I have a problem with the set of wheels and axles I purchased for the 0-4-0.

I have spoken with the supplier and he found that the complete batch of wheels from which my set are from all have the same fault. The wheels are normally machined so they are a sliding fit on the axle seat to within 2-3mm from the axle shoulder and then pressed on against the shoulder. Excuse the quick rough sketch below but you can probably see from the dimensions that my wheels will do this but back to front i.e. with the wheel flange to the outside.

The supplier is producing a new batch of wheels and when ready will send me a replacement set. He also told me to keep the set I was sent and if I can salvage them for now or in the future then fine. My thoughts are to reduce the axle seat to allow the wheels to slide to within approx 2mm of the shoulder ready for pressing on. This would of course leave a difference of 4 thou at the outer end of the axle seat/wheel but I think the wheel would sit square once pressed against the shoulder. Also if I pressed the wheels on and used some Loctite retainer this would take up the 2 thou gap around the wheel/axle.

Hope my explanation makes sense and would be interested to hear if there is an easier/better way of dealing with it.

Regards

Ron

A couple of pics of part of the chassis and the motor drive temporarily assembled, gives some idea of how it will look. I know the rear wheel is the wrong way around, needs pressing on to be the correct way. 

Edited By Ron Laden on 26/06/2018 08:59:10

Thanks Roderick and Neil.

Neil I have just found that Noggin End Metals supply a range of brass micro channel, one of which is 4mm x 4mm x 0.5mm. A piece of this down each side channel with a tab at each end should work just fine, I will get some on order.

Thanks for the idea.

Ron

My take on some simple spring locators, turned them up from 1/2" alu. They have a 10mm spigot up into the spring with just a tad of clearance. The other end of the spring locates into a 10mm deep hole in the axle box. Spring strength is guess work so hoping they are about right, If not I have a heavier set that I can fit.

Good News/Bad News

The good news: The drive is all fitted and works very well. I was aiming for 632 rpm at the wheel for a top speed of 6 mph. On the bench the max rpm is 825 but unloaded of course so hopefully about right when loaded.

The bad news: Although the drive works well enough it is noisy and too noisy for my liking. I appreciate that I am standing directly over it and it is in the confines of a small workshop. Maybe loaded outside on a track it wouldnt be so bad or so noticeable. I am wondering if the motor mounting plate is too light, its currently 3mm steel . In hindsight (which is a wonderful thing) I am wondering if it would have been better in 6mm steel or 6mm alu. Plus the central axle bearing is an oilite, would that have been better as a ballrace.

I think I have 3 options: 1) live with it and see how it is on the track, though I am a bit reluctant to do that. 2) Un-press one of the wheels (each axle) and produce a heavier duty version of the motor plate, though this is only based on my assumption that a HD version would improve things. 3) Try and figure a way of adding something or a mod which would reduce the noise.

Will have to give it some thought, though I am pleased with the working of the drive.

Ron

Hi Jeff,

Thanks, yes the gears are from the same supplier Bearing Boys Ltd (excellent service). Both the pinion and the spur are MOD1 so the mesh should be good. The pinion is steel and the large spur is plastic and I have given them a light coat of lithium based grease. I dont know what the norm is for setting up gears but I used a thin piece of paper which measured 0.004" and placed that between the gears when securing the motor screws. I just wanted to make certain that I didnt have the gears too heavily meshed. The track I will be running on is a raised one so it will be interesting to find how it sounds.

Hi Bazyle,

The large gear is plastic and as I mentioned to Jeff I have lightly greased the gears with lithium grease but that sounds as if it is not a good idea if there is a lot of muck that could be picked up. The track I will be running on is raised, I,m guessing that it is probably a bit cleaner than ground level but I dont know. I can make a cover to shield the motors but allow a small gap to allow them some airflow.

Ron

Well, not that far from having a working rolling chassis, the chassis and parts have been primed and painted and re-assembled. I mentioned previously that the drive assembly was noisy so I carried out a couple of mods. The motor plates run on the axles and they were mounted via a 16mm long oilite bearing, I have doubled the length of the bearing to 30mm to offer more support. I have also added a nylon guide roller at each end of the motor plate to prevent any metal to metal contact when the plate moves vertically with the axle suspension.

The mods have certainly reduced the noise and it certainly sounds better than it did. I also noticed that when the drive is running a little finger pressure at each end of the motor plate improves it further. I am thinking of adding an extension spring at each end of the motor plate connected between the top of the plate and the underside of the chassis top plate. I,m hoping this will load the plate and have the same result as some finger pressure does but we will see..?

As you can tell a lot of this is trial and error and working it out as I go but one thing is for certain, it is FUN.

Pictures below:

A picture of the nylon guide roller.

Thanks Neil

I must admit I am enjoying it.

Ron