36 replies to this topic

[Kim Lander]

John, that is one cool build.

[havlicek]

Thanks Kim.  These kinds of builds are about as far from practical or period correct as can be.  Similar at least in spirit to my several "two end bell Mabuchis".  I look at them as a fun experiment, working within the limitations of the offset magnet/laminated field pieces of these types of motor designs.  While the 5 pole arm would be better suited for model railroading, those can be wound for more suitability to slot cars, but 3-poles can go faster and start quicker, so I went that way here.  The original magnets in these motors are fairly weak, and offsetting them doesn't do much for them either, so stronger magnets are an obvious way to go if "correct" has gone out the window...as it often does with my little "projects".    I've always disliked the various brush arrangements on these things...whether the Pittman-style brush arms and external center spring, or even worse, the little round "pencil leads" with tiny coils as this one had, so going with a C can end bell seemed obvious, although that triggered a whole series of details that needed to be dealt with.

Nobody is more surprised than me at how well it seems to run.  Current draw is way on the low side from what I could tell by the brief spin I gave it, which is even more of a surprise.  With the arm unbalanced AND being able to "rattle" back and forth because of no arm-spacing/centering, current draw should drop even more when the final assembly is done.  ***It would have been a real bummer if it turned out to be a real dog after all the work that went into it, so I'm more than a little relieved! 

[Alchemist]

Hi John,

 

That is an Autobot "Transformer" motor, and a phenomenal one at that!

 

Simply awesome John!

 

As always, I appreciate your craftsmanship - and grateful that you share the project!

 

Thank you John!

 

Ernie

[havlicek]

Hi Ernie and thanks.  These things pretty much dictate themselves as far as the build details.  When you put the motor on one side of your bench and the end bell on the other and start figuring how to make them come together, things just proceed one step at a time with each step dictating the next step.  So, really the first decisions you make tend to be the most important.  Now that I know the motor will run fine, I can look forward to finishing it up.   If anything, it may even be a little on the "mild" side, but that's probably just because I'm used to seeing, hearing, feeling what a #25 in a can motor should be like.  With current draw on the decidedly low side, I figure I could have safely dropped the turn count for more revs, but with such a relatively heavy motor, I think favoring torque over revs is the way to go here.  Judging by the brief spin I gave it, I think this motor could safely go in a road racer as well as a drag car.  Interesting!

[Jay Guard]

Definitely a "Frankenmotor" Herr Doktor Frankenchk, but beautiful nonetheless.

[havlicek]

Thanks Jay...sometimes it's fun to just go where the motor takes you. 

[havlicek]

I figured I may as well add a "post script" here.  The arm came back from grind/balance yesterday, and I was eager to get my grubby mitts on this "thing" to see what's what.  

*First the bad...after being put aside while waiting for final assembly, there was a good amount of rust on the field laminations.  I did my gosh-darndest to be careful and thorough about bathing and scrubbing the lams in baking soda, but there was apparently more to do.  So before assembling the motor I had some more cleaning-up to take care of.

*The arm came back with far less balancing than I thought it might need, since building the arm involved sleeving the lams' ID down to 2mm.  

*Assembly here is a bit more fiddly than usual.  Spacing the arm in the field involved disassembling the rear end cap and the end bell adapter several times, because removing the end bell alone doesn't allow a big enough exit hole to remove the armature.  No big deal, but definitely more fiddling than usual.

*After that got done, the rest was E-Z and "normal".  A couple of brushes (*tested to be sure they were sliding nicely) and a set of springs.

The result was very gratifying!  The motor spins super smoothly, no doubt because of a good balance job, but also just the sheer mass here compared to a typical "can" type motor.  The motor IS fast, like way way faster than the basic padlock it started out as, but has a relatively "quiet" sound, probably because the armature is more open here than it would be in a can.  Current draw is not at all worrisome and the "openness" of the padlock design will probably make for very good cooling.  Just going by "feel", this motor doesn't at all seem like running it in a road car would be a problem.  Of course, gearing, chassis, body etc. will all be important, but they always are.

[Geary Carrier]

John how bout some snaps of this little gem so we can have a bit more inspiration...

[havlicek]

Here you go:

[Geary Carrier]

Thanks John, now I is inspired...

[havlicek]

Hmmm...this is like one of those times when you stand between two mirrors and see endless reflections...kinda sorta pretty much like in a way.    After all, it was your Mustang build that got me off my duff after staring at the padlock that had been sitting on my bench gathering dust for so long.

[Geary Carrier]

Watching your motor building got me winding again after 50 years so I'd posit that we are just doing what we love to do.

Besides hobby winding is just smoke and mirrors, or is it...