3573 replies to this topic

[Prof. Fate]

Hi

Regular thread works, john, because it is really just an epoxy carrier!

Fate

[John Schoen]

I finally ran the SCX Little Terror in a car last Thursday. 25K motors are usually the maximum that is usable on our track, so I was a little bit careful at first. The motor is much faster than anything else and the controllability surprised me. It does not behave like an on/off switch and actually has some midrange that makes it drivable in the tight twisty sections of our track. All that power demands more concentration than usual, so I won't use it in an endurance race but it will certainly be used in sprint races. A great motor, John.

[Alchemist]

Hi John S!

Would you have any pictures of the car please?

Thank you.

Ernie

[Ed Miller]

John Schoen,
We are glad that the LITTLE TERROR held up to its name. The Motors are a very good update and nothing out there compares to the Little Terror ,the pro motor is nothing compared to these babies.
Keep us posted and thank you for purchasing and trying the LITTLE TERROR in the Netherlands.

Thank you John H. for all of his great work.
THE LITTLE TERROR's are available from S&E Raceway only.

www.seraceway.com

Thank you ,
Ed

[Bill from NH]

Anyone needing kevlar thread, try your local fly tieing shop. They use lots of it. It's usually available on Amazon & ebay as well.

John, those old arm shafts didn't fit old bearings either! At least not the GRW bearings from the '70s. 5-10 minutes with different grits of Flex-I-Grit sandpaper (mylar) took quick care of that.

[havlicek]

Thanks to all who peeked in here to see my dabblings :-)

Regular thread works, john, because it is really just an epoxy carrier!

Hi Rocky, I'm sure thread will work fine ...I know dental floss does However, the thread isn't just an epoxy carrier at all. As in other composites, the thread contributes characteristics the epoxy lacks and the resulting combination is stronger in different ways than either material alone.

John, those old arm shafts didn't fit old bearings either! At least not the GRW bearings from the '70s. 5-10 minutes with different grits of Flex-I-Grit sandpaper (mylar) took quick care of that.

Thanks for that Bill. It's a bit maddening when you forget until after you've altready assembled the arm so I always check first...now

Hi Ed. It was very cool that you even thought of messing with the SCX motors, because on my own I wouldn't have thought it was a worthwhile thing...or that anyone who raced these would be interested. I was wrong-o!

-john

[havlicek]

Motor's all finished and what jewels these Champions are ! It always blows my mind that they made these heavy-gauge cans (and chrome plated) in one piece and finished them to such a high degree. There's a lot of money in tooling and fabrication in these old motors that just gives them a really special appeal.

I've quickly come to the realization also that, for all the additional hassle involved with double winds, they are NOT just the same as a single wind three gauges heavier. They do seem to run somewhat cooler and draw less current and this #29Dbl just screams like it's being waterboarded by the CIA and yet draws a respectable 1.75 amps (no load) at a full 12V. It also seems that I could run the thing all day no load at 6V with it only getting a bit warm. This is still right on the edge for a Mabuchi-like motor and I have plenty of room to add a few more double-turns even on these thick-web blanks, but what a sound this thing makes! Between the wind and that lovely old .007" blank, the beautiful Champion can and the magnets that measure very strong for the era, this is a motor that I'm really pleased with!

-john

PS: Thanks to Barney for telling me about these thermal-type labellers. His labels were so nice that I got one for myself. The one I got is by "Brother" and uses various sizes, types and colors of tape and the labels are durable and stay put. You can do all kinds of stuff with the included software...even import full color pictures (not that you'd be able to make out what they are at this size) and they will be resized to fit and converted to B&W automatically. The included software isn't installed on your computer and every time you shut the thing off, the software is removed. I paid something like $25 for the machine and it's dead-easy to use. I think it should go in Rick's toys for retirement thread

[Kim Lander]

John,
I put the Mura 26/26 wind you sent me in a Koford wire chassis...geared it 10-37 and ran it on our 165ft Engleman...you should have seen the mouths drop on all the people watching....absolutely awsome...keep up the good work pal...later.
Kim

[Alchemist]

John,

Your work is always a pleasure to view! May I ask you please, what type of camera do you use to provide such vivid photos?

Thank you.

Ernie

[Edo]

Yes John!

Your work is such a pleasure to watch! I even enjoy to look at all those "modern" and "contemporary" motors you're doing!

Soon there will be a couple of Ts out of Howmet's R&D dept. which will be using your rockets you sent me a while ago.

I hope he hurries up!

Ciao for now

E

PS Champion you got there!

[havlicek]

John,
I put the Mura 26/26 wind you sent me in a Koford wire chassis...geared it 10-37 and ran it on our 165ft Engleman...you should have seen the mouths drop on all the people watching....absolutely awsome...keep up the good work pal...later.
Kim

You just made my day buddy

what type of camera do you use to provide such vivid photos?

I use a Sanyo "Xacti" and it's really not a very great camera, but if you use enough light it does OK. I still wind up brightening almost all the shots in Photoshop because of shadows and whatnot.

Hi Edo,

Thanks...the Champion is one of the nicest motors I've ever done. Sometimes I get lucky! I always look forward to seeing what you come up with and if Howmet R&D is on board, even better!

-john

[Bill from NH]

I take it the Mura 26/26 is 26 turns of 26 ga. rather than a double wind.

[havlicek]

Hi Bill,

Yes, and that's a hot wind for sure! The motor I did for Kim was a regular Mura 2-hole with no additional fancy doo-dads...elephant ears, shunts, spring insulation etc. but was a real runner. It was very cool speaking to Kim about all this and he definitely knows his stuff from talking with him on the phone. Probably the best part of all this isn't the motors themselves, it's getting to know people from all over the place...like Kim and you!

-john

[havlicek]

Another "one-off" weirdo motor. I got this one from Jeff Easterly and Rocky says it's some sort of Johnson or something like that Anyway, size-wise, the motor is smaller than an FT26D Mabuchi, but larger than an FT16D...so I'll call it an FT20D The can is heavy gauge, like a Mura and drawn in one piece with no seams, very nice! The magnets read somewhere around 1000 on my meter and that puts them significantly ahead of Arcos, so they could be a nice upgrade for a "real" Mabuchi FT26D. The arm is shorter even than an FT26D arm and the endbell hardware is a dead-ringer for the SCX RX42 hardware...but with larger springs and brushes The motor appears to be a real "missing link" between the old and the new(er).

Anyway, the first thing I did was to remove the riveted hardware from the endbell because it had the brushes riding on the plastic of the endbell like the earlier Mabuchis. Looking at the attachment hole placement and the center of the plastic spring posts that were inside the metal ones, it seemed as though I could wangle some Mura hardware on there. After a pretty fair amount of wangling (more than I thought at first of course), I got the Mura hardware installed and was able to get a brush alignment tool and arm on there to lock it all down. Fortunately the endbell plastic is very tough so the mounting screws really grab hard and it all seems secure, but I'm going to do more at a later date to tighten it up.

Next, I drilled some ventilation holes in the top and bottom of the can so the thing can breathe a little better. Then I removed the Mabuchi-style caged bushing, reamed the hole in the brass bushing carrier out and soldered a new bushing in the can. Just to pretty it up, I stripped whatever plating was on there carefully thinking it might be either cadmium (gak) or zinc chromate and sanded the can down to #600 and then polished it up to give it a sort-of "Champion" look.

Finally, I set up the arm with a Tradeship com because of how narrow the endbell spacing is...and still had to radius-out the inside of the endbell to fit the Tradeship. After that I did 70 turns of #29 wire because of how short the stack is. It came out at exactly .5 ohm and draws only 1 amp at 12V...sounding very nice and seeming to have a whole bunch of torque. Because of how short this motor is...much shorter than an FT16D, it would fit either sidewinder or inline. There's LOTS more potential in this thing (whatever it is) and having Mura endbell hardware, seemingly tough plastic endbell material, quite strong magnets and a really nice can would help for sure with a hotter wind. It might even qualify for bearings but, like the SCX RX 42 motors, this motor (whatever it is) is definitely worth messing with.

The itty bitty arm (same diameter as FT26D) with the Tradeship com:



Can end of the motor... left is the new version, right is how it looks stock:



Endbell end of the motor...left is new with Mura hardware, right is stock



Top view of the motors...new up front



-john

[Alchemist]

Another awesome gem John!

Is a higher amp draw like 3-4 amps a good or bad thing please? How does it affect performance?

Thank you.

Ernie

[Slotgeezer]

Now, THIS is why I sent John those motors... He understands the "options" available to modifying motors for slot racing use... I had thought that the magnets were "slightly better" than the Arco, Tradeship, or Mabuchi units, & will be investigating reports of an available replacement armature blank from another similar motor that could fit this set-up w/ 4-5 more arm lams than a "stock" 26D armature... Stay tuned, motor-heads!

As always, another fine job by John... As strong as those magnets are, even doubling the area of the cooling hole into an FK-style "slot" wouldn't be out of the realm of possibility, eh? ... I agree w/ the FT-20D designation... Great job, john... You da MAN!


Jeff Easterly

[havlicek]

Thanks Jeff and Ernie...but Jeff...what the heck are these motors?

Ernie,

There is a direct relationship between the power (usually expressed in watts) of a motor and the current it draws (in amps). Volts X Amps = watts if I remember correctly (if not, I'm sure someone will correct me!). So for a given voltage, say 12V, a motor that draws 3 amps will be more powerful than a motor that draws 1 amp...if they're both working properly. Remember, a spinning motor is going from one dead-short to the next as each pole is energized, so you can think of a spinning motor running from the burnout that's chasing it Of course, this is all more complicated because such things as efficiency, brush spring tension, magnet strength etc. all come into play. That's why I didn't say that the 3 amp motor is three times as powerful as the 1 amp motor even when they are both running on the same voltage.

-john

[Slotgeezer]

Yeah I know, John.... weird stuff.....

Motors were traded for by a friend, who after learning that they weren't actually 26D Mabuchi's gave them to me... I have three more of them, to send your way... You can push the limits, Dr. ... We have available victims... er ...patients!

I'll include a single loooonger 26D-sized arm from the motors I'm looking at on Thursday, when I mail-out that next box of insanity tomorrow ( if we're not washed away from the incredible rain we're getting! ) ... My "crew chief" Ron Kiyomura had bought one, & cracked it open to reveal a nylon comm ( not good ) but the longer stack, w/ more plates! ... This is getting better! LOL!

I e-mailed a photo of the Havlicek FT-20D to Mr. Dynamic... We'll see how he reacts...

Again, thanks, John... I have an even MORE interesting motor to send you, that'll wet everyone's curiosity... The set-up has merit, but only because there's no plastic to melt & stop the motor from running! ... The armature shaft looks to be 3/32", like a 36D... But, the endbell is cast aluminum! LOL! ... Here we go, 3 turns of coat-hanger, comin' up!

See? Motor-building is FUN!!!!!


Jeff Easterly

[havlicek]

I don't know where you get this weird stuff from Jeff...you have a slot buddy in Tajikistan sending you motors?

-john

[Alchemist]

John is the "Maestro" (master of an art) of motor rewinding!!! I'm gonna refer to John H as "THE Maestro" from now on. Hope you won't mind John - er "Maestro"?!!

[don.siegel]

Hey Jeff, any chance of seeing a photo of that 36D monster? Sounds intriguing...

Don

[havlicek]

Hi Ernie,

I MUCH prefer plain-old "John"...it's appropriate and besides, there are real maestros here and I'm not one of them I try and make up for my lacking skills by being doggedly persistent.

Don,

If Jeff doesn't post a picture I'll try and get one up when I see the motor. Sounds like a bigger Russkit 25 or something. More motors from Tajikistan

-john

[Prof. Fate]

Hi

John, your VxA=watts is correct!

The real trick is that most people who dabble in motors, not you, are not careful and produce internal losses that up the draw without a gain in performance. In the "handout motor" field, that is the usual difference between "sealed" motors, subtle differences in alignment and such.

They are only toys!

Anyway, out there in mabuchi land is a wonderful piece for working on. After the 1970 re-do of the 16d, the dying of the slot boom ment things were static for a while. You may not have realized it but a 16d is 16mm thich, roughly. The 13uo is, 13mm. Anyway, in the 70s the next interation of the 1970 mabuchi design came with the ball races replaced by straight steel bushings, a 30s 65t wind in blue wire. But the ENDBELL is really good compared to other interations from Mabuchi. Very high temp. Anyway, it came with a thicker can so that the motor is 17mm thick! Did the relable it a 170? Na! They called it the "160D".

During the dark ages, Twinn K used it in their anglewinder womps called "Super 80s" which were designed in Sweden as "international 32".

The thing is that they are a perfect upgrade for the late 60s 16ds that used a snap ring mount on the can.

Fate

[havlicek]

Hmmm, cool info Rocky and I will keep a look out for one of those. People send me the darndest stuff

-john

[havlicek]

OK, so I'm on V2.0 of the "FT20D" motor project...AKA "the weird-but-cool motor Jeff Easterly sent me" First thing I wanted to take care of was the Mura endbell hardware. In order to get it all on there and line up properly with a brush alignment tool and temporary arm shaft, I had to open up one hole on each of the hoods and bottom plates. This made it difficult to lock down the hardware as the elongated hole really needed a washer to cover it. I also had cut lead wire tabs and installe those on top of the hood ends. So I cut new bottom plates with the tabs integral to the plates and that took care of part of the equation. To lock down the spring post end, I removed the standard Mura spring post covers and instead reamed out some modern Mura spring cups. When inverted, the flare end acts as a washer and perfectly locks everything down. Now I could realign everything and be sure it would all stay put!



With the beefy magnets and endbell hardware taken care of, it was time to do a new arm. I made a blank up using an old Tradeship blank and shortened it, which still resulted in a stack three plates longer than the stock one. I then removed the Tradeship shaft and installed a 2mm drill blank shaft as these are straighter AND stronger. The arm is a #26 sgl and with such a short stack, 40 turns still came it at around .2 ohm (I forgot to take pictures of the arm outside the setup). The result is way closer to a 2-hole Mura with 1 hole than a rewound Mabuchi FT26D...HOT and smooth drawing around 2 amps, maybe even a bit more. The motor spins up and down so fast, it feels like it wants to twist out of your hand doing either which is to me an indication there's some torque going on here. I may try some lighter springs to see about getting the current draw down a bit more and this setup could definitely use shunts at this power level, but the real weak spot now seems to be the endbell bushing. The only way to address that would be to install a bushing carrier plate and screw it to the endbell. For now, I think the motor kicks butt just as is. I don't know where it will go, but it would make one deadly sidewinder because of it's short length



Thanks to Jeff for sending me what turned out to be one very cool and unique motor!

-john