Now that my thrust washer question has been resolved, I need to ask about what would be the best practice for utilizing a universal drive shaft kit with that old Athearn Snow Plow. Would it be best to minimize the distance between the two shafts, the rotor shaft and the can motor shaft, given the need for the 2 receiving shaft sockets, balls and the metal shaft (presently 1.25 inches long)? The declination from the motor’s shaft to the rotor shaft is only about 1 mm. Is there a greater tendency for instability with a longer - or a shorter- connecting shaft, given the above? Cedarwoodron
If you have the “universal” kit say from A-Line etc, use the one that is closest to the proper length. If not, select the longer one and cut it down just so that you leave some play. Since you are not connecting to a swiveling truck, the install should be quite staightforward. You cound also use flexible tubing that will slip over the shaft and do the same where you adapt to the rotor.
cedarwoodron
I think the tendancy for instability would be greater with the shorter shaft length simply because the universal joints will have to operate at a sharper angle the shorter the shaft is. Logic suggests that the lower the angle of deflection, the smoother the shaft should run and the resistance (friction) in the joint would be lower with smaller angles of deflection.
Dave
With the amount of room available within the Athearn plow, why not mount the motor on the floor, immediately behind the rotor shaft, then connect the two with a piece of flexible tubing?
I just tried a NWSL 2032D-9 motor in an Athearn plow, and with the motor lying on its flat, the motor shaft is only a few thousandths of an inch higher than that of the rotor shaft. To drive the rotor, you don’t need a motor this large, and, by using a smaller motor, you could construct a mounting pad to match the shaft heights perfectly.
Most can motors use a 2mm (.078") shaft diameter, while the rotor shaft is 3/32" (.0938"), so flexible tubing is an excellent choice for coupling the two disparate sizes.
Also, while you’re pondering your options, check the rear bearing for the rotor shaft. Mine, brand new and never run, has an inside diameter of of about .098", a pretty sloppy fit and therefore a great noise generator once that motor winds up. U-joints will generally acerbate noise to some degree, depending on their tolerances.
Wayne
Well, the rotor shaft height is a fixed dimension, as the support metal is riveted tothe existing car chassis. The can motor, lying on it’s side has that very small higher angle laying flat on the car chassis, so leveling would involve material removal under the motor location that might weaken the car rigidity itself and introduce greater potential for misalignment and vibration issues. I did seat an additional “thrust washer” on the shaft immediately behind the rotor hub, which enables the rotor to stand a bit more proud of the snow shroud housing. That seems to alleviate the plastic-on-plastic clatter of the rotor against the shroud. My Igarishi (?) motor has very similar characteristics to the NWSL 2032D-9, and is almost the exact same size, so I don’t think spending another $34.00+ for another motor is wise on this project. There is some “generous” tolerance where the rear of the shaft passes thru the rear shaft support hole, but I cannot think of anything that I could put in there which would not create potential for additional binding/ and or friction.I will lightly lubricate the assembly, but it’s the length of the brass connector between the two shafts that still concerns me. One other source mentioned that too close is more prone to irregular movement, and that the farthest distance is preferrable. Still a bit perplexed, however… Cedarwoodron
Sharp joint angles are to be avoided. Newer locos don’t even have joints in many cases on the flywheel since they are a hex drive. Someone mentioned tubing, if you can get the ends to connect that’s not a bad option for quietness.
Richard
The easiest and cheapest solution to the motor-mounting problem is to simply cut a hole in the plow’s floor - place it right behind the casting for the rear rotor shaft bearing and make it only lightly larger than the size needed to accommodate the motor’s housing. Don’t waste effort trying to remove material from the top of the floor. Once you’ve cleaned-up the edges of the hole, use solvent cement to affix a piece of .060" thick sheet styrene to the underside of the floor, then use sheets of suitable thickness to build-up the inside of this lowered area until the motor shaft lines-up with the rotor shaft, using flexible tubing to connect the two. Once the cement has set, the floor will be as strong as the original.
With this method, you’ll need to fashion a mounting bracket for the motor (sheet brass works well) and attach the motor to it, and the bracket to the floor, with screws.
An alternative is to build-up the lowered area of the floor somewhat as described, then use silicon sealant or caulk to affix the motor, applying an amount sufficient to both hold the motor in place and bring it up to the required height.
Don’t make this project any more complicated than necessary: if you have the materials on-hand, the latter method can be done in an hour-or-so, but make sure to let the sealant/caulk set for at least 24 hours before applying power. If you opt for a bracket, that will add a little time to the build, but will be useable as soon as the installation is completed.
Wayne
To select a drive shaft length several things need to be considered. For a stationary motor and target device it is rather easy. The shaft length only needs to be shorter than the bottom of the receiver cups. The shaft should not be loaded into the bottom of the receiver cups. It will cause a huge increase in turning friction. This is solved in autos with a telescoping device.
For drives to a powered truck that turns…as in a Diesel loco… it must not seat in the bottom of the cups when loaded up to the or to be able to drop out when turned to an extremity. Translation: the drive shaft must stay in the cups when moved up and down as in walking over a high spot in the rail and also turns side to side and the stops built into the loco.
If the drive shaft gets to the bottom of the cups in a turn for example, it will cause the loco to become very growly at that turned location.
As noted above NWSL has the best options and work well from the shortest little dumbbell link to providing shafting up to six inches (available separately).
They also offer the cups in any number of metric and common fractional inch sizes.
see ya
Bob
The number one reason, in my opinion, for projects not getting finished, or, in many cases, even started, is over-thinking, over-engineering, and over-complicating. There are situations which require additional thought and more complicated solutions, but this isn’t one of them. Just do it. [swg]
If you weren’t so far away, I’d invite you over and do that installation while you waited. Bring the motor and the plow, I’ll provide, gratis, the styrene, drive shaft tubing and the labour. [(-D]
Wayne