Alternative Motors for BL-CTRL 1.2?

[FlyEYE]

Looks like I need to replace a motor or 2 and I have what seems to be discontinued, the MK2832-35. Are there other motors suitable for the BL-CTRL 1.2 (besides MK or Robbes)? All the ones I can find seem to exceed the 10A max draw of the MK or Robbe's. I'd be running of 4S.

 

[Bartman]

i'm sure RTRyder will see this and respond but you might also want to send a message to DennyR as he's done a good amount of motor/prop testing and will probably have an answer for you.
you could also call these guys and ask them what the equivalent Pulso motor is

http://montorc.com

let us know if they answer the phone there.

 

[FlyEYE]

I've already used the contact page at montorc a couple weeks ago , no response (so they are email shy as well?), also rctimer.com no response (but that was yesterday).
Replacing all motors with with the Roxxy 2827-35s isn't too attractive $wise and I don't want to be bitten by an uncommon motor again. I could just buy two of the 2827-35s as they seem to have the same specs (as the 2832) except a slight difference in weight and shaft height and have them run opposite each other.

 

[RTRyder]

I've already used the contact page at montorc a couple weeks ago , no response (so they are email shy as well?), also rctimer.com no response (but that was yesterday).
Replacing all motors with with the Roxxy 2827-35s isn't too attractive $wise and I don't want to be bitten by an uncommon motor again. I could just buy two of the 2827-35s as they seem to have the same specs (as the 2832) except a slight difference in weight and shaft height and have them run opposite each other.

It appears that motor is still available from Germany https://www.mikrocontroller.com/index.php?main_page=product_info&products_id=443&language=en

If you want to look into Pulso email Jim at Monto directly @ info@montorc.com, that has always worked for me. That said, there are no good alternatives that can be purchased at the moment, both Pulso and AXI compatible motors are out of stock everywhere. Even so Pulso motors would be roughly the same price as the MK Roxxy 2827-35, and anything AXI would be a LOT more expensive. I had a set of Pulso motors purchased that I was going to use on my soon to be built MK but as I noted in another thread the USPS lost the shipment, now they can't be replaced until new stock arrives and that probably won't be until the end of the month at the earliest.

Personally I would not run unmatched motors, the weight and balance won't be the same and you might see a lot more vibration.

Ken

 

[FlyEYE]

My concern is that it won't be available at the German site for long either, so I'll be in the same boat a little later. Might be the easiest solution for now however.
Is there anywhere that "refurbishes" motors?

 

[RTRyder]

My concern is that it won't be available at the German site for long either, so I'll be in the same boat a little later. Might be the easiest solution for now however.
Is there anywhere that "refurbishes" motors?

One, buy a spare or two to go along with whatever you need for replacements, likely a similar cost to just buying a complete new set assuming its a quad.

Two, refurbish them yourself, source the correct size bearings from Boca bearings and replace as necessary to keep the current ones working. Short of burning up the windings there really isn't much else that can go wrong unless you crash and do physical damage to the bell or shaft. Shafts can be be easily replaced as well though you might have to source them for another motor and modify (shorten) to fit.

Three, start a motor replacement fund and begin researching suitable replacements.

Really aren't any other options, I don't know of anyplace that does refurb on these motors and if there were the cost would likely be as much if not more than the replacement cost by the time you factor in labor, parts, and shipping back and forth...

Ken

 

[FlyEYE]

Thanks, leaning towards getting a couple new ones, and figuring out how to refirb now.
It's a hex so I was trying not to replace all 6 .

 

[Bartman]

glad you got some help. i thought you were going for a complete replacement of the motors.
with RTRyder's help I got my XA quad's motors apart after driving it into the ground and getting them muddied up. They come apart very easily.
Bart

 

[Ryan Thomas]

FYI

The BL 1.2 is 10A(160w)continuous and 20A(320w) Peak on 4S, so you can go for other motors,

I plan to use AVRoto's with my okto, I will just monitor the amps and limit my full throttle, however the BL.1,2 can handle 320w peak for a few seconds, which is only slightly less the AVRoto's Peak so it should be fine for normal flying.

 

[FlyEYE]

Ryan, you mean the AVRoto 2814-11?
I ended up replacing the bearings and now they're great. After paying attention to how many amps the hexa draws I'm never near max so less worried finding the exact match. The AVRoto looks good.

 

[Ryan Thomas]

So how are the AVRoto in comparison with the roxxy's?

They should use less amps for the same thrust, or at least that's my theory

 

[Bartman]

Ryan, you mean the AVRoto 2814-11?
I ended up replacing the bearings and now they're great. After paying attention to how many amps the hexa draws I'm never near max so less worried finding the exact match. The AVRoto looks good.

I thought the Avroto motors were a replacement for the bigger MK motors, but you guys are using them in place of the smaller Roxxy's?

 

[Ryan Thomas]

Yes that's my plan,

On an okto using BL 1,2 you have in theory a total of 80A continuous and 160A peak, with a 4kg okto I am hovering using 35A with roxxy's, so half of what the system can handle.

My theory is bigger motors, bigger blades, a little extra weight. I will probably end up using around 25A-30A, The avroto is similar to the pulso & mk3635, which If you look the amps per grams of thrust on the chart on the mk.de website, A 4kg okto will use 24A to hover.

So why change to the BL 2.0 when you will be drawing less the 5A per controller and the BL 1,2 can do 10A continuous!

View attachment 366



The only thing I will change is max throttle, because the peak amps of the motors is over 20A and will fry the BL 1,2 ESC at full throttle.

 

[Bartman]

If the same props are being used then the copter is going to fly at the same rpm regardless. In theory the bigger motors should handle the heat generated better than the smaller roxxy's, no?
Bart

 

[Ryan Thomas]

I think to sum it up bigger motors with bigger blades will give you the same thrust with less amps, or more thrust at the same amps

For example the
- A MK3638 at 3.5A is producing 450g of thrust with EPP10X4.7
- A Roxxy at 3.5A is producing 440g of thrust with EPP10X4.7

so you right bart BUT!!!
The MK3638 at 3.5A it's producing 580g of thrust with APC14X4.7, that's 130g more thrust, less extra for the motor around 50g. So on an okto you will get 640g more thrust for the same amps! That's a 550D DSLR

 

[connexxion]

If the same props are being used then the copter is going to fly at the same rpm regardless. In theory the bigger motors should handle the heat generated better than the smaller roxxy's, no?
Bart

Bigger motors are heavier so will need more rpm to stay in the air with the same size prop.

I tend to use no more motor than I will need to fly.

 

[Bartman]

i see my name but i don't remember being a part of this conversation!

i agree though that the extra weight of the larger motors must be carried along with the rest of the helicopter.