Rubber mounting athearn motors

[Anonymous]

I'm thinking about trying this on my athearns to make them quieter. I have a set of CW44-9s or whatever in SF warbonnet, and I've made other improvements like grinding off plastic retaining the middle axle on both trucks so it can move back and forth, so now they don't derail hardly at all. Now I want to kill the noise, so I'm thinking of rubber mounting, like they use in computer hard drives and stuff.

[loathar]

My older Athearns all have factory rubber mounts in them already. Is this not the case in the newer ones? On the Helix Humper web site, they show reusing the factory rubber mounts with their new motors. I could see where adding some silicone would help.

[cwclark]

my problem with the athearn motor mounts (if you call it a problem) is that after years of service the motor mounts deteriorate, become brittle, and break apart...what I do is cut a piece of thin rubber sheet gasket material, make holes in them with a hole punch tool to correspond with the holes in the motor, and cut it to fit in the two slots in the frame (don't use too thick of rubber because then the frame pickups on the bottom of the motor won't make contact to the frame)...then i'll run a 2/56 tap through the holes in the motor casing and insert 2-56 screws into them from under the frame side and through the motor hole brackets... I shim the screws with pieces of styrene tubing so they are tight and the motor won't jerk around...the only thing is that you'll never get rid of that athearn growl no matter what you do to it...it's just naturally a noisy but reliable motor....chuck

[selector]

I wonder if those black or tan felt floor pads for furniture legs would work better and longer. No plastic or rubber in them to break down over time. Remember, there is a lot of ozone-creating arcing in and around those locos, and ozone is damaging to rubber.

[Anonymous]

Well, I had one of the motor out of one of my locos once, and I hooked it up and it wasn't that loud unless I put it down on the table. Thats why I think if it had something better to isolate the vibration it would be quieter.

[Anonymous]

Here's what I do to tune the Athearn's. I too have a couple of AC4400's, and with a little work they'll run like a champ and be fairly quiet.

1. Remove and dismantle the trucks. Clean them up, and lightly grease the gears and especially any axle areas. Use a plastic compatable grease, or a silicone grease.

2. Dismantle the worm gear head. Is there any extra play in it? Find a SMALL washer and shim the end of it to remove any extra play. You want just a smidgen of play in it. This is a source of noise. Use light oil on the worm gear thrust bearings, and heavy grease on the worm gear itself.

3. Reassemble the trucks, mount back in body, and attach gear head. As you mount the gear head glue the motor end of the drive shaft in place with a smidgen of silicone caulk. This will prevent lash in the driveline and remove noise. This will also allow you to remove the driveline in the future if you need to.

4. Clean the motor armature with a pencil eraser. Wash it off afterwards with a Q-Tip and alcohol, nothing stronger.

5. Add lead sheets to the top of the body. Add as much as possible. You'll need to CAREFULLY measure the body and the frame to see how much you can add. Fill every space possible. If you're careful you can add as much as 12 ounces of lead to the locomotive.

6. Hot-wire the locomotive by replacing the copper "flap strip" that makes contact to the trucks with a thin wire soldered between the top of the motor and the trucks. Remove this from the motor before soldering it so you don't ruin the motor brush springs. Watch out as you remove it that the springs don't go shooting across the room! You can trim off the unused ends of this copper strip so that all you have left is the part that clips onto the motor holding the brushes in place and the jumper wires to the trucks.

When you're all done you now have a much quieter locomotive that'll pull the paint off walls that will run smoother and be more reliable.

Mark in Utah

[Darth Santa Fe]

It could be that something is off balance. Have you checked to see if the flywheels are off balance? I've quieted a couple of my Athearns down by drilling small holes in the part of the flywheel throwing it off balance.

It could also be that the motor bearings need oil, or it's just got a noisy commutator.

[Anonymous]

Well they're really not THAT loud. It's just the everyone always complains about them being noisy compared to other brands so I'm looking for ways to bring it down. I don't think they have any defects. Anyway, I've bookmarked mark in utah's post so I'll do all that probably.