Mel,
Thanks and good to hear your report on the SF-266SA. I first began looking for EN22 motors back in 2017 because of your postings on the MR forums and your web site. But could never find them. Finally when I found the SF-266SA in the repower/regear Groupio I figured it was a winner based on what those guys had done with it. It looks like you have proved that. By the way, I bought 6 in two orders and each of those came in 12 days - fast! Most electronic stuff from eBay China for me has been over a month of shipping. Good luck with your next ”266” adventure. Also, I don’t know if I had said this - I removed and discarded the “266” plastic end cap and cut the shafts down to 10mm. Thanks again.
Steve - Arlington, TX
I'd think with your power setup plus an accurate measurement of RPM, yooou could calculate a close enough torque. You have the elements needed, just have to get them all in agreeable units. Even just measuring the stall torque plus the no-load RPM should give you what you need, on a permag motor there is a linear relationship from one endpoint to the next. Torque at any other RPM should then be easily calculated.
A skewed wound motor, all else identical, should theoretically have better loow speed torque. And better starting characteristics. I suppose this can be made up for somewhat by a good drive system, goood BEMF, PWM with torque coompensation, etc. I'm going to predict that you will see a greater difference with these straight wound motors between the MRC decoder and the TCS BEMF ones, as the better drive of the TCS will make up for the lack of skew winding.
Are they really 6 pole. not 5 or 7? There are 6 commutator segments? Even poles is rather odd.
Edit: Can't find a data sheet, but found an eBay listing with one disassembled - wow, indeed a 6 pole motor. Odd. I may have 2 od them - in my car. Seems they are commonly used for folding the side mirrors. Cheap enough, too.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I wonder which one is in my car - not about to take my mirrors apart to find out though.
Max torque should be when stalled, at rated voltage and current. Between there, 0 RPM, and max RPM with 0 torque load on the shadt, again at rated voltage, is s strictly linear relationship, so the torque at any intermediate shaft RPM should be easily extrapolated. Thoough this will be the torque at the rated voooltage, not torque at whatever RPM it turns when fed say 6 volts.
The sixth pole may make up for the lag of a skewed armature - might be a sweet spot between a 5 pole skew wound armature and a 7 pole. I've seen it mentioned in the past when it was complained that the 7 pole motoor in questin wasn't skew wound that with enough poles, it doesn;t really matter, the skew helps the most on 3 and 5 pole armatures. I sort of remember from old magazines back in the day of open frame motors, there were 5 and 7 pole versions, and I kind of remember seeing someone advertise a 15 motor.
Mel and Randy: Since you guys might do testing of this motor when using DCC, there are a couple of things I read about the Mabuchi SF-266SA when it comes to their use with DCC. You may want to look into the motor's back electromotive force (BEMF) and its internal capacitors (it has two tiny SMD components acting like capacitors). I am not a DCC user but I found that this motor is perfect for my DC HO repower projects. The "RepowerRegear Groups-io" site where I first learned about this motor last spring has lots of postings about this motor and those topics. Apparently, some years back members were testing some other motors with capacitors and found that there were problems using those other motor with some DCC decoders but the problems were eliminated when the capacitors were eliminated. The BEMF stuff I ran across was over my head but they get into that quite a bit. I never understood the lingo when reading about these topics. Anyway some members have taken the capacitors out of "266" circuit and it appears easy to do from the photos and explanations that are there. That Groupio site is full of info. If you go to the group and use its search function with "SF-266SA BMF" and "SF-266SA capacitors" you will find lots of postings and that stuff can better say anything I can post here.
Steve
Well, if those capacitors aren't easily accessible, that is a bummer. Yes, they do interfere, not only with the BEMF, but also with the high frequency PWM drive from the decoder. They would be the equivalent of the external capacitors on many Bachmann locos.
Looking again at the ebay listing that shows one disassembled, I can see the caps on the brush cap. And it looks like the motor was pretty much destroyed to pull it apart like that. If that's the case, this motor is a non-starter.
Randy,
Having studied that RepowerRegear Group about the SF-266SA quite a bit and popped off and discarded that plastic end cap on the motors I am using, I have studied the crimping of the metal end cap to the case, I have to agree with what members of the group said even though I have not done it as I'm all DC - it is easy to get to those capacitors and cut the connections and it was easy to reassemble and when installed in locos ran fine. Heck, at just over $2 a motor (currently), you could toss a few if you did mess up compaired to the cost of other motors. Now, there is a NO capcitor version of that Mabuchi, the SF-266SH, which has lower rpm than the SF-266SA. Depending on the loco, a few group members were looking at it.
Hmm. I searched some of the posts, and most sound a bit complicated - maybe not in practice, but when written down it doesn;t make it sound too easy to get them apart. One mentions removing the knurlign from the output shaft so it fits through the front bearing - frankly that's already sounding like a bit too much work just to save some money. My biggest concern is getting those brushed back in place without bending them, even if there is no need to fully remove the armature (which seems odd - I do think the person that posted that wanted to take it completely apart to drill mounting holes without drilling into the motor and also allowing a way to clean out any chips.).
Considering I have very few locos at this point which I would even consider needing to remotor - maybe my brass RS-3, but it already has a decent can motor, and the Mantua 0-6-0, which is a newer version with some sort of can motor, not an open frame motor - I might just spend more money and get the Canon motor. Most of my stuff is less than 20 years old and has decent motors, so unless one absolutely fails, I see no pressing need to swap them out. They all run nice and slow with a good decoder, and quiet. Any issues are possibly in the fore and aft slop in the worm gears causing bndng on grades, which is realtively easy to fix with thrust washers.
The "removing the knurling" only applies if you are pulling the armature out of the case in order to get the shaft thru the output end's bearing. This is done if you are drilling holes in the forward end of the case for attach points. When cutting the lead on capacitors, you only need the metal end cap off. I read one modeler used chisel end blade(s) in Xaxto and a couple of fine tip screw drivers to separate edge crimps. When reassembling, you need to spread the brushes to fit over the armature commutator.
Well I guess I missed the source for this motor! The Canon motors are hard to come by after Motorman passed.
can some one lead me to a place to buy?
thanks
Woodone,
SF-266SA source is China via eBay. There appears to be no USA source like Motorman. Assumption is this motor, made for automotive outside mirrors, had a big overrun. Thus far, they are very cheap and are free shipping. Orders have arrived in less than 2 weeks.
Thanks Steve.
That will help.
Over about the last year I have installed these Mabuchi SF-266SA motors in 25 Hobbytown drives ,I am very happy about performance results . The Hobbytown drives are all flywhell drive unit tha ran very well with the supplied DC 70 motors . With these Mabuchi motors they run even better at slow speed and throughout the speed range.
In the last few months I have used these Mabuchi motors on ten brass diesel drives in Alco models and a Red Ball diesel I am very pleased with the results it has turned some shelf queens into fine running units. I did two Alco Models S2 switchers with one motor they now run very well compared to the old motors.
All the others are setups that had double ended motors so I mounted two motors since these are single ended, These all run much better. All the brass diesels have some form of KMT drives with these new motors there is a great improvement.I run DC only . I did remover the white nylon end caps which shorten the motor a bit . I soldered power wires to the tabs at the end of the motor, The motors were all mounted on a bed of silicone adhesive.
Ron High