Thinking about dyno's for brushed motors

Brushed, nicad, radios, etc...

Moderators: scr8p, klavy69

Dadio
Approved Member
Posts: 3772
Joined: Sun Apr 24, 2016 6:21 pm
Location: Guildford UK
Has thanked: 2108 times
Been thanked: 1896 times

Re: Thinking about dyno's for brushed motors

Post by Dadio »

Yes that's how it works , you need an ESC with BEC but that's been standard for a long time , you just turn the knob to the voltage you want and watch the amperage , adjusting the motor timing while its running shows the amperage drawn so you get an idea of the sweet spot between high revs and reasonable amp draw , 1.5 to 2.5 amp being the target .
If a jobs not worth doing then its certainly not worth doing well.
A problem shared is a problem halved but an advantage shared is no advantage at all.

User avatar
R6cowboy
Super Member
Posts: 1014
Joined: Thu Oct 18, 2018 5:06 pm
Location: Mendota, IL
Has thanked: 485 times
Been thanked: 503 times

Re: Thinking about dyno's for brushed motors

Post by R6cowboy »

coxbros1 wrote: Thu Feb 18, 2021 7:00 pm If u have a 12v power supply or 3s battery this item will work perfect to adjust precise voltage to the motor and voltmeter

https://www.ebay.com/itm/12V-24V-48V-2000W-10-50V-40A-DC-Brush-Motor-Speed-Control-PWM-HHO-RC-Controller-/111851538617?_trksid=p2349624.m46890.l49292
Perfect, got 'er ordered up. Much cheaper than buying a spare esc and servo tester.
-Jerry-

User avatar
juicedcoupe
Super Member
Posts: 2874
Joined: Sun Aug 16, 2020 8:05 pm
Location: Pascagoula, MS
Has thanked: 223 times
Been thanked: 1644 times

Re: Thinking about dyno's for brushed motors

Post by juicedcoupe »

I'm still collecting stuff but this is what I come up with to attach the reflective tape to. I took a smaller spur gear that I had laying around and opened it up just enough for a pinion to fit snugly.

I haven't glued it together yet, but I spun it up on a 15T modified. It spun true, without any vibration or wobble. I figured that this would give me enough diameter to get a reliable reading without adding much mass.
Attachments
20210218_164228.jpg
Always looking for new and interesting ways to waste money.

User avatar
R6cowboy
Super Member
Posts: 1014
Joined: Thu Oct 18, 2018 5:06 pm
Location: Mendota, IL
Has thanked: 485 times
Been thanked: 503 times

Re: Thinking about dyno's for brushed motors

Post by R6cowboy »

juicedcoupe wrote: Thu Feb 18, 2021 10:50 pm I'm still collecting stuff but this is what I come up with to attach the reflective tape to. I took a smaller spur gear that I had laying around and opened it up just enough for a pinion to fit snugly.

I haven't glued it together yet, but I spun it up on a 15T modified. It spun true, without any vibration or wobble. I figured that this would give me enough diameter to get a reliable reading without adding much mass.
I was thinking maybe rigging up a small 3 blade propeller. Thoughts...?
-Jerry-

User avatar
coxbros1
Approved Member
Posts: 2161
Joined: Mon Dec 24, 2018 1:50 pm
Location: Energy, Illinois
Has thanked: 1903 times
Been thanked: 1697 times

Re: Thinking about dyno's for brushed motors

Post by coxbros1 »

Done the full dyno prop deal a few yrs ago testing 21.5 brushless for 12th pan operations...abandoned the setup shortly after making it.
It just didn't yield the results like we wanted. i would just stay with amp/rpm @ 7.2v no load....u will have more fun. plus the prop was dangerous
Tap pic for clarity: Derek

User avatar
juicedcoupe
Super Member
Posts: 2874
Joined: Sun Aug 16, 2020 8:05 pm
Location: Pascagoula, MS
Has thanked: 223 times
Been thanked: 1644 times

Re: Thinking about dyno's for brushed motors

Post by juicedcoupe »

I made this bracket with some scrap metal. 1" aluminum flat bar bolted to a piece of 1.25" steel bar.

I tried it out but it really needs something more substantial. It will stay upright while running but vibrates around. It will also torque over on a full power start.

I think a small selection 1X lumber and some non-slip feet would do the trick. It would also give me somewhere to secure the tach with a rubber band.
Attachments
20210218_200435.jpg
Always looking for new and interesting ways to waste money.

User avatar
R6cowboy
Super Member
Posts: 1014
Joined: Thu Oct 18, 2018 5:06 pm
Location: Mendota, IL
Has thanked: 485 times
Been thanked: 503 times

Re: Thinking about dyno's for brushed motors

Post by R6cowboy »

coxbros1 wrote: Fri Feb 19, 2021 1:36 am Done the full dyno prop deal a few yrs ago testing 21.5 brushless for 12th pan operations...abandoned the setup shortly after making it.
It just didn't yield the results like we wanted. i would just stay with amp/rpm @ 7.2v no load....u will have more fun. plus the prop was dangerous
My worry was those props aren't made to turn 30k rpm.
-Jerry-

User avatar
Coelacanth
Approved Member
Posts: 7342
Joined: Thu Jul 29, 2010 10:20 pm
Location: Alberta, Canada
Has thanked: 16 times
Been thanked: 265 times

Re: Thinking about dyno's for brushed motors

Post by Coelacanth »

For mine, I was thinking the same thing juicedcoupe has going, drill a few holes in a piece of L-iron or aluminum for mounting the motor, and bolt that to a small piece of wood. Keep it simple...yet elegant. :) The whole assembly would still be small and portable/storeable. No need even for rubber feet. Maybe I'll put something together this weekend using a hybrid idea of Dadio's and juicedcoupe's prototypes.
Completed projects: CYANide Onroad Optima | Zebra Gold Optima | Barney Optima | OptiMutt RWD Mid
Gallery - Coel's Stalls: Marui Galaxy & Shogun Resto-Mods | FrankenBuff AYK Buffalo | 1987 Buick GNX RC12L3

Dadio
Approved Member
Posts: 3772
Joined: Sun Apr 24, 2016 6:21 pm
Location: Guildford UK
Has thanked: 2108 times
Been thanked: 1896 times

Re: Thinking about dyno's for brushed motors

Post by Dadio »

I was thinking of 3d printing a rubbery disk with a hub that just pushes onto the motor shaft to use as an rpm sensor wheel and a mount like the one Juicedcoup did .
If a jobs not worth doing then its certainly not worth doing well.
A problem shared is a problem halved but an advantage shared is no advantage at all.

User avatar
Coelacanth
Approved Member
Posts: 7342
Joined: Thu Jul 29, 2010 10:20 pm
Location: Alberta, Canada
Has thanked: 16 times
Been thanked: 265 times

Re: Thinking about dyno's for brushed motors

Post by Coelacanth »

I'm thinking with the high RPM's and torque of some motors, you'd really want to secure the wheel, disk or whatever to the motor shaft, ideally with a grub screw. So probably modding a spare pinion gear would work best. A plastic wheel right on the motor shaft might get the center hole rounded out unless it's really secured well onto the shaft.
Completed projects: CYANide Onroad Optima | Zebra Gold Optima | Barney Optima | OptiMutt RWD Mid
Gallery - Coel's Stalls: Marui Galaxy & Shogun Resto-Mods | FrankenBuff AYK Buffalo | 1987 Buick GNX RC12L3

Dadio
Approved Member
Posts: 3772
Joined: Sun Apr 24, 2016 6:21 pm
Location: Guildford UK
Has thanked: 2108 times
Been thanked: 1896 times

Re: Thinking about dyno's for brushed motors

Post by Dadio »

Coelacanth wrote: Fri Feb 19, 2021 5:25 pm I'm thinking with the high RPM's and torque of some motors, you'd really want to secure the wheel, disk or whatever to the motor shaft, ideally with a grub screw. So probably modding a spare pinion gear would work best. A plastic wheel right on the motor shaft might get the center hole rounded out unless it's really secured well onto the shaft.
Won't take long to find out :) , just ordered one of the same rpm meter things as everybody else £8.99 delivered :lol:
If a jobs not worth doing then its certainly not worth doing well.
A problem shared is a problem halved but an advantage shared is no advantage at all.

User avatar
juicedcoupe
Super Member
Posts: 2874
Joined: Sun Aug 16, 2020 8:05 pm
Location: Pascagoula, MS
Has thanked: 223 times
Been thanked: 1644 times

Re: Thinking about dyno's for brushed motors

Post by juicedcoupe »

I ordered one of the tach's and speed controls last night. I already have a 12V power supply, DVM, and DC clamp meter.
Always looking for new and interesting ways to waste money.

User avatar
juicedcoupe
Super Member
Posts: 2874
Joined: Sun Aug 16, 2020 8:05 pm
Location: Pascagoula, MS
Has thanked: 223 times
Been thanked: 1644 times

Re: Thinking about dyno's for brushed motors

Post by juicedcoupe »

Dadio wrote: Fri Feb 19, 2021 7:09 pm Won't take long to find out :)
I like the idea of a lightweight printed disc. You would have more control of the surface that the reflective tape was mounted to.

As suggested above, I would still design it around a pinion gear. I like the idea of a metal hub and secure attachment. Even 540 sized plastic pinions have metal hubs.

Either way, it should be interesting.
Always looking for new and interesting ways to waste money.

User avatar
juicedcoupe
Super Member
Posts: 2874
Joined: Sun Aug 16, 2020 8:05 pm
Location: Pascagoula, MS
Has thanked: 223 times
Been thanked: 1644 times

Re: Thinking about dyno's for brushed motors

Post by juicedcoupe »

I thought this was interesting.

The Revenge of the Monster Pro obviously has the dyno sticker from Trinity, rated at 5V. The Green Machine 3 Pro looks to have dyno results from an outside source.

Given that they are both 27T, 24° Trinity Pro motors from the same generation, I'd expect somewhat similar numbers. The only other alternative is that the Green Machine was tested at higher voltage.

Also, the RoM's literature clearly states that it is a higher rpm motor than the GM3.

I haven't done any research as to whether Trinity tested all motors at 5V or if those may have been intended for 4 cell racing.


You can click on the pics for clarity.
Attachments
20210219_142937.jpg
Screenshot_20210219-143801_Samsung Internet.jpg
Always looking for new and interesting ways to waste money.

User avatar
Coelacanth
Approved Member
Posts: 7342
Joined: Thu Jul 29, 2010 10:20 pm
Location: Alberta, Canada
Has thanked: 16 times
Been thanked: 265 times

Re: Thinking about dyno's for brushed motors

Post by Coelacanth »

Interesting. That kinda makes me wonder how Kyosho rated the RPMs of their Le Mans motors, as their older motors were all intended for 7.2-volt NiCad batteries, but what about the later cars that were intended to run 8.4V NiCads and 240S-variant motors on those 7-cell packs--like the Turbo Optima and Salute, for example? I wonder if their "official" RPM ratings took this into account, or if they were all measured equally with 7.2 volts of battery power?
Completed projects: CYANide Onroad Optima | Zebra Gold Optima | Barney Optima | OptiMutt RWD Mid
Gallery - Coel's Stalls: Marui Galaxy & Shogun Resto-Mods | FrankenBuff AYK Buffalo | 1987 Buick GNX RC12L3

  • Similar Topics
    Replies
    Views
    Last post
  • Testing brushed motors with a Tekin 900 Pro Dyno
    by Frankentruck » » in Vintage Electronics
    14 Replies
    1357 Views
    Last post by Frankentruck
  • Brushed motor dyno
    by integra22t » » in Vintage Electronics
    18 Replies
    6036 Views
    Last post by RC10superfan
  • My brushed motors
    by REMJ666 » » in Vintage Electronics
    2 Replies
    1077 Views
    Last post by REMJ666
  • Are there any new brushed motors on the market?
    by m_vice » » in Modern Electronics
    10 Replies
    924 Views
    Last post by m_vice
  • Peak Brushed Motors
    by jeekelemental » » in Vintage Electronics
    1 Replies
    667 Views
    Last post by Dirtburner
  • Dave's Brushed Motors
    by DaveM » » in Vintage Electronics
    7 Replies
    1998 Views
    Last post by GoMachV
  • Refurbished Brushed Motors :)
    by jeekelemental » » in Vintage Electronics
    2 Replies
    1173 Views
    Last post by jeekelemental
  • Old school brushed motors
    by mc10ce » » in Vintage Electronics
    2 Replies
    1356 Views
    Last post by ChisaiKuso

Return to “Vintage Electronics”

Who is online

Users browsing this forum: No User AvatarAmazon [Bot], No User AvatarCommonCrawl [Bot] and 0 guests