Overmod But note that he HAS tested the motor outside the chassis, and HAS verified the issue to occur in the isolated motor precisely as it appeared when installed. And he said he roll-tested the chassis for binding when the motor was out. I don't think it's 'worth' trying to fix the motor, other than to do some forensics on what's causing the observed issues. Replacement -- ideally improved replacement now that that famous mother, necessity, allows for invention -- is the sensible track to follow going forward.
But note that he HAS tested the motor outside the chassis, and HAS verified the issue to occur in the isolated motor precisely as it appeared when installed. And he said he roll-tested the chassis for binding when the motor was out.
I don't think it's 'worth' trying to fix the motor, other than to do some forensics on what's causing the observed issues. Replacement -- ideally improved replacement now that that famous mother, necessity, allows for invention -- is the sensible track to follow going forward.
Simon
Confirmed from the seller that the mounting holes are 10mm apart and take 2mm screws.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
Tom,
I think it is not necessary to drill new holes - just make a "groove" from existing holes 1-1,5 mm towards the center. It seems to me, after looking to picture you posted that motor holder is held with two screws to loco chassis, so it is not difficult to remove it and work on it. My idea is that these grooves intentionally enable some movement of the motor to fine adjust motor into perfect position.
My proposal is to solder wires to motor contacts, and connect them to DC power pack after you temporarily install motor in its position with screws not fully tightened. Then, with minimal possible DC voltage that enables motor/wheels to rotate try to find "sweet spot" where motor works without any resistance within hex coupler. When you find it, tighten both screws fully.
Another thing is very important - pressing back hex coupler to motor shaft. If fit is too tight, you could practically destroy the motor if you press this part too hard on motor shaft. Unfortunately, this motor does not have dual shaft, so there is no shaft on the other end of the motor that can be used as support while pressing hex coupler on.
Therefore, if necessary, widen the bore in hex coupler wide enough to be able to press it on without excessive force. If you widen it too much, then you can first use anything to make tight fit between motor shaft and hex coupler (e.g. piece of paper towel or piece of sewing thread) to test how motor works when installed. After you are 100% certain everything works fine, you can glue this part on motor shaft with some glue (e.g. 2K glue with at least 5 minutes of working time). I would avoid AC glue (especially fully liquid one), because it could penetrate to motor bearing, and in some cases, fix the hex part before you slide it in wanted position (happened to me several times, because AC glue is very fast).
Do not get me wrong - I do not have the impression that you are not capable, but I know how many "surprises" I had during remotoring of my locomotives (at least 40 until now), so I just want to pass on my experience which I think can be useful to you, or any other member of this forum.
Just one note on general design of coreless motors - their rotor is in fact a bell made of wire windings (without any iron core - therefore very fragile), and it rotates AROUND stator (cylindrical magnet) that has a bore in the center (for motor shaft). Longitudinal movement of the rotor is prevented only thru metal ring usually pressed on motor shaft outside of motor casing. At motors with just one shaft, shaft is not supported at all on the other side (there where commutator is located). Nice picture explains better than words - here a comparison between iron core and coreless motor design (Citizen motors).
Hrvoje
If this was my engine, I would change the coupling component. These motors are of good quality and I would suspect that the problem is associated with that odd coupling system. I've used tubing on 3 or 4 brass engines and they all work very well at all speeds. As for the motor connection, I would remove the brass bracket and build a new base with plastic, and use caulk to hold everything in place. I see no advantages in keeping the original coupling system, but I see a lot of "smoke" suggesting that it burned your motor, and might do the same with the next.
Anyway, that's my worth.
snjroyI would suspect that the problem is associated with that odd coupling system.
Agree, many of the NWSL U Joint kits come with a close-install "dogbone" that should work.
-Kevin
Living the dream.
I've used silicone tubing and NWSL u-joints for driveshaft couplings and both work well. I've never seen this particular design before and would agree that it looks less forgiving and less flexible than the other two options.
And considering the difficulties involved with pressing that coupling on an assembled coreless motor's shaft, I cast my vote for the tubing, with fallback to a close U-joint if the tubing 'fails to thrive'.
I also believe flexible tubing is the best way to connect the two shafts. I even doubt whether you can fit the universal in the limited distance.
Universal joints are very good at accepting radical angles of drive. That's not needed here.
Universal joints are very good at transmitting power across a goodly distance. That's not needed here.
Ed
The replacement motor arrived this afternoon and I installed it onto the original bracket that I pre-drilled 10mm x 2mm OD spaced mounting holes to accommodate the new motor. I also opted to use Du-Bro silicone tubing for coupling the gearbox & motor shafts, which worked well for my previous NYC brass boxcab project:
Most importantly, the new motor is working quite well and smoothly - especially at slow speed. (Thanks, Hrvoje!) Current draw is extremely consistent and low: At speed step 030 it fluctuates between 0.04 & 0.06A. Also zero spikes and it's operating cool as a cucumber.
As with my previous setup, the LokPilot is only temporarily soldered in place for testing purposes. The 18 x 18mm motor housing will give me more headroom for the decoder inside the boiler. Like my other DCC brass installations, I'll be adding front & rear headlamps. I'll also be adding another SMD LED to the backside of the backhead to mimic firebox flicker. The brass casting for the backhead has the firebox door open.
My one disappointment is that I won't be able to use/add the supplied lead weight to the front part of the boiler because someone (I'm guessing the manufacturer) soldered the front boiler plate on enough that I fear damaging it trying to get it off. Sometimes the boiler plates are just press fit in. However, I can see at least 3 or 4 small solder spots along the boiler plate seam. Even cutting along the seam with a sharp X-acto knife to score the solder doesn't open them up. I'll find other ways to add the weight.
tstageAlso zero spikes
Tom, this is all very good news to hear.
It is always good when a brass steamer is made ready for the fleet.
Good luck with the lighting and decoder installation. Even though I do not do this, I would love to see your work.
Thanks, Kevin. I'll be sure to post photos when I get 'er done. I may still purchase a couple of inexpensive but quality can motors to play with for comparison (Minebea being one) before buttoning this one up.
Tom, I am glad motor is good for your locomotive. But, can you test this locomotive for minimum flat DC voltage required for locomotive to move on flex track? I am curious, because most of my locomotives move at around 1 - 1.5 VDC, or even less.
I'm glad to hear that the results are satisfying. And thanks for sharing the picture: I like brass - inside and out!
I agree, Simon. In fact, most of my locomotive purchases over the past few years have been older brass unique to my prototype (NYC); some at very reasonable prices with very good detailing. It's been fun to convert them to DCC and wire them for SMD LED headlamp lighting and occasionally sound. And it's the only way I'd be able to procure those particular models since they will - more than likely - never be made in anything other than brass.
I've only had one brass locomotive that has been a disappointment running-wise. All my other acquisitions - steam or diesel - have been very smooth runners. The disappointing road switcher I plan to replace the gear towers with Stanton drives.