of backlash from the oriental motor gearboxes. Not sure what the official backlash number from Oriental is right now

Backlash in the gearhead of a new Oriental Motor PK296A2A-SG7.2 was measured today at 0.43 degrees. On a machine with 30 tooth DP20 pinions, that will be about 0.005" (For the metric people with 36 tooth module 1 pinions, that will be 0.13mm).

Note that the gearbox is SG7.2.......that is Standard Gearbox (with SH gears) 7.2 ratio.

[gixi]

Ok. The local representative from OM confirm that PK296AE-SG7.2 is similar with PK296A2A-SG7.2. Tomorow I'll place the order (two weeks for delivery).
At the end of the week I'll buy the steel.
Wish me luck !!!

Marius

[Gerald D]

I think backlash up 2 degrees is too much.

Jan, maybe we have a language understanding problem. I measured that gearbox at 0.43 degrees. Where do you get a figure of 2 degrees?

. . . . . What do you think ?

I think you can believe me. The recommendations here are based on what hundreds of people are happy with.

[Gerald D]

Marius, thank you for finding the PK296AE-SG7.2 motor and confirming it is similar to PK296A2A-SG7.2. I have already modified the motor recommendation thread. :)

Can you give us the name of your local Oriental Motor dealer?

[Gerald D]

Jan

Thanks for the mention of Alphira. It looks worthwhile to investigate . . . .

Datenblatt alphira 060 (http://www.shop.alphagetriebe.de/medias/f1Mz1wNNoOCNBcfsKQPGhe-30.pdf?mime=application/pdf&realname=Datenblatt_alphira060_080813_d.pdf) (PDF-Datei) (Data sheet)
Betriebsanleitung (http://www.shop.alphagetriebe.de/medias/WnTocV8VWWreLqC6QIiNia-30.pdf?mime=application/pdf&realname=Betriebsanleitung_CP_DE.pdf) (PDF-Datei) (Installation instructions)
Motoranbauanleitung (http://www.shop.alphagetriebe.de/medias/n9fdEXtFbXreLqC6QIiNia-30.pdf?mime=application/pdf&realname=Motoranbauleitung_CP_B5_02.pdf) (PDF-Datei) (Motor mounting instructions)

Price US$ 176 in Germany

Lots of English (and American/Canadian) info on Alphira around the world:
http://www.motioncontrol.com/products/index.cfm/alphira--a-New-Addition-to-the-Alpha-Family-

[gixi]

Marius, thank you for finding the PK296AE-SG7.2 motor and confirming it is similar to PK296A2A-SG7.2. I have already modified the motor recommendation thread. :)

Can you give us the name of your local Oriental Motor dealer?

Hi Gerald,
Today I was overloaded by problems and I didn't visit the dealer.
The name of the company is "ADF Industries SRL" and the web site is http://www.adf.ro.

Thank you,
Marius

[jan stransky]

Fyi