My EM-1 blew a tire

[Maletrain]

I was testing my new Bachmann EM-1 to see how it would do pulling at train that I bought it to pull.  It is 55 hopper cars.  It seemed to pull them fine on a level oval without any detectable wheel slip.  I wanted to see if it can pull that train on a 1% grade, so I stuck a 1" riser under one end of my 9' long test loop, and it did not seem to slow the beast at all, with no apparent wheel slip.

But, on the 2nd lap with the grade added, I noticed a traction tire had torn and was hooped around the rods, with the loco's performance still showing no ill effects.

I suspect I overloaded it, but am wondering if it was weak to begin with.  The other 3 traction tires seem normal, at this point.

So, I am wondering how to replace the tire.  Or, if I should just go the Bullfrog Snot route.

Recommendations on the choice?

Any guidance on how to get the wheel free to change the tire?  I do not see any screw head on the fastener connecting the rod to the driver.  Is it a pin that pulls out to the side?  Does pulling it out once tend to make it loose so that it tends to come out later when running?

[Mike C]

  This may work .....Put a light coating of Bullfrog snot in the TT slot . Then carefully thread the old tire around the wheel .  Use just a small bit of snot on the broken ends of the tire .     Mike

[robert3985]

I was testing my new Bachmann EM-1 to see how it would do pulling at train that I bought it to pull.  It is 55 hopper cars.  It seemed to pull them fine on a level oval without any detectable wheel slip.  I wanted to see if it can pull that train on a 1% grade, so I stuck a 1" riser under one end of my 9' long test loop, and it did not seem to slow the beast at all, with no apparent wheel slip.

But, on the 2nd lap with the grade added, I noticed a traction tire had torn and was hooped around the rods, with the loco's performance still showing no ill effects.

I suspect I overloaded it, but am wondering if it was weak to begin with.  The other 3 traction tires seem normal, at this point.

So, I am wondering how to replace the tire.  Or, if I should just go the Bullfrog Snot route.

Recommendations on the choice?

Any guidance on how to get the wheel free to change the tire?  I do not see any screw head on the fastener connecting the rod to the driver.  Is it a pin that pulls out to the side?  Does pulling it out once tend to make it loose so that it tends to come out later when running?

Whatcha mean by "torn"?  Is it actually "torn" or has it just come loose and worked its way onto the rods?

If it's "torn", then I'd replace it with a stock Bachmann part, which (after looking at photos of the model) shouldn't be all that difficult to do...securing it with a bit of canopy cement...a very little bit, cleaning both the new traction tire and the metal tire it fits on with Bestine (Heptane). 

If it's still good, do the same thing, but again, take some Bestine (Heptane) and clean it and the tire it goes on to get rid of any grease...then re-attach it using a bit of canopy cement to secure it.

That should do the trick. 

Cheerio!
Bob Gilmore

[Maletrain]

Bob, The tire is not intact.  It has a clean-looking break perpendicular to the wheel radius.

I am careful putting locos with traction tires on the rails, so as to not stress the tires.  My techniques is to use one of those blue Kato railers, putting the loco on it and moving the front onto the rails, then holding the loco still and pulling the plastic railer out from under the loco instead of shoving the loco along the rails.  That should put any stress on the flanges against the plastic instead of on the wheel treads (and traction tires) against the railheads.

In this case, there are a lot of wheels, but I am pretty sure that I started sliding the plastic before the now-busted tire got to the rails.

So, this seems to be due to the stress from pulling the train. It occurred on a wheel on the inside of the loop curves, which makes sense as the higher stress side.

If I use a traction tire again, I will use an unbroken one.  The question is how to get the wheel disconnected from the rods, and whether doing that will lead to it coming loose when running after I put it back together - especially if I make a habit of killing tires with this loco on long trains and need to replace tires more than once.

The other option is Bullfrog Snot, which does not require removing the wheel.  Does that work well enough to make it worth putting on?  Or would it be almost as good to just run with the tires missing?

[robert3985]

Bob, The tire is not intact.  It has a clean-looking break perpendicular to the wheel radius.

I am careful putting locos with traction tires on the rails, so as to not stress the tires.  My techniques is to use one of those blue Kato railers, putting the loco on it and moving the front onto the rails, then holding the loco still and pulling the plastic railer out from under the loco instead of shoving the loco along the rails.  That should put any stress on the flanges against the plastic instead of on the wheel treads (and traction tires) against the railheads.

In this case, there are a lot of wheels, but I am pretty sure that I started sliding the plastic before the now-busted tire got to the rails.

So, this seems to be due to the stress from pulling the train. It occurred on a wheel on the inside of the loop curves, which makes sense as the higher stress side.

If I use a traction tire again, I will use an unbroken one.  The question is how to get the wheel disconnected from the rods, and whether doing that will lead to it coming loose when running after I put it back together - especially if I make a habit of killing tires with this loco on long trains and need to replace tires more than once.

The other option is Bullfrog Snot, which does not require removing the wheel.  Does that work well enough to make it worth putting on?  Or would it be almost as good to just run with the tires missing?

Y'know...if it pulls your train and doesn't struggle up your grade, then I'd just leave it off.

Yup, pulling a locomotive on the rails with the drivers remaining stationary is probably the main cause of causing traction tires to break.  Kato GS-4's and FEF-3's are particularly tempermental that way.  I'm sure others are too, but I learned the hard way with those two models.

When looking at photos of the Bachmann model, it appears the pins holding the rods on have a hexagonal head, and also a screw/slot head.  I would assume this means that they can be unscrewed with the right size screwdriver and/or hex-head socket driver.  If you choose to do this, use Blue Loctite (which allows the screw to be removed later if necessary) after de-greasing the hole and screw threads with Bestine/Heptane (good stuff for degreasing).

Good luck!

Cheerio!
Bob Gilmore

[Dave V]

A Bachmann steamer throwing a traction tire?

Say it ain't so!   

If I had a dollar for every time...

[mmagliaro]

I really would take out the crank screw on driver 3 and the crank bolt on driver 4 (as Bob indicated), get the rods out of the way, and put a real tire on there.  It can be very tricky to get a coating of Bullfrog snot to match the thickness of the old tire, and even if it works, the grab will not be as good as with a real rubber tire.  As to why it broke in the first place, who knows.  I think I would start with a genuine tire from Bachmann.  If breaks again, then try LoveTrainHobbies for a new tire (they have a vast assortment of diameters and thicknesses).
As for removing the crank screw/bolt, a jeweler's screwdriver will work on the screw.  A little nut drive will work on the
bolt.  You probably don't have a nut driver the correct size.  But if you can measure the head with a caliper, I can point you to some really small drivers that will work.  Failing that, you can do it with mini needlenose pliers if you have them.  You just have to be super careful not to slip or crush it.

Sometimes, the rivets on the little thin link that connects to the eccentric crank (the crank on driver 3), are tight, preventing that link from loosely rocking back and forth.  Instead, because the rivets are so tight, the crank under the screw on driver 3 rotates around and around like mad to compensate, which can make it unscrew and fall out.  So make sure the rivets are not binding.

[Maletrain]

Max, Thanks for the advice.

I did look at the rods more closely with a 10x loupe, and see that the rear one is "hex-like", but not really very regular.  I have a bunch of Imperial and metric tiny nut drivers, but I would not be surprised if none match what I am seeing.  And I have little confidence that the screw threads are any Imperial or metric standard, so I am not sure I could replace the screws.  They are so tiny, they are hard to check with any sort of gauge.  And I don't have test nuts for all of the tiny screws in my kit bag.  I may try a microscope to compare some replacements visually.

At this point, I am still waiting until I get some time to run the train while I can watch it closely to see if other tires fail.  If so, then I will probably want to try some sort of means to stick the new ones to the wheel.  I have read about glue and paint as adhesives.  That seems like it would cut down on tire slip on the wheel and reduce tension along the circumference of the tire material itself. 

Or, if it sheds the other tires and still pulls the train OK, I might take Robert's advice and just run without any tires.  But, it seems unlikely that it would run OK without any tires if the reason for the tire failures is really the load from the train.

At this point, it is just one failure that might be due to a bad tire, or some previous bad handling, or too much stress from pulling the test train.  If that failure is the only one after more testing, then I will probably just replace that tire, and maybe the one on the same axle while I have it out.  But, if others fail too, then I am probably going to be back here to ask how best to stick them to the wheels.

[Maletrain]

Getting back to this, I tried to measure the broken tire, and came out with 1.0 mm wide and 0.3 mm thick, with an OD of about 9.5 mm.  The closest I could get from lovetrainhobbies.com is 1.0mm wide, 0.35 mm thick and 9.7 mm OD. 

Seems close enough, but my question here is whether it would be best to replace both tires on that axle to ensure the same OD.

Another question I have are whether it is a good idea to "glue" the tires to the drivers with some paint of actual glue.

Also, previous posts seemed to indicate that I should disconnect the rods from the last 2 drivers and leave the wheel in the frame when changing the tire, rather than just disconnect the driver with the tires from the rods and take it out by also removing the bottom plate.  Especially if I do something to stick the tire to the wheel, I am thinking I can do a better job making it round if it is out of the frame and away from the rods.  Any more guidance on that?

[mmagliaro]

If the drivers are geared, I try to leave the drivers in the frame and not take anything out of the bottom if I can help it, so
I don't have to battle with getting that geared driver back in there with the gear teeth correctly indexed.  But if
the driver is NOT geared, then I find it easier to just take the pins out of the one driver, and take the driver out to get
the tire on.

As for the LoveTrainHobbies (LTH) tires - yes, that size looks close, but also order one size smaller in diameter (8, 8.5, 8.7? something like that) at the same time. If the broken tire is 9.5mm OD, it was a good bit smaller than that when it was put onto the wheel.  A tire won't stay on if it is already about the size of the wheel when you put it on.

Look at how small a Kato Mikado tire is before you put it over a 9mm wheel.  It looks like it's about 6-7mm and it stretches out a lot to go over that wheel.  I would not expect the LTH tires to stretch as much as Kato.  They are more rigid than Kato and will break if you try to stretch them too much to get them over the rim.  But the tire needs to be at least 1mm smaller than the wheel or it won't stay put.

The LTH tires are pretty good (and I mention them often when people struggle to find tires, because they are about the only
game in town that keeps a good selection of tires always in stock).  But they are not as stretchy as OEM tires, so you
have to be a little careful getting them on.

As for matching both sides, try it first.  No two brands are ever the same thickness, but you might not notice anything
visually or running even if the two tires are slightly different in thickness.

[peteski]

Yes, like Max mentioned, you should get tires that are smaller than the driver's diameter, so they fit tightly onto the driver.  No glue is needed - the tightly fitted-tire will stay put.

The instructions (which are buried on the bottom of the page) show how to select correct diameter:

[Maletrain]

Thanks Max and Peteski!  I did miss the "subtract 2 mm" instruction at the bottom of the page. I was expecting/hoping they had taken that into account when specifying the tire size, so that it would be what it FITS, not just its nominal dimension - which is really hard to measure accurately anyway.

Regarding my gluing question:  I realize that the tires stretch and that holds them in the groove machined into the driving wheel tread.  But, I remember reading somewhere that using some sort of adhesive between the wheel and tire would make them far less likely to break and come off.  Because I am intending to use a lot of tractive force with this particular loco, I am wondering if it would be a good idea to use some sort of adhesive.  With the tire sticking to the metal, I would think that the forces on the tire are not as likely to cause it to slip, stretch and break it in tension.  Thoughts?

[peteski]

I wouldn't use adhesive.  This loco has failry small diameter drivers, so I think the tires will not slip off during use. Of course that is if the tires are rather tight on the driver.  Looser tires could slip off.  In my experience, the larger the driver's diameter is, the more prone the tire is to come off.

But I would make sure the driver's tread and the groove are thoroughly degreased before installing the tire. I use Naphtha, but other solvents (like 95% or stronger IPA or denatured alcohol) should also work well.

[robert3985]

I wouldn't use adhesive.  This loco has failry small diameter drivers, so I think the tires will not slip off during use. Of course that is if the tires are rather tight on the driver.  Looser tires could slip off.  In my experience, the larger the driver's diameter is, the more prone the tire is to come off.

But I would make sure the driver's tread and the groove are thoroughly degreased before installing the tire. I use Naphtha, but other solvents (like 95% or stronger IPA or denatured alcohol) should also work well.

Or Bestine (Heptane), which is an excellent de-greaser and won't cause rubber/neoprene products to swell or deform, or remove paint, or melt plastic...

Cheerio!
Bob Gilmore