Just thought I’d share some ways to help improve the motors in your engines.[:D]
I’d like to start with some ways of switching out old magnets with newer, stronger ones. Stronger magnets will increase power, while reducing speed and current draw in most cases. All magnets used here are neodymium, which is the strongest type of magnet in the world, and were purchased from http://www.kjmagnetics.com/.
First up is an easy one.
Athearn’s old silver motors are good runners, but they’re very weak too. Changing out the old magnet with a stack of five new ones is pretty easy.
I found that 1/4"x1/4"x1/8" magnets were the best fit here, but as you can see, they were just slightly too long, so I had to bend the ends of the plates a little to make the motor go back together. With the stronger magnets, my little Hustler now has a lower starting voltage, draws less current, and has noticably higher power.[:D]
Next up is the Mantua/Tyco MU-2 power trucks.
The one shown here is actually Roco’s plastic MU-2 clone, made for Tyco in the mid 70s. A 1/2" cube fit well in place of the old magnet, but the steel rivet has to be taken out first. I got the rivet out by drilling out the flared end of it. The steel plates that wrap
I was looking at a burned-out Athearn gold can motor last night, and it looks like I may be able to fit some stronger magnets in it too.[:D] With the stock magnets, the gold motors (at least the ones before the RTR line came out) have less torque than a Mabuchi motor of half the size, so I’m going to see about getting more magnets so I can experiment. If it’s a success, I’ll post the results.[:D]
I got some larger magnets for the Rivarossi motors, and the change was a success!
The new magnets are 1/2" x 1/4" x 1/8" thick, and fit the motor much better than the 3/16" cubes. All that has to be done to make them fit is to cut out some of the plastic endplate to clear the magnet, visible in the picture. Once the magnet is in, it should be glued in place to make sure it doesn’t slip into the armature. Not only was this easier than the cubes, but it was also much more effective. My 2-8-4’s speed dropped from 85 or 90 MPH to 70, and my 0-8-0 dropped from 120 to 105. Both engines draw 0.05 amps less at full speed. The torque is also much higher, so the motors are no longer under powered for the larger steam engines.
The Mantua PM-1 motor now has a new magnet that isn’t shattered, and it runs even better than it did with the shattered magnet.
The Athearn motor experiment was a total failure, so now I’ll have to look for some other use for all those 1/8" cubes.
Hello thanks Darth the rivarossis part helps out I have one that needs tuned up. How about something for my old Varneys ? I have 2 with the Lindsy drive 2 pulleys and a spring as a belt and it mounts to the rear truck. Thanks Frank
0-6-0, if your Varney trucks still have the open-frame motor, you can upgrade the power with a new neodymium magnet. All you have to do is measure the size of the magnet, and get one (or a stack) of the proper size. Just make sure it’s magnetized the right way, or the motor won’t run at all! As far as Lindsay drives, I don’t have any experience with them, but I’ve heard they’re an excellent design, so a simple cleaning and oiling should be enough to get them running again.
Pathfinder, yes, the Hustler is a little faster now. The motor actually runs at a lower RPM now, but it also now has the torque to really get it moving!
Hello Darth yes they are open frame motors they run but they are really slow. But that’s not a big deal . They don’t have the pulling power I think it should. They are kept clean . They are all metal f7a and one metal b unit that is not powered. It will pull 5 or so cars but if I put the b unit on it goes down to 2 cars. One was my dads from the 40s and we built it a year ago so the motor only has maybe 10 hours on it but it is 63 years or so old I would guess it would lose some power in that time. I will check out some new magnets and let you know how it works out. Or can I give the old magnets a recharge. Thanks Frank
Does it only have one powered truck? If so, you can increase pulling power by adding weight around, over, or near the powered truck. Also check to make sure the unpowered truck and dummy B unit are extremely free-rolling, because pulling or pushing stiff wheels is like dragging a hunk of lead around.
The old magnet may have lost some power, but I wouldn’t recommend recharging it yourself without a special tool. Can the armature turn freely? If not, check the brush tension, and make sure the bearings are oiled. You’d be surprised at how much noise and loss of power and speed can come from old, dry bearings.
I missed this post the first time around, Darth. I was trying to find replacement magnets for the Athearn gold motors with the right dimensions myself, but all crescent shaped neodymiums for can motors I’ve seen have been for undersized motors in that line of small XMOD RC cars.
BTW, I saw a Dyson commercial the other night for their small canister vacuum, and they were touting the power of the neodymium magnet motor. Maybe James Dyson read this thread. [swg]
Darth Santa Fe this is great info but I have a few questions.
I want to try replacing the magnet on some TYCO/Mantua PM1 motors so here goes.
How do I determine the north and south poles?
Are the north and south poles at the top and bottom of magnet where the frame is or are they at the end of the motor and on the inside where the armature is.
I think you used a 1/2 inch cube for yours, how did you know how to correctly orient your cube?
Did you use N42 or N52 magnets and what would be the difference using the different strengthens? Which strength would give better top end, use less power, etc.
I used the old manget as a reference to determine the poles. The opposite poles attract eachother, so when the magnets get stuck together, you know their orientation is the same. To make it easier, the old magnet should be marked before taking it out, and then the new magnet can be marked the same way once the poles are figured out.
The poles are at the top and bottom. The magnetism goes through the steel plates that wrap around the armature, so the magnet is in a way surrounding the armature like in a can motor.
I did use a 1/2" cube for the Mantua/Tyco motor. See the first part of my reply to know how to get the proper pole orientation.
I used N42 magnets. The N52 magnets would give even more power than the N42 and further lower the current draw, but they cost around 25% more. One thing to keep in mind as far as speed goes is that the stronger the magnet is, the lower the speed is.
I would personally do this before upgrading to a Helix Humper or Yard Bird motor. The Mantua motor is very well engineered. And with the stronger magnet, it runs about as well as a can motor. It’s also only about 1/10th of the cost, since the 1/2" cube with a 3/16" hole is only $2.90.
And I’m sure I mentioned before, but never let the 1/2" cubes get close enough that they attract eachother together! When I let the two neodymium cubes go together, the force was so strong that one of them shattered!
I’ve never checked the speed on my Hustler but back in the day it had to do 150 Scale Miles Per Hour. That thing just flew around my layout and at times would become airborne going around my typical 18" radius curves. But I digress…[swg]
One thing I’ve observed is that when using two rows of magnets, as in your Rivarossi ball bearing motor, the two rows have to be oriented NN - SS, since they are acting as a single magnet. Otherwise they will attract and cancel each other out, and any magnetic force in the pole pieces of the motor will be residual and weak.
Here’s a shot of a PM-1 motor with twin rows of neodymiums. The individual magnets are stacked normally with opposite poles attracting, but the stacks are positioned in the motor with the same poles at the top and bottom.
I tried this on a TYCO Rodgers 4-6-0 using 1/2 inch cubes, they fit great. I first tired a NEO 42 then tried a NEO 52. The performance is definitely better than the old magnets but not good enough in my opinion.
I found the top speed to be about the same with either but the NEO 52 seemed to have a little smoother power curve at the top end. I have not measuring equipment to measure the top speed so I just counted how many seconds the train took to make a lap around my circular test track and both seemed about the same.
I have one of the Rodgers 4-6-0 engines that I previously put a helix humper can motor in and have to say that the can motor performs much better. It has a much better speed range, starting off at a much lower throttle and easing up to top speed through the range. The top speed seemed comparable to the NEO modified motors.
I play with magnets in my slot car motors all the time. Here is something that you’ve probably never heard of before. I break in all of my slot car motors by running it for 15 minutes at varying speed using a transformer in a cup of water with a drop of dish soap in it. The dirt and crap that comes out of it is amazing. I then flush it with this stuff called Voodoo Juice, oil the bearings and install the motor in the car. The performance of the motor is improved dramatically. This is an old slot car trick I used for years. I’ve never tried it on a locomotive motor but they are basically the same.
There are ways to re-charge magnets on your own but I don’t know how feasible it would really be. A Bing search resulted in several ways, but a search on eHow resulted in this link: http://www.ehow.com/how_6751013_recharge-magnets.html.
Slot racing centers in the old days had equipment to re-energize magnets since the magnets needed it after a night racing due mainly to the effects of the heat, besides the car taking a beating. You could check to see if there is a slot racing center or LHS that could re-charge magnets. The advantage would be maintaining the same magnet shape and armature clearances.
