27 replies to this topic

[havlicek]

Recently seeing some of Don Seigel's posts, I got inspired to do one (pretty much) the way we did it when I was a kid.  Those were the days when a couple of hours...a couple of nights after homework during the week spent "improving" a Mabuchi bought with my paper route money, meant I could hit the local raceway (whatever it was?) and either burn up the motor...or brag to my buddies about what a rocket it was (relatively speaking).  So...

 

Here's the "stuff" I started with:

Nothing at all special.  Some sort of Mabuchi (?) can, a set of stock Mabuchi 16D magnets, an FT16D end bell (I'm using the bushing only), a clean Tradeship Ft16D end bell, and the stock arm (which isn't a Mabuchi, but I think a Johnson judging by the plastic insulators and tail spacer...same junk).  So it's "off to the races" (figuratively speaking that is)!

 

First order of business was to clean out the can (the old magnets had been epoxied-in and it was a mess.  Also, the bushing had to go and a quick "have at it"  with the Dremel and a round nose grinding stone from the inside removes the lip and out comes the bushing.

 

 

Afterwards, the can bushing was replaced with an extra end bell bushing from the white end bell (MUCH BETTER), making SURE it was aligned with the end bell bushing.  The areas of the can where the tabs had broken off were ground to a radius, so the can didn't look like it was rescued from the garbage, the can was drilled for end bell retainer screws, and then sanded/stripped of it's chrome...OOOOO, it looks better already!

 

 

Moving forward, the stock magnets (as weak as they are) CAN be part of a total motor "package" that will definitely perform better than the stock motor by a wide margin.  Here, I'm using a super clean pair and will also be installing a pair of .004" steel shims.  It doesn't sound like much, but the strength of the field exerted on the arm increases exponentially as the distance between the arm and the magnets is closed/tightened.  .004" per side (.008" total) will beef things up noticeably.

 

Also, here the can has been primed (it'll get wet-sanded before top-coating), the shims have been fabricated, the end bell hardware has been cleaned of a pretty fair amount of corrosion, and the can just needs top-coating (I'll use "Hammered Green"...I'm on a kick with that color lately, it's ...er...cool beans).

 

 

For the arm, the stock stack was stripped and the plastic insulators removed, after which I cut a pair of spacers for the com and tail.  I won't be using the stock commutator because I just can't bear using that garbage with all the work involved in even a "simple build" like this one.  Instead, I'll be using a com from a modern "D" motor arm...it's nearly the same diameter and functionally equivalent, plus it will last better.  A quick trip to the powder coating department (er...my garage    ), and it'll be ready for winding.  Since I'm not doing any extra protection on the end bell, this motor will get a #30 wind, which will be a good match for the stock magnets and hardware...stay tuned.

 

-john

[SlotStox#53]

  watching this "old Skool" build is every bit as exciting & interesting as your Wild motors John Watching with interest & taking notes.

 

On the Comm side of things could you also use the old tradeship style 16D comm that's available ?

[havlicek]

Hi Paul,

 

     Yes, the Tradeship coms are fine for mild winds...certainly better than stock, and their extra height makes radiusing/clearancing the end bell unnecessary.  Best to use a good silver solder for the com connections...and never use acid (of course!) for any electrical connections.

 

-john

[SlotStox#53]

Thanks John Got a spare Tradeship endbell with hardware sitting around & a whole bunch of those late Hong Kong FT16D motors too so with all the info & bits got plenty of stuff to have a play with

[Bill from NH]

The comm connections could be a place to use a liquid rosin flux like Sears & other places sell. Even Radio Shack now sells both a liquid & a paste rosin flux. Slick 7 sells a high temp. silver solder, that might be desirable.

[Gator Bob]

Nice choices... for a paper boy

 

Well John ... it's not your favorite K&B.

 

But I'll go with what KC &   said (and still does).

[havlicek]

Bill...I *think* that the paste might be better because you can stick a teensy bit on there and it stays put, but whatever works for everyone as long as it's not acid!  Honestly, we always just used regular 60/40 and it seemed OK on the mild winds we most often did, but a 4% silver solder is probably better.

 

Paul, those later Hong Kong motors are great for this stuff, and they come up on eBay for cheap.

 

Bob, if it were a K&B, I'd try and leave the original paint on there...ESPECIALLY if it had the original sticker!    I haven't found a rattle can yellow that gets hard enough to stay put on motors, in fact, all the light colors don't seem to cure as hard as the darker ones and the various textured and "hammered" finish ones do.

 

...anywho, I got the arm all wound and balanced (razor blades...remember, this is sort of supposed to be like we did it back then!) and it's a simple matter to stick everything back together and fire her up!

 

-john 

[Gator Bob]

John,

 

Do you weld right through the wire insulation or still have to carefully remove it as is done with soldering?

 

The Johnson 222 (Hong Kong) has a great brush hood set-up....   

Bucket list item - I'm going to make a 'King Kong' version out of a blown one I have here.  

[ossamoto]

very educational, John. I built some back in the late 60s and early 70s, didnt last long and ive forgotten more than I remember. You need to do a cd disc(like Mike Steube did for scratchbuilding frames!)

[havlicek]

 

John,

 

Do you weld right through the wire insulation or still have to carefully remove it as is done with soldering?

On this motor, I soldered the com, but no matter how I do those connections, I always scrape off the insulation first.  Even a little insulation staying on there...or some carbon from burning it, will change the resistance of a pole and the modern insulation is much tougher than the old stuff you could solder through without removing it first.

 

 

 

very educational, John. I built some back in the late 60s and early 70s, didnt last long and ive forgotten more than I remember. You need to do a cd disc(like Mike Steube did for scratchbuilding frames!) 

 

Well Gary, it doesn't take much to wind up a motor...just sitting down and doing it is all.  Things get better as you do more.  I can't see doing a video on this stuff with all the information I've posted here over the years, but I'm always happy to answer questions.

 

-john

[JimF]

Seems like a small thing but nice radiusing work on the shims. The corners look perfectly matched and the magnet radius is smooth and even. Every bit as good as the manufactured ones from back in the day. (probably better)

[havlicek]

...and all done.  It's pretty much a 1 amp motor (maybe a bit under) and should settle even lower after some break in, but a VERY solid runner that should be at home in any period car.  Plenty of grunt out of so little

 

 

-john

[SlotStox#53]

You're definitely right John, that would look perfect in a period type car

That really looks one super sweet old skool build looks like your own wound brush springs too .

[hiline2]

Is it going to make it over to Ebay?

[havlicek]

Thanks for looking guys.

 

 

 

You're definitely right John, that would look perfect in a period type car   

 

I think it was a Honda or something, but there was an old F1 car I used to love for stuff like this.

 

 

 

Is it going to make it over to Ebay?

 

 

Probably Paul.  Things have slowed down with the warm weather and I have a bunch of motors both done and in progress that I thought I might hang onto until the fall.  Maybe I'll put up a few right here???

 

-john

[Tom Eatherly]

John,

I'm not a motor guy any longer, But, have looked at some of your builds. Very impressive. But, this last one is so COOL!

With out doubt, a throw back type of build. Thank you.

[havlicek]

Well thank YOU Tom.  Of course when I was a kid they didn't come out as neat and there was only a 50/50 chance they wouldn't smoke, but we didn't use upgraded magnets, end bell bullet proofing and better coms.  

 

-john

[slotbaker]

Looks great John.

 

How many turns of #30 did you put on?

[Bill from NH]

Lots of interest in this motor John.

[havlicek]

Looks great John.

 

How many turns of #30 did you put on?

 

Hi Steve,

 

     I usually go from 65-70 turns on a #30 wind.  This one is 70 turns, and it's a little tight on the Mabuchi blank.  I could probably get as much as 75 turns on there without whipping out the old popsickle stick, but I didn't see any reason to go that route on the motor.  I'll often do #31 wire on a stock Mabuchi FT16D setup, but #30 wire is fairly safe  and makes for a solid motor.

 

-john

[rodslot53]

Hi John,

I am building up a Mura C-can motor to use in the Tottenham  class in the UKRRA. The can was not in the best of condition, so have taken it back to bare metal. Interested that you have repainted the can in your rebuild, what type of paint have you used, I assume enamel, or can you use acrylic paint. The reason I ask is that I will use Koford epoxy to fix the magnets into the can, and this requires to be cured in the oven, so would that effect the paint on the can?

Rod. 

[Pablo]

If I may, acrylics won't cut it on a motor - enamels or lacquers are the way to go.

Best to bake your magnet epoxy before painting the can. Will the baking melt existing paint ?  It might.

I'm sure John will also point out, for safety's sake, don't use the same oven you use to prepare foods, and always bake outdoors or in a well ventilated area.

[havlicek]

What Pablo said (of course)!  I always use enamel and except for "white", the baking doesn't harm the paint at all.  At around the 275-300F heat I use for both speed curing epoxy and baking the paint, white can turn a little yellow.  Most "regular" spray enamel is fine at these temps and it can help cure the paint, although it will feel a little soft when it first comes out of the oven.  What I haven't tried yet is regular automotive spray paint...just because I keep forgetting , but I *think* it might cure harder than regular spray enamel like "Rustoleum" brand.  I do have a can of a nice blue for engine blocks that says it's good to 500F that I want to try also.  The bottom line is that I haven't found any regular spray enamels that get nearly as hard as what came on the old Mabuchi motors, probably because most of the stuff in those that made them cure up so hard and durable have been outlawed out of concerns for the environment.  Of the Rustoleum products, their "Textured" and "Hammered" finishes seem to cure harder then their regular gloss paint, but I don;t if any of those are available over there?  For all I know, you guys may have better stuff than we do

 

-john

[SlotStox#53]

John, over in the UK , or at least down in the London area we have basically the Rustoleum equivalent , it's called "Hammerite" comes in many colors and both smooth & "hammered" texture, cures/stops rust etc...  As to whether it's the exact same stuff just different branding for either side of the pond or separate brands I don't know..

 

Smells exactly the same

[havlicek]