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Speaking of Viaducts...


VentureForth

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Tomix viaducts rise with their pillar set at around 3.5% grade.  Seems like most of my locomotives can't pull a simple 8-car Bethgon train up that grade.   My 8 car Shinkansen and 203-series work fine.  My Spectrum Dash 8-40C, which I finally got working can also pull it, but hesitates a lot - and it doesn't even have traction wheels.

 

Is 3.5% pretty rough?  What's prototypical?

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6 minutes ago, VentureForth said:

Tomix viaducts rise with their pillar set at around 3.5% grade.  Seems like most of my locomotives can't pull a simple 8-car Bethgon train up that grade.   My 8 car Shinkansen and 203-series work fine.  My Spectrum Dash 8-40C, which I finally got working can also pull it, but hesitates a lot - and it doesn't even have traction wheels.

 

Is 3.5% pretty rough?  What's prototypical?

 

Kato have an extension set for their viaduct to space out the incline over greater distance making it closer to 2%. Perhaps Tomix have something similar. You can also cut the bases of the pillars to reduce the incline further. 

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The steepest railroad grade in the US is the Saluda Grade in NC owned by Norfolk Southern. It's been in disuse for a long time but it's steepest grade was 4.9% for a short distance which meant that when train ascended it they typically had to be broke into parts because the locomotives couldn't gain the traction to pull the whole train up the hill. 

 

Prototypical would be less than 2%, preferably around 1.5%. The Tehachapi Loop in CA is 2% and will have extra motive power added on the head and rear end and about 1/3 back on the train. Horseshoe curve has a long 1.85% grade so generally they only need two at the head end to get autoracks or well cars up the grade now but there was a big stable of helpers before the latest generation of diesels. 

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14 hours ago, gavino200 said:

 

Kato have an extension set for their viaduct to space out the incline over greater distance making it closer to 2%. Perhaps Tomix have something similar. You can also cut the bases of the pillars to reduce the incline further. 

 

I'm using the old brown brick pillars that are segmented, so I can take them apart ... only I will need more snap connectors.  I'll try to spread them out and try to get closer to at least 3% or so.  Unfortunately, my current plan has the track coming under itself close to the end of the ramp, so it could be too high if I spread out the pillars...

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This one? https://www.amazon.com/TOMIX-gauge-3018-brick-piers/dp/B01KBXACGW

 

What you can do is buy another set and use a micro miter saw to cut down the bottom of the piers to make a second set of piers of intermediate heights. That way you half the incline without losing support and stability. I did this last week with some Kato viaduct piers for a tramline. It worked well and wasn't too hard. I'm going to repeat the technique to lower the incline on a curved double viaduct incline section that has been problematic.

 

The edges look rough in the photo because there's still some plastic dust on the edges but it rubbed off and left a smooth edge.

 

https://www.amazon.com/Excel-Blades-Small-Mitre-Handle/dp/B003AKSYFU/ref=sr_1_2?ie=UTF8&qid=1544542986&sr=8-2&keywords=hobby+miter+box

 

62oRccR.jpg

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Yes - those are them.

 

I'm also considering that I only need the max 55mm height over the other rails.  That would provide me with 5x 55mm pillars that I can take apart.  Since I'm looking for a 2.5mm reduction, that would give me 10 of the 20mm blocks that I can essentially "sand down" to give me those half steps.  Of course, the thought of modifying something like that I've had over 30 years is heartbreaking.  I'd have to buy the set you referred to.

 

The other problem is that the "steps" that transition between the regular and viaduct track is set at 7.5mm - between 5mm and 10mm.  I would perhaps need more viaduct pieces to complete the gradient.

 

Maybe that won't work.  If I shave off the bottom, then it won't connect to the next piece.

Edited by VentureForth
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6 hours ago, VentureForth said:

Of course, the thought of modifying something like that I've had over 30 years is heartbreaking.

 

Yes, that's never been a problem for me, but doing stuff like that isn't for everyone.

 

6 hours ago, VentureForth said:

 

The other problem is that the "steps" that transition between the regular and viaduct track is set at 7.5mm - between 5mm and 10mm.  I would perhaps need more viaduct pieces to complete the gradient.

 

 

You can carve a 3mm step out of styrene, wood, or foam. to prop up the regular track at one track interval before the transition piece. Or you could use one of the pieces that you cut from another pillar and fill in the center part, if you want this step to match the rest. 

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So one of the regulars pointed me to the 70mm overhead kit that you can screw a piece of track to. I can't find any single track "blanks" for C280-15 and S140 tracks.

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There is no blanks for curves or 140mm lengths.

 

You can however buy regular viaduct pieces and switch out the tracks for other tracks. Eg wooden ties to concrete ties.

 

There are however bridge spans for double track c280/317-15 and s140.

Edited by katoftw
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So I spaced out the pylons and doubled the distance between them, effectively reducing the grade to 1.5%. 

 

Didn't help. None of the other locos could pull eight light cars.

 

Back to 3%...

 

Bullfrog snot? Expensive...

IMG_20181217_203051.jpg

Edited by VentureForth
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2 minutes ago, gavino200 said:

Those track segments are quite short. AFAIK the gradients are calculated using a long track piece between each pier. 

Nope. Even per the documentation, it's 5mm rise for every 140mm length.

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6 minutes ago, VentureForth said:

Nope. Even per the documentation, it's 5mm rise for every 140mm length.

 

They be trippin'. That'll never work. You need longer track segments. Also you can try taking out the curves, though they do seem to be a main feature of your layout. 

 

It sort of pisses me off that companies sell these sets without disclosing that most of their locos can't handle them. 

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Kato is 10mm rise per 248mm piece. They do 5mm rise for first and last transition ramp. For 4% rise.

 

The basic ramp pylons is 5 15 25 35 45 and 50mm.

 

So I see no issue with 5mm per 140 or 10mm per 280.

Edited by katoftw
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4 minutes ago, katoftw said:

So I see no issue with 5mm per 140 or 10mm per 280.

 

Yes, except that it doesn't work. Many Kato locos also have trouble with the Kato recommended intervals.

 

What's you say is right in theory. Unfortunately, the theory seems to be....eh....let's say.......imperfect.

Edited by gavino200
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6 minutes ago, katoftw said:

Oh yeah if you max out the 4%. Only 4 car trains tend to climb.


Ah yes. I'm pretty sure there's no disclosure about that. 

 

But even at that, I think you're giving them too much credit. At 4% a lot of locos can't even handle a 4 car load. At 2% quite a few locos have trouble with even a meager load. 

 

Some locos - powerful heavy locos with traction tires can pull a good load up even a 2% incline. It's just not hard to find a loco that doesn't handle well. Quite a disappointment when you buy a loco that can't handle your manufacturer specified track incline. 

Edited by gavino200
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8 minutes ago, katoftw said:

And curves dont help either.

 

 

Yeah, curves really confound the problem. It took me a long time to work that out!

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Interestingly, even when I doubled the pitch of the pylons (1.8% grade), the strain was in the straightaway.  Go figure.

 

The advantage of 5mm per 140mm segment is that I can have a pylon at every joint.  I don't think that I'd want to stray from that.  An unsupported joint isn't a great idea.

 

I've put together the above layout for the inside loop only (minus the station sidings and the turn table spur).  I've just taken it down.  I may putz around with it a bit and see what I can come up with.  But even so, I'm limited to a 4'x8' layout, so getting a long ramp up to fit is the challenge.

 

That being said, curves are awesome.  😄

Edited by VentureForth
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VentureForth

OK.  The viaduct is really bothering me now.  I suspect that I may have fouled my tracks and wheels with oil when I was lubricating all the gears.  I KNOW my 8-car Shinkansen could make the grade, but it doesn't now.  Even a 6-car 201 is having trouble.  I need to find my track cleaning car (MIA) and the wheel cleaning track.  I don't want to buy another set - they're pretty pricey.  But if I have to...

 

Can't even find the full 6551 or 6552 sets any more.  😞

Edited by VentureForth
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1 hour ago, VentureForth said:

OK.  The viaduct is really bothering me now.  I suspect that I may have fouled my tracks and wheels with oil when I was lubricating all the gears.  I KNOW my 8-car Shinkansen could make the grade, but it doesn't now.  Even a 6-car 201 is having trouble.  I need to find my track cleaning car (MIA) and the wheel cleaning track.  I don't want to buy another set - they're pretty pricey.  But if I have to...

 

Can't even find the full 6551 or 6552 sets any more.  😞

 

If your tracks are greasy, you may want to consider rubbing them down with a cloth and some alcohol.

 

There are some ideas in this thread.

 

 

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Yeah your old index finger, a soft cotton rag and some isopropanol (and maybe a litttle ethanol for you if you choose), works wonder to remove grease from track when it’s bad. Keep wiping until the dark lines don’t show up on the rag!

 

ive always mean to set up a test loop to run trains on for a while after lubing to blow out the excess right away, then clean the wheels on paper towel with isopropanol, but usually don’t do it....

 

jeff

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VentureForth

 

After cleaning the track and incorporating my new power pack, switches and track. Not edited.  Note: after 35 years, swapped out the brown track in the viaduct pieces with FT.  Yeah, I didn't have enough brown tie pieces. Lol. 

 

There is still a bit of hesitation, but the trains make it up the grade now.

Edited by VentureForth
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