Hi folks. I am debating trying to remotor my Key H6. It currently has the original open frame motor and the factory idler gear tower that is part of the frame. Another user here was kind enough to send me a copy of a short word document that has some information about how a user on the Atlas forum several years ago regeared theirs. They cut off the old cast gear tower, manufactured a new one from square brass stock, and installed a new motor and worm gear. The two pages of the word document that show the process are shown below. My question, I suppose, is: will this cure gear noise? My loco doesnt run as well as I believe it could, and it is very loud in reverse. I hope to both improve running and quiet this thing right down. Is this a method which should do so? Also, how do I know which idler gear and spur gear (I am unsure what the screw part, and the gear that meshes with it, are named) to use? NWSL seems to only deal in HO, and their information is somewhat overwhelming. Do I need to do the gear tower bit, or will a new motor help? This is the one I have listed in the swap meet. It's gorgeous, but if it doesn't sell, I may as well remotor / regear it. Amanda
Since you are in the Netherlands, you should become acquainted with the brothers, Marc and Hans Starmans. They are THE gurus for re-motoring and custom builds. I don't know whether they are on this forum, but they might be on the Railwire. They might be able to offer an even more elegant solution than what is depicted in the one from the Atlas forum.
Here is their Facebook page with contact information and examples of their work. www.facebook.com/NStars/
I wonder if I need to remove the existing gear tower; the gears seem to have a bit of side to side play, as do the geared axles. I don't know if they should?
You really need to see the N trak steam Annual, especially the latest two,the 2016 and 2017 editions. Available from Ntrak.org, click on publications. You could probably write an article or two for the next edition. If you could get the Starmans to look at it, that would be great. As to this particular engine, I have no experience. The worm gear - the gear attached to the motor shaft - looks like one out of any atlas diesel model. So do the bearing blocks.
First, let's get the terminology right, so we know what we are talking about. The spiral gear on the end of the motor shaft is the WORM. It is usually brass, sometimes steel. The toothed wheel that meshes with the worm is the WORM GEAR. It should be plastic, although sometimes brass is used. The other gears that transmit motion to the drivers are SPUR gears. Second, relative to the pictures of Ebi's modified drive: The worm is either the original or a re-purposed Kato worm. He used Kato bearing blocks from an old Kato PA (the ones with the ball-shaped bronze bearing molded into the block). Third, the important modifications are (1) precise support and alignment of the worm relative to the worm gear, (2) better quality motor, (3) proper coupling of the motor to the worm with a universal joint (or in this case, silicon tubing).
The Starmans have a very good reputation. The gentleman who posted that to the Atlas forum, Ebi, is an ABSOLUTE genius with N scale steam. That guy can fix ANY problem in N scale steam. When Atlas shut down its Boards, I forget if he went here or to another Board, but I have not seen anything from him in quite some time.
Thank you much for the vocabulary information! That will help clarify things, I imagine. The original worm on this engine is attached to the long rigid shaft which extends from the front of the motor. The worm shown in the photos above is a replacement. I do need to get all the N trak annuals! They're just rather pricey, plus the fact I live in Europe, has delayed me some. I think when/if I sell something (I also have a few guitars up for sale at the moment - my other hobby) I shall use some of that to get the N trak books. I have also emailed the Starmans, and shall see what happens! Here is a photo of the current motor and drive setup:
After looking at the photo I remember several steamers I had that had that long drive shaft with the worm out on the end giving some trouble. When changing direction the motor torque would slightly rock the motor and cause the worm gear and the main gear to slip. My solution was to anchor the motor more firmly and I may have even shimmed the back of the motor slightly. Been a long while so excuse my memory.
If it is noisy in one direction only, I would also check how much the armature is moving along its axis when trying to run in the noisy direction. In the photo I can see a nylon colored spacer that looks like it would control the thrust in one direction, but I cannot see what controls the armature from moving rearward too far. If the armature is allowed to move too far, the worm will get too far out of alignment with the worm gear and it will be noisy. Ebi's solution to use a worm mounted with its own thrust washers is elegant, since the thrust of the worm will no longer push on the motor shaft.
This is probably a good time to warn you about "sticker shock" concerning brass upgrades. The coreless motors (like Maxons and Faulhabers) that are typically used for re-motoring are used primarily in medicine and aviation and are built to tight tolerances. As such, they are also perfect for our small N scale projects. The trouble is they are rather pricey - $50-120 depending on type and source. Besides the motor, there is considerable effort or expense to buy or build a gearbox to support the worm. So just be warned.
I will try shimming the armature, though I have a feeling most of the noise is the gears themselves. I do not mind spending some money on a project like this, after all; remotoring costs about as much as buying a new N scale diesel, and most of us would happily buy one of those! Unless I wind up swapping to HO (possible, to be honest) I'll do the upgrade. I am simply having trouble FINDING the right motor. =(
Where are you searching for motors? Eldon Shirey, aka The Motorman ( www.micro-loco-motion.com ), finds surplus motors for re-sale at good prices, of course, he is in the USA so maybe not so easy for you to work with him. The Maxon and Faulhaber motors are made in Europe. There should be distributors close to you. Maybe ask the Starman brothers for help finding motors.
I have in fact been in contact with Eldon, and that is probably where I will source a motor from. I hope I can manage to NOT mess this up! Amanda
Sadly, I regret to report that the Motorman, aka Eldon Shirey, has passed away. https://kirbysmithrogers.com/tribute/details/954/Eldon-Shirey/obituary.html