Keystone Shay NWSL upgrade

Discussion in 'Logging, Mining and Industrial Railroads' started by camelot, Dec 28, 2003.

  1. camelot

    camelot Member

    another pitcure of the boiler fitting over the drive gear...

    Attached Files:

  2. shamus

    shamus Registered Member

    I used the NWSL bull gear and universals on an MDC "Roundhouse" kit, I will be interested to find out the results when using these with the Keystone shay kit. keep posting photos as you do each stage please, would also make a good "How to" for later as I can split it off this thread.
  3. camelot

    camelot Member

    The keystone trucks are replaced with NWSL parts in total , its a bit of a "fussing around" job , the main hickup was glueing the journel covers (see picture)over the lineshaft and not bonding everything togeather.

    I found a solution on a website here that suggested coating the lineshaft with grease and using gel superglue to hold the lineshaft in a small tight positiom with NO lateral movement , crucial to smooth operation .

    I must say that it works a treat :D

    Attached Files:

  4. marc gast

    marc gast Member

    Keystone Shay


    You are getting there. As we mentioned, this is not a conversion process for the faint at heart. It does make a very nice Class A shay.

    As a note to Shamus, I don't use the NWSL bullgear, etc. for the MDC shays. I replace them with the same gear box used for the Keystone conversion. Much quieter, still handles the load and can be hidden with a firebox. Try one of these.

  5. camelot

    camelot Member

    I have put the basis of the tender,Cab together with the mainframe and trucks , here is a picture of my 3 shays to give you an idea of how small this Keystone Shay is , closest is the Keystone shay , next the MDC 2 truck shay and at the end , the Spectrum 3 truck shay , all HO scale..
  6. camelot

    camelot Member

    heres the picture this time ..

    Attached Files:

  7. neilmunck

    neilmunck Member

    It's tiny!

    I like the weathering job you did on the MDC shay. Very nice.
  8. camelot

    camelot Member

    The motor has been installed , all runs reasonabley well but a little hot?

    Marc and/or Jeff , did you experience this ?

    It says maximum continuous safe current is .025 amp , how do i check this ?

    I have the can motor BTW


  9. Jeff Law

    Jeff Law New Member

    I find the open-frame motor runs quite hot in my 1st Shay.

    The second Shay doesn't run well enough yet (!) to be able to tell.

    I am building a Class B Climax with the NWSL kit and, even though the motor is totally exposed at the moment, it still gets quite hot.

    Jeff Law
  10. camelot

    camelot Member

    Thanks for your reply Jeff , i was quite surprised , none of my other motors run that hot ,especially after once around my 6 x 4 layout with the tender off and the motor exposed.

    I ran it about one quarter throtle as well.

    I need to get it running better a bit backwards, the rear tender tends to lift of the track arround curves going backwoods and there is a clicking sound as well :(


  11. Jeff Law

    Jeff Law New Member

    It might run quite hot, but my first Shay spent about 12 hours, over 2 days, running almost continuously at an exhibition last year.

    Jeff Law
  12. marc gast

    marc gast Member

    Running Hot

    Well, first question, are we all talking about the Keystone conversion or other MDC shays and Keystone converstions.
    Cam, what can motor are you using in the Keystone?

    In answer to both, none of my motors run hot. See items 1, 2, 3, below for investigation of the hot motors.

    Three major items that will cause excessive heat build up on these engines.

    1. Binding of the motor shaft to the gearbox if no interfacing driveshaft is used. Never connect the u-joint of the bullgear directly to the shaft of the motor. Especially, the Keystone. No matter how precise one is in aligning the motor to the bullgear, there is always misalignment. Build a short independant shaft between the motor shaft and bullgear. This will reduce any type of binding in this area that creates heat. Remember, binding creates extra stress on the motor and it becomes overworked, notibly in smaller motors. If using the open frame motor supplied with some of the NWSL Keystone shay conversion kit, trash it a go to an A-Line 12-20 or similar size can motor. Also, if you can not get both trucks to spin freely by turning the u-joint on the upper part of the bullgear using your fingers, you have a bind. Take a smaller motor, hold the shaft between your fingers and increase the voltage. You'll understand the binding theory.

    2. Drive wheels not square to the frames. White metal does have a tendancy to bend, etc. The NWSL replacement axle/gear set needs to be honed into place. If you cannot easily spin the two axles on each truck with you fingers, then there is also binding. This is probably the greatest area of concern. Water soluable valve grind compound is needed to hone the worm. spur, and bevel gears. NWSL does great work in machining these gears, however, no two are matched. Pack a little valve grind compound in the bevel, worm and spurs gears, hook a small T shaft to the shaft u-joint on the truck and begin turning by hand. Back and forth until it begins to spinn freely. Then take the small T shaft, insert it into the chuck of a small drill (not the 24 volt puppies) and then begin slowly spinning the shaft once more, increasing the revolutions slowly. Make sure you hone the gears in both directions.
    3. Just as in the MDC shay, the line shaft needs to be timed. If the timing (alignment) of the shaft gears between the front and rear trucks are not aligned properly, they cause binding and also will cause the motor to run hot.

    As a note, all of these items apply to the MDC shay and climax, except for the sideshaft since the climax runs off the center shaft.

    I would suggest drilling small holes in the tenders for some ventilation. I am a wood burner, so the holes are decoyed by the wood. Oil burners would need a little more care in finding areas to drill the holes so not to be noticed.

    The Keystone shay does have a tendancey to want to crawl the rails (what prototype shay didn't). This is more than likely due to the timing of the side shafts or the truck frames not at a true 90 degree angle to the drive wheels. You may want to check the gauge of the wheels also. Shays are a little more sensitive running backwards than forwards.
    One last note, the lenght of the center drive shafts from the bullgear to the trucks is quite critical. The shaft should have a small amount of longitudnal play between the bullgear and truck when the wheels are aligned straight.

    Hope this helps answer some questions.
  13. camelot

    camelot Member

    The NWSL Keystone Shay conversion and i am using the can motor supplied with the kit.

    Ok Guilty of that , i was under the impression that the less moving parts the better and the quieter it would run. Also the MDC shay is directly conected to the gearbox, so i thought it would be better to do that

    I have now cut in a small cardan shaft as you mentioned , not sure if it makes any difference and i am running it without connecting the trucks to the bottom shafts but the motor still gets warm very quickly , maybe i am not used to these motors.

    When i say the motor is hot , i mean warm to the touch , its not burning my flesh or anything.

    Heres a top view of the shay with the motor and gearbox installed..


  14. Jeff Law

    Jeff Law New Member

    I've put together a web-page of hints/tips for this kit project.

    If you're interested, see

    I don't claim to any great authority on these things, but I have discovered a few things about them whilst trying to get them to run well!!

    I'll post some pics of my Shays when I get a few minutes!

    There is also a link near the bottom featuring a Class B Climax I'm building using the same NWSL motorizing kit.
  15. krokodil

    krokodil Member

    Hi Ian

    I also did this conversion some years ago. The main thing is that you must be very careful with can motors (it happened with MDC Shay as well). Those motors when not running on optimal speed will be heavily overloaded (hight torque is required) and may burn out. (Their resistance to be overloaded is much more lower, because of missing iron core).

    Since this experience I always use a spare open frame motor to start any new locomotive kit. When I reach a smooth operation (checked mechanically and electrically as well - low current draw) I replace the spare motor with a supplied (or final) can motor. This saved me at least 3 motors in my different scratchbuild locomotives and other vehicles,:eek:
  16. marc gast

    marc gast Member

    Shay - Can motors

    Most can motors are accompanied by a flywheel. A flywheel also helps out in the enertia aspects. Because the can motor doesn't have the magnet mass of the open frame motors, the flywheel helps to get it going add momentum during revolutions.

    I used a small flywheel in my Keystone shay. There is room for one; utilizing the double shaft on the motor. Can motors can run a little warm as the ventilation is not as great as the open frame motors. Don't get me wrong on open frame motors, some of the larger ones with a flywheel work very well. The can motors just have a better low end response due to the encased design.

    I have also used the open frame motors for beginning projects, however, there is not a small enough can motor to be able to break-in the shay running on the track. Usually, it will be a bench break-in with the frame mounted to a solid block and the motor attached somewhere else other than the frame.
    As the NWSL and Keystone instructions mention, this is not a kit for the faint at heart.

    Looking good though!

  17. camelot

    camelot Member

    Don't get me wrong the Shay kit has been a little easier so far than i thought and it runs well , it was just the fact that the motor seemed warmer than i am used to.I have now come to the conclussion that this is typical of this can motor in particular .

    I will do what krokodil recomends and experiment with finding a good running speed.

    On that note can anybody tell me how to check the current draw
    of a motor when running , i have not had to do this with any of my other kits as yet?

    I feel that the hardest part , side gearing and line shaft , has yet to come.

    Thanks for your reply Jeff , i look forward to seeing pictures of your Shay.

    Here is a picture of the underside of the shasis , i made some eye hooks ,drilled them into the u/side to keep the pickup wires in place , a little ACC added to help hold the eye bolts in place.This idea was borrowed from the MDC Shay handbook



  18. Jeff Law

    Jeff Law New Member

    Nice work Ian!

    It looks really great thus far.

    I do like the hooks to 'tie down' the power leads - I'll take that on board, if you don't mind!

    The motors in both my Shays are the open-frame variety - I suspect that these do run quite hot by design.

    As mentioned on my hints page, I'm experimenting with captive, slide-coupling drive-shafts for the Class B Climax so will report on those when I get them made. This idea is due to a) the inclination for the shafts to drop out on maximum deflection, and b) my experience with the plastic coupling ears 'chewing off' after prolonged running.

    Keep up the good work!

  19. marc gast

    marc gast Member

    Wha'D You Shay?

    Looks good both of you!!!!

    The idea of a sliding drive shaft sounds good. Hobbytown has used this method on all of their items. With a little work, that would be great. Also, using two different sizes of square hollow brass would work. I use this method for all of my large scale geared engines. More prototypical. I would think one could attach the square stock to the round shafts without much problem (leaving enough clearance for the sliding of the inner shaft. Give it a try.

    Necessity is the Mudder of Devention! LOL
  20. krokodil

    krokodil Member

    Hi Ian,

    the easiest is to get an Ampermeter (range up to about 1-2 Amps). Wire the meter in series with the motor and test the current. The motors usually have their maximum (if you do not know this value, you can test it yourself, at about 50% (6V) of nominal voltage - 12V- stop the motor and take a note about the current Imax). Then test the motor in free running (no gear attached) at nominal voltage (12V), this is I min. If the Imin is very close (or bigger) to Imax, the motor is not designed for 12V, and will run hot.

    When the gear is attached I always try to reach the middle current between Imax and Imin. You will see in the beginning the motor current will be very close to Imax, and after the break-in this value will decrease. All those current values are very motor specific, so you have to get your own values.
    Never run the motor with higher current than I max (at 12 V it is very easy).


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