Just thought I'd share some ways to help improve the motors in your engines.
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.
Next up is the Mantua/Tyco MU-2 power trucks.
NOTE: Make sure your truck has the plastic mount, and NOT the steel-plate mount! The steel plate in older models is highly attracted to the magnet and will not allow the truck to turn!
Third up is Rivarossi's square motors.
Last is a Mantua PM-1 open-frame motor, which is what you'll find in most of their older steam engines. the process is basically the same as with the power truck, with the rivet being drilled out and a 1/2" cube in place of the old magnet. The magnet will fit better with a 3/16" hole going through the middle to make room for the rear bearing. With the new magnet, the motor's current draw decreased about 30%, the speed dropped a few thousand RPM, and the torque went up, I'd say, over 30%, making it strong enough for even Mantua's largest steam engines.
Now some tips on handling these magnets.1. Never let them snap together! The larger magnets can and will shatter eachother! For example:It's amazing that I even got the motor working with the magnet like that...2. Don't put them close to electronic devices, like computers, cell-phones, credit cards, etc, or the device can be damaged.3. Don't let your fingers get caught between two magnets, because you can get a really bad pinch if that happens!4. When making a larger magnet by stacking small ones (like a 1/4"x1/4"x5/8" thick from five 1/8" thick magnets), make sure the polarity is through the thickness, not the length or width. Also make sure you get the polarity on the same ends as the old magnet, or your motor will runs backwards.
Now for another way to make a motor run better.
Some motors have too much tension on the brushes, making them run tighter, which will bring up the current draw and increase wear.
For brushes with leaf springs (or similar, like the coil springs with extensions on Rivarossi motors), bend the springs back a little at a time, and make sure it's the same amount for both of them. Keep doing this until the motor is running as freely as possible without reducing brush-to-commutator electrical contact. If you bend them back too much, you'll know it pretty quickly based on the motor's performance, and have to re-tighten them until it's just right.
For brushes with coil springs (like Athearn's black or gold motors), cut away a little of the springs at a time. If too much is cut away, stretch the springs back out until the motor is running properly.
Well, that's all I've got for now. I hope all this helps out some of you guys who want better running engines.
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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.
0-6-0 wrote: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
Do the drives look something like this?Varney: http://hoseeker.net/assemblyexplosionvarney/varney2060kf31951pg2.jpg(I couldn't find a diagram with the spring-belt drive)Lindsay: http://hoseeker.net/lindsay/lindsay4wheelpowerdrive1949pg2.jpg
Do you have any pictures?
Hello Darth I do not have a photo of the motor but I did find a web site that did it is
www.redehaas.dds.nl/Varney.htm
hope this will help Thanks Frank
RJ
"Something hidden, Go and find it. Go and look behind the ranges, Something lost behind the ranges. Lost and waiting for you. Go." The Explorers - Rudyard Kipling
http://sweetwater-photography.com/
With the stronger magnets, my little Hustler now has a lower starting voltage, draws less current, and has noticably higher power." border="0" />
Faster too?
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.
miniwyo, here's a link to a topic posted a while ago on making Athearn motors quieter.http://cs.trains.com/forums/1143504/ShowPost.aspx
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
0-6-0 wrote: 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.
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.
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
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.
Nelson
Ex-Southern 385 Being Hoisted
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.
1. How do I determine the north and south poles?
2. 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.
3. I think you used a 1/2 inch cube for yours, how did you know how to correctly orient your cube?
4. 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.
5. How would this compare to using a can motor such as the Helix Humper http://www.alliancelink.com/alp/photos.htm or a D8130 from Yardbirb trains http://www.yardbirdtrains.com/YBMotorIndx.htm. I know both of these have flywheels so that helps a bit.
Please elaborate a bit for my sake and others who may read this.
Thanks.
Hi steamie,
1. 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.
2. 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.
3. 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.
4. 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.
5. 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!
Very nice write up. Thanks.
This helps a lot and should help anyone else who stumbles upon this thread.
I think I will try the N42 mags. If I can come across a spare motor cheap then maybe I could try a N52 also and compare them.
I will most likely update this thread with my results, but it may be a while.
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.......
Modeling HO Freelance Logging Railroad.
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 didn't pay attention to the original orientation, but it's easy enough to flip the magnets if it runs the wrong direction.
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.
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.
Just my thoughts.
The recharging method from eHow would be useless for old open frame motors, because the magnetic circuit -- consisting of an alnico magnet, the pole pieces, and the armature -- is capable of holding more of a magnetic charge than the magnet alone, which is why manufacturers magnetized the assembled motor, and why these motors lose a major portion of their power when disassembled. I have a copy of a 1972 MR article on how to build a re-magnetizer from the filter chokes in an old CRT TV, but neodymiums have made that unnecessary, unless you want to keep a vintage piece original.
The rare earth magnets I put into the Mantua PM-1 motor in the picture above are a big improvement, but the motor speed still isn't as consistent as a decent can motor.
I suppose every motor is different. My Mantua motor was improved quite a bit over what it was, and runs nearly as well as a quality can motor. When the old magnets do lose their charge, a new magnet is certainly cheaper than a new motor.
steamie 1. How do I determine the north and south poles?
Oh, that's easy. Just keep your eye out for Penguins.... if you spot 'em, you're at the South Pole. If, on the other hand, you find yourself being eaten by a Polar bear, you know you've located the North Pole.
John
(And if you're surrounded by Eskimos raising their fists and chanting... ask 'em how was I supposed to know those weren't really lemon-flavored snow cones...??? )
John,
Here's my compass. I mark the pole he sticks to with an "S."
Neo magnets have been used in slot cars for a while. What a great idea. I'll try on my Rivarossi Big Six. One thing, if you put them too close to the armature, they will probably use more amps. As I recall if you increase the airgap to a point, they will run faster.
Funny one!
Actually I used a good quality bar magnet that was marked N and S on the respective poles. I then labeled the poles of the motor and the poles of the new NEO magnets to make installation easy, no guessing.
I did not think much about the air gap. I will have to experiment a bit with increasing the air gap to see if that creates an improvement. I probably have the magnets to close to the armature. Original Mantua motors had a good sized air gap between the magnet and the armature.
If that works better I will try to take some picks to post.
Been working more on new magnets. I've done a few since my last update, but I'll just give one tonight.
The conversion is a Mantua MU-1 power truck, used in the metal Shark Nose and Talgo locomotive. A new magnet is practically a requirement to make it run well, since the old magnet is very weak and can barely move a load. The steel truck mounting plate used in the earlier metal Sharks makes the conversion more difficult, but it should be just like an MU-2 power truck for the rest. Due to a smaller amount of room for a larger magnet, I used a stack of four 3/8"x3/8"x1/8" magnets (could've used 1/4" thick magnets, but I didn't see them when I ordered). I suppose if some filing is done, a 1/2" cube could still fit. Because the magnet plates are held in place by a screw alone on these trucks, they should be glued in place with the new magnet.
And there's why it's more difficult to replace the magnet in the older Sharks. The magnet is strongly attracted to the steel plate, and even a large amount of weight can't hold it to the track properly. Now here's the fix:
I glued a hefty spring to the top of the magnets, and glued a piece of thick paper to the top of the spring for insulation. The spring effectively holds the truck right where it's supposed to be, and still allows free rotation. More than a quarter pound of lead over the truck helps too (I have an early model with no extra weight cast over the power truck).
And the results are totally worth it! It only showed a 9.6% drop in speed to 85 scale MPH and didn't improve low speed control, but there was a 40.5% drop in current draw to 0.22A, and the torque is significant! I would recommend this change to all owners of Mantua's MU-1 powered models!
Darth Santa Fe!
This is an amazing post. For now, none of the information applies to my modeling but the knowledge and experience that you demonstrate are what I think great model railroading is all about.
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
sfcouple 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.......
IIRC, when the Hustler first came out, MR clocked one at a top speed of 429 smph.
Good info there on the neodymium magnets. I did a conversion like that on an old Athearn metal RDC which was running slowly, drawing about 3 amps, and generally not doing well at all. The motor had a vertical armature, which drove a gear train in the single power truck. Two 1/2 x 1/4 x 1/8" neodymiums replaced the original Alnico magnet, and it runs great now. Low current draw, consistent speed range, very reasonable perfomance for a 55-60 year old model.
Keep up the good work!
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Gary M. Collins gmcrailgNOSPAM@gmail.com
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"Common Sense, Ain't!" -- G. M. Collins
http://fhn.site90.net
The PM-1 should have had a stronger motor given the size of the magnet and pole pieces, but I guess they didn't give them much of a charge. The large open frame motor in their steamers at the same time had a lot of torque.
I wonder if we're ever going to see can motors with neodymium magnets used in modern locos. They would allow for more torque in a smaller package, and are already in Slot and RC cars.