Rivarossi motor retrofit project (and request for help)

[mmagliaro]

Folks, I'm tilting at windmills again...

I have had some special neodymium ring-shaped magnets manufactured to exactly fit into the Rivarossi cans.  My plan is to find some bulk motors with the correct size armature that would drop in to the RR can, along with real magnets to replace the rubber piece of junk that is in there, and have a sort of "super upgrade" kit for these things.

I know they are old-school engines.  But I think a lot of people still have them, many with dead melted motors, and would love to put them back on the track again if only there was a simple screw-in replacement motor that didn't require frame grinding and scratch-kit-bash-nerding to get in there.

I found some 3-pole motors with heavy skew windings that look a lot like the one used in the LL 0-8-0, which was an excellent running motor.  I'm trying to get those to fit into the cans now.  But they are just a hair too long and it's taking a lot of experimentation (and wrecked cans and armatures) to get a process honed to do it.

SO... I am making a plea.  If any of you have old, dead Rivarossi can motors from the 1970s era Atlas/Rivarossi steam locos, and would not mind sending them off to be used as guinea pigs for my experiments, I could sure use them.  Of course I will pay your postage.  Please PM me if you have any you are willing to part with.

[Lemosteam]

You need to have a magnet upgrade for the old atlas 0-4-0 motor.  You'd sell a million.  Riiight.

[mmagliaro]

You need to have a magnet upgrade for the old atlas 0-4-0 motor.  You'd sell a million.  Riiight.

Actually... it is the same motor used in the 4-6-2 and 0-8-0.  The only difference is that it has a worm mounted directly on the shaft instead of using that fork thing. 
Million?  Heh.   Well, no.  But I bet there are some sad 0-4-0 owners out there who would like a working motor.

[peteski]

Max,  you actually had those made for you?!  You sly dog! 
Would you sell few of them to me?

[u18b]

You need to have a magnet upgrade for the old atlas 0-4-0 motor.  You'd sell a million.  Riiight.

I'd be up for one or two.
I have a pair of great Atlas 0-4-0 that I added DCC.  Great runners.... so far.  Until that old motor burns out.

[mmagliaro]

Max,  you actually had those made for you?!  You sly dog! 
Would you sell few of them to me?

Indeed.  I have not received them yet.  First, I found a magnet manufacturer in the US who made some for me (still waiting on them), and then I found a place in China through Alibaba who has made some and those should be here tomorrow.  This will be an interesting comparison of quality.  The US made ones cost 10x as much as the ones from China.
Also... we don't even know if they will work yet, or if something was screwed up on the measurements (me) or manufacturing (them) that would cause them to not actually fit in the can and clear the armature.   I'm wondering how much fun it will be to get one of those OUT of the can if I slip it in and then want to remove it, or how difficult it might be to put the armature in and get it all the way down into the bearing without the magnet pulling it fast against one side.  A Neodymium ring like that could have ferocious grip.  I suppose some styrene positioning shims slipped in between the arm and the magnets would be a good idea while I slide it in.

[peteski]

I am impressed Max!  I just hope and pray that they are magnetized properly!
And yes, care will have to be taken when handling them, and when installing the armature. 

[mmagliaro]

I am impressed Max!  I just hope and pray that they are magnetized properly!
And yes, care will have to be taken when handling them, and when installing the armature. 

I discussed the magnetization with both manufacturers.  They will be "diametrically polarized", which should be just the way they need to be for an electric motor (and just like that rubber ring in the RR motors).... halfway around the cylinder is "N" and the other half is "S".  That's how the rubber one is too.  If you take one out and unroll it, and then test it with another magnet, you will find starting at one end, it will attract your magnet, and then just as you reach the middle, the polarity flips and it repels you magnet the rest of the way to the other end.

There are plenty of things that can go wrong with this.  Might not fit.  Armatures might not work.  Or the whole thing might work and just be lousy (or just as lousy as the original).  That's why they call it "R&D"   

[peteski]

I discussed the magnetization with both manufacturers.  They will be "diametrically polarized", which should be just the way they need to be for an electric motor (and just like that rubber ring in the RR motors).... halfway around the cylinder is "N" and the other half is "S".  That's how the rubber one is too.  If you take one out and unroll it, and then test it with another magnet, you will find starting at one end, it will attract your magnet, and then just as you reach the middle, the polarity flips and it repels you magnet the rest of the way to the other end.

There are plenty of things that can go wrong with this.  Might not fit.  Armatures might not work.  Or the whole thing might work and just be lousy (or just as lousy as the original).  That's why they call it "R&D"   

That does sound like the polarization is correct.  I do have a handy test card that shows magnetic fields of magnets. I got it years ago somewhere and it works great.  Similar to using iron shavings, but they are contained in a flat sheet of plastic.

I hope that you didn't invest your life's savings into this venture (and hopefully designed the magnet a bit smaller than the average inside diameter of those Rivarossi motors)! 

[mmagliaro]

That does sound like the polarization is correct.  I do have a handy test card that shows magnetic fields of magnets. I got it years ago somewhere and it works great.  Similar to using iron shavings, but they are contained in a flat sheet of plastic.

I hope that you didn't invest your life's savings into this venture (and hopefully designed the magnet a bit smaller than the average inside diameter of those Rivarossi motors)! 

Oh no... It was not pennies, but it wasn't thousands either.  If it all goes bust, I will just chalk it up to a very fascinating and "slightly expensive" mistake.

[Lemosteam]

Indeed.  I have not received them yet.  First, I found a magnet manufacturer in the US who made some for me (still waiting on them), and then I found a place in China through Alibaba who has made some and those should be here tomorrow.  This will be an interesting comparison of quality.  The US made ones cost 10x as much as the ones from China.
Also... we don't even know if they will work yet, or if something was screwed up on the measurements (me) or manufacturing (them) that would cause them to not actually fit in the can and clear the armature.   I'm wondering how much fun it will be to get one of those OUT of the can if I slip it in and then want to remove it, or how difficult it might be to put the armature in and get it all the way down into the bearing without the magnet pulling it fast against one side.  A Neodymium ring like that could have ferocious grip.  I suppose some styrene positioning shims slipped in between the arm and the magnets would be a good idea while I slide it in.

You could use tome thin wall brass or aluminum tubing to keep the armature centered all the way down, and then pull the tube out.

And yes, I'd be in for three or four sets of magnets if this all pans out.

Max- the Mad Model Motor Manufacturer, Picking up where the Motorman left off?