Tehachapi Loop II

[pdx1955]

No issue with Peco insulated joiners - never had one close up on me and I have over a hundred in use now. You could also apply CA to the rail before you cut it because if its glued to the ties it won't move. The super flexibility eventfully drove me away from Atlas as some places always want to kink. Once you curve Peco it stays there.

[GaryHinshaw]

Ed - A few random questions and ideas:

* Do trains run through this patch ok?  I'll be the first to admit that it looks a bit clunky, but it does seem to me that it might at least work.

* When I lay my ME track with "joinerless" joints on a curve, I pre-bend the ends of the rail to roughly match the curve radius.  It doesn't have to be precise, it just helps alleviate some stress.  In fact, all of my lower deck mainline is just resting in place with no joiners and only 1-2 pair of temporary nails per stick, until I get around to gluing it.  Could you do something similar here, rather than cutting gaps after the fact?

* Do you need to have your gaps on a curve?  Could you elongate the staging slightly to make it an oval (like the Vortex)?  I'm sure this would not be trivial at this stage, but it would allow you to place gaps in straight sections.

* Don't hesitate to "vote your conscience" and start over with different track, or whatever else it takes to meet your goals.  You definitely don't want reliability issues in there!

-gfh

[ednadolski]

No issue with Peco insulated joiners - never had one close up on me and I have over a hundred in use now.

That's some encouraging info, thanks!   I will try to get my hands on some Peco asap to try out.  Doesn't Atlas have to be shimmed up to join it with the Peco?  (I believe the bottom of the Peco rail also needs to be filed flat in that case).

* Do trains run through this patch ok?  I'll be the first to admit that it looks a bit clunky, but it does seem to me that it might at least work.

A test truck seems OK, but I'm concerned that some of my larger-flange locos could bottom out on the gauge-side nail heads.

Looking closely one can also see places where the inner rail is no longer parallel to the outer rail.  This seems like a potential problem area for long trains where there is enough tension for some wheels to start rolling against the inner rail of the curve (tho not necessarily enough force to actually lift the outer wheels or cause a stringline).  It looks more egregious when sighting along the length of the track, but also is evident looking top-down.

* When I lay my ME track with "joinerless" joints on a curve, I pre-bend the ends of the rail to roughly match the curve radius.  It doesn't have to be precise, it just helps alleviate some stress.  In fact, all of my lower deck mainline is just resting in place with no joiners and only 1-2 pair of temporary nails per stick, until I get around to gluing it.  Could you do something similar here, rather than cutting gaps after the fact?

Not with Atlas track, it won't stay in place at all without either nails or glue.  It should in principle be possible to remove the loose rail from the Atlas tie web and pre-bend it in the FastTracks roller tool.   I did that when hand-building the curved turnouts. Unfortunately tho the roller tool cannot bend the last few inches of a rail, which is where it is needed the most in this case.

* Do you need to have your gaps on a curve?  Could you elongate the staging slightly to make it an oval (like the Vortex)?  I'm sure this would not be trivial at this stage, but it would allow you to place gaps in straight sections.

Hmmm that would essentially mean starting over on the entire helix (and I am not sure an oval would fit the space).  The detection blocks are approx. 1/4 turn in length so even an oval could not eliminate gaps on curves.

* Don't hesitate to "vote your conscience" and start over with different track, or whatever else it takes to meet your goals.  You definitely don't want reliability issues in there!

Amen on that!  The track right now is glued in place with an adhesive caulk, which is nice and solid but will be a bear to remove and scrape clean for replacement track.  But the more I look at that loose/wobbly Atlas rail, the more it bugs me... I guess I am still searching for a justification to keep it (other than the obvious work+cost).   

Ed

[Ed Kapuscinski]

Why not just throw some insulated joiners in the gaps?

[pdx1955]

That's some encouraging info, thanks!   I will try to get my hands on some Peco asap to try out.  Doesn't Atlas have to be shimmed up to join it with the Peco?  (I believe the bottom of the Peco rail also needs to be filed flat in that case).

If Atlas code 55 has the same tie thickness as ME C55 then yes, the Atlas will need shimming. The easier way is to put a railjoiner on the Peco, crimp it flat, and solder the Atlas to the top. It should come out pretty close with maybe some light filing. No need to file the bottom flange off the Peco this way either.

[pdx1955]

Why not just throw some insulated joiners in the gaps?

The issue is that once the rail is cut it wants to be straight which ends up as a kink. insulated joiners generally can't fix that as they are too pliable. He'd have to glue the rail down first before doing that, or like I suggested before, filling the gap with a glued-in piece of scrap plastic.

[Lemosteam]

Could you, while the track is in a curved state, using a thin soldering tip melt the atlas ties out from under the place where you want to gap, slide in one of those solderable tie plates after drilling a track nail hole or two under the rails or try gluing or it to the roadbed, solder the rails to the plate and then cut the gap?  I would think that would stabilize the rail to keep it in place after you gap it.

[ednadolski]

The issue is that once the rail is cut it wants to be straight which ends up as a kink. insulated joiners generally can't fix that as they are too pliable.

Are the Peco insulated joiners any more/less pliable than the Atlas ones?   Seems at least it should be less of a problem with the Peco, since that doesn't have the loose/wobbly rail and thus should be less prone to kinking.

Could you, while the track is in a curved state, using a thin soldering tip melt the atlas ties out from under the place where you want to gap, slide in one of those solderable tie plates after drilling a track nail hole or two under the rails or try gluing or it to the roadbed, solder the rails to the plate and then cut the gap?

What I would do now is plan the location of the gaps ahead of time and trim away the plastic ties before gluing down the track, then install the PCBs.  The PCBs probably don't even need to be glued to the plywood, since their real job is just to keep the gapped rail parallel to and in gauge with the outer rail.


Ed

[pdx1955]

Are the Peco insulated joiners any more/less pliable than the Atlas ones?   Seems at least it should be less of a problem with the Peco, since that doesn't have the loose/wobbly rail and thus should be less prone to kinking.

The Peco ones seem to hold the rail better as you mentioned as they are not fighting the flexible rail.  Again, I've never had an issue with a Peco insulated joiner.

[wazzou]

I think the simplest solution for track already laid is to fit an insulating piece of Styrene into the gap, filling the space lost from the kerf of cutting the gap.  Wouldn't that then correctly realign the rail in gauge?

[Lemosteam]

[quote author=ednadolski link=topic=37285.msg523488#msg523488 date=1493347263

What I would do now is plan the location of the gaps ahead of time and trim away the plastic ties before gluing down the track, then install the PCBs.  The PCBs probably don't even need to be glued to the plywood, since their real job is just to keep the gapped rail parallel to and in gauge with the outer rail.


Ed
[/quote]

I was referring to track already laid and I understand the location planning bit.  If you solder the PCB to the flex first, the rails will not follow curvature, unless you are saying you are going to lay the track with the gap in the ties and then slide the PCB in and solder after.  The PCB also provides insurance against expansion closing the gap.

I don;t think a soft piece of styrene in such a small sufrface area of contact as the very end of a cut rail will be enough to force the bend back into the rail unless one bends the rail to the curve and then inserts the styrene, but I don't think using the styrene to force that bend would work.

[ednadolski]

If you solder the PCB to the flex first, the rails will not follow curvature, unless you are saying you are going to lay the track with the gap in the ties and then slide the PCB in and solder after.

YEs, the latter.  With individual PCB ties, one could also pre-solder the ties to the outer rail, and then solder to the inner rail after the track goes down but before making the gap cut.

Ed

[Lemosteam]

YEs, the latter.  With individual PCB ties, one could also pre-solder the ties to the outer rail, and then solder to the inner rail after the track goes down but before making the gap cut.

Ed

To me the robustness is in the multi-tie PCB's integrity,  If you use individual ties they could move independently of one another from expansion.

[ednadolski]

I don;t think a soft piece of styrene in such a small sufrface area of contact as the very end of a cut rail will be enough to force the bend back into the rail unless one bends the rail to the curve and then inserts the styrene, but I don't think using the styrene to force that bend would work.

Right, once the cut is made, it is very hard to get the rail precisely aligned to the previous curvature.  The styrene only gives one anchoring point, but to make a curve you need at least three points.

Ed

[ednadolski]

If you use individual ties they could move independently of one another from expansion.

Not sure I see how.  Once soldered to both rails it should form a rigid structure, unless the joints fail.   (Just like soldering throwbars to non-hinged points).

Ed