Wheels & how to remachine them.....

[tramcar trev]

I did a search to see if there had been any discussion re this before... My curves are tight and trams derail on them with monotonous regularity especially now where the flanges can climb on the stones laid between the tracks. I am thinking that machining the Bachmann flanges would help and making them more of a "gauge 1" profile with a radius edge to the flange rather than the razor sharp edge there now.....
Has anyone done this? I'm in 2 minds dismantle everything and put the wheels in a lathe with a profile cutter and take of a skim or turn each car upside down, power it up and address each flange with a flat needle file while rotating....
Thoughts?

 

[dunnyrail]

Trev, not 100% certain but I think that you should have opened up the Gauge slightly on the curves to say 46.5 mm track Gauge. If you do indeed need to lift track try this out to see if derailment issue is resolved. Also look at widening gap on the gap between Stones and Rail again because the back to back between sets of wheels will catch the Stones. Perhaps you could dummy up an open chassis that would match the Chassis Wheel Base and push it gently round the curves to observe what is going on. On second thoughts strip out the chassis from a Bachman Tram and gently push it round, you should be able to see the problems with close observation.
Good Luck,
JoD

 

[trammayo]

You have a prototypical problem Trev. Even on the 12" to 1'0" lines, on grooved track, curves need a wider groove. I've never removed the wheels on a Bachmann truck but do know older wheels can wobble (down to deterioration of insulated centre?). The wheels are largish (probably representing 30" dia.) so any reduction in flange diameter should help.

Filing them might be an option (rather than removing them off the axle) but, even then I'd take them out of the block and do it on the bench top rather than chuck them because I'd be concerned about the insulated centres. You could chuck the axle assembly by the wheel tyre if you can get in close enough with a tool (or file) and then turn it round to do the same. I suppose patience is the name of the game.

You could make your own trucks (shorter wheelbase) or make them into bogie cars.

 

[dutchelm]

My trams run around tight radii but I needed to widen the gauge to 47mm on tight corners. LGB trams are no problem but the wider flanges on Bachmann catch on the check rails & I am wondering about thining the flanges, and how to do it>

 

[MRail]

Trev, in my former existence with the Tramway & Light Railway Society, we built our cars to 1/16" scale and ran on 3½" gauge track. Our local portable track was never actually paved up, looking more like a spidery railway siding.
One of the "Gurus" in this field advocated tapering the back of the wheel over the flange edge, so that it gave a radiused profile to the check rail or paving, thus easing passage.
The radius was continued round the flange face, so that it was rounded rather than sharp.
Gauge widening was widely(!) used, as others have mentioned.
Ballast weights can help.

 

[Dtsteam]

I've heard this idea of tapering the back of the flange and radiusing the tip as well. It also serves to reduce the depth of the flange slightly, but its a subtle adjustment. It may be worth trying simply because it allows you to chuck the wheel by the tyre.

 

[bobg]

Speaking ? Writing ? Typing with my 7 1/4" hat on, we make full use of gauge-widening and I would agree that flanges should have a mildly rounded profile so they do not 'attack' the check-rails. The depth of flange should not be reduced too much unless you are certain of your track laying, because if there is somewhere where only three wheels are in contact (lack of suspension movement) then it may just pop out if the flange on the other wheel clears the rail. From experience, most derailments are caused by poor gauge and/or back-to-back measurement. Sufficient weight can also be a factor.

I like the idea of a 'test truck' that has visibility through to the wheels.

 

[tramcar trev]

Having taken all this aboard (as it were) I looked a bit closer. Ok I should have looked before.....You can each deliver 50 lashes with a wet tram ticket...
The OLDER Bachmann wheels are the problem as are the existing AMS wheels (as used on the cable car that I converted). My proposed mod is in the red ink and this will bring it more or less into line with the NEW Bachmann profile on the right with which there are no problems at all. I must remember to look more closely in future, The converted cable car is on bogies and was having all sorts of strife, the older Bachmann single truck cars like wise, the new Bachmann cars had no problems.
I didn't use a test truck instead opting for a dental mirror and slow speed and indeed the flange catches on the cobblestones and climbs off the rail, the wheels with a radius don't climb....
I'll make up a profile cutter (to the shape of the new Bachmann) and reprofile the old Bachmann wheels and the AMS wheels, they can, as has been suggested, be gripped by the tyre to do it....