How difficult is it to ADD ball bearings to axles?

A lesson learned at Right of Way....

All of the passenger cars have roller or ball bearing axles.  Make a note that unless your roller pickups are precision made, they will drag to the point of loosing the benefit of the bearings.

Lou N

instead of ebay,

vxb bearing.com,

http://www.bocabearings.com/

Is another good source for ball bearings. 

There are different types as well as sizes.  There are open, or unsealed, semisealed and fully sealed.  There are flanged and flangeless.  There are stainless and regular steel and ceramic.  There are two ways they are described, one by dimensions and the other is more thorough but I have yet to decipher it.

The bearings I get are 2x5x2.5, that's inside diameter (the diameter of the axle) the outside diameter (the diameter of the hole they fit in) and the width of the bearing; all in millimeters.  The other way those are described is MR52ZZ and that describes the other parameters described above in addition to the ID and OD.  In this case semisealed, stainless and flangeless.

As far as installing them drilling the hole to place the bearings in is a pain but turning down the axles and reinstalling and reguaging the press fit wheels on the axles with 2mm ends is a real PITA unless you make yourself some type of pusher.

A far easier mod would be to remove the center track rollers and use a tether to connect the cars.  At least half the drag is due to the center rollers, and you can fix that easily.  Putting bearings in all those cars would be a trick!

gunrunnerjohn posted:

A far easier mod would be to remove the center track rollers and use a tether to connect the cars.  At least half the drag is due to the center rollers, and you can fix that easily.  Putting bearings in all those cars would be a trick!

John,

If I understood you correctly, I think this would also eliminate flickering. For example, if the cars have two pick up rollers, one roller could be removed from each car (or more rollers could be removed) , the cars would then be connected together with tethers, and thus drag would be reduced, and electric pickup spread out for all the cars. Good idea!

Alex

You could actually remove all but a couple of rollers in the whole consist and with LED lighting and capacitors, no flicker at all and very easy rolling resistance.  I saw someone that tethered the locomotive and didn't have any rollers on the passenger cars.

can you recommend a certain type of connector to use between the cars?

If you do LED lighting, I'd use the Minitronics mini connectors, they look like they belong there.  They're good for an amp, plenty for LED lighting a whole train.  The two pin one would be just dandy.  If you make sure they're all in the same orientation, you can add and drop cars at will and the others will all connect.  I'd probably just leave the rollers on one car, perhaps the observation car, it'll probably be with the train as a rule.

Not worth doing.  Turn the transformer up.  I have a few cars and would not do bearings.  Most of what we have today has plastic bearings and they do well.

Marty, I think he's specifically targeting the MTH Aerotrain, those cars seem to have excessive rolling resistance for how small they are, not to mention only having single axles.  They just have more rolling resistance than most cars.

John, I know you have that set.  When you ran it in New Jersey it seemed to roll smooth.  I do not have one to look at but I thought it had the plastic bearings. on the wheels.

I used JST connectors to gang all the cars (and loco) electrically together.  You can get ten pairs for ten bucks from Amazon.  I also dramatically dropped the rolling resistance by dispensing with MTH bearings, and inserted brass tubes into the truck side frames.  I then used wheel sets with pointed axle ends to fit into those brass tubes

Marty Fitzhenry posted:

John, I know you have that set.  When you ran it in New Jersey it seemed to roll smooth.  I do not have one to look at but I thought it had the plastic bearings. on the wheels.

It runs fine, but when I put all ten cars on the track and pull them manually, you can see that it's more of a load than you'd expect.  No plastic bearings, they have bronze sleeve bearings like a powered diesel truck. 

I took an 18" Premier car and a new AeroTrain car, lined them up on parallel tracks and gave them a little shove letting go at the same speed.  The 18" car went twice as far as the Aerotrain car.  I swapped tracks to eliminate any issue with track specifics and got the same result.

FWIW, the 18" passenger car also has bronze sleeve bearings, and six wheel trucks, don't know why the Aerotrain cars have so much friction.  I oiled the Aerotrain car and ran it around for a couple of laps, then tried the test again, same result.

I then took of the center rail pickups and repeated the test.  The Aerotrain car did better, but the 18" Heavyweight still easily walked away with the prize.

Very strange...

John Sethian posted:

I used JST connectors to gang all the cars (and loco) electrically together.  You can get ten pairs for ten bucks from Amazon.  I also dramatically dropped the rolling resistance by dispensing with MTH bearings, and inserted brass tubes into the truck side frames.  I then used wheel sets with pointed axle ends to fit into those brass tubes

Not on the Aerotrain cars you didn't.  The "sideframes" are a cheap skinny plastic overhang that's strictly for show.

gunrunnerjohn posted:

John Sethian posted:

I used JST connectors to gang all the cars (and loco) electrically together.  You can get ten pairs for ten bucks from Amazon.  I also dramatically dropped the rolling resistance by dispensing with MTH bearings, and inserted brass tubes into the truck side frames.  I then used wheel sets with pointed axle ends to fit into those brass tubes

Not on the Aerotrain cars you didn't.  The "sideframes" are a cheap skinny plastic overhang that's strictly for show.

Yes I did.  And the sideframes are not plastic on my set.  Car on the left is original, car on the right is modified with aforementionned brass tubes embedded in truck side frames.  Yes, I used 2 rail wheel sets, but you can do the same with 3 rail wheel sets. All nine cars have been running this way since February 2011.  

i've considered putting bearings in a 3551 Marx cast metal tender.

there seems to be two price ranges of small bearing... $3-$6 (Chimport) or $10-$12 each.

Within the limits on the draft to accomplish mold or tooling release, these wheels appear to be flat tread wheels.  That is, not fast-angle wheels... and I once did an analysis on such wheels, and found that the available gage play would only allow fast angle wheel to act as intended on curves of O-54 and flatter.  I forget whether that was with 0-27 rail or the higher O rail, but it was on tubular Lionel rail.  Normally I would have used a back-to-back of the wheel set of 1.07" for short wheelbase Lionel truck.  I think I would have been looking for results on "O" track, which has the narrower gage (by 0.03"), but I'd have to find the drawing.

Anyway, even if it would work, on a curve the drawbar pull wants to pull the flanges against the low rail and negate the fast angle effect.  In real life, the centrifugal forces can overcome this with sufficient speed, but centrifugal forces do not scale down in the same way in the model.  Then, when against the inside rail, there is the effect that every added car increases the flange friction force of every car ahead of it.  It depends also on the total angle of wrap on the curve and the sharpness of the curve, and the increasing effect has a  logarithmic increase... calculating this being once of the classic textbox problems of high school math.  The old rope around the bit to hold a boat to the dock problem.

Remember Lionel saying that their multiple unit diesels would pull better if the motorized A unit ran backwards next to its train, pulling the cars, and pushing the dummy diesel units?  Lionel didn't say why, but it was to counter the wrapping effect on curves.  Solid axles lead to increases in this problem, while roller bearing will not totally cure it and probable are not much of an improvement over the old postwar style of wheels not fixed to the axles (smooth bearing) when lubricated.

Someone once offered a service to retrofit roller bearings to the fast-angle wheel sets of the MPC reintroduced 15" aluminum passenger cars.  Their pointed axles also cut upward thru the cylindrical pockets in the postwar sideframes designed for the plain axles used in postwar. Perhaps the service had old axles available, but the roller bearings required a pocket machined into each of 8 existing wheels and disassembly of the swaged truck frame.  That at least doubled the cost of a painted car.  So I never tried this out, and can't say if it solved the problem to a sufficient degree.

--Frank

I stand corrected John, I looked closely at an Aerotrain car and they are metal side frames.  That looks like WAY more work than makes sense, but I'll bet it did improve the rolling resistance.  You obviously went to the trouble as you needed to change the wheels anyway.  However, folks that run 3-rail aren't likely to go to that extreme.

Can you point me to the "JST Connectors" you used?  JST has a very large and diverse product line.

gunrunnerjohn posted:

I stand corrected John, I looked closely at an Aerotrain car and they are metal side frames.  That looks like WAY more work than makes sense, but I'll bet it did improve the rolling resistance.  You obviously went to the trouble as you needed to change the wheels anyway.  However, folks that run 3-rail aren't likely to go to that extreme.

Can you point me to the "JST Connectors" you used?  JST has a very large and diverse product line.

GRG

Actually it was straightforward, but you do need some machine tools.   A simple jig aligns drilling the hole for the tube.  The jig is an ""L" shaped piece of aluminum, lying long face down.  The vertical part has threaded holes to screw the sideframes into. The holes are oriented so the outside face of the sideframe rests on the horizontal surface.  You can use a mini drill press for this part. Once you make the jig, drilling the hole is a five-minute-per-sideframe job 

If you want to neatly cut back the truck blocks, as I call them, you need a mill.  (You can see the bare metal where I removed material.)  However, you can skip this step entirely by pulling one wheel off the axle, threading the axle through the truck, and then pressing the wheel back on.  You have to purchase wheel sets, because the MTH ones don't have ends

As for the JST connectors, I did not know there were multiple choices. I use these:

http://www.amazon.com/pairs-JS...Female/dp/B0089RAXB2

I have used these in may applications to improve pick up.  As I maintianed pick up from my Aero train coaches, The entire nine car train has 24 wheel pick up.  The beauty is you can thread them through the dia[phrams so they don't show:

While they're more expensive, I prefer the Minitronics connectors, those are huge compared to the ones I use, and also the red kinda' stands out.

The fact that it requires machining as you describe puts it out of reach for most folks.