Motor Recommendations

[Shaun Hendricks]

I've noticed I keep learning more about different motors (UMI pointed out those killer maxon ones in a different thread).

So, I figure I'll give out some spec's and let all of you take a wag at it. Here's what I'm looking for:

High Torque Motor
12 volt capable
6 Amps or more capable
must be 1300-1700 kv
can be brushed or brushless
can be inrunner or outrunner
must have 500 series mounting holes
1/8th inch shaft or adapter for 1/8th inch
Planetary geared okay but not preferred

Best of all: try to keep it under $100 Amerikin :D (sic)

Any takers?

[Ghost 2501]

car wiper motors? tried those? blower motors???

[SDJ]

I have pulled several car wiper motors from cars, even the small ones from the tailgate of station wagons are quite big compared to 500 size motors, though they are great high torque motors and I will use the 2 I have in a paddlewheeler.
The 2 rechargeable 12v drills I have bought and stripped had 500 size motors that run at about 13,000 rpm, shafts are about 3mm, both have 500 mounting holes, the good thing is most people throw these out as the batteries wont hold charge, motors are usually still good. :)

[frankg]

:) SHAUN HENDRICKS- MACK PRODUCTS makes a very powerful marine motor model #5045 which runs on 12 -14.4 volts and a low amp draw to boot. This model marine motor is used in most of their power packages and give outstanding performance and run times and with out water cooling. Their web site is www.mackproductsrc.com
:)

[Shaun Hendricks]

Frankg:

That is a nice motor, it has a 991kv by my fast calc assuming their RPM is a loaded one. If it's free-running it will be much lower than that under load.

SDJ:

Yup, some classic reccomendations there but hard to quantify 'car wiper motors'. :D The drill motors usually have specs laying around but they are generally built for durability and not performance. Thanks for the suggestions!

Ghost:

Never tried a blower motor. Maybe a fan motor but those might be getting a bit big for the application.

Anyone else? Still looking for takers on the challenge! What's the best motor to meet those specs? :D

[der kapitan]

Shaun, I'd go with the MACK motors. They are 05 types that have custom wound armatures and are specially made up for economical performance.

[Shaun Hendricks]

I'll give it a try... couldn't hurt, right? LOL! :D

[green-boat]

You could add either one of these to a 550 motor.
http://rc4wdstore.com/index.php?cPath=61
Here are a few more on this page.
http://rc4wdstore.com/product_info.php?products_id=515
Also search here for lathe motors http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXLYV4&P=ML
Lathe motors have more turns per pole so they turn slower but have more torque and longer run times. They come in 55, 65 and 75 turns per pole. Also instead of 550 motors, look for a 555 motor. A 550 motor has a 3 pole armature where a 555 has a 5 pole armature or anything that ends in a 5. More torque, lower speed and longer run times.

There is a guy in our club that uses automotive power seat motors for boat motors. They have plenty of torque so most times you don't need any kind of reduction. If you think about it a used blower motor has more wear on it where a power seat motor doesn't.

[Shaun Hendricks]

Hmmm Interesting finds green-boat....

I like the lathe motors and the gearboxes. There's a 35T motor there also! I think I might try the Integy motors if I can find the actual motor specs someplace.

I also like the Mackproducts motor but it's kv may be a little low for me at 12v... maybe, if I can overcome it with gearing... hmmmm.

[pompebled]

To give you an idea of the difference in size:

A car fan motor, next to a 900 closed can motor.

Regards, Jan.

[green-boat]

While at work today I came across some 555 motors for $6 each. :eek: I bookmarked them but forgot to email them to myself so I could retrieve them here at home. I will do that tomorrow and post the link here. I just may have to buy 10 or 20 of them at that price.

I blame those R/C crawler links on someone here. They had posted a YouTube link of their boat video and off to side was a video of an R/C rock crawler that caught my eye. For the past two weeks I can't them out of my head. I'm seriously considering building one. :rolleyes:

[Shaun Hendricks]

Kyosho has a little micro "Range Rover" that out of the box does a dang'ed decent job of rock crawling. The thing's a mountain goat but doesn't have a high clearance so gets high-centered a bit easy. Kind of fun to play with on big smooth rocks though!

As for motors. I went out to allelectronics and ordered 3 different motors with different spec's. At $3 a shot, it will give me some play room.

I looked at the Mabuchi site and while their 555 looked good, it's KV was way too low. They had a 540 that was near perfect and their 550 looked very good too. I'd probably start with the 550 and if it was too slow, drop down to the 540. What I like is their on-line simulation software. Very neat! You input the voltage and it spits out the graphs and performance curves.

I'll keep y'all posted on which motor ends up working best for the application, which I'll keep under wraps... it's probably not what you are expecting! :D LOL!

[Umi_Ryuzuki]

My 56" Italian Mastrale class destroyer ran for a decade on a pair of
Dumas 4.8volt motors, run on 6v battery. The only reason I changed them out was
to take advantage of the better bilge pump water sensor function on 12volts.
At that point I switched to some 14v(8314b703) Pittman motors that were
pulled out of hospital centrifuges.
Both sets were run direct drive, and wired in parallel and run off of a single ESC.
The Maxxon motors are run similarly.

I tried to use some Pittman in my SDM tug, but didn't have enough rpm for the
small Graupner 1761 schottle drives. Ron Burchett recommended that I run the
Graupner Speed 400 with the 2.33:1 gear drive. The tug has performed beautifully
ever since.

[Kmot]

green-boat: For a moment there I thought you were a rock crawler, scale 4x4 r/c nut! :D

I was very active in the r/c monster truck scene for awhile. I am very familiar with RC4WD, its rise, fall, and re-birth. As for those inline gearboxes, I am the first one who used those in a r/c truck application. In fact, Brian Jones, who is the owner of RCP Crawlers (http://www.rcpcrawlers.com/) is the one who machined the adapter I needed when I was setting up mt TXT-1 to use the inline gearboxes. I sent him hand drawn plans and he made the adapters. Only he wasn't used to working in millimeters, lol. Then later, a guy who owns a biz named RC Alloys, Inc and makes things for r/c monster trucks asked me if he could use my idea to make a commercial unit and wanted my dimensions, setups, etc. Since I had already posted detailed photos and descriptions of every step along the way there was not much I could do to stop him, lol. But I guess he didn't make a go of it. Hua, the owner of RC4WD is quite adept at adopting ideas he sees on the internet and then getting his suppliers in Asia to crank out parts. RC4WD sponsored the first official rock crawling competiton a few years ago, in 2003. I was in it, and it was also photographed by RCCA magazine. My trucks photos were in the article. I also made a DVD of all the competitors runs, and Hua asked me for a copy of the DVD so he could give it away to his customers that had been asking about getting video. I gave him a DVD and he made copies and sold them on his site for $15. In return I have yet to realize a penny from that. In fact I have yet to realize a penny from any of the video work I have ever done! :rolleyes:

[Shaun Hendricks]

Nice Truck Kmot! It shames my efforts! :D

If the motors I've ordered give me a broad enough 'plug and play' spectrum I can identify a higher end motor with similar specs. I've done the math on all this but load is a variable I won't know until I plug it into the application and the motor needs to handle the dead starting load but also have a good 'wind out' speed.

[green-boat]

Here is the link to those 555 motors http://holmeshobbies.com/product.php?productid=38&cat=3&page=1

Kmot,

Nice looking truck you have there. I'm still planing this truck on paper, it's getting expensive. I started playing with the R/C cars back in the late 70's with a 1/12'th scale Jerobee gas car and then to the 1/12'th scale electric Jomac indoor car. I never got into the electric/ gas buggies and trucks that you see out there now. This rock crawler thing has got my brain running overtime. Currently I'm looking at the Raptor axles from RC4WD and the Stick chassis from the Crawler store. It looks like it would be easy enough to marry the two together. I've heard rumors that RC4WD is working on CVD's for the Raptor axle. Hmmmm

[Shaun Hendricks]

Many Crawlers are totally custom built. I saw one that was fully articulated in yaw and roll with independent suspension and independent motor control to each wheel. Most of it was just machined out of standard stock and parts from other cars/trucks.

It's nice to know that boats aren't the only platform needing low speed and high torque motors! :D

[Kmot]

RCP and the Craler store have specialised crawler stuff. as well as RC4WD. But, have you seen the new Axial all in one kit coming soon?

http://www.axialracing.com/ftp/Press-Releases/04-07/AX10.htm

[green-boat]

Kmot,

I have seen the new Axial kit, very impressive. Considering what's all included, it's not a bad price to say the least.

[Shaun Hendricks]

I just got the test motors in yesterday from www.allelectronics.com. Fast shipping to here in California! I'm going to start with the longest (likely highest torque) motor and test from there. We'll see what happens!

[Kmot]

Which ones did you get Shaun?

[Shaun Hendricks]

Johnsons.... DCM-231,DCM-266 & DCM-267

Those should give me a chance to get the best specs for a higher end motor, but even then, should run quite a while. :D

[Kmot]

Shaun, I bought all those motors also. I am pretty sure I put the DCM267's in my PT boat. And they perform very well on 6 or 12 cells. On 12 cells, they blew my Graupner u-joints apart.

[Shaun Hendricks]

Okay, had a few minutes to spend in the garage testing these motors. I used a 0-25v Power Supply 5A max current to test with.

For the loading I used an MAS 6x4 3 blade air prop. That's enough to drag down about any motor. :D

I tried to test at the 11.1v and discovered immediately that it put my power supply into the red zone for current draw. So, I ended up backing it down to 3v for a comparison test of all 3 motors.

I used a Hobbico Tachmeter and a consistent backlight source for the testing.

DCM-231
5720 rpm @ 3v-4.6 Amps

DCM-266
5200 rpm @ 3v-4.3 Amps

DCM-267
3200 rpm @ 3v-2.8 Amps

The 231 & 266 were nearly identical and shorter canned than the 267 so I wasn't surprised. I was surprised by the 267. For giggles I decided to bump the voltage up until I hit 5 Amps. I hit 8v and 9,000 RPM turning that prop! :eek:

So it looks like the 267 is going to be my first victim for the actual application test. It looks to have the right spec's under load, about 1,100KV and that should put me at 12,000 rpm in the application and that motor WILL be under LOAD!

I don't doubt that motor twisted the Graupner u-joints to bits. Any friction in those joints at all and it would make enough heat to let the torque twist them to bits after all, you were probably turning close to 19,000 RPM's on your props Kmot... I'm surprised you didn't cavitate the propellers...