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RobZ
09-18-2009, 02:17 PM
Part 1.
Awhile ago I responded to an advertisement from Pulso Motors for a free motor. I soon received a reply asking what motor I wanted. They informed me that while the motor was free I was responsible for the EMS shipping and this amount depended on the size and weight of the motor I asked for. Because I had a need for a 2826/10 size, I asked for this. The people at Pulso, always very pleasant, got back to me with a PayPal address and a request for $20.00. This was done and I soon received a tracking # and was asked to do a small review of the motor soon after I received it. All was set, and I waited while the motor rushed to Canada customs only to run into the glacial speed of the clearance process. Today the wait was over and I got my new motor. As it happens I also have an AXI 2826/10 NIB for another project so I am fortunate that I can make side by side comparisons with these motors while they are both brand new.
I took the Pulso motor to my macro photo set up and began to shoot it from various sides as I had already done with the AXI. I couldn’t shake the feeling that something was very different between the two motors but since the AXI was downstairs in my work room I had not put them side by side to compare yet.
When the AXI was placed beside the Pulso it became obvious what it was I had noticed but had not been able to put into words. The Pulso 2826/10 is exactly 5mm shorter than the AXI2826/20 (as measured using Mitutoyo callipers). This was the case even though it states on the motor label and in the literature that came with the motor, that it is 35mm dia. and 54mm long. The Pulso motor is in fact 49mm.
I looked closer, though, and I noticed that the length of the rotating barrel and the length of the motor where the windings are located have the same length as the AXI. The part that is 5mm shorter is the front, non rotating, housing. This part does not make a difference in the performance of the motor as far as I know. Without disassembling the two motors I can’t say for sure but it looks like Pulso has been able to put the same size magnets and the same size windings, into a smaller package.
If it was shorter than the AXI, was the Pulso lighter too? I measured them both and yes, it was. The AXI 2826 measured at 181 gr (6.38 oz) while the Pulso 2826 measured at 167 gr. (5.89 oz.). So the Pulso motor is 14 gr or ½ oz lighter than the AXI.
As one can see from the photos, the quality of the finish is close to the AXI, and so is the look of the quality of the windings inside. The spaces between the rotating and non rotating parts look even closer on the Pulso than the AXI and this is good. The very subjective “feel” of the motors was that the AXI seems to have an edge on the Pulso in overall quality look and feel.
When I looked at the included radial mount for the Pulso motor, (AXI charge around $20.00 for this) I measured the hole spacing for the prop adapter and found it to be the same as the AXI (15mm dia.) that means that if one wants to use a cooling fan, it will fit. I have the AXI version of one of these and attached it to the Pulso motor to see if it fit, and it does. This means that we have cooling for heli use too, by using an Pulso accessory, available as an extra from their web site.

RobZ
09-18-2009, 02:24 PM
Part 2.
Now here I get a bit picky and the things I say are just personal opinion. The mounting hole spacing on the Pulso is two holes at 25mm dia and two more at 19mm dia. While the AXI has all four holes spaced around a 25mm dia circle. These are 600+ watt motors. There is no place on a 600 watt motor for 19mm hole spacing for mounting screws. Pulso would be better served if it did the same as AXI here and made all four mounting holes on a 25mm dia. circle.
Second the name, Pulso. This name really needs to be changed. What were they thinking? All it makes me think of are 1950’s cheap Sci Fi movies with pulsating monsters, or of living brains on some weird machine with pulsing hoses. I suggest animal names because they are always good. Wolverine or Badger come to mind or better yet Panther because they are black like the motor.
Well this is all very good, but it’s subjective. Soon I will test the two motors head to head with the same props and batteries. For now we will settle for the impression that Pulso motors are very good. When one takes into consideration that the cost to get one will most likely be well under half the price of an AXI, and when we think about the amount of effort the Pulso folks have put into their product launch, I can only come away with the feeling that we are going to see a quality product at a great price being backed by very attentive customer service.
Part 3. The power section, is coming soon.
Rob.

Gohmer
09-18-2009, 02:41 PM
Does it run?

bz1mcr
09-19-2009, 10:31 PM
Good review of the first impressions. Can't wait for some data.

Larry3215
09-19-2009, 11:59 PM
Looking forward to seeing the data as well.

Dont forget the rpm numbers! Too many guys post power numbers only and that doesnt tell the true story.

gramps2161
09-20-2009, 12:11 AM
Quick question on the rpm if you just have a watt meter how can you do the rpm?

dbcisco
09-20-2009, 12:25 AM
"The mounting hole spacing on the Pulso is two holes at 25mm dia and two more at 19mm dia."
This would help in its use in a variety of helicopters where there is no "standard" spacing. Many heli folks replace stock brushed motors which have a variety of mounting holes for everything from 180 to 400 motors. I would say from that POV it is a great feature. It is easier to modify a motor mount for a plane to take two different spacings, if you need four bolts, than to modify a helicopter chassis.

Larry3215
09-20-2009, 01:50 AM
Quick question on the rpm if you just have a watt meter how can you do the rpm?

It depends on which watt meter you have. The Medusa Power Analyzers (my favorite) and Hyperion Emeters both have ports where you can attach electrical phase reading rpm sensors. The Medusa Oracle, the Eagle Tree and some of the other data loggers also have similar accessories.

These phase reading sensors are the most accurate ways to read rpm.

Many of the optical tachs are now digital and are reasonably accurate as long as you're not indoors. Floresent lights especially but also regular light bulbs will mess up the readings of most optical tachs. You can use a flashlight as a light source in a dark room as a work around if all you have is an optical tach.

Ive checked the Hobico optical digital tach and its pretty close from the low end up to about 48,000 rpm. Most of the others drop off in the hi 20,000 rpm range.

The reason you need rpm numbers is to determine if a motor is turning its watts into heat or useful work - spinning the prop.

Ive seen it all to often when someone claims their new motor is so much better than the competition because it draws 600 watts when everyone else is drawing 500 watts on the same packs and prop.

The question is - is that extra 100 watts gong into heat or into rpm? Are you building hair dryers or trying to fly a plane :)

I've also seen the opposite claim - "We only draw 500 watts and it takes you 600 watts to fly the same plane so our motors are more efficient!"

Both claims are just 'Hot air' unless you have rpm numbers to back them up :D

The only good way to truely compare two motors of similar kV and size is to run them both on the same voltage with the exact same prop. Then you note the rpm and the total watts.

The kV and sizes need to be similar so that both motors are running in the same general efficiency range. Its not fair to compare one motor thats over loaded to one thats just idling along.

Once you have the rpm and watt numbers you can compare the rpm^3/watt numbers and the highest number is the most efficient.

The reason for comparing the rpm^3 and not just the straight rpm numbers is that the power required to spin a prop varies as the cube of the rpm.

In other words, if you double the rpm on a given prop it takes 8 times as much power. 2 x 2 x 2 = 8.

If you increase the rpm by 10% it takes 1.1x1.1x1.1 = 1.33 times as much power or 33% more power to turn 10% faster and 800% more power to turn 100% faster.

In other words a 10% difference in rpm number means that there is a 33% difference in power used. So even small differences in rpm are very important to know if you want to compare two different motors.

So, the rpm numbers absolutely are essential or you dont really know anything about how well your setup is performing and you have no idea if one motor/prop combo is better or worse than some other setup.

RobZ
09-20-2009, 01:55 AM
"The mounting hole spacing on the Pulso is two holes at 25mm dia and two more at 19mm dia."
This would help in its use in a variety of helicopters where there is no "standard" spacing. Many heli folks replace stock brushed motors which have a variety of mounting holes for everything from 180 to 400 motors. I would say from that POV it is a great feature. It is easier to modify a motor mount for a plane to take two different spacings, if you need four bolts, than to modify a helicopter chassis.

That's true, but keep in mind the motor shown here is much bigger than a 400. I'm not a heli flyer but would suspect the heli that this would go into would be called 600 size (i.e. Speed 600) and be in the 600 to 700 watt power range
Rob.

Sky Sharkster
09-20-2009, 02:03 AM
Hi Gramps,
Larry is right, a tach is an important tool for measuring motor/prop performance. I've had this one for years. Works great and never a problem. As stated, fluorescent lights will give false readings, but sunlight works great.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=HCAP0401
Ron

Larry3215
09-20-2009, 02:15 AM
Hi Gramps,
Larry is right, a tach is an important tool for measuring motor/prop performance. I've had this one for years. Works great and never a problem. As stated, fluorescent lights will give false readings, but sunlight works great.
http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=HCAP0401
Ron

Yup - thats the tack I was talking about. Its very accurate all across the range and is reasonably priced. It even works reasonably well on edfs up to 48,000 rpm and is still in the ball park up to about 55,000.

gramps2161
09-20-2009, 02:15 AM
Sorry to put your post off topic Robz.
I have a pulso motor also the 2820/10.
I have the the watts up meter which doesn't have the option to check rpm's. I will have to check the meter you gave the link to sky sharkster. Thanks for the lesson in rpm another piece of the puzzle of electric flight good to know this I will have to get one almost ready to test this motor out on a bridi aircruser.

gramps2161
09-20-2009, 02:21 AM
Next paycheck I will get one to go along with the rest of the gadgets that go along with the never ending chain of must have's.:)

RobZ
09-20-2009, 02:33 AM
Sorry to put your post off topic Robz.
I have a pulso motor also the 2820/10.
I have the the watts up meter which doesn't have the option to check rpm's. I will have to check the meter you gave the link to sky sharkster. Thanks for the lesson in rpm another piece of the puzzle of electric flight good to know this I will have to get one almost ready to test this motor out on a bridi aircruser.
Hi Gramps. No problem with me as far as the high jack. If you have a Bridi Aircruser (or a Joe Bridi anything for that matter), are you a re-tread like me? I was out of RC for many years and came back (in 1998). I started in 1969 with a single channel radio called Galloping Ghost. When I returned I went electric only and had to do all of the "old ones" over but e power this time. I have an Aircruser kit and I did put a SunFli 4-20 into the air as well as well as two Bridi/RCM Trainer 40's. I did a Mark's Models BushWacker and have A FlyLine Models Fairchild 22 that I might build. The trouble is I have discovered the joy of building laser cut kits and now the older kits just seem so crude. I love the kits from AerodromeRC and from Radical RC. Beautifully designed and cut.
Rob.
PS
I think I just high jacked my own thread
:red:
OK, I made a motor mount for testing the two motors. I have a tach, and a watt meter (AstroFlight) as well as a 3S and a 4S 2150 batteries. What I don't have is a prop bigger than 12X8. So tomorrow I will run some tests using what I have and at least we will see some info showing relative values between the two motors. I may not get up to the top end of their power but 12X8 on 4S should be interesting. MotoCalc suggests this will have a current draw of just under 45 Amps.

Larry3215
09-20-2009, 03:29 AM
RobZ - that prop should be fine for a comparison. It might be interesting to see both motors with that prop on 3S and on 4S. Might give an indication of where peak efficiency is for both motors - maybe.

Im a little confused about which motors you have - what are the kV numbers on the Axi and the Pulso?

RobZ
09-20-2009, 03:43 AM
RobZ - that prop should be fine for a comparison. It might be interesting to see both motors with that prop on 3S and on 4S. Might give an indication of where peak efficiency is for both motors - maybe.

Im a little confused about which motors you have - what are the kV numbers on the Axi and the Pulso?
Hi Larry.
Both motors are called 2826/10. The AXI has a Kv of 920, and the Pulso has a Kv of 910.
Other Pulso numbers here:
http://www.pulsosystem.com/motor/2826.html
Other AXI number here:
http://www.modelmotors.cz/index.php?page=61&product=2826&serie=10&line=GOLD
I have some 11" props that I will test with too. That will give is at least 3 props and 2 batteries for each motor. That will be 6 numbers for each motr. That will tell us something anyway.
Rob.

RobZ
09-20-2009, 08:26 PM
Part 3.
I did some tests on the AXI 2826/20 Kv920) and the Pulso 2826/20 (Kv 910). I began the tests with two batteries and three props but had to discontinue the use of one of the props and that is a story in itself. The Batteries were; 3S2P 4300 mAh and 4S2P 4300 mAh. The props were; APC electric 12X8, Zinger wood 11X8 and Zinger wood 11X6.
It’s funny how during this kind of test something happens that gives information beyond the test data and this is what happened with this test. I tried to run each motor with each prop and battery and that would have given me five sets of numbers for each motor. I did the AXI first and when I began to do the test on the Pulso I was unable to run the Zinger 11X8 up to full RPM on the 4S pack. It was vibrating like mad and eventually something just shut down and it stopped. All of these props had been balanced and as I recall this prop ran a bit rougher than the other props on the AXI, but it ran OK. The Zinger 11X8 would not run on the Pulso motor. I checked the balance, it’s OK. Hmmm. I took my callipers and measured the blade width, don’t ask me why I thought of that but I did, and found that one blade was .023” wider than the other one. I measured the other props I had and they were all within .002’ so this prop was balanced by weight but the blade surface area was not the same. I’ll mention this again in part 4. when I give my conclusions/opinion. Here’s the stuff:
AXI 2826/10
RPM AMPS VOLTS WATTs
12X8, 4S 7975 59.81 14.10 843
12X8, 3S 6475 37.80 10.75 406
11X6, 4S 9100 44.40 14.55 646
11X6, 3S 7350 28.30 10.80 306

Pulso 2826/10
RPM AMPS VOLTS WATTS
12X8, 4S 7750 54.23 13.75 746
12X8, 3S 6350 35.40 10.36 367
11X6, 4S 9000 39.80 14.10 561
11X6, 3S 7100 26.70 10.70 286
Rob.

RobZ
09-20-2009, 08:27 PM
Part 4.
The numbers seem to show that the Pulso can haul the goods pretty well. I would think it would probably put out as much thrust as the AXI. One observation was that it didn’t get any hotter than the AXI; both of them did get hot though.
The prop thing, the out of balance blade width. If you remember that I noted that the Pulso was lighter and shorter than the AXI and that the difference in length was at the front of the motor where the shaft comes out. This is also were a bearing is housed. One can see from the photos that the bearing in the AXI is much bigger dia. and deeper than the Pulso. When I ran the tests I used the radial mounts that came with the motors. This means there was, as with all radial mounts, more motor hanging out from the mount and more leverage for a wacky prop to put force on the bearings. I think that the AXI is a more ridged frame and has stronger bearings and this is why it ran the wacky prop better than the Pulso. I think that the AXI is a tougher built motor.
Ok, is this a fatal flaw? No. The Pulso runs well and it cost a heck of a lot less than the AXI. I will certainly fly this motor and probably buy more of them. The bottom line in my opinion is that you get what you pay for. Is the Pulso (gawd I hope they change that name) as good as the AXI? No. Is the Pulso worth what I expect them to sell for? If they are going to retail this motor for around half of the price of an AXI, a very big yes.
Rob.

dbcisco
09-20-2009, 08:44 PM
Thanks for a very scientific analysis.
Much appreciated.
I also hope they change their name.

max-nix
09-23-2009, 01:06 AM
Using Scorpion Calc V 3.30

SII 3020-890

http://www.scorpionsystem.com/downloads/

http://www.innov8tivedesigns.com/product_info.php?cPath=21_25_80&products_id=522

http://innov8tivedesigns.com/Scorpion/Scorpion%20SII-3020-890%20Specs.htm

file:///K:/Scorpion_Calc_v330.zip

::o

ron_van_sommeren
09-23-2009, 12:13 PM
Most recent Scorpion_Calc version always available in first post of this Scorpion_Calc announcements and help thread. Subscribe for news about software updates.
http://www.rcgroups.com/forums/showthread.php?t=736782

Vriendelijke groeten ;) Ron

ron_van_sommeren
09-23-2009, 12:17 PM
... The spaces between the rotating and non rotating parts look even closer on the Pulso than the AXI and this is good ...Size of the stator-magnet airgap is a design trade-off. Smaller airgap gives more magnetic flux, resulting in more torque, but losses in the stator-iron go up.

Vriendelijke groeten ;) Ron

RobZ
09-23-2009, 01:48 PM
Size of the stator-magnet airgap is a design trade-off. Smaller airgap gives more magnetic flux, resulting in more torque, but losses in the stator-iron go up.

Vriendelijke groeten ;) Ron
Sorry, I should have been more specific. I was looking at this gap when I wrote it.
Rob.
http://www.wattflyer.com/forums/attachment.php?attachmentid=109411&stc=1&thumb=1&d=1253280239http://www.wattflyer.com/forums/attachment.php?attachmentid=109410&stc=1&thumb=1&d=1253280239

RobZ
09-30-2009, 09:15 PM
Here are the prices. Pulso 2826/XX = $63.30us, AXI 2826/XX = 109.00us
http://www.pulsosystem.com/motor/2826.html (http://www.pulsosystem.com/motor/2826.html)
http://www.icare-rc.com/modelmotors.htm (http://www.icare-rc.com/modelmotors.htm)
Of course shipping remains the big question. It was $20.00 from China for the Pulso EMS) and from ICARE (for the AXI) it will be about half that cost, both for a one week delivery. So “at the door prices” are:
Pulso = $83.30
AXI = $119.00
At these prices I would take the AXI every time. Better motor and a N.American dealer to back it up. I'm afraid that the Pulso would need to be cheaper to change my purchasing decision.;)
Rob.

av8djc
10-01-2009, 02:34 PM
Here are the prices. Pulso 2826/XX = $63.30us, AXI 2826/XX = 109.00us
http://www.pulsosystem.com/motor/2826.html (http://www.pulsosystem.com/motor/2826.html)
http://www.icare-rc.com/modelmotors.htm (http://www.icare-rc.com/modelmotors.htm)
Of course shipping remains the big question. It was $20.00 from China for the Pulso EMS) and from ICARE (for the AXI) it will be about half that cost, both for a one week delivery. So “at the door prices” are:
Pulso = $83.30
AXI = $119.00
At these prices I would take the AXI every time. Better motor and a N.American dealer to back it up. I'm afraid that the Pulso would need to be cheaper to change my purchasing decision.;)
Rob.


Rob
When I was looking on the Pulso website the prices were inclusive of shipping to the USA.

RobZ
10-01-2009, 08:07 PM
Rob
When I was looking on the Pulso website the prices were inclusive of shipping to the USA.
Sorry. I can't find that on the web site. Could you please post a link to the page they state free shipping?
Rob.

C130 Load
10-01-2009, 09:15 PM
Sorry. I can't find that on the web site. Could you please post a link to the page they state free shipping?
Rob.

They posted it here:
http://www.wattflyer.com/forums/showpost.php?p=647372&postcount=153

av8djc
10-02-2009, 01:52 AM
They posted it here:
http://www.wattflyer.com/forums/showpost.php?p=647372&postcount=153

Robz

I saw it less than a week ago really shown as free shipping on the website just after the price. It's not there now. I think that we have a start up company here with perhaps a great value high quality product but are teething on the marketing side ;-)

newjak
10-02-2009, 02:06 AM
I saw the "free shipping " notice on their website too. As you stated its gone now. Hopefully whatever problems they are having over there get resolved soon.

spad
10-02-2009, 05:20 AM
Robz

I saw it less than a week ago really shown as free shipping on the website just after the price. It's not there now. I think that we have a start up company here with perhaps a great value high quality product but are teething on the marketing side ;-)


I've been using Pulso ESC's for 3 years.

burtgreen
10-04-2009, 09:11 PM
I wish I could get one to test myself, emails don't seem to get to them.

nick_cool
10-09-2009, 12:09 AM
Hi, do you know if AXI in the extra 5mm is putting an extra ball bearin as they do in the bigger motors?

It makes a great difference in the robustnes, in the life span, and in the cost...

Nick

PS I got one pulso for free too, here there are some measurements:

http://www.rcgroups.com/forums/showthread.php?t=1097572&page=4

RobZ
10-09-2009, 02:51 AM
I don't know if there is an extra bearing in there but if you compare photo #2 and #3 in the first post you can see that the AXI bearing has much larger diameter. It's hard to measure without taking the motor apart but they are approximately: Pulso = 14mm diameter, AXI = 16.5mm diameter. It might be deeper too or it might be two bearing in there, but again I can't tell without taking them apart.
Rob.

nick_cool
10-09-2009, 04:31 PM
Confirmed, AXI uses 3 ball bearings, that’s why it is heavier and longer.


A friend that disassembled a 500g and 180g AXI motors told me so.


Nick

MontoRC
11-19-2009, 01:27 AM
They're not offering any more free shipping from Pulso directly. I am however offering it for a limited time on Pulso motors at my website.

RobZ
11-19-2009, 01:52 AM
They're not offering any more free shipping from Pulso directly. I am however offering it for a limited time on Pulso motors at my website.
Pulso was giving free shipping to Canada. Are you going to do this too?
Rob.

MontoRC
11-19-2009, 02:12 AM
RobZ, Thanks for asking, but right now we're just not setup for shipping to Canada. Its something I'll be looking into soon. Sorry about that. If its something we stock send me a message from the contact page. Maybe I can work something out for you.
JIM

gtxkid
03-01-2012, 02:09 AM
So after all this time how does the 3 bearing of the AXI compare to Pulso.
Did pulso step it up or what.
Now with the Multi rotor guys are using lot of AXI's because of what is needed.
Vibration free for Arial photo exc.