Westside Q4b Traction Issue

check that the downward force exerted from the leading and/or trailing truck springs is not applying to much force. This can reduce traction because it reduces the weight on the driving wheels.

Drivers are probably plated.  Run it for an hour under light load, then try again.

Just to make sure, touch a magnet to those tires to make sure they are carbon steel under the slippery chrome or nickel.

I have had to double head mine up anything more that a 2% grade. You could add more weight as there is room. I have a few extra if you are in the market :-)

How steep is your grade?  I know this doesn't address your concern, but in real life, I doubt a Q-4b would be rated more than 13 cars on a steeply-graded division.

the grade in question is a little under 3%.

these locos have been known to be troublesome in many ways.     One is that they have narrow tires compared to most O scale 2 rail.    Another is cold solder joints.     However, these would not affect traction.  

One thing to look at is that all 8 drivers sit on the rails.    Sometimes something is cockeyed.    if all are not on the rails, perhaps some changing out of springs might help.     this can usually be done on locos by removing the bottom plate without removing the rods.    You can  often change out all the gearbox axle ones that way.  

The plating may be an issue as mentioned - since that would be slipperier than steel.     However, if the wheels are brass and not steel removing the plating will worsen the electrical pickup and may not be worth the gain in traction.    

Another issue is the weight and rolling behavior of the cars.     the Atlas Fishbelly cars weight 2 lbs (give or take an ounce or 2)  and make a really heavy train.   I have gotten rid of mine for this reason.    The MTH fishbellys are equally nice and not nearly so heavy.     On the MTH and Sunset cars, do the trucks roll freely?    Will the cars roll down the grade if uncoupled?    If they don't you may want to change or work on the trucks to make them more free rolling.

And as mentioned that is a steep grade for mainline, so why not a helper or double head or double the hill?

I personally would not add weight to the gearbox since that might stress it and tear up gears.

Thank you all for your responses! I'll try and address all of you thus far.

David Eisinger posted:

check that the downward force exerted from the leading and/or trailing truck springs is not applying to much force. This can reduce traction because it reduces the weight on the driving wheels.

The downward force is actually ok. I've had an issue with the pilot truck jumping the rail before and it's all good now. The rear truck was checked too and it's fine.

bob2 posted:

Drivers are probably plated.  Run it for an hour under light load, then try again.

Just to make sure, touch a magnet to those tires to make sure they are carbon steel under the slippery chrome or nickel.

I'll check that next time I have her out! I didn't realize they could plate the wheels.

prrjim posted:

these locos have been known to be troublesome in many ways.     One is that they have narrow tires compared to most O scale 2 rail.    Another is cold solder joints.     However, these would not affect traction.  

One thing to look at is that all 8 drivers sit on the rails.    Sometimes something is cockeyed.    if all are not on the rails, perhaps some changing out of springs might help.     this can usually be done on locos by removing the bottom plate without removing the rods.    You can  often change out all the gearbox axle ones that way.  

The plating may be an issue as mentioned - since that would be slipperier than steel.     However, if the wheels are brass and not steel removing the plating will worsen the electrical pickup and may not be worth the gain in traction.    

Another issue is the weight and rolling behavior of the cars.     the Atlas Fishbelly cars weight 2 lbs (give or take an ounce or 2)  and make a really heavy train.   I have gotten rid of mine for this reason.    The MTH fishbellys are equally nice and not nearly so heavy.     On the MTH and Sunset cars, do the trucks roll freely?    Will the cars roll down the grade if uncoupled?    If they don't you may want to change or work on the trucks to make them more free rolling.

And as mentioned that is a steep grade for mainline, so why not a helper or double head or double the hill?

I personally would not add weight to the gearbox since that might stress it and tear up gears.

I could write a book on the issues with this locomotive... I love it though. Geoff Ringle at Old Iron Designs did a fantastic job with it after the coal bunker fire. The locomotive is battery on-board so powered pickup isn't a priority for me.

The rolling behavior of the cars is something I took a look at during the session. The consist was 5 boxcars (Atlas, 2 Sunset, 2 MTH), tank car (Atlas), 2 flat cars (2 MTH), 3 reefers (3 Atlas), 3 hopper cars (3 MTH) and I-12 (Sunset). On flat track mind you the locomotive did fine. The sunset M-53's have high rolling resistance and weigh a good bit. I took them off the train and it still had issues going up the grade. I took the flats off which roll ok but not perfect and still had trouble. I got down to 8 cars and still couldn't get up the grade.

Nick,  My steepest, long grade is about 2 degrees, which is what it is suppose to be and I checked it with a phone app.  I put 15 cars behind my duplicate of your engine and got the whole train on the grade.  I turned momentum off on the decoder and zipped up to speed step 28.  It ran up the grade with no slip.   I get a little slipping at 18 cars and a little more at 20 but it still runs up the grade.  Train was made up of Atlas cars and included 6 die cast hoppers. 

Any chance that the boiler weight was removed or shortened during the conversion?  Are we sure it had a weight in the boiler when you got it at Strasburg?  My engine alone weighs 5 pounds 10 ozs. 

 Can you add a couple ounces on top the boiler temporarily to see how it resonds?  Like maybe lead tire weights wrapped in a rag ...made up like a saddle bag slung over the top?  

Just remember the old rule about adding weight.  Learn how many amps the existing motor is rated for, and make sure the wheels still slip at maximum rated current.  If there's so much weight that the wheels can't turn, you need a more powerful motor, lower gearing, or less weight!

Also... I want to hear more about the coal bunker fire.  Sounds exciting!!

astarr posted:

Nick,  My steepest, long grade is about 2 degrees, which is what it is suppose to be and I checked it with a phone app.  I put 15 cars behind my duplicate of your engine and got the whole train on the grade.  I turned momentum off on the decoder and zipped up to speed step 28.  It ran up the grade with no slip.   I get a little slipping at 18 cars and a little more at 20 but it still runs up the grade.  Train was made up of Atlas cars and included 6 die cast hoppers. 

Any chance that the boiler weight was removed or shortened during the conversion?  Are we sure it had a weight in the boiler when you got it at Strasburg?  My engine alone weighs 5 pounds 10 ozs. 

 Can you add a couple ounces on top the boiler temporarily to see how it resonds?  Like maybe lead tire weights wrapped in a rag ...made up like a saddle bag slung over the top?  

...  ...

Mark in Oregon

astarr posted:

Nick,  My steepest, long grade is about 2 degrees, which is what it is suppose to be and I checked it with a phone app.  I put 15 cars behind my duplicate of your engine and got the whole train on the grade.  I turned momentum off on the decoder and zipped up to speed step 28.  It ran up the grade with no slip.   I get a little slipping at 18 cars and a little more at 20 but it still runs up the grade.  Train was made up of Atlas cars and included 6 die cast hoppers. 

Any chance that the boiler weight was removed or shortened during the conversion?  Are we sure it had a weight in the boiler when you got it at Strasburg?  My engine alone weighs 5 pounds 10 ozs. 

 Can you add a couple ounces on top the boiler temporarily to see how it responds?  Like maybe lead tire weights wrapped in a rag ...made up like a saddle bag slung over the top?  

I'll weigh it today. It may just need more running time. It was in very good, almost mint, condition when I bought it. 

Ted S posted:

... Also... I want to hear more about the coal bunker fire.  Sounds exciting!!

I'll write a post someday about that once I figure out how to post pictures properly! It's a funny story.

rattler21 posted:

Nick,  Not on this subject but if you want to list items FOR SALE you may consider showing an Internet address at which potential buyers could contact you.  John in Lansing, ILL

Thanks for pointing that out! Just updated the post. I figured people would find my email in my profile. Also I’ll have an update on the traction of my engine soon. I’ve done some testing. 

Stay healthy everyone!

 Nick

Narrower than NMRA standard drivers.

That in itself should help identify less traction. There is a smaller 'footprint' for each driver on the rails than it would be if they were wider.  Also an affect would be the gauging of those narrower drivers, which on some Westside locos from the late 1970's was narrower than NMRA standard, set to what was "PSC Gauge" - an early attempt to 'correct' the  error of a 5' gauge in O gauged track. Not quite P-48 gauging either,  but that too reduces wheel tread contact when run on NMRA standard  O gauged track.

I have a Westside B&O 'modernized' P-7c which I reworked to a P-7e with more accurate detailing and a large, 12 wheel Sunset, tender as seen below. It has narrow drivers and I widened all the wheels to NMRA standard. Doing that required re-hanging the valve gear and installing neoprene spacer washers on the driver axles to take up the added side play from wider re-gaugung.

On a 2.5% grade with its original weight, Canon motor an drive, it can ( with careful throttle use) start a five car passenger train of mixed American lightweight and Walthers cars without undue slipping.  With six cars, it slips.  B&O in using its P-7 locos on the Cincinnatian and other trains over the mountains limited them to a 5 car train for much the same reason. So in some respects, my model's limitation is reasonably prototypical.   

In prototypical operation in the days of steam,  the selection of power for a train and its tonnage depended as much on the weather as it did the number of cars. What an assigned loco could do on a warm, dry day could differ from what was able to handle with the same assignment in wet or freezing cold weather.

S. Islander

Gauge will affect tracking, but not tractive effort much.    If I remember correctly the wheels are still wider than the railheads, so wider wheels would not add traction.

Balance is another issue.    The engine should be weighted so it would sort of balance between the middle sets of drivers.    this does not and cannot be exact, but try set it on a large dowel or wood rod set between the middle drivers and all wheels off the surface.    It should not strongly fall the to the front or rear.    Again not exact but too heavy on one enc should be obvious.     IF so move the weight to get better balance.

Another problem sometimes is that all wheels do not set on the rail.    One wheel or axle may be very slightly high due to some mfg fault.    Try sliding a piece of paper under each driver with the loco setting on rails.   slide it  under the tire sitting on the rail, not flange.    You should NOT be able to do this.   If you can slide the paper  under a driver, it is not touching the rail and you are loosing traction.    Then you need to work on getting it down to the rail.

I always get in trouble here.  I think it matters not how many drivers are actually in contact - if the weight is over the drive wheels (balanced is good) without any reduction due to lead/trailing trucks or drawbar, then if one driver lifts, the weight is shifted to the others.

I used to be freaky about sprung drivers, but after testing a number of early models (Scale Craft, Lionel, Ferris, etc.) I discovered that springing does very little in the way of performance enhancement or tracking.  And my track sucks - plus I have extreme superelevation on the outer loops.

Even Proto-48 drivers have the same rail contact as the 172s, but there, as I understand it, you run into trackability problems, and most go for slightly wider steam drivers.  Not sure if that is still true - but I couldn't keep a 115 caboose on the track.  My minimum width is .155; Sunset's standard.

A bent vertical or droop/bow/angle a drawbar can throw off pulling balance too.

More wheel width on the railhead should increase traction on good track*; no doubt there for me; more area planted on = more friction; i.e., it's more traction. It boils down to # per sq. inch planted , and "balance" (angle(s) applied)

Gauging wide helps imo. Energy is lost to excessive banging off the left and right. More wiggle space increases possible lateral momentum/inertia; i.e., allows harder bangs. Harder banging means a better chance at climbing too. Not to mention the flange rub can do a little pull work when rubbing  (think of better V belt traction over flat band drive pulleys.)

If we ran 200 miles, true, flat, smooth, & straight ahead I'd gauge a little narrow to reduce drag   But as wide as possible without binding in curves is my norm.

* track brand/ railhead shape/ code? That may cause a difference comparing your's to other's locos too.

You can look at car or bicycle tires for the width examples too. Low drag, super skinny racing tires for more efficiency(dragster front&ten speed), and fatter ones for traction (dragster, mountain bike).

I’d like to apologize for the novel I’m about to compose.

The issue this locomotive had is with puling power. That’s what this thread is about after all. However, there were also issues with tracking in general. Now, I know people have talked to me about Westside models having narrow wheel bases, P48 wheel bases, and thin tires. However, my locomotive was coming off the rails for a different reason.

I took the locomotive to a friend’s layout. He was kind enough to take a look at it since he has two WSM Q4.b’s. When we compared the wheels, mine were significantly shinier than his, indicating plating. I ran the locomotive in on his layout, as well as another friend’s who was kind and allowed me to come over. The plating has worn down some, and traction improved on straight track. When running the locomotive, we noticed something odd… the wheels were off the rails on sharper curves and steep grades.

David said to check the downward force on the leading and trailing wheels to make sure all sat on the rails. He was right on the money, but it wasn’t downward force causing issues; it was lateral forces. In the “close” or “narrow gap” hole in the drawbar, we found that the cab roof will ride up the forward end of the coal bunker and lift the trailing truck and rear two drivers off the rails. Anyone running on DC/DCC will know this causes a short. As a deadrailer, I never had this problem and never even thought to address this possibility. This was compounded by a different issue with the leading truck. The short coupler box (743 plastic box) would get hit by the cast springs on the leading truck when going around a curve of 52” radius or smaller. The axel itself would hit the box going up a grade as well. The way the leading truck is designed causes the front two drivers to lift off the rails. So effectively what has been happening is the driving wheels were lifted off the rails by tension from the front and trailing wheels, leaving no driving wheels on the track.

To fix the rear trucks lifting, I moved the position on the drawbar from the close to the far hole. The far hole is a bit too far for the deck plate to drop, so I will make a custom drawbar at a later date that fits in the sweet spot. To fix the leading truck lift issue, one of my friends tapped a center mounted screw on the model. Then he shaved down a plastic coupler box to hold the coupler in place.

The locomotive started performing better on tight curves immediately, and performance on grades improved as well. For those keeping score on Atlas track, these modifications allow this engine to take Atlas 49.5” radius curves. God help you if they’re sharper than this… We got a train of 18 cars up the 2(and some change)% grade. I’m sure with a little more modification that performance could improve.

I’m exploring the possibility of a new pilot that would be more prototypically correct. This could move the coupler housing away from the lead trucks all together. I also will add some weight to the engine. Another friend of mine has KTM locomotives that are about the same size and weight upwards of 15-25 pounds. Mine weighs in at 7lb 10oz. I want to see if I can get her to at least get 10 pounds (total weight, not additional) and adjust the decoder for the difference. I know this may stress the gears, but I’m hoping the fact I have momentum on will help reduce wear.

The one drawback with battery power is the extra weight will affect the runtime. I got roughly 2 hours off of a battery that sat stationary at a train show two weeks prior with some running, being on 8 hours a day for two days, all on a single charge. I’m not too worried; I’ve gotten really good running time out of her.

If you made it this far, thanks for reading! Regardless of these issues, I’m really starting to dig into the hobby and am enjoying it immensely! Thank you all for your suggestions; I looked into each of them and they all helped in one way or another. Stay safe during this pandemic!

TL;DR: If you’re wheels aren’t on the track, you’re not pulling much.

Here is what I'm talking about. I forgot I had this video, otherwise it would have been in the post above.

Here is the performance after fixing those issues. This railroad has 3.5% grades on it and was lapping it like a champ.