I have a number of Athearn blue box engines. Most of them have what some people have referred to as an Athearn Sound Unit as they make quite a bit of noise. Seems when the shells are off them they’re very quiet, but are noisy with the shells on. Anyone have some ideas of things to do to quiet these guys?
http://www.trains.com/community/forum/topic.asp?TOPIC_ID=6100
Give this link a shot, these guya are using Pearldrops tooth paste. It’s here on the fourm
A little bit more oil than needed works for me (careful to much causes slippage)
Here’s what I do to tune the Athearn diesels. With a little work they’ll run like a champ and be fairly quiet.
-
Add a low-abrasive compound in the trucks to increase the wear on the gears, to run them in. Many people use Pearl Drops tooth polish, but it’s hard to find. I use Soft Scrub. Run the locomotive both directions for about ½ hour under light to medium load.
-
Remove and dismantle the trucks. Clean them up and make sure you get all of the compound out of them. Lightly grease the gears and especially any axle areas. Use a plastic compatable grease, or a silicone grease. Remember, heavy grease in slow moving areas, oil in fast moving areas.
-
Dismantle the worm gear head that was connected to the top of the trucks. Is there any extra play in it? There usually is. 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.
-
Reassemble the trucks, mount back in body, and attach worm 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.
-
Clean the motor armature with a pencil eraser. Wash it off afterwards with a Q-Tip and alcohol, nothing stronger.
-
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. The lead both quiets the locomotive AND aids in its traction. I actually use lead blocks that I hammer into shape and trim off the excess. Use glue to hold the lead in place. I use GOOP. Some people use double stick tape, but it takes up valauble space in the shell.
-
Hot-wire the locomotive by replacing the copper "fl
1.Start with the shell.Add 4-6 pieces of stick on weight to the inside top
of the shell.This cuts down on the shell chatter cause by the way Athearn
mounts the shell to the frame.
2.Disassemble the trucks.Now look for burrs and other foreign matter check
the brass bushings for any burrs.Reassemble the truck and sit aside.Now
repeat this process on the other truck.
3.Now check the flywheel to insure it turns freely…
4.Check the motor to insure its seated correctly and tight.These can be knocked loose during shipping.
5.Check the drive shafts and u joints for burrs.
6.Check the end bushings and worm gear for burrs or other problems.
7.Reassemble the drive.Add NWSL wheels if desired.
8.By using one very,very small drop of oil,oil the gears,drive
shafts,bushings,flywheels and flywheel shafts.Work oil in place by hand by
turning the drive with the flywheel.
9.Hard wire the motor pickup wires.The metal clip will work but,I found by
hard wiring the motor pickup wires the locomotive will run slower.
10…Now,The fun part.Let this unit run forward for 45 minutes at medium
speed.Stop and reverse the unit at the same speed for 45 minutes.You should
be able to tell a difference in your locomotive.
Again I want to stress use only a light small drop of oil…
I really know nothing about this problem, but I AM interested in making all things quieter. So, the idea of adding weight makes a great deal of sense for the reasons that they make the engine hug the track and the drive trains tighter to move those weights, as well as the weights act as sound absorbant inside the sound-board-like shell.
What I would like to know is, could a person also add/pad the inside of the locos with a stable (non-linting) sound-proofing material? Would it offer any benefit, or does the lead do that good a job?
Mark and Brakie, great posts!
My friend, Cmarchand, taught me the Pearl Drops method and it does work, however, I’ve had a hard time finding Pearl Drops in my area and have been looking for a substitute.
Mark-in-Utah, I’ve been playing with baking soda, but using Soft Scrub? That sounds really interesting, especially since my wife keeps two bottles of it in the house! Well, looks like she’s going to have to hide that stuff from me as it’s EXPERIMENTING TIME!
Thanks!
Another thing that you can do is open up the I.D. on the gears by .003". I cut mine with a caliper. First, I measure the factory I.D. then open the caliper to the new dimension and using the caliper, I turn the gear while it cuts the gear. I cut from both sides to even the cut. Be careful not to open too much or the gear will wobble. I also use the soft scrub to cut or run in the gears.
With apologies to Brakie, the major cause of Atharn’s noise is vibration from the motor. (It’s a cheap motor and the armature vibrates). The shell mainlly collect’s it. Sort of like cupping your hand’s and yelling. Larry, if you ever replace the motor with a better one, you’ll find this out. Adding weight to the shell merely changes it’s resonant frequency. It’s like removing opening the shower door when you are singing. The resonance is gone - but your still singing. Lining the shower with lead will change the resonant frequecy, but if you stop singing, it actually goes away.
Want proof? Remove shell . The vibration is still there. If you set the running motor on a hard flat surface, the noise returns. But don’t let me confuse you with fact’s. We differ on cause, effect, and therefor cure.
If someone want’s make it even quieter, your Item’s 2 - 10 (Gear disassembly and de- burring) are helpfull. Item 9 (hard wiring the electrical) is a major improvement - especially where grounding of the motor is concerned.