It's dc and non sound. (Sorry but I'm old fashioned and started well before dcc!)
It's a great runner but a noisy one!
Does anyone have any ideas?
Thank you in advance.
My thoughts without answers. At a certain speed the chatter starts on both of mine, less in reverse. I've left one unaltered and have heavily messed around with the other one, 3004. I thought perhaps the motor was to blame but with a Mashima and non accurately bored out worm the noise was worse. I've had other variations of motors like custom skewed OEM and NWSL both using stock unaltered worms and the the chatter still exists above a certain speed.My Wombat 30T is back in its box, I took it out only to have a bopeep, and take the tail rods off the cylinders as mine is a Superheated version which did not have them, and I have not tried to run it yet.
There is tape underneath the OEM motor which I thought may dampen vibrations and I have experimented with a layer of squished blu tac and other tape to no avail. Then there are those four metal plates which I can't remember off hand exactly where they go, but I think they go between the sides of the metal gear housing and the body, and they might dampen noise. But from memory there was still noise before I took them out so i haven't put them back in.
Then there's the gears. I've only once disassembled everything. The worm, worm gear, reduction and drive gears (not sure of exact names), they all seem finely machined and mesh really well and the chassis finely machined to accept shafts in the right spots. I really can't tell where the chatter comes from except to say I think the gears cause the noise but I don't know where or why.
I've thought that perhaps fewer gears would make a difference. I've an unassembled FSM Z25 kit that has a fine pitched worm and drive gear without idlers. I look forward to seeing if that type of setup is noiseless. On the other hand a Lloyds C30 with worm, idler and drive gear in a NWSL gearbox is smooth and quiet. The major difference is it drives the middle axle which makes the gear box visible. So in that respect the Wombat does well to conceal the gears and any attempt to change the gears to a more direct drive setup would require major and accurate work I'm incapable of.
So I don't know. I'll have another look at this one day but the only thing I'd be prepared to do myself that probably goes against any advice of the more experienced and manufacturers is to liberally apply heavy grease to the teeth of all gears. I'm not recommending you or anyone to do it, but I'll give it a shot for the greater good. Soon.
Did a fair bit of testing over the weekend, results were negligible. I used INOX MX6 and MX8 on two mechanisms a 30T and Ixion 32. Briefly about the greases - MX6 food grade type, is synthetic PAO with PTFE. MX8 is lithium based with PTFE and much thicker.Oscar, looking at the last pic, I gather the gears are some sort of synthetic/nylon or something rather than brass gears that were more common in previous models as I have not purchased anyloco's for some time, the Wombat 30T being the exception, I wonder if brass gears may be better? Other thing I notice and maybe the photo's angle but the 3rd pic looks to me with the large gear to have minimal distance between the side of the gear and the metal side of the chassis/gear setting, could that mean the noise could be the gear rubbing against the metal, as the model increases speed?
The 30T always had a quieter spot which I said was around quarter throttle but after remapping the chip to a straight line to mimic a lineal DC like response, I discovered the mechanism was quieter between 50 - 90% throttle. I used MX6 first which had no effect. After trying to remove some I repacked the area with MX8 and whilst I thought there was some improvement, now I'm not sure.
The 32 had just MX8 applied, repacked twice and it made no difference. The 32 has the gear noise form zero to full throttle.
I videoed and compared everything but they don't capture what you can hear. It's a bit of hit and miss and sometimes unfairly exaggerated so I've not cut a video together. In short, overpacking with grease didn't really improve anything.
I will leave some photos of the mechanisms though because there's one more thing I'd like to try.
Before I greased the mechs I took photos of them just to check they were the same.
The 30T had a little more factory grease compared to the 32 but both were lubed enough IMO. With them appearing the same I wondered why they sounded different. The idler in both mechs can slide laterally and the 30T's idler could move more readily compared to the 32. Perhaps the 30T is more run in. But I would like to try and see if adding bushings, washers and a spring to keep the idler in place will make a difference.
The first two pics show the 30T with idler in different positions and the last is of the 32 showing the same gear arrangement. Helical cut gear and attached reduction are easily visible in the last pic.
I can't believe that Nylon gears would be noisier than brass. I am also not surprised that packing grease makes no difference.Sugestion only
I have a re-motored Ixion C32 (similar mech to Wombat C30T) and it is quite noisy, particularly in reverse, but otherwise runs well since fitting a Mashima motor.
If there is a significant difference in noise between forward and reverse then one must suspect the helical gear that meshes with the worm, this will be thrust either left or right depending upon the direction of travel.