Polar Express & a pulling problem (update 12/24--towards end of thread)

[ordiei]

Hey everyone,

A very Merry Christmas to all.  And to add to that feverish pitch that we all feel this time of year with the train set smoking away, I am in need of help or advice.  Our Pol Ex was upgraded last year with the speed control and tmcc module.  Seems to be doing just fine.  Then I went ahead this year and up-ed the challenge and made a Christmas layout that runs the train three times around the tree with two grades.  The down-grade is not too bad--no major crashes yet, but the up-grade is driving me nuts.  The engine will get to a certain section and just spin its wheels.  I pulled every car off--even the engine and tender, and cleaned all the black sediment off of every wheel.  I even went and cleaned the traction tires with 409 and made sure they were working.  The first run back on the track was money--the whole train made the grade without any problems.  Then on the very next try it petered out again--just sitting static spinning its wheels.  I know the grade is probably too much, but I can't bear to tear apart the work I've done. 

So, I'm asking if anyone has any suggestions on how to improve the traction capability so that the engine doesn't just spin and spin.

 Thanks in advance for any and all suggestions.  And again, Merry Christmas to all.

Ordiei

[USNRol]

Seems like your traction tires are not in good contact with the rail heads?  My PE will almost stall the motor before the traction tires slip on FasTrack grades.  Maybe your curves are too tight?  What track are you using? Are you sure you don't have some of Sleeper's sewing machine oil on your tracks?

Roland

[ordiei]

The curves are 036 with an 036 switch--and it's fastrack.  I scoured all the track too with 409 and sanded the grades with 330 grit sandpaper (and cleaned them again .  I did lubricate all the wheels, but was extra careful about only putting a miniscule drop on each axle.

 I may resort to two traction tires--has anyone ever done this? 

Thanks for the response, Roland.

[Ted_Yor]

 I apologise if this is kind of silly. I'm new to model railroading. Does your train stall at the beginning of the grade. I noticed on the PE the traction tires are in the rear. If this is in the beginning of your grade then the rear drive wheels may not be making sufficient contact and  the front wheels making more contact and spin. When you clean the traction tires with 409 they may have swelled slightly giving you the friction you needed.

 

Hope that doesn't sound too silly. I don't know, can the traction tires be put on the front?

 

Ted

[USNRol]

ordiei

 I may resort to two traction tires--has anyone ever done this? 

You mean you only have one tire on?  My PE has both the left and Right rear main drivers tired; the other drivers do not have the recessed rim required to keep the rubber tire from riding off the rim.  You'll definitely want to put on the second tire if you're missing it now.

Roland

[Buckeye Riveter]

The Polar Express is not a great pulling locomotive and if your grade is over 2%, you are going to have problems until the percent grade is less.

The only engine I know that has one traction tire is the BEEP.  The Polar Express should have two traction tires on the rear driver wheels.  Don't put traction tires on the front driving wheels because these are picking up the current from the track.

Also, get rid of the 409.  I would not want to read a future post that the 409 has melted or warped this or that part.  Use GOO Gone, a comercial track cleaner or alcohol and a paper towel.  Wipe the track then dry the track.  Then throw away the sandpaper and use a Scotch Brite before that sand residue is sucked into a gear. (And don't ever use steel wool.) When your track begins to rust in two or three years, maybe sooner, just remember you scrubbed it with sandpaper. 

More info can be found on track cleaning by using the search feature of the CTT forum.

[ordiei]

I'm not being clear--I do have two traction tires on the rear of the engine--but it is my thought to put an additional traction tire on each rear driver to add traction.  Or maybe try to put another traction tire on one of the drive wheels.  I understand that the other drivers don't have the slot for the tire, so that might be a concern.  I see that you mention the pickup in the front wheels--so I will scratch that idea.

As for the 409, my LHS told me to use that--and it would break my heart if indeed (and I can only defer to you, Buckeye Riveter, since I've read numerous of your prior postings) if I cannot use it.  But I'd rather follow what's tried and true.

 I'll try the additional traction tire and report back.

 

Thanks again for all the good suggestions.

[hrin]

 Alcohol and a paper towel work for me.

I would be very leery of using 409 on any train related item, even track.

Are the traction tires soft and pliable? Rubber dries out esp when harsh chems are used. I hope you get it all to work for you.

[Anonymous]

How many cars do you have behind your PE? What is the rise of the grade? How many track sections between the bottom and top?

NEVER use chemicals on your trains. Most likely you need to replace BOTH traction tires. My bet would be they were damaged by the 409 when you cleaned them. Adding additional traction tires will do nothing for your PE, actually it could cause it to perform poorly on other areas of the track, if you add a traction tire to the other non-grooved wheels you will raise the other drive wheels off the track and therefore your PE will not move at all.

[ADCX Rob]

 The PE will usually stall before it looses traction.

My guess is that a grade transition is causing the problem.  The PE chassis & drivers are very rigid, and sensitive to track irregularities due to this.  If the track is flat, the PE will pull.  Try it at full speed and see if it can get past the transitions.

Rob

[Anonymous]

ADCX Rob

 The PE will usually stal before it looses traction.

My guess is that a grade transition is causing the problem.  The PE chassis & drivers are very rigid, and sensitive to track irregularities due to this.  If the track is flat, the PE will pull.  Try it at full speed and see if it can get past the transitions.

Rob

I would recommend fixing the problem! If the engine isn't making the grade by itself then there is a design problem with the track plan. Most likely the transition from the flat to grade takes place directly at a section break (which isn't the best place to do this). He most likely needs a softer transition from the flat to full grade to allow the cow prod to clear the grade transition and ensure that ALL driver wheels are retaining connectivity with the track. Diesels are a little more forgiving because their trucks tend to be closer to the front and rear.

I have had steamers short out at grade transitions because the front truck rises up and bumps the frame, also had them stall when the front truck would rise up over the track and derail, also had them stall out when pulling a load and the drive wheels would get pulled up off the track.

He has the TMCC/speed control upgrade so most likely 'running full tilt' is not an option.

[ordiei]

I wanted to give an update on the Pol Ex and the pulling problem--

I went ahead and put two extra traction tires on the rear drivers, and it seems to be doing well.  The loco pulls the cars without a problem (even though there are eight of them behind the engine).  The grade definitely is an issue and I'm making adjustments to it.  However, I wanted to mention one other victory.  I was tinkering with the observation car--I installed a blinking red led in the top of the roof where the fake jewel was, and a static white light above the observation deck.  Both came out like a dream.  It just adds a little more "pop" to the entire set.

 Thanks again to all the people who resonded.  I'm still looking into the 409 debate.  I'm gonna try my other LHS and see what I can cull from their experience.

Merry Christmas to all!!!!!