Figure 8 layout

[DougInCal]

I recently purchased an N scale set with 24 inch circle.  It currently fits on the 24"x48" table next to my computer desk.

I would like to create a figure 8 using a 90 degree cross-over.

Just "eyeballing" the circle it looks like I can remove 3 of the 11 pieces of 11.25" curved track and put in some straight track and the cross-over.  Then create another 8 piece circle and straight track to finish the figure 8.

I don't know how to calculate the straight track, but have considered buying 5" straight track and various sizes of straight track.

1) Does this seem reasonable?
2) Would the overall "length" (outside track) exceed 48 inches?

(Instead of the cross-over, I have seen 16-piece graduated trestles on different sites, but Bachmann doesn't seem to have it on their site.  Questions #1 and #2 apply to this scenario, as well.)

TIA. 

[Joe Satnik]

Doug,

I'm certain that you will need a table longer than 48".

Formulas are near the bottom of this thread page:

http://www.bachmanntrains.com/home-usa/board/index.php/topic,28172.15.html

Hope this helps.

Sincerely,

Joe Satnik

 

[James in FL]

HI DougInCal,

Time for some trig, get your calculator.

Building a figure 8 using a 90 degree crossing the formula looks like this;
Strleg = r - (xlength/2)
Where Strleg = Straight leg from the crossing (you will need 4),
and xlength = Crossing length across opposite faces.
The 90 degree crossing measures 1.125.

Overall length of the layout (track centers) is;
The radius of the loop
PLUS
The radius of the loop times the sine of half of the crossing angle times the tangent of half the crossing angle
PLUS
The radius of the loop times the cosine of half of the crossing angle.

Double that sum to get the full length and add an extra inch for the roadbed.

This is from the thread Joe mentions above.

Post your maths and your results, several of us here actually like this kind of stuff.

@Joe
I don't know how to write the proper equation that expresses that formula for overall length.
Can you help here?
I'm thinking;
r + [r(sin xdeg/2)(tan xdeg/2)] + r(cos xdeg/2)

and/or
r + [r(sec xdeg/2)]

Maybe
r+ r(sec xdeg/2)



Is this proper?
Please correct me if not.

Thanks

[ACY]

The only way you will fit either version of a figure 8 in the space provided is with flex track with really sharp curves that would restrict you to running only 40' rolling stock and only 4 axle diesels or 0-4-0's or a porter or something like that. If you can increase your space to 3' x 5' it should fit comfortably without anything too close to the edge.

[Ken G Price]

I have to agree with the others, that you need a larger space. Doing any thing in model railroading that is half way done will com back to bite you. Or frustrate you so much that you quite.

Those here have made many mistakes, so you do not have to do them.

[Joe Satnik]

Hi, James.

Nice to hear from you again.

I would put any (complicated) equation into Microsoft Excel spreadsheet format.

Use the same function abbreviations, and be careful of parenthesis placement.

Hope this helps.

Joe 

[kmcsjr]

Theory aside. I designed a few options in rrtrack 5

1) to use 90 deg you need 24x57ish
2) if you use a 30 deg x it will fit using 8 sections of 0.875" straights.

[DougInCal]

I ordered the 30 degree crossover, and a pack of various connectors.  To get 8 of the .875 I would have had to order several packs.  So...I'll see if I can cobble together these and maybe it will work.

Thanks for the help.

[James in FL]

Yes, unfortunately they (.875) only come two in a pack, four packs is going to be big $$$.
That's as close as you're going to get with EZ track unless you cut it.
I calculate that to be only .028 over per leg.
EZ track will forgive more than that into each of the 11 curve sections.

[kmcsjr]

I ordered the 30 degree crossover, and a pack of various connectors.  To get 8 of the .875 I would have had to order several packs.  So...I'll see if I can cobble together these and maybe it will work.

Thanks for the help.

I played with the smaller pieces. Multiple combinations will come close. The track should be forgiving enough. The closest was 1.875 on one approach a 0.75 and 0.875 on the other approach.

As much as I'm a cult follower of Bachmann Steamers, I also am a cult follower of another ballasted track brand. This 30 deg crossover has me thinking about some small space ideas. Please post how it works out.

[DougInCal]

Well, my track is "in the mail", so now all I have to do is wait.

I was wondering if EZ-Track is compatible with "another ballasted track brand?"

I can see how this hobby can become addicting.  I am already thinking about moving my bookshelves out of my office/computer room and using that space, and the space of the existing 4' x 2' table, to create a layout table. 

I am thinking of running a shallow grade along the wall (single track) out of the layout table, and then using a loop over my terminal (still an old CRT) to return to the main table.  Is a gap in the track of the loop all that is required to handle the polarity when leaving the loop, or is wiring required?

Ken P, I browsed your photos and was impressed with all that work!  Do you have any "overview" images of the whole layout?

[kmcsjr]

The short answer on compatabilty is no, but.... With some creativity you can make a conversion piece, by modifying track ends. What you envision around the crt is called a reverse loop. And it will need some wiring. Best you google n scale reverse loop for wiring info. While it isnt complicated, it is very well described. I run a bunch of loops in small spaces. There will be a space issue if you want to stick to the fig 8 and add this track as the turnouts aren't tight enough to fit without making the loop to big for the table. Kato and Tomix make tighter turnouts, but the software I use doesnt include them. For simply running though you could easily make something that stretched 1/2 of the figure 8 to be the loop around the crt. You could also skip the figure 8 an have 2 concentric loops, so you would end up with 4 tracks on the shelf. The outer loop could be bachmann, which is fine. The inner loop Kato or Tomix, as they make smaller radii.

Addicting no... well a bit... umm a lot

As to the shallow grade, try to keep it at 2 percent or less. There are myriad reasons, but simply put, the higher the grade, the shorter the train and some locos are better on grades than others

[kmcsjr]

Also bmann does make a graduated trestle pn 42523, but I am not sure it would fit on the 30 deg figure.

Also, which loco do you have, so we can check the incline performance

[DougInCal]

The engine is a Santa Fe diesel, "F7-A Diesel Locomotive with All-Wheel Drive ...", from the box.  (also, two cars and a caboose.)

[DougInCal]

I was looking at the U.P.® #1838 - Prairie 2-6-2 & Tender, with E-Z-Mate® Mark II coupler on tender.  Some threads discuss different couplers, and I was wondering if my rolling stock from the kit (previous post) would work with this engine/tender.  The box doesn't include information about the couplers.

The couplers look like a thumb and fingers curled into a loose "C."  They don't connect when pushed together, but must be connected by lifting one and dropping it in vertically.