10 replies to this topic

[Slotrodder]

I'm reading about C-can and D-can motors. What's the difference? For example, I see Hawk 7 and 9 a lot, what are they classified as?

 

Also the drilled and tapped mounting holes, usually 3, are they SAE or metric? Are they common in size, what diameter and pitch?

[MSwiss]

2mm is the correct thread for most (if not all) motors from China.

[Paul Menkens]

The D cans are the size of the original Mabuchi 16D motors that were used in many cars beginning in the 1960s. Several American companies sold high performance "rewound" motors based on these motors, notably Mura, Lenz, Dyna Rewind, Cobra, Champion, and many more.

 

Newer motors such as the Parma Super 16D and Mid-America Condor (and others) are roughly this same size. I have several 50 year old plus Mabuchi 16Ds that still run great.

 

Mabuchi also made larger and smaller cans but it was the 16D that came to be run by the pros.

 

When the American motor companies moved away from rewinding Mabuchi motors and tooled their own cans, they moved to a slightly smaller size, the "C" cans, you can usually fit a C or D-can into the same frames.

 

The Hawk 7 and 9 motors are two of many "throw away" motors on the market, sometimes a particular "throw away" will be included in a race entry fee, in that case it is called a "hand-out" motor. These often look very similar to each other but can be much faster or slower depending on the model. These motors are designed to not be able to be taken apart and rebuilt, just thrown away when they get worn out, parts are available for the D and C-cans so they can be rebuilt several times before they are trash.

 

Hope this helps and there are many here who know a lot more then I do about this so I hope they will correct any errors I have stated.

[Slotrodder]

Thanks so much for the feedback, it really clears the air. So much has changed since the '60s when there was a Pittman inline and the 704 sidewinder.

 

Thanks again for the info.

[Bill from NH]

Comparing C-cans & D-cans, the C-can is shorter, narrower, not as tall, & generally has stronger magnets. Often. but not 100% of the time, both will fit the same motor mounting brackets. Both C&D-cans can provide a lot of racing fun.

[Dominator]

C-can and also significantly lighter than D-cans.

Fk style motors are the lightest. I believe they range from 22-26 grams?

[Bill Seitz]

The Hawk motors mentioned are typically referred to as "F" or "FK" motors and are slightly smaller than both the C & D cans. They're similar in size to the old Mabuchi 13D motors from the 60's, though the FK's are shorter. The can heights are: D - .650", C - .625", FK - .605".  C & D are similar width, but D is 1.25" long while C is about 1.13". The FK length varies slightly from 1 - 1.1", but is near .2" narrower thanks to slimmer magnets. Slimmer magnets were never a draw to the 13D motors, but better magnet material today have made the FK motors popular. Surprisingly, C-can and FK motors are very close in weight and fall in the same range together. Depending on the armature used in the D-can setup, the weights can run from the upper end of the C-can/FK range to around 35 grams. Motor brackets for C & D motors are often interchangeable, and the FK can also work in them, but FK specific brackets have the wrong mounting hole pattern and are slightly too small for the larger motors.

 

"D" armatures are generally .002 larger in diameter than "C", but a similar length, and in some cases armatures for one size can be used in the other. "FK" uses a similar diameter armature but is shorter and not interchangeable. Some FK motors use crimped-on endbells that aren't normally removable and are referred to as "sealed". Others, like the Hawk 6 and ProSlot's line of "Euro" motors, have removable plastic endbells similar to the C & D motors.

[John Luongo]

the magnets can be quite strong in an fk motor. enough so that a short, removable end bell can be adapted to an fk can with a super wasp arm for something different, light weight and screamingly fast.

[Bill from NH]

Not all FK motors have carbon brushes, some have metallic. There are two different lengths of FK cans, If my memory is correct, they're 140 & 180 mm. I'll have to double check those figures, I have both.

[gotboostedvr6]

All brushes are carbon, some have extra metal but for sure mostly carbon.

[Bill Seitz]

What Bill Fernald may be referring to is that these same size "F" motors (FA) are also made with metal leaf "brushes". They're sort of like the metal arms of the crimped endbell carbon brushed motors without the carbon-metallic puck on the end. Low voltage, low performance types of course. Most of the ones I've seen are rated for 3-volts, milliamps, and not more than 10,000 rpm.