Revamp cheap $5 gear motor. Subtitle: Return of the A-Board motor thread

[Chris333]

Tim what Roco locomotive is that and how is the electrical pick-up?  I want to build a NYC steam dummy, but can't think of a good 0-6-0 chassis that will run on it's own (without tender pick-up)

[victor miranda]

snip...
 I just received new phosphor bronze wire for the brush modifications.

I think I'm going to start with the .025 and .015 in 2 different motors. The current motor brush thickness on these motors is only .008" so it's really no wonder they wear out so quickly. So the plan is to make a "backup brush system". The commutator is silver so using a thicker stock should be ok against wear. Solder the bronze wire to the back of the thin brushes and then see how it wears. Fingers crossed.

rut roh.

spring tension in brushed motors is ...delicate...
you may want more meat but you do not want more tension.
Oh, and copper on copper erodes both evenly, you will lose brush and copper at the same rate.
You really don't want to lose commutator plate. 
Burnt out brushes is far better and cheaper to replace.

please try to find a way to apply the b-mann imitation brushes (and springs) to your target motor.

victor

[timwatson]

Tim what Roco locomotive is that and how is the electrical pick-up?  I want to build a NYC steam dummy, but can't think of a good 0-6-0 chassis that will run on it's own (without tender pick-up)

Chris, I cannot honestly tell ya which one it is. I bought a parts lot solely for it (without shell). An NYC switcher was my plans for it as well. The electrical pickup is really pretty good. The thing that stinks is the play in the axles. The side gears are the only reason it keeps in gauge. So shims around the axle are in it's future or I will wallow out the frame and add some brass bearings around the axles. The pickups in the videos are the stock ones going over a kato cross over so it's pretty good there.

Help me identify it I'll buy ya a cookie or maybe a beer.




6.98mm in dia. - 44" scale drivers.

No fear Victor I have over 100 small carbon brushes I want to test but I need to find a good conductive (inexpensive) adhesive first. Like you said you can't get them to solder to the fingers so we need glue.

[Chris333]

Haha. the beauty is that you can barely see the drivers anyways so they don't have to look good:

[timwatson]

Ah thats cool. Thats similar to their shays I want to do. Very little shay and a whole lot of wooden box.

[pjm20]

Looks like a very old Class 80:

[timwatson]

Could be but the siderods don't connect on the front and middle drivers.

[Ian MacMillan]

Basically what I'm looking for is a power truck with one axle. I'm powering some HO Custom Finishing MOW vehicles and am at a loss for powering the models that have single axles such as a Mark 3 or 5 Fairmont tamper.

The HO power trucks are just too big. Suggestions?

[pwnj]

Would any of these 90-degree gearbox motors work?

http://www.gizmoszone.com/shopping/agora.cgi?product=Gearbox&user4=GH90series;ppinc=1g

[mmagliaro]

Those Gizmos 90-degree gearbox motors are impressive for what they do in that form factor.
Only 8mm wide x 35mm long !  Heck, that would be great even for N Scale.

But...
Max rpm of 245 = 38 mph on a 52" driver.
I rather like that maximum speed, but I don't know about most people.

I'm more concerned about the rpm's on the motors themselves.  They are quoted at 34000 rpm for the 245 rpm output model.
Yikes,   34,000 rpm?    That better be some amazing motor with some amazing brushes if it's going to last.

The unit does cost 82 bucks, so maybe they put a great motor in it, but I'm not willing to spend $82 to find out.

[timwatson]

Basically what I'm looking for is a power truck with one axle. I'm powering some HO Custom Finishing MOW vehicles and am at a loss for powering the models that have single axles such as a Mark 3 or 5 Fairmont tamper.

The HO power trucks are just too big. Suggestions?

Ian, you could use an 8mm or 10mm motor in the vertical position and have the worm point down and connect it to a gear on the single shaft. One thing I'm going to try is to put a long driveshaft into a ball bearing with a worm on the end and make it look like a real bus drive shaft.

My crude mechanism drawing.


I'm not exactly sure what you're aiming for but maybe that helps.

This idea comes from the work Jeff B does and writes about on his blog. http://hon2jeff.blogspot.com/2013/01/distractions-again.html

[timwatson]

OK I had some time this last night to start the motor brush testing again.

First up, is an N20 motor, that has had a single folded over piece of .015" phosphor bronze wire, silver bearing soldered to it. It's been running for 12 hours as of right now we'll see if this simple mod gets it to the 100 hr.+ mark.
It was a relatively simple and fast mod - I have high hopes.

I'll report back when it gets into the 60 hr range since none of the other motors got past 40-50 hours.

I'm running it at 6v.

[randgust]

Ian, having spend an inordinate portion of my life pushing the envelope on tiny mechanisms....

You can do a single-axle drive even using a Kato 11-105 truck, I've done it, but the problem remains on the pickup side.    The 'hobsons choice' I ran into on the Burro crane was that I found a one-axle vertical drive unit that fit, and would move it, and had acceptable speed, but a four-wheel or three-wheel with traction tire pickup is very marginal and hates every switch it meets let alone any transverse warp on surface.   So you need, in one way or another, to figure out own to do a pickup system.   I settled on a permanently-attached 40' flatcar (with Kato caboose trucks) on the Burro crane and it was a complete success.   I also had to put a scale car on my Trackmobile, same problem.

But if you're trying to do a tamper or something similar, you need to focus on the pickup problem more than the drive.   That's what will ultimately defeat you - finding good wheels for that.    I'm very impressed by the TENDER wheels of the Atlas 4-4-0 as cantidates, but I don't think they are separately available.  Yet, anyway.  But when they are, they will be game-changers for this kind of thing.  I think about 18" wheels.

Down at Bedford I was running my tiny Climaxes with low-cost "M&M" robotshop gearheads and my Whitcombs (with the Kato 12V motor and the 5.14:1 gizmoszone gearheads) all day.   Still completely sold on those.   The current requirements are so low with a gearhead you can get away with a 100-ohm resistor in series and it won't overheat those, where it would a direct-drive 3v motor.