Holmes Team, Pro, and Custom motor Tech

[helhedded]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

The following set of motors is for multi-time National Champ J. Ripplinger. They are truly a custom set of motors. The endbell is machined and assembled from 540 parts. The can is made from chromoly. The faceplate is machined from aluminum. Setscrews for the can are stainless, and hardware to hold the endbell is 7075 aluminum. I populated the cans with N34 neodymium magnets with a special layout for best startup and low speed resolution. The timing rings are machined from fiberglass. Armatures were custom built for me by Sagami for prototype work. I wound them to just over 2500kv, a very peppy wind that is perfect for Ripplinger's style of driving. The pair of motors weighs 250 grams on the nose. A full 1/4 pound less than a pair of regular 540s! This motor is likely to become the Team Crawl edition Puller 500.

Many people have been demo'ing a very similar motor at USRCCA and Scale nats. They are very smooth driving, certainly worth the effort to build! "thumbsup"

Wow those custom motors have an impressive parts list! I'm anxious to put some of the new 500 pullers in my berg. Thanks for letting me run them at Nationals.. the speed and "pop" was unlike any motor that I've ever ran :shock:

 

[SDS Customz]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Totally stoked to get them here and give them a shot, the little bit I got to drive them they where very impressive

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

We have been plugging away at custom motors lately, I've been bad about updating the thread with all the cool goodies!


Here are a few Crawl Type arms we just finished up for a couple world champion drivers. These were wound with a little "twist" to help pack in more wire, along with a double wire. It isn't obvious in the pics, but the different termination allowed an extra 33% more wire on the 16t than typical without interfering with the commutator as would normally occur.

The 9t double (far left) along with the special termination allowed for a full 50% more copper than I had previously been able to fit :shock: This was borderline too much, there was one wire on the final pass that took a lot of encouragement to seat. It also has about 12% more wire than the 16t, but it did take about twice as long to wind and terminate. The 5 slot Crawl Type arms don't work too well with thicker wire, so using double strands will become standard practice for our "Team" motors where higher wire fills are standard.


You will also notice the kevlar reinforced wire. This is needed with the special termination pattern to prevent flyouts, as there is nowhere for the coil leaders to bond like on regular CrawlMaster type arms.


The construction of the arms was otherwise typical. We use oxygen free copper wire with 200c rated insulation. Wire termination was reinforced with a 650c high silver filler via resistance brazing methods with electrical specific fluxes to prevent copper embrittlement. A 200c rated resin was impregnated into the coils after winding. Then we dynamically balance with the finest German balance epoxy. Standard day at the office I suppose :mrgreen:


After we cut the comms they will get assembled into motors and sent out "thumbsup"

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Here is a little vid of a motor armature modification, machining the armature for rougher startup and more punch. Typically this is done before winding, but these winds were already sealed so there is no harm.

Machining a Custom Rock Crawler Motor - YouTube
<iframe width="560" height="315" src="http://www.youtube.com/embed/7gfy8O7wtIo" frameborder="0" allowfullscreen></iframe>

 

[YoUnG_vErSiOn]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

thanks JRH!! looking forward to the package!

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Got a batch of motor cans coming my way. Since these aren't actually a solidified brand, I'll call em customs

Puller 500 v4.6 (on the right) drops an additional 7 grams from the 2.xx designs. v4.5 (on the left) drops 3 grams. Both v4 designs reduce airgap by 50% to increase torque and brake. Up and coming v5.0 will be even lighter and have fewer parts for assembly, while boosting back iron to further increase torque and brake.

 

[sylvainp42]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

FB12 magnet cans are available with complete motors through the Pro Custom motor builder! Right now they are a $15 upgrade, only 7 cans are left. In 8 weeks we will have a large supply and the price will fall to a $5 upgrade.

Any news for the new fb12 cans ?

I'm ready to order 8)

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Last estimate was a shipping date of jan15th.

 

[sylvainp42]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Let me know, anyway it's snow everywhere here so I can wait a little more

 

[jacobflyin]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Last estimate was a shipping date of jan15th.

How do I get on this list "thumbsup"

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

FB12 cans should be here within a few days! All 2013 Team 540s will feature the upgrade.



The number of custom motors built has not been reflected in the thread lately, we have been too busy working in the shop. Some notables, however...

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

****** Mechanism Motor

This motor was taken on as a custom for a company. The needs were straightforwards in size, speed, and resistance. Imagine a super powered airsoft gun :twisted:


Meet Mr. Chunky, a 540 shelled motor with large rotor and Neo magnets. It will become the Puller TTC edition in product line. I produced an additional motor that will go into my Southern Buggy. More specifically I made a bunch of parts to test :mrgreen:

Bare motor and stock "540" can, it weighs 7 ounces and leaks 32mT. With flux ring and leakage 15mT it weighs 7.8 ounces, dropping the speed 8%.


Target KV was 700 to 900, terminal resistance 100 to 120mOhm.
First armature was 24ga 60t, 720kv and 140mohm, Fail.
Second armature was 22ga 50t, 833kv and 118mOhm. Pass
Third armature was 21ga 50t, 833Kv and 92mOhm, Fail but possibly higher performance

Small comm was used to allow better coil clearance. Try as I might, I couldn't keep a pattern at such a high turn count. Wire was still laid as neatly as possible still, not fed without care.

Termination is always done for best conductivity. We have custom formed silver/copper amalgams that range from 15 to 71% silver. Practice makes perfect, and I like to challenge myself often. The following pic is tying 16.5ga wire into a 7.5mm 5 slot comm. The tang just barely holds it, and rips off at the slightest mishandle of such beefy wire.

These commutators are more delicate than similar 3 slots. There is not much room to work, and the power to melt brazing filler will explode the comm and wire if not tuned properly. Fat wire sucks heat from the joint, needing increased heat. But I wanted to try it on a whim to see how it did.


Result is a 2700kv armature, 6t with 16.5ga wire :twisted: Mild speed for the low turn count, starts up butter smooth, and it should have plenty of kick. In reality I could rewind it with a double or tripple and increase wire fill 2x, the fat wire doesn't conform easily. After terminating this, doubles would be a cinch!

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Building a secret Shafty motor for some Team drivers


So they want light, they want torque, they want smooth startup, and they want drag. We could build a Puller 500, or we could build a motor with double the wire size at the same weight and speed. 28mm arm, short stack, neo magnets, plus some other tweaks to get us under the 5 ounce mark. Same diameter as a 540, but with a much higher drag and torque density. Startup is smoother than a regular 3 slot thanks to the perfected skew angle and magnet layout. Terminal resistance is also lower than the standard 540 for the same speed. Who says we can't have it all :mrgreen:

Secret Shafty arm on the left, regular 540 arm on the right. Who do you think would win in a tug of war :twisted:

 

[bigstu]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Wow. Great work.
I am betting you dream of this stuff, when you do manage to sleep...

 

[helhedded]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Building a secret Shafty motor for some Team drivers

"thumbsup""thumbsup""thumbsup"

 

[Szczerba]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Very interesting. :shock:

Love all the tech and build notes.

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Wow. Great work.
I am betting you dream of this stuff, when you do manage to sleep...

I have a notebook with about 15 more designs for R/C and just as many more for personal transport and industrial/ robotic use, I go through months where I dream constantly about motors. Lately it has been digital switch inductive bounce and bad tattoos that haunt my dreams :ror: I can't wait to show the next two brushless motors we are working on. While I wait for some parts on the 540 outrunners, I've been playing with 10lb robot motors for BIG crawlers.


After the next few brushed motor designs are proto'd I will start bringing out the custom lamination shapes. It is surprising how much information can be learned after building a few motors that would suck for crawling. Sometimes the best information is from the opposite motor. Case in point, startup on one type of 28mm armature is strongly affected by copper and iron saturation. The information was only learned after building an actuator motor for a private firm. They didn't care about low speed control, it just needed to make big torque when 12v was slammed on it. Old designs that I had considered useless because of uncontrollable startup have been revisited and determined to be useful at specific KV's and wire fills. Took a build that started up at 7000rpm and made it 3000rpm, a huge jump in controlability based on the information from an actuator. Made my week "thumbsup"

"thumbsup""thumbsup""thumbsup"

Very interesting. :shock:

Love all the tech and build notes.

I've been trying to make the time to share my work of late, its just been really hectic. We have made very large changes and upgrades to the shop and are adding new machines to the floor. Moved a wall and added 19 feet of benches too. In the next few days/weeks I'll start spilling more motor tech, I built/bought a few new machines to gather information with.

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

FB12 magnets are now a standard feature on all Team motors. I will have them available on the site individually tomorrow. It increases magnet strength 8% over FB9 grade, giving better brake and torque. More specific measurements on KV, detent, and stall torque changes will be made ASAP.

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

A fellow crawling enthusiast is wanting best drag brake from a set of "540" motors. He didn't want to sacrifice startup, but was willing to take more weight. Three words: Airgap Flux Density.

This draws the design to two focuses, terminal resistance and magnetic circuit efficiency. The following data was used to select the best fit using existing motor designs. To compare magnetic systems easily, one armature and endbell is tested in many cans. V4 cans were tested with increasing thickness of the back Iron, and two 540 cans were tested.

Base type: Team Flow 540 Crawler
3 slot, 5mm web, skewed
30t max wire
Epoxy balance
15% silver termination
10mm comm
2.58oz armature with shim
xx spring
Holmes Standup Soft Copper brush


Can, RPM @3v, no load, motor weight
v4.1 4900 rpm 1.5a (5oz)
v4.2 4525 rpm 1.3a (5.32oz)
v4.3 4300 rpm 1.4a (5.62oz)
v4.4 4100 rpm 1.4a (5.92oz)

540 FB9 4800 rpm 1.4a (6.52oz)
540 FB12 4697 rpm 1.4a (6.53oz)



Keeping the armature and endbell static lets us test the permanent magnet system efficiency. Slower speeds = lower Kv. Kt (N-m/amp) = 9.5478 / Kv. Slower motors produce more torque per amp and generate higher voltage when turned at a given speed. Higher voltage induces higher amp draw. The primary effect of depressing motor Kv is higher peak torque, brake (drag), and efficiency. The secondary effect is ability to reduce turns for a given speed, which lowers resistance and increases power.

TLDR: Lower speed with the same armature is a better motor.



To analyze the data, we look at motor speed and motor weight. The slowest speed is "best", but it can carry a weight penalty. Comparing a regular FB9 540 to either the FB12 or v4.1 can isn't a big jump in change, less than 3% speed either way. It is small enough to question the validity without a larger sample size. But the weight is a solid 23% loss in mass. Weight isn't really a factor on these motors though...

Comparing the FB9 to the V4.4 weight is a 9% reduction. The change in speed is a 14.6% reduction. For any given rolling speed this increases the brake available during "drag" or dynamic braking since we did not increase armature resistance. To change any spec 10% or greater is very noticeable, so we have an easy winner for the "high drag" needs. Lighter weight is just icing on the cake.




Upon sorting this data, we have two choices. Stick with the slower speed and reap mounds of torque, or drop a few turns /add voltage to convert our gains into extra power too.

You can guess which way I'm heading :twisted::twisted:

 

[JohnRobHolmes]

Re: Holmes Pro Custom and Team Pro Crawler 540 motors

Set of Puller 500 Flow SLs for KevG. Lightweight! Full 540 Power!

v4 Puller SL can
35t Flow armature
7.5mm comm
medium wire
epoxy balance
modded CheckPoint endbell
Copper brushes
Silver (stiff) springs
Polished black oxide finish

Final weight, 8.9 ounce for the set!



We will receive beta production parts for the Puller 500 motor soon, which will allow us to go into regular production volumes instead of slow custom sets. We have also begun the process of tooling up for a custom brush and endbell design for Team and Puller motors. It will allow for fully sealed motors and smaller motor diameters, along with better motor life.