turnouts on ho track power both sides

[Len]

Even with the scenario you suggested, wyes still need to be isolated. Draw a wye, with both rails, on a piece of paper. Start on one of the "mainline" rails and follow it up one leg of the wye to the common section. Now follow that same rail down the other leg to the "mainline". You'll find your on the opposite rail of the "mainline" from where you started, essentially connecting the two mainline rails together electrically. That's called a short, which is not a good thing, and has nothing to do with reversing the direction of the loco.

Len

[jbrock27]

Okay, but that never happened in the way that I employed it.  Perhaps I did not adequately describe how I did??

And just in case it makes a difference, this is an Atlas WYE I have been talking about.  I will add this as well; I basically used it in place of using a turnout; it just fit better for what I was doing, than a turnout.

[Len]

Sorry, I thought you were talking about a full blown wye using three turnouts or wyes.

If you're just using the #4 Wye as a turnout, then no, gaps aren't needed unless it's a situation you'd gap with a standard turnout.

Len

[jbrock27]

Sorry, I thought you were talking about a full blown wye using three turnouts or wyes.

Nope.  That is why I took great pains to describe how I was using the WYE and mention specifically that I was not using the WYE in the traditional sense.  I am glad you got back to me and confirmed this-there is no good reason to not double check on something you think is proper against what others know .

Now if I could get some suggestions on my bridge pier issue, that would be great .

[Len]

Are you using the piers for an over-n-under arrangement, or to create a level "trestle" across a valley? It makes a slight difference in the solution.

Len

[jbrock27]

Yes on the over/under, but not in a figure 8.  I have 2 AHM trestles I have put together that form the "bridge" and to either side of the bridge, the piers go progessively down until they reach table level.  I have curves (mostly 18"R, a couple of 22"R) in this.  The track then finds it's way back under the bridge.
Thank you Len for your help.

[Doneldon]

I have 2 AHM trestles I have put together that form the "bridge" and to either side of the bridge, the piers go progessively down until they reach table level.  I have curves (mostly 18"R, a couple of 22"R) in this.

jim-

The appearance of those crossties floating free in the ether has always bothered me, too.

                                                                                                                          -- D

[jbrock27]

I know Doc.  I got the term I used to describe them, from something you wrote at one time.   Should have given what that look would be, more thought, but did not unfortunately...

[jward]

jb,

you can get some plastruct I beam sections and glue them under your track, trimmed to fit the space between the piers.

[jbrock27]

I think I remember you mentioning that sometime before as well Jeff.  Thank you.  I will look for those.   

[Len]

Great minds think alike. You can take what jward said a bit further using sheet styrene to make a deck between the piers. It's simpler to do than to describe, but the steps are pretty straight forward. Just remember support decks are straight, even when holding up curved track.

1. Place the longest car/loco you've got on your 18" curves and measure the overhang of the car. This would be at the middle of the car on the inside of the curve, and the ends on the outside of the curves. Do the same for your 22" curves. If you plan to get something bigger later on, track down the measurements and make a mock-up to check overhang for clearances. Write down the numbers for future reference.

2. Deck Width: Add up 18" curve inner overhang, 18" curve outter overhang, 1-1/4" tie length, plus 1/4" for safety to get the total deck width. For consistency, use the same width for your 22" curves. Only the overall length will change between 18" and 22" curve spans.

3. Deck Length: Measure the straight line distance from the center of one end of an 18" curve to the center of the opposite end. Do the same for a 22" curve. Take one pier and measure the width of the little clip that holds the track in place on top. Subtract this number from the end-to-end track measurements you just did. This is your deck length, measured from width center at one end to width center at the opposite end.

4. Lay out, making sure to mark the center-line, and rectangles of sheet styrene to the width and length measurements you figured out above for the 18" and 22" curves. Make the length a bit longer than you want to end up with, because the ends will be angled when done.

The next step is easier if you have one of these gizmos:


5. Using a protractor and straight edge, mark lines that pass through the end center points at a 15deg angle (half of the 30deg arc of the curve) for 18" curve decks. So you end up with something looking like roughtly like this:
  -----------------------
__\ ____________/___ Center Line
    \ ___________/
For 22" curves the angles on the ends should be 11.25deg, to match the 22.5deg arc of those curves.

6. Cut your decks out of the styrene sheets, then put track and deck in place on the piers to test fit everything. Adjust length as needed.

7. Once the deck is okay, you can remove to add the Plastruct, or whoever's, girders underneath, and whatever girders or guardrails you like on top, and paint to suit. Once dry, install and you're good to go.

Len

[jbrock27]

Excellent!  Thank you as well Len.  If I have any questions about this, I will get back to you.

**I have checked and do not have that gizmo (above).

[Len]

You can get the protractor 'gizmo' at just about any hardware or home improvement store. They're less than $10.00, and the metal edge is handy for scribing plastic with an X-Acto blade.

But like I said, it makes things simpler to have one, but it's not essential. You can use a regular plastic protractor and ruler to lay out the basic deck size and shape on poster board. Then cut out the poster board to use it as a template for laying out the decks on styrene sheet.

The key points to remember are the 18" curve deck ends are 15deg angles, the 22" curve deck ends are 11.25deg, and the 22" curve decks are longer than the 18" decks.

Len
 

[jbrock27]

I definitely like the suggestion of a metal protractor, another good suggestion.  I use a metal ruler now for trimming styrenne.  I picked it up at Walfart.

Interesting that the 22" decking will be longer than the 18", as the 18" track is about 3/4" longer than the 22".  I will also note that I have already soldered several sections of the curves together, a combo of 18 and 22, for 2 reasons:  1) I don't have to worry about continuity 2) It was done to make it much easier to slide the piers up and down the track w/o worrying about the track separating at the track joints.  On the other hand, I don't know how having done that, it will or will not make this part of the project more difficult

[Len]

The mixed curves shouldn't matter, just use the right deck piece between piers under each curve section. That's where making poster board templates for trial fitting can come in handy.

And your right, individually the 18" curves are a bit longer than the 22". I was tired, and thinking about the size of a 90deg turn using 18" curves vs using 22" curves when I wrote that.

Len