3573 replies to this topic

[havlicek]

One more little detail needed to be dealt with on the endbell. If you look at the thing, the spring tabs sit directly in line with or even behind the brush tubes which would have made installing the springs difficult as well as causing the long arm of the spring to have to bend around the brush tube/heat sink. So I removed the spring tabs and fashioned a pair of washers with tabs on them that will extend beyond the brush tubes out of some spare brass. I also cleaned-up my sloppy soldering of the hoods while I was at it. NOW I can move on ...I think



-john

[Slotgeezer]

Very nice, John...
Using 36D brush hoods w/ a 16D endbell is a great idea... & heating everything to get it to "self-align" is another great idea... I soldered MY share of 16D brush hoods, back in the day, THAT'S for sure!
Love the home-made spring tabs... Great idea... Now I've learned how to "save" those 36D brush hoods that I've broken the tabs on... Thanks!

Onward!


Jeff Easterly

[BoomerDog]

Hi, John,

This entire string has been ultra enlightening and your information is excellent. I'm still reading and re-reading these entries. I've got more of this style can and end bell along with well over 20 era arms. Some old 12's, balanced X-12's and 15's. I can't tell you how many times I was just going to chuck the whole mess, but something kept telling me not to.....lol

I'd be more than happy to send one to you for a project (like you need another one )....keep up the great work and I'll keep reading.

[Maximo]

John,

Totally fascinating! I am mesmerized!!!

-Max

[havlicek]

Love the home-made spring tabs... Great idea... Now I've learned how to "save" those 36D brush hoods that I've broken the tabs on... Thanks!

Oh yeah Jeff. I've repaired enough hoods with broken tabs that it felt really wrong breaking them off on purpose Still, it would have been just as easy to set the brush tubes in further and then grinded them in there. I was thinking that it would somehow be better to have longer tubes and as usually happens when I think too much, I start creating extra work for no apparent reason.

I've got more of this style can and end bell along with well over 20 era arms. Some old 12's, balanced X-12's and 15's. I can't tell you how many times I was just going to chuck the whole mess, but something kept telling me not to.....lol

I'd be more than happy to send one to you for a project (like you need another one )....keep up the great work and I'll keep reading.

Hi Steve,

For sure you can toss whatever you don't want my way I can only salvage coms from the old arms (which is something anyway!), the cans and endbells I can always use.

Hi David,

I'm glad you like it so far...it will only get better from here on out

-john

[havlicek]

More progress on the "NHB" motor for Maximo. First order of business is to get the magnet part of the equation sorted. David had sent me what look like they might be a pair of magnets from a B motor, along with a Champion shim (the kind that automatically off-centers the magnets if you don't add top shims ). These are fairly thick magnets and they were way beyond what the setup would accomodate with the .020" Champion shim, they're also a lousy fit for the can and/or the shim. I cut a pair of shims out of .007" shim stock and they were still too thick and I would have had to screw around some to make them fit properly.


I have several pairs of D can magnets here and one of them is thicker than the others and is a really nice fit for the can. What I really liked about these also is that the top and bottom edges are "back-cut" at an angle. By fashioning a pair of thicker than usual magnet clips, that "back-cut" forces the magnets to center themselves (even though they pretty much fit dead-on anyway). On my meter, they measure almost exactly the same as the ones David sent me and with being a much better fit...they got the nod. Here they are in the can:


Now that the whole setup is complete, it was time to get going on the arm blank. As I had mentioned earlier, I decided to go with a .007" blank and I have one here I got as a trade for a bunch of Duralco epoxy from Doug Azary. The shaft wasn't that straight and the arm blank was for can drive, so I replaced the shaft with a 2mm drill blank and positioned the stack for endbell drive. Of course as luck would have it, the shaft was ever-so-slightly thick for the bearings, so I had to polish it down maybe a few ten-thousandths. That's a little tedious as you don't want to go so far as to have a sloppy fit as that would defeat the whole purpose here. So you have to go really easy until the arm is able to just slide in to the can and endbell with a little pressure.

For a com, I chose one I salvaged from a Mura arm. A quality bulletproof com for a motor like this seems prudent, and I had already taken care to be sure there was enough clearance in the endbell between the brush tubes for the fatter com without having to radius them out. The blank measures just over .510" after rough polishing and it's all spaced to center in the field of the motor. Here it is with one of the 2mm drill blanks unpolished:


After I set the timing and epoxy the com and spacers in place, I can start winding!

-john

[havlicek]

The NHB motor's arm is wound, tied, epoxied and balanced:


In it's new home:


Just a couple of details to take care of...shunts, spring insulation, some more break-in and maybe try some different weight springs and such, but it's a really strong runner for sure Runs very smooth and draws about 3 amps on the button without getting too warm.

-john

[Maximo]

Beautiful work!

-Max

[Slotgeezer]

Yeowser, Boss!

21 turn 25?... YEAH, BUDDY!!!!

Great job, John....

I know I'd be happy... Very nicely done, & good lookin' to boot!

C-ya!


Jeff Easterly

[havlicek]

Thanks again guys.

David, the new avatar works for me The NHB motor is almost done and I should be getting it (and the others) out to you in tomorrow's mail.

Jeff , that's my favorite #25 wind and I know it's right on the edge for a motor like this, but I don't think this thing is going to be raced heavily and if run with care it should hold up just fine Of course, the heart of the matter is a quality blank, and the old Mura I got from Doug is what makes the thing. It probably would have run fine with a Tradeship or similar blank, but those old .007" Muras are just great. I don't have any scientific proof...but I think they account for a significant increase in performance. Heck, I'm not even sure the blank was .007"...it might have been .005" as the lams looked awfully paper-thin.

Anyway, here's a rundown on the last niggling details. I definitely needed to install shunts on this thing as you could tell the motor was starving for power a little. Problem is that none of the springs I have (and I have a decent collection) has a short arm long enough to get past the vertical groove in the brush to secure a shunt there While 36D springs would surely be long enough...I don't have any, and those are light...probably too light for this motor. So now (thanks to Don H.) I have the option of winding my own springs and that's what I did. While I was at it, I made them a bit heavier than the springs I had tested the motor with. So now this thing is a solid 4 amp motor that whistles like the theme from the Andy Griffith show It should be a real handful in a lightweight inline thingy, but a few laps at a time should prove pretty exciting. I'll post one more completed picture later today before I box it up Use the force wisely Luke...er...Maximo

-john

[havlicek]

NHB completed and mostly broken-in:


As per above, the motor is solidly at 4 amps now after a bit of warm-up, but still seems reasonable for casual running. I wonder if Mr Mabuchi is aware of what people are still doing to his old motors

-john

[Slotgeezer]

..... I wonder if Mr Mabuchi is aware of what people are still doing to his old motors .....

-john

Oh, I'm certain that he's somewhere, up in the ether, screaming....

WHAT THE SAM HILL DID YOU DO?! ... WATCH OUT!!! ... IT'S GONNA BLOW!!!

Great job, John.... Awesome build!


Jeff Easterly

[Maximo]

John,

Thank you greatly for the incredible effort that you have put into this little NHB jewel!

Proud as I am I had to make it my new avatar!

I look forward to the arrival home of this motor and the other little cousins as well.

This baby is now going to require a special thingie to contain it!

"The force be with me"

-Max

[havlicek]

Hi David,

The pleasure in building this motor for you was all mine and I hope you have as much fun running it as I had building it. The box with the NHB and the other four will go out back to you tomorrow morning. Enjoy! (this motor will "dim the lights in Fresno"...no small accomplishment since I see you live in Texas)


Hi Jeff,

As always, thanks for looking in!
-john

[Maximo]

John,

This NHB motor might be too pretty now to run and instead will get a locked glass case in the new MAXIMO SLOT CAR MUSEUM!

Offical announcements to come!

Vroom - Vroon - Vrooom!!!

-Max

[havlicek]

Hi David,

I'm sorta torn on that. While I'm stoked, honored and flattered (!), I'd also like to hear that:

a)It spun the tires
b)You had to borrow a controller with a choke
c)The body softened right over the motor
d)...all of the above

...

Most of all, I just hope you get enjoyment from the thing!

-john

[Kim Lander]

John,
Once again I am very impressed with youre work, very detailed....what kind of magnets are you useing in your rebuilds....I may have some lying around on the bench calling your name...also other stuff that you may can use , ya never know, after 45 years things accumulate. Keep up the good work...Kim

[Maximo]

John,

Don't worry, the beautiful NHB motor is going to get the royal treatment. No that doesn't mean that I am sending it to
Kingie of Thingie Edo-san, but rather in a new surprise project car to-be-announced in the Thingie section!

Stay tuned.....!

-Max

[havlicek]

John,
Once again I am very impressed with youre work, very detailed....what kind of magnets are you useing in your rebuilds....I may have some lying around on the bench calling your name...also other stuff that you may can use , ya never know, after 45 years things accumulate. Keep up the good work...Kim

Hi Kim and thanks,

What I do is only a rough approximation of what some extraordinarily talented and knowledgeable people did routinely years ago. Most anyone with determination could do what I do or better if they'd give it a try. Still...thanks for the encouraging words

On the magnet thing, there's a bunch of vintage or modern magnets that are appropriate for the motors and mostly I just use:

1)What fits the setup best
2)A type of magnet that can be zapped
3)Magnets that are of a minimum strength for the type of arm

I don't use multi-segment magnets, but I don't doubt that some of my arms have wound up in motors with those. Modern D can magnets are generally as strong or even a little stronger than good aftermarket period magnets and are relatively inexpensive. Because they're pretty much in line strengthwise with what was available, I think they're entirely appropriate for a lot of vintage mnotors when the good old stuff isn't available. Arcos, Versitecs and Muras from the period are all good magnets, but can be more difficult to get and I think it weighs heavily in the modern magnets favor if their availability and price makes it easier for people to have a vintage-motored car in their collection.

Of course, if I'm doing a modern motor like the SCX RX 42/42B and making it look like a vintage one or just rewinding it like those I've done for Ed Miller, the magnets that come with the motor are great as-is. Same goes with the old Mura B and C motors...you can generally just rewind those, clean them up and straighten-out the endbell hardware and have a screamer of a motor that's 100% vintage...including the magnets.

-john

[Alchemist]

John,

What a work of art - SERIOUSLY!!!!! Thanks for sharing John.

Ernie

[havlicek]

...awww go on Ernie (thanks)

-john

[Maximo]

John,

I received this NHB motor today and after examining it carefully I can only conclude that "it is a friggin piece of art"!
So masterfully configured that I am in total awe!

It will require a nice car eventually to contain it's magic!
I keep it under lock and key with 24-Hour Surrveilance cameras and mercyless guard dogs!

Thank you dear Sir!

-Max

[havlicek]

THANK YOU David...you made my day

-john

[havlicek]

...a bunch of nice vintage stuff just in to make 4 motors (2 16D and 2 26D) for a blogger. It will all have to wait a day or so till I can get to it, but I'm looking forward to this project. Nothing too crazy...one each of the 16D and 26D a bit on the warm side, and one each of them a little milder still.



-john

[Slotgeezer]

Nice stack of stuff, John...
Obviously, a serious hobbist!
The "Motor Ect." stuff... Anyone know a web address, so one could look at what they sell?
Take care, John... Thanks!


Jeff Easterly