CESM Gen2 Searchlight Signals

[dcutting]

I'm just finishing up the first run of N scale searchlights and the last packages should go out today. I've begin work on improvements for Gen2 of the product. I've linked a video showing the new base that I've created. I'm also working on adding twisted, pre-soldered magnet wire to the heads.

While this base does have an 11-pin plug, I plan to make adapter cables and boards so you can split one decoder between multiple bases. I'd appreciate any feedback on this design.

[railnerd]

So installing the signal means drilling a hole, dropping in the signal, then attaching the decoder to the connector?

Might be interesting to consider extending the distance to allow for more distance between the decoder and the signal base.

-Dave

[peteski]

So installing the signal means drilling a hole, dropping in the signal, then attaching the decoder to the connector?

Might be interesting to consider extending the distance to allow for more distance between the decoder and the signal base.

-Dave

Exactly!  overall this is excellent idea, but unless the layout structure is about 1/4" thick the area under the signal mast hole will have to be carved out for the decoder. That makes installing these much more difficult. Most layouts use much thicker base and/or foam base.

I would say extend the base to drop the connector part at least an inch or maybe more.

[ednadolski]

I would say extend the base to drop the connector part at least an inch or maybe more.

Another option perhaps would be to allow for a small-diameter (say 1/4") extension tube, which could be trimmed as much as needed.  (It might need to be installed from below, but that seems feasible.)

Ed

[dcutting]

So installing the signal means drilling a hole, dropping in the signal, then attaching the decoder to the connector?

Might be interesting to consider extending the distance to allow for more distance between the decoder and the signal base.

-Dave

Exactly. I do appreciate the idea of the longer part. I'll start exploring ways to lengthen the part without adding too much material.

[railnerd]

Exactly. I do appreciate the idea of the longer part. I'll start exploring ways to lengthen the part without adding too much material.

Or as Ed suggests, make the end caps and pick a standard tube (maybe something evergreen sells?) to glue the connector end and cap to (would theoretically not involve increasing the printing cost).

https://evergreenscalemodels.com/collections/14-polysytrene-tubes

-Dave

[Sokramiketes]

Agreed.  I like the idea but on Modutrak we have 1/4" plywood with 2" of spline/foam on top.  So we'd need about 2-1/4" total from top of plug to bottom of signal base... keeping the decoder clear of the bottom.  If you do that, I like it a lot.

[dcutting]

Or as Ed suggests, make the end caps and pick a standard tube (maybe something evergreen sells?) to glue the connector end and cap to (would theoretically not involve increasing the printing cost).

https://evergreenscalemodels.com/collections/14-polysytrene-tubes

-Dave

I didn't look at this thread until this morning, but that's the conclusion I reached after hours of pouring over the design last night. Then I'd just have two 3D printed parts.

The other change that I'm making is instead of locking a right angle male header into the board I am going to make a small PCB that has a male header for the decoder, landing pads for the magnet wires, and an extension header so that if you have multiple masts that use one decoder you can daisy chain them together with ribbon cable. The issue is that I can't seem to find a good candidate for a 1x11 2.54mm ribbon cable. It's possible that the second generation decoder may use a different plug so a simple adapter board will be needed for Gen1 boards.

David

[ednadolski]

One other thought re: the extension tube: if you can keep the 'top' end (ie, the end with the signal base) at the same 1/4" diameter, then it would require only a 1/4" hole in the roadbed which should help the fit in tight places, and also make it easier to blend into the scenery.

Ed

[C855B]

Dealing with this issue in my own layout design, I have concerns about putting something so sticky-outy on a relatively immovable foundation. Wayward hands tending to normal layout issues ranging from scenery tweaks to track cleaning to handling derailments have a tendency to find fragile bits such as signs, trees and signals. A highly-detailed signal mast with no give to it is a candidate for heads getting crushed or ladders being broken, at minimum. I have a bunch of BLMA signal bridges to spread around; these are super-delicate, needing to be given every opportunity to survive those wayward hands I mentioned.

The particular solution I'm working on is to put a connector up top as part of the signal base, using 0.050"-pitch 2X header connectors. David's approach with the barrel foundation is good, even great, and I'm going to steal the idea , but the barrel (possibly with a flange) will hold a receiving connector. With the male part of the connection on the foundation and the female connector hidden in the signal base, there should be plenty of give if the mast or bridge is nudged.

What happens underneath in terms of the decoder or other logic can still be part of the foundation. My personal preference happens to be electronics on a separate mounting plate, but whether the connection is direct or via a ribbon cable in that case is irrelevant.

[Sokramiketes]

One other thought re: the extension tube: if you can keep the 'top' end (ie, the end with the signal base) at the same 1/4" diameter, then it would require only a 1/4" hole in the roadbed which should help the fit in tight places, and also make it easier to blend into the scenery.

Ed

Unless the signal itself fits up through a 1/4" hole, don't you lose the ability to plug and unplug the signal?  You'd have to drop it in place and then solder the magnet wires underneath the layout.  At that point, you don't need the plug at all. 

I use a 5/8" drill on Modutrak.  This is to fit larger Molex connectors than what is being proposed here.

[railnerd]

Unless the signal itself fits up through a 1/4" hole, don't you lose the ability to plug and unplug the signal?  You'd have to drop it in place and then solder the magnet wires underneath the layout.  At that point, you don't need the plug at all. 

I use a 5/8" drill on Modutrak.  This is to fit larger Molex connectors than what is being proposed here.

Plugging and unplugging signals (NOT necessarily disconnecting the magnet wire) to allow for cleaning track seems like a really, really good idea.

-Dave

[dcutting]

These all sound like great recommendations. I will continue working on the design. Right now I'm busy trying to negotiate the price to produce the darth vader PCB's down to a reasonable cost. Thin PCBs are not favorites for the manufacturers.

[MK]

Maybe this?

https://www.therailwire.net/forum/index.php?topic=39154.0

[dcutting]

Maybe this?

https://www.therailwire.net/forum/index.php?topic=39154.0

That would be nice; problem is that would not be economical for 800 PCBs at a time (that's how many are on a panel). I'm getting this worked out. I'm also designing a jig/machine that will solder on the magnet wire and make a continuous spool of signal heads soldered onto wire at 6 or 12 inch intervals. I'll have more details when I get off vacation next week.

David