Tech thread: CrawlMaster 540

[JohnRobHolmes]

Do you like brushed motors, but need more creep on the low end without sacrificing the top speed? I have been developing just the motor for you I have spent months perfecting the build and wind pattern for these, and I am finally satisfied enough with the final product to put my name on it. Winding a three slot is cakewalk compared to these little beasts!

For up to date features and pricing, visit our website Holmes Hobbies / Holmes Bikes :: Motors :: Brushed :: CrawlMaster Pro 540

Basic Tech specs of the motor

* Hand-Wound Armature – Our pro-level armatures feature a 1-3 pattern hand-wound wind with specific wire sizes developed to take all that your high power electronics can dish out. We optimize copper fill for best power and torque. Wind termination is reinforced using high-temp alloys using the most advanced machine available to prevent comm damage. Coils are impregnated with state of the art epoxy resin. All armatures are then perfectly dynamically balanced with epoxy and the commutator is diamond trued. All armatures are stamped with wind. One cannot build a finer or more precise armature!

* Standup Brush and 7.5mm Comm- Maximizes torque and motor longevity
* Gold plated copper brush hood to resist corrosion and provide lowest resistance
* 5mm web 5 slot armature- Maximizes torque, efficiency, and low speed control
* Can – 1.4mm thick can features minimal venting and two high-power FB9 wet magnets to maximize torque and efficiency
* Onboard Surface Mount Capacitors – Helps eliminate unwanted radio interference caused by electric motors
* Dual Ball bearings
* Adjustable timing

Here is the no hype, no fluff bottom line-

Low speed resolution like no other brushed motor, even the Cobalt Puller!
MUCH longer service life due to reduced comm arcing
Ability to run at zero timing without negative consequences
Reduced arcing at higher voltages
Higher efficiency than three slot, especially skewed or slanted versions

But of course you can't get something for nothing...
Construction takes much longer, the little bastards
Drag brake is slightly weaker unless Active Hold is engaged



I have been testing a set of 13.5t in my XR10 since Nats this year, and I have been very pleasantly surprised all around. They run right at the same speed as a 27t, but I can run them on 4s lipo and still have plenty of low speed crawl. And I do mean PLENTY! With stock gearing on the XR10 I do not have to engage Holmes Hold, standard drag brake is plenty to slow down the rig. While they are not quite as punchy as the TorqueMaster 540 counterpart, there is more than enough power to break parts. I would consider the feel to be more linear, they are easier to control.

We have the most experience with high slot count motors, and constantly test and tweak our construction for the highest quality. If you don't see something "fancy" listed you can rest assured it is not needed. We guarantee you will be satisfied, or your money back!

So what does it add up to? While they aren't for every rig, I won't be running three slot arms in my 1/10th scale rigs any longer! These are just too dang smooth.


Here is a little sneak peak of what the motors are capable of. Low speed control without sacrificing wheelspeed? That is what this motor is all about.

Holmes Hobbies TorqueMaster & Crawlmaster test - YouTube

[Sparky J]

These sound awsome John! I'll be watching out for these

[kennyj]

You post this 1 day after I order motors?

[JohnRobHolmes]

The armatures are compatible between motors of course. It will be three to four weeks before we get the first batch done anyway.

[losikid]

Those are some nice looking winds, how much would just arms cost?

[JohnRobHolmes]

I will start a for sale thread when these are in stock and ready to go.

[Rootar]

hmmm "MUCH longer service life" how much we talking here compared to what you told me about your pro 540s.

I picked up a lathe and TONS of brushes and parts so I might give these a try but i still want the brushless to work out but hey there is no reason i cant run a pair of brushed motors on my dual rs's in the meantime.

[lsone]

not that i'm trying to start anything... but a friend of mine has been having brutal luck with low service life on his HH 35T motors. Maaaybe 10 packs out of a set of brushes, timing was set based on your thread. Is this normal? I have the most hacked together motor in the world and I am still on my first set of brushes and it is a fast little bugger, I wheel with him pack for pack so its not like mine sits on the shelf lol

Essentially.... Are these new motors very vulnerable to debri from a scaler rig?

[JohnRobHolmes]

If he is running 3s, 10 packs isn't that bad on a 35t actually. Of course depending on driving style and terrain and all. There are a lot of factors, but basically you have to pay for power in one way or another. If he swapped to a laydown brush or if we bumped the wire size down a 1/2 gauge he would see even worse motor wear.

I don't have quantitative numbers on the service life, just running off the seat of the pants testing right now. Once I finish building my dyno I can give a more accurate service life representation. They may not last longer running watt for watt with a 3 slot, the extended life I am seeing may be an effect of smoother power delivery that lowers the average amp draw or better efficiency at low throttle that reduces power consumption. At any rate it is an effect that I didn't really expect, but was happy to see.

[ecoli]

Hmm, interested. So are these the same dimensions as a typical 540 motor or a bit longer of a can? Overall, how would it compare to a puller in terms of performance (you noted better low speed resolution).

[JohnRobHolmes]

These are a 540 motor, in essence. Looking at one built up, you wouldn't know it was any different than a normal 540.

Performance on these is not as nuts as the Puller. They are easier to control, have less overall power, and do not produce as much torque. Hence, it also gives better runtimes than the Puller.

[Manning]

Very cool.

[JohnRobHolmes]

First post is updated with a vid and better armature pic. Check out the speed range, as well as the low speed resolution that the combo gives! I haven't used any other brushed motor with such great control!


The teardowns should be hitting the shores any day now, and I will start winding them up and start a sale thread on them.

[Reflection]

Count me in boss. My old 35t's have done well the last few years. Could use something new.



If they've got better bottom end/slow speed control over a 3 slot with a little more "snap" off the line.....those will be SICK!

[TURTLE]

So this or the 550 should be the ultimate TTC motor for my 4 cell packs?

[slowrockr]

Looks like a perfect fit to my driving style, I'm a slow creep kinda guy, till I start runnin out of time than it's rock race time.

[Tanis]

Just what the doctor ordered This will be my next motor
Thanks for continuing to improve and push the boundaries so we can further this sport.

[JohnRobHolmes]

Originally Posted by TURTLE

So this or the 550 should be the ultimate TTC motor for my 4 cell packs?

It depends on how much power you want and how heavy the vehicle. For a lightweight truck, it would be really awesome and allow a greater speed range without a two speed gearbox. If you are mud bogging however, The 540 version may not have the grunt you need to stay floating. There is a big brother 550 that is also in the works that would be better suited for bogging, but at that point you could also use a brushless motor that would take the mud and grit a bit better.

[ColquittCustom405]

the 550 sounds like what I want for 2.2. and a 540 for my 1.9.

[microgoat]

I still have that 5-slot 550 arm you sent me back in '05 I can't wait to try the new 540.