3573 replies to this topic

[havlicek]

Hi Robert and thanks. I'm partial to the 16D sized Mabuchis, but the 26Ds are also really cool. Heck, I may complain about them, but I also like the 36Ds too and I'll probably dive-in and wind one up and build a 36D with parts from the motors above that Allen showed.

-john

[Alchemist]

I never owned a 36D powered slot car - were these used in 4.5" chassis?

Thank you.

Ernie

[Prof. Fate]

Hi

In 63-5, the dominant 1/24 commercial track motor was the 36d. It was used in everything, including cars Duffy calls "lost causes". In the spring of 66, we got 26ds, at the end of summer, the hemi and better bits for the 16d made that the motor to race. Nothing to do with 4.5s or whatever.

Fate

[Alchemist]

Thanks for the info Rocky!!

Ernie

[havlicek]

This one's a replacement of an existing arm for John Dilworth (aka Howmet TX) that died. I'm pretty sure this goes in a FT16D Mabuchi...but after taking apart the old one, I found 31 turns of #27 wire!? That seems like an awfully stout wind for a Mabuchi, even with a Champion endbell and bulletproofing! Anyway, I built and spaced the arm to match his old one and after winding...I get in the mid .2 ohm range. Com is Mura, original stack/lams from a Mabuchi (his arm had .014" lams...but it wasn't a Mabuchi as it had a thinner inside profile), and it got a new drill blank shaft whilst I was at it. It balanced out very nicely and should be a strong runner. I just hope it's not too strong for the setup.



-john

[Alchemist]

Nice John,

Interesting how this arm, though polished, you can see the lam separation, while your other arms look like one piece!!

John,

What is your observation of Koford endbells as opposed to the vintage Mura endbells you like to employ in your hybrid motors please?

Thanks John!

Ernie

[havlicek]

Hi Ernie,

Interesting how this arm, though polished, you can see the lam separation, while your other arms look like one piece!!

I just didn't polish the arm down so much here Ernie, wanting to keep it the full diameter. Also, this somewhat depends on the way the laminations are stamped out and when each lam has more of a "radius" from the manufacturing process, you have a lot more of a "line".

What is your observation of Koford endbells as opposed to the vintage Mura endbells you like to employ in your hybrid motors please?

I'll use whatever I have as they're all good, but generally like the new or the old Mura stuff. For some things, the Mura endbells might work better just because of the shape of them, but other than that it's just about what I happen to have here. As for the Koford stuff, it's generally awfully nice and seems to have been engineered to a higher level ... their endbells being a good example. People don't send me that stuff so often, so I don't get to use it much and the Koford products are sometimes more expensive. If I had a choice, I'd probably be using the Koford C can endbells all the time, but the Muras work really well. It should be noted that some people don't like the Mura endbells because their hardware is on the large size...including the 6mm bushing/bearing hole. Other smaller aspects of the Mura can be a problem too...the brush spring retainer tabs are small and a little fragile. Anyway...I like them

-john

[Victor Poulin]

I'm with you John. I like the Mura hardware and use it on alot of my endbells,even if its not a Mura endbell. I like the size of the hardware, as it makes for a good heatsink. It does take a little more work to blueprint the set up, but the finished product seems to work very well.

Vic

[havlicek]

I just found this thread a week ago and you really have some nice arms and motor builds. So I thought I would show you what I have been using as 36d replacement arms and magnets.

This is a modern Mabuchi RS-360RH you can find them on ebay for $2 or $3.


Just pry up the 4 tabs on the endbell and lightly tap the arm to open it up.



You get a short stack .7ohm 36d arm with a modern com that drops right in to a vintage setup.
The arms not epoxied so you can rewind it. Or Tie,Epoxy and Balance the arm and use as is.


You also get strong modern magnets. With a little light grinding they drop in a 36d can.
I just use a bench grinder and flatten the ends and epoxy them in.
Original 36d on top RS-360RH on bottom.


Here is a completed motor that I use my Drag car.
It is much faster than a stock motor and is easy to replace an arm.
(and no its not an original 706 motor,its a copy. The collectors made the old champions to expensive to play with. )

I just received 5 of these motors from the eBay seller and that was PDQ so, judging from this one transaction he seems like a standup guy. At $10 + shipping, the deal was a no-brainer and worst case scenario...I figured I'd have some oddball motors to screw around with. Speaking of screwing around, I took one apart to see what was going on...but first spun one up on the power supply. Stock...the motor has some real "stones"...torquey and pretty high-revving as well at a low current draw. Inside, it looks like a F7, TSRF, S7 expanded and has the same brush arrangement...even with the oddball pre-broken-ion brush faces that people wondered about here regarding the mini motors (no...that wasn't a factory error).

Anyway, the arm and shaft are both exact 36D size and also very good quality with a nice heavy coating on the stack...a natural for rewinding. The arm is a "short-stack compared to the Mabuchi arm, but that's fine. I assume the arm lams are punched from good quality magnet steel...but have no way of knowing. The coils are not epoxied and should be very easy to take apart and the com is a lovely/modern heavy duty looking thing. There are some nice tight-fitting oilites on both ends, so I popped them out and saved those also...hey, you never know.

The magnets are slightly taller than would fit in an 36D can, but they should be easy to take down a little to pop them in. I tested the magnets (some sort of ceramic) and they read stronger than Mabuchis (then again...anything is stronger than those), but still about 10-15% wealker than Arcos. I haven't tried zapping them, but maybe they'll come up a little after they get hit??? I'm not even sure I can get them in the zapper with a slug, but they are an upgrade from the Mabuchis even if they are not up to the Arcos. Then again, absolute strength of the magnets doesn't always tell the tale...maybe they'll work well in a setup.

Anyway, if you're looking to rebuild some 36D sized Mabuchis, these motors can provide some good parts to bring those old boat anchors back to life! Thanks for the heads-up Allen

-john

[Victor Poulin]

Cant wait to get mine, I'm thinking if you got yours today John, I'll prob get mine tomorrow or the day after.
I was wondering how the arm would work in a Bobcat 36-D ? I got one or two old ones kicking around that need total rebuilds.
It might be interesting to see how these arms perform along with the upgraded mags


Vic

[havlicek]

Hi Vic,

Makes sense that yours should be there tomorrow as well.

I was wondering how the arm would work in a Bobcat 36-D ?

Not much guesswork there Vic. If you just dropped the arm and magnets into the K&B can/endbell, it should run pretty strong...probably like a decent period rewind. Even better would be to have the arm balanced, it will run faster, smoother and last longer. It wouldn't be a "cheater" in that it's performance wouldn't be like a modern fast motor...so in a way that would be cool. Epoxy and balance the arm and just install it in the K&B (my favorite line of Mabuchis!)...stick a fork in it and call it done

-john

[havlicek]

I received my other impulse purchase today and that was fast service. This time, I got two sets of neos from Emovendo at the suggestion of a Blogger who told me they were ridiculously strong. So today, I got a package that had
two pairs of these inside:


They're grade N45H nickle plated neos that are about a direct fit for the F7, S7, TSR minimotors. First thing I wanted to do was to see how strong they were with my meter...only problem was, I couldn't get them apart at first Eventually, I was able to separate a pair by sliding them against each other until I could pull them apart...they ARE strong. I stuck them in a can and they measured something like 15% stronger than the neos that come in the motor. The really bizarre thing is that both magnets are an exact match...not even off by a single digit, and I've never had that happen before. When installed in the minimotor can, the airgap is huge...something like .585, but I was told to not close up the airgap as you regularly would because even a stout arm will have a difficult time against the field these things produce. I don't know if that's true, but I'm going to find out Anyway, these things should be good to around 250°F if the designation is honest, which is better heat tolerance than the stock neos by a good margin. Price was $5.99/pair which seems like a bargain and, as I said above, service was first rate from the vendor. Anyone looking to do something crazy should DEFINITELY get some to play with as they're crazy-strong. Looks like I'll be making another Strapnut^TM

-john

PS: If anyone's interested, here's a link: Emovendo X-Mod neos

[Victor Poulin]

Thanks for the link John, I,m on it !!

[havlicek]

Cool Vic

I think you're going to be surprised shocked at these things. I've pretty much got a setup done for this. I had a strapnut cut and an endbell trimmed to fit, so all I had to do is figure out the shimming. The only shim stock I have is .007" and .003" and neither was enough, so I cut up another S7 and used the sides as shims. That leaves the airgap at something like .528" or something, maybe a little smaller If it seems ridiculous, I have some undersized lams here (an assortment between between .460" and .480") I can build an arm from for a little more breathing room. It was very difficult epoxying-in the magnets as they kept grabbing onto things and jumping out of my hand . I'll get some pictures up in a little while when the epoxy is cured enough to handle the setup.

-john

[havlicek]

OK...so I got the setup done and the airgap comes out to around .518" - .519", a little on the snug side for a regular .510" arm. So I have some .007" x .485" lams (pictured) I'll build a stack from and work from there. It was difficult just putting the shaft into the motor ...but I figure this one should get ball bearings on both ends just in case it works well.



-john

[MantaRay]

Well, I got the 1.99 Chinese Special motors in today..............Vic, As John said.............They just drop in a K&B Bobcat............Has a lot more grunt than the stock arm...But, Just like John said.....They need to be epoxied, tied and balanced.

[havlicek]

Cool Ray. To be fair, I really was just repeating what Allen had originally said as a way of confirming his info was pretty much spot-on. I bet that after balancing, that motor will be a great runner. I took one apart and got 85 turns of #29 wire on a short stack.

-john

[Victor Poulin]

Ray thanks for the info, I was hoping to hear that. I have a couple old K&B bobcat motors that I want to rebuild. I got my motors in todays mail so tomorrow I,ll start tearing into one.

John, I think using BBs on that one was prob a good idea. I have the feeling you'll be glad you did I don't think you even needed to shim those mags in that close . I,ve got a buddy that uses simalar Neos in Proslot D-can motors. The things have one hell of a gap, but they scream !! He,s using 518dia 38deg arms and like I said, he doesn't shim the mags at all. Not sure if they have any brakes or not though lol.

Vic

[havlicek]

We'll see Vic. I'll probably take the arm down to something like .475" or even .470". With a .518" hole, that will leave a pretty jumbo gap. I've got the stack built now and it's difficult to turn the arm in the setup. Heck...it's really difficult just to place the arm in the setup. This is uncharted waters for me, although I guess it's something like a crude distant relative of the eurosports motors. I'll probably start off with a #26 wind and see if it turns over

-john

[Alchemist]

Wow - John!

This new setup may be equivalent to "twin-turbo" horsepower - you think?!?!!!! It's exciting to see and hear stuff like this.

thank you John!!

Ernie

[havlicek]

Hi Ernie,

Honestly I don't know what to think about this.

-Is it possible to have too much magnet regardless of wind?

-Is it possible that any wind will produce too much heat for the setup?

-Is it possible that the motor will draw too much current for any reasonable power source?

-Will it just sit there when power is applied and self-immolate (barbeque)?

The way I look at it (and this could be entirely off base), it doesn't make much sense to have strong magnets and then build a motor with a gigantic airgap when weaker magnets with a tight airgap might work as well or better. In other words, these things (as strong as they are) may not be particularly useful for slot cars...OR...they might be cool??? Vic mentions someone using these things unshimmed in a 36D setup. There would obviously be something of a weight advantage...but a set of Arcos makes a 36D a pretty cool motor.

-john

[Alchemist]

Hi John,

The way I look at it (and this could be entirely off base), it doesn't make much sense to have strong magnets and then build a motor with a gigantic airgap when weaker magnets with a tight airgap might work as well or better.

From my little knowledge that I've acquired from this thread - I would agree. It's like building a twin turbo big block and putting a "rev limiter" on it!

Ernie

[Prof. Fate]

Hi

With too much magnet for a wind/stack combo, one can indeed have a slower motor. The short version is that the better the field/saturation, the hotter wind you can run with success.

Fate

[Victor Poulin]

Rocky,
I understand what your getting at, but how does one know when enough is enough or to much? I do remember, that Monty O. had told me sometime ago that in some cases weeker mags worked better in some motors. I found this out myself first hand. I had built a 16-D set up. I found some mags that I had that had a very strong gauss reading. I set the motor up using a stock low timed Parma arm. When I powered it up, I wasn't really happy with the way it performed. Long story short, Monty told me to swap out the mags with a weeker set, and sure enough, the motor came to life, and ran like a well built 16-d should. So yes, I understend what you are getting at.

Vic

[havlicek]

OK, I have a little better idea what I'm dealing with. I decided to build an arm with a .505" diameter and cast all caution to the wind. Stack length is .300" and the wind is a #26awg. I can confirm that the motor sounds impressive as all get out at 5.5V, but didn't have the nerve to up the test voltage. When I remove a power lead, the motor stops dead with no wind-down at all. While the motor does get a little warm at this voltage, but it's not nearly so warm as I would expect for it's current draw of over 7 amps Part of the reason I didn't raise the voltage is that the arm didn't balance out so well and I was a little concerned about stuff flying around the room. I think the setup is a keeper for now, and I'll work up an arm just under .500" and go to a #25 for test #2. Anyway, here's Super Strapnut 1 as it stands now:



This has been a lot of fun and I'm already looking forward to doing the next arm for this...er...thing!

-john