25 replies to this topic

[Alchemist]

Are the Mabuchi and Mura Motors simliar in "Can" design or are they different from each other. The reason I ask is because I was reading something that stated something about Mabuchi designed motors and had no idea what they meant.

Thank you.

Ernie

[havlicek]

Hi Ernie,

While the early Muras used Mabuchi cans, Mura's own later cans in their bewilderingly diverse variations are only superficially anything at all like the Mabuchis. They're heavier metal, welded and not drawn, had a better bushing arrangement and of course the magnets had some real muscle right from the factory so buying hop-up magnets wasn't as necessary. Then there's the endbells, which you didn't ask about, but the whole Mura motor came from the factory with all the doo-dads already on there and could "take the heat". The motors kept changing and improving as well, unlike the Mabuchis which stayed the same after they got to the "FT" point as far as I know. Interestingly the Mabuchis are again cool because building them up, even with their limitations, is a creative way to experience what the people racing these in the 60's did.

-john

[Alchemist]

Hi John,

Thank you for the explanation. Materials aside, if you were to place the motors side by side, other than color difference do they look alike?

Ernie

[havlicek]

Hi Ernie,

Well, there's really only a passing similarity because both are of the same general type. They're both "flattened tubes" in shape for low COG with a metal can and a plastic endbell, but that's about where the similarity ends.



From left to right

1)A Mabuchi FT16D motor on the left. The steell insert showing in the can opening isn't stock. It's a shim with better Mura magnets in it. It also has brass sleeves (post protectors) over the plastic spring posts and the black endbell (while the same shape as the Mabuchi) is an addition made by Tradeship and is of better quality plastic. It's also one of my double wound #29s and is probably among the best FT16Ds I've ever done

2)The middle motor is Champion's version of the same sized motor (the ball bearing version). The can is really gorgeous...heavy one piece drawn steel plated with chrome. The endbell here is better and this motor has some upgrades as well...buyt the look is pretty stock. It's also a screamer

3)The right hand motor is a Mura "2-hole". On this motor, the can is formed from a piece of steel that is them bent and shaped with the sides spot-welded together to hold it all together. Basicly bomb-proof compared to the Mabuchi and even significantly better than the Champion for a bunch of reasons.

Having said that, I think they're all equally cool at this point. I sometimes wonder what would have happened if Mabuchi actually had chased the aftermarket upgrades and Mura to produce the best slot car motor they could have, but I think they didn't really care about the relatively small slot car thing. Philippe's book should have the best and most detailed information about all this stuff with the nitty gritty backstory and will most certainly make great reading. There's a lot of history and interesting facts with the stories of Mabuchi, Champion and Mura and there are people who really know this stuff a bazillion times better than I do right here.

-john

[TSR]

other than color difference do they look alike?

No they do not.

Mabuchi made several slot car motors before their FT line introduced in 1963. There was a previous "15R" line or large motors, long round things with two flats on top and bottom and virtually no can vents, used in many Strombecker and some later Revell models, all in the 1/32 scale. Most were gray in color, while BuzCo marketed some in a red, then metallic red color all through 1966, at a time when those boat anchors had long been obsolete.

The FT line came in two variations at first, the FT16 and FT36, both endbell-side driven and with a basic brush-holder arrangement.
Here is an FT16, marketed by Russkit as the "22". Cox, Revell and Monogram and most of the 1965 Japanese kits also used this motor, painted or plated in different colors. Below is the picture of a Mabuchi FT16:



The FT16 instantly rendered the previous top of the line Pittman 196B motors obsolete. It was lighter, less expensive and offered more possibilities to the rewinders.

The larger FT36 was used in early Revell, Cox and Monogram kits issued from 1965 through 1965. It was also recommended in some Japanese kits that rarely came with a motor included in the parts.



In 1965, Mabuchi upgraded their line and added the letter "D" to the name of the motors. The new motors were mostly can-side drive, and featured better commutators, improved brush holders arrangement and fatter wire. While the new Russkit "23" retained its small "blind" can bearing, most other new FT16D motors featured, as the new FT36D, a larger brass housing for a self-aligning gimball-style bearing.
A new, smaller motor was also introduced, called the FT13UO, a can-side drive motor with the same basic brush arrangement as on the older FT16 and FT36 motor, that was used mostly in 1/32 scale open-wheel car designs, as well as in the famous Cox "Lil' Cucaracha" model.

In 1966, Mabuchi introduced a "medium size" motor, between the FT16D and FT36D, called the "FT26". This was available in endbell-side and can-side drives, the can-side driven model being the FT26D.

This is when George and Ron Mura became involved, briefly producing rewound FT36 motors, then almost immediately concentrating on FT16D motors, mostly with endbell-side drive, then the new FT26 motors. Below are examples of such. First, some FT16D retaining the small blind can bearing:



Then, a later FT16D with the larger brass can bearing housing:



Then, an FT26D, this one a scarce dual-shaft model:



In 1966, Mabuchi upgraded their FT16D line with a new can featuring an oval vent and a ball bearing in what was now an aluminum bearing housing of the same design as their previous brass model, so as to match their FT26 motor. By this time the FT36D was abandoned as it was clearly obsolete, but millions had been produced and kit makers had plenty of inventory for years to come.
Mura used both long and short versions of this new FT16DBB can as it is known, for their most popular rewinds, sold in the tens of thousands:



By 1967 and after disputes arose in the whole industry with rather unwise decisions by the Mabuchi family, Mura as well as Champion introduced their own American made motors of the same size as the FT16D, in the case of Mura, the "M400", of which many versions were produced through 1970. This motor used magnets first produced for another motor, the Globe/Versitec SS101, forcing the use of a large shim that completely enclosed the magnets. Here is the original, version:



The first type used a copy of the Mabuchi endbell but with a much better quality, higher temperature black plastic. Later, Mura, after having hired the highly paid services of John Cukras, copied Champion and introduced better "pent roof" brush holders and an even better plastic material, now molded in a creamy color. Here is a rarer "Cukras Signature" example that benefited from many improvements over the previous models:



In 1968, Mura made a huge mistake and introduced a "flatter" version of their M400 motor, now able to use the now-thicker magnets without shims on top and bottom, called the "B", that was also made in many and all unsuccessful versions. Below is one of these many, many versions:



After two years of trying to sort out this motor (that also led to the use of larger motor brushes that became the industry standard to this day), Mura hired the services of Bob Green, an amateur racer who had used a cut-down, hand hammered version of the M400 around the better, taller but thinner Champion ARCO magnets. This became the "C" can motor, a smaller version of the M400 that could actually fit inside a FT16D motor. This became the motor used until the mid 1980s in mostly the same form, until the advent of cobalt magnets. Here is the most popular version (at right) next to an older M400:



That's pretty much the story. Got it?

[havlicek]

...see?...I told you Philippe had the info! And that was the short version too!

-john

[TSR]

It is indeed the very short version. The long one is safely kept for publication in the book pages.

[TSR]

After drinking my morning tea, I corrected some points and added a bit more info to my post, to make things clearer. Better have a new read...

[Prof. Fate]

Hi

And a minor point not really in the "story". The above Champion in John's photo is a mabuchi I believe. Bringing it up illustrate the problem with the labels involved. The short version is that, then and now, there was a lot of confusion on the sourcing of these things. A second minor point, the early 36ds started showing up in kits like the Monograms in time for Thanksgiving '64. But the motors, the 36ds showed up as singletons at tracks on the east coast where I was racing. Most people had no idea what to do with them initially. All came with a set of "sort of" motor mounts that would not actually fit any of the early kits until Monogram and Revell came out with chassis specifically FOR the 36d.

In the hobby, we usually refer to the first Mura Version of the 16d can as the "A" can. I have no idea why. I suspect it was because of the Mura "B production" being called "B".

Fate

[TSR]

And a minor point not really in the "story". The above Champion in John's photo is a mabuchi I believe.

Hi Rocky, no it is not. The "517" can shown here is indeed a Champion product, made in America. You will read the whole story inn the new book, soon.

Also you must stop calling early FT36s motors, "36D". That will confuse new generations.

Pre-1965 large Mabuchi motors with basic brush holder: FT36.
Post-1965 large Mabuchi motors with new endbell and improved brush holders and can bearing housing: FT36D
Regards,

[havlicek]

Hi Rocky, no it is not. The "517" can shown here is indeed a Champion product, made in America.

Yes, and to further clarify, it's one of the ones with the beautiful finish. I believe that later on, the had some that were pretty roughly machined and had large brass bushings pressed onto the can. I forget the backstory there, but maybe that was happening when they were not doing so well...or trying to use up inventory or using a different supplier or...different tooling or some other intrigue. Those are nice, but nothing at all like the one pictured.

-john

[TSR]

John, that's correct. The first issues had the can bearing in the form of an identical ball bearing as that of the Mabuchi FT16DBB and FT26, but permanently affixed in the aluminum housing. A second generation had a sintered bronze bushing in place. A third generation had a shorter aluminum housing still with the bushing, now visible. The last generation is the one you are talking about, and those were reject, unfinished cans that were recycled for use in low-cost RTR models in the early 1970s. When Carl Ford sold out of these parts to REH, lots of them ended on the open market.

On your motor, you are using a screw to attach the can to the endbell that is not the correct type. If you wish to make this motor visually perfect as they were, I can spare a few of the original, PM me as needed.
Regards,

[havlicek]

John, that's correct. The first issues had the can bearing in the form of an identical ball bearing as that of the Mabuchi FT16DBB and FT26, but permanently affixed in the aluminum housing. A second generation had a sintered bronze bushing in place. A third generation had a shorter aluminum housing still with the bushing, now visible. The last generation is the one you are talking about, and those were reject, unfinished cans that were recycled for use in low-cost RTR models in the early 1970s. When Carl Ford sold out of these parts to REH, lots of them ended on the open market.

On your motor, you are using a screw to attach the can to the endbell that is not the correct type. If you wish to make this motor visually perfect as they were, I can spare a few of the original, PM me as needed.
Regards,

Thanks for that additional info Philippe. I knew the screw was a faux pas (as is my sticker on there), but don't have any as they are like the proverbial "hen's teeth". Thanks for your generous offer too...PM on the way!

-john

[don.siegel]

To further confuse matters... here's the aforementioned Mabuchi 15R in the upper left, a red Buzco X-10 version; the gray Strombecker version was better known and very widely used. The story I had always heard was that Revell went to Mabuchi and said, design us something like this, but really made for slot cars, and that led to the first FT16, the Revell SP-500 that was in all their early kits...

[havlicek]

...cool stuff Don. I've gotten some of the 15Rs from time to time and usually just toss them I might even have one or two somewhere, but probably not. I still am fond of the Russkits though, probably because they were all over the place when I was a kid. Those and the K&Bs ARE slot car motors to me because of that.

-john

[Cap Henry]

Hey John, what do you use to paint your motor cans? Just regular spray paint?

[Alchemist]

Dokk,

Thank you for the wealth of information. John, I value your input as well as everyone else's - Thank you!

From what I see, is this what is called "endbell drive"?

John,

Are the motors you built for me called "reverse drive" motors?

I appreciate the education - thank you all!

Ernie

[havlicek]

Hey John, what do you use to paint your motor cans? Just regular spray paint?

Hi Henry,

I use mostly Rustoleum and sometimes Krylon and then bake the cans for 1/2 hour at around 250 degrees. I let them cool down and they're pretty hard and well cured afterwards. Some colors from either manufacturer seem to definitely get harder and more durable, so when I find one that works well...I use it a LOT The Krylon purple I've been using lately is like that and gets a really nice hard gloss when done.

Hi Ernie,

Most of the old Mabuchis (not all) were endbell drive motors. Some of them used a "C" clip kind of thing to retain the motor to the rear bracket by the can end. Then things switched to almost all can drive (for both inline and anglewinder) which is very soilid if you do a good job putting the screws in because you're fastening to metal. It's also nice because it puts the lead wire tabs in a much more accessible place and helps to keep them away from the bracket and shorting. Of course...if you know someone who likes to screw-around with motors, you can have a motor with the shaft on either end...or both just in case you want to make a slot car sidewinder with a positraction rear end!

Then there's the question of which direction the motor is timed to rotate faster. Lots of the old motors ran about the same in either direction, but people would check them to be sure as it was easy to swap the crown gear on an inline to have the motor running in the other direction. Lots of them also ran faster clockwise (viewed from the endbell). I think most all motors are timed to run faster counterclockwise now. Mounting a can-drive motor anglewinder makes this an important convention, but for inlines it doesn't matter as you can just put the crown gear on the other side of the pinion if necessary.

-john

[idare2bdul]

I know some people are in love with screwing motors into slot cars but I've seen too many where people actually distorted the can, either by hitting things(Doc!) or by cranking the screws too hard. The Endbell drive was easy to screw into but resulted in too much heat going into a delicate, heat sensitive part, bad idea.

In slot drag racing the norm is to screw the motor in because of the fear of losing any magnetism to soldering. If the can and chassis are pre-tinned the heat gets on and off pretty quickly causing a minimal heat up of the magnets, probably less than a run down the strip.

This ought to start a batle of the screws vs the solderers.

[TSR]

From what I see, is this what is called "endbell drive"?

So-called "endbell-side driven" motors have their pinion on the side of the endbell. Example:



While there is no pinion on this one, it is obvious that the protruding shaft is designed to receive one.



So-called "can-side driven" motors have their pinion on the can side. Example:



Got it?

[Alchemist]

Hi Dokk,

Thank you so much for the photo examples and the education!

Ernie

[havlicek]

...and then there's the whole Champion part of the story Ernie, only barely touched on here. Sometimes leading and sometimes following the industry...and sometimes just using up inventory! If you do a search here, Philippe has posted lots of info on all that as well. If you (and others) want to get into the nitty gritty of the vintage thing, it's worth looking for, as the motors AND the history is very interesting. Also, Rick T's builds always have great documentation about the cars and motors...as well as the builders, designers and racers (including Philippe, Tony P and a whole bunch of others). Edo (the Kingie of Thingies) has LOADS of period cars with the motors...often period rewinds, so checking back through his "A Thing About Thingies" threads makes some cool reading. This is all stuff that I knew little-to-nothing about when I was a kid and this place is a great resource for the history, not just what's going on now. Of course, Philippe's long-awaited new book will put this and a bunch of other info all in one place...no searching involved so, books are still cool even in the computer age

-john

[TSR]

Champion's own mess HERE...

Infamous Mura "B" motors HERE...

[havlicek]

Thanks for those links Philippe. It's been a while since I last saw them posted here, and there's sure a lot of very interesting info. Re-reading it, I got a laugh out of the mention of the endbell retaining tabs on the 517 cans. I always thought that it would take a small jackhammer to bend those things over and sure-enough the article mentions how impractical they were on a can made of such heavy metal. One thing I never come across are those black Mura endbells made to fit the Mabuchi cans. There are seemingly a fair amount of the Tradeship ones still out there NOS, but the Muras don't seem to be around...even old and mangled. Were they also of a better quality plastic or just the same stuff as the Mabuchis molded in black with the Mura name on them? Was the hardware the same as the Mabuchis? I'm guessing that they were sold separately as upgrades for motor builders?

-john

[Prof. Fate]

Hi

In the green com days, the "timing" was set by a little peg on the back of the com that socketed into the fiber insulator on the arm stack. The slop was enough for plus/minus 4 or 5 degrees from the set. Usually a motor was set, facing the endbell, clockwise about 5 degrees. But that could be anywhere between minus 3 to plus 8 or so. Very silly. A "stock speed secret" in the day was to quietly hand turn the com to max timing and secure with a small drop of epoxy.

Kids, unaware of this, often felt anger that "equal stock" motors weren't very equal. The same problem shows up now with the plastic 1/32 RTRs using variants of the FC130. I know of several clubs who are trying to somehow test motors for handout at the club level that they are trying to match because of this variability. They don't know the "why" part, but are trying to solve it anyway. Particularly difficult for the groups requiring NC1/8s only.

Mike, in the day with the plastic endbells, actually one of the fun mistakes kids and adults made that gave ME an advantage was that of the screw thing. In the day, people commonly used a 2-56 pan head, and done wrong would actually distort the bushing or the bushing mount or just "squeeze" it making it slower and run hotter. Beat a lot of better drivers with that one.

When the problem was "fixed" by having little brass mounts for the bushing that screwed in separately, it just caused a new place where the average racer (not PdL) would get the bushing alignment wrong. I always thought THAT one was so that mura and champion could sell more arms!

Fate