Scratch building tunnel

[Hogjaw]

THANKS FOR ALL YOUR INFORMATION!

 

Looks like my 4' x 8' table must be expanded prior to adding track above the tunnel.

Again Thanks all.

[Anonymous]

Thanks John!  I tend to swap volts and watts (I know enough about electricity to be dangerous).

That is about what I thought on the grade.  I was going to go home and use the old string method to determine the length...

Bob (lionelsoni) posts a lot of good information here, and I keep forgetting to copy his posts when he posts something I want to keep!

[johnandjulie13]

Hello Lionroar88:

I assume you mean volts and not watts.  Lionelsoni provided the formula for measuring the length of an arc in a previous post.  Since I am not that mathematically gifted I would be estimating.  First, I am assuming that the O48 curved sections are 30 degrees (12 sections to make a circle).  That would mean each section is about 12.5" in length.  So you have a total of about 92.5 inches of track (5 curved and three straight sections).  Since you are rising by 6", the grade is about 6.5%.

Regards,

John O

[Anonymous]

Keep in mind there are other factors as well:

Number of pulling and pushing engines.
Number of cars
Weight of cars

A single engine may be able to make 10%+ grade on its own, but if you put one car behind it then the engine may not be able to make the grade.

A single engine may be able to make a 6% grade with 4 light weight cars (flat or gondola), but only 1 heavier car (full scale boxcar, or loaded hopper).

Two engines in latch-up could pull a long consist of light weight cars, but may require a single 'pusher' engine to help with the same number of heavier cars on a steaper grade.

BTW - Latchups and pusher engines are only recommended on TMCC routes.  I have tried doing this using conventional mode engines with varying degrees of commedic results.  I also do not know if DCS supports latchups and pusher engines.

Latchups and pushers are common sites on modern railroads moving through mountainous terrain.

Also, I have a B&O Mikado (no trailing cars) that I have running on a test layout, I've been able to go from 0" to 6" using the following track configuration (haven't figured out the length): O-48 crv, O-48 crv, O-48 crv, 10" str, O-48 crv, O-48 crv, O-48 crv, 10" str, 10" str.  At 14 watts the engine stalls at the first 10" str, at 16 watts the engine stalls about 1/3 through the second curve, at 18 watts it makes the entire rise.  Going down the same configuration the engine picks up a bit of speed but does not derail.  I am planning on reducing the grade by adding 4 additional straights.  I'm hoping to get the Mikado to pull 7 passenger cars up the grade.  I'm thinking for the downgrade I may add 8 additional straights.

[johnandjulie13]

Hello Hogjaw:

Reggie has the right answer, for a 3% grade.  The formula is pretty easy:

Length of track = height needed / grade

So, if you want to go from zero to six inches with a 3% grade it would be

6/.03 = 200 inches.

If you wanted to use a 2% grade, then:

6/.02 = 300 inches.  You can see that a one percent drop in grade, increases the length needed by 50%!.  You will need to determine the appropriate grade based on the space that you have available.  There is another recent thread on this board that discussed using a grade sloped as much as 6%.

Also, the slope up, does not have to be the same as the slope down.  Just be careful on those steep declines...a train can pick up a lot of speed going downhill!

I hope this helps.

Regards,

John O

[thatboy37]

i can try to help. i just did the same thing with the rise and run i got a ton of help from the guys on this forum. what i was told about 200 inches would be sufficiant but i took it a little farther and went from 0" to 7" in 233 inches add maybe a couple more inches. to get further examples you can look at my post titled "another question on grades" and one titled "? on rise and run". hope this helps as it did me. if it doesn't you will get more help from the guys here later once they get a chance to look at your post

[Hogjaw]

Using Lionel O fast track.

Building tunnel from scratch and also adding fast track on top of tunnel for extra run. 

What is recommended track length for grade to get me from 0" to 6" (top of tunnel) to avoid engine overload or premature wear?

Will track length (grade) need to be same to get back down (6" to 0" grade)?

New to hobby, but so far rearranging track, buildings, scenery, has been nearly as much fun as turning switches and running the Copper Iron train!

Thanks.