im asking if it matters whether the poles are oriented north and south (top and bottom) or east and west (side to side).
Modeling the Baltimore waterfront in HO scale
The poles are oriented to create a magnetic circuit through the metal open frame. That means north and south point up and down, and butt against the metal.
Whether north or south is up determines which way the armature will turn when DC of a given polarity is applied (I.e. which way your reverse switch is positioned). If it turns the 'wrong way' to be consisted with another locomotive, put the magnetic stack in the other way.
Jetrock, once you make the jump to powered overhead wire for the interurbans and trolleys, you make both rails the ground side of the circuit and the pole the hot side. I found that really helps with power pickup on the old Suydam cars, even the early runs with brass(non plated) wheels. A good quality trolley pole is also esential. I found some with a fabricated shoe touched the wire with the soldered joint and the impurities in the solder tended to gum up the shoe after running awhile. I replaced the shoe with a solid brass cast shoe or a whole new pole and problem was solved. Mike
Silly NT's, I have Asperger's Syndrome
I ordered some 1/2x1/8x1/8" neodymium magnets and they arrived today. I stacked 5 of them in the frame and used an exacto blade as a spacer. The motor runs fine, thanks to the information provided.
If you have a Harbor Freight store where you live, they care little button size Neo magnets. I bought several packages and used them in my ailing motors in my old brass interurbans. Motors that once ran hot enough to fry and egg, now barely get warm after over an hour of non stop running. You get enough to do one motor per package at $2.34 per package. I had 3 left over from each package so eventually(depending how many each motor takes, you get another motors worth. They fit perfectly between the screw at the rear and the rear armature bearing. Just close enough to keep the oil felt wick material for the rear bearing in place. Mike
I didn't have any luck with the Harbor Freight circular magnets. At 5/16" wide, they were too big to fit in the MDC loco I tried them in.
Some motors are just to small, the ones from Micro Mark are even larger than the ones from Harbor Freight. That motor is quite small in my pic, But I do have even smaller open frames in my parts box from models that got can motors. I save all of them for spare parts.
Started reading this thread to find out what the heck a neodymium magnet is. Still don't really know exactly WHAT they are but some of the replies clicked and I remembered an unfinished Penn Line PRR M1 that's been sitting on a shelf for about 20 years.
I've wanted to convert this engine to DCC but hesitated because of the problems with replacing the original motor with a can motor and the expense of doing that. Upgrading the open frame motor with neodymium magnets sounds like the best solution.
Any advice or recommendations for this upgrade?
ChuckAllen, TX
cefinkjrAny advice or recommendations for this upgrade?
Hi Chuck,
Penn Line used Pittman open frame motors so the conversion should be easy and fairly effective. As others have shown, you need to measure the size of your existing cast magnet and figure out what size stack of neodymium magnets will fit in the space. If you can't get an exact fit, use steel shims to fill the gap. If you can't reinstall the original rivet or screw that held the old magnet in place, don't worry about it. The magnets will actually hold themselves in place (if shimmed properly). You can use a little CA to fix them in place if you wish.
I'm not sure how much you know about Penn Line products, but this might be of interest to you:
http://www.tcawestern.org/penn.htm
Good luck,
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
Thanks for the info and the link, Dave.
The M1 wasn't mentioned in that history of Penn Line so I'm thinking now that it may have been in some pre-release stage of development when Bowser acquired Penn Line. I'm traveling right now so I can't check but I'm pretty sure the Builder's Plates on the smoke box have P-L on them (or I'm confusing the M1 with an older H9 that I have).
This older post involves some of the details of using neodymium-iron-boron magnets (NIB) in the DC-71 Bowser motors. Note the precise dimension quoted in one post.
https://model-railroad-hobbyist.com/node/17774
Be aware that the plating on these magnets is important. You should not cut or file them 'to fit' or they will corrode (and any crumbs or dust will pose a variety of hazards). Note the recent tip that flat metal cutting blades can be used as magnetic shims here...