Tehachapi, BC

[robert3985]

Gary,

Instead of a brass tube, with thick walls, you might want to consider stainless hypodermic tubing, which has much thinner walls, but more strength than brass.  That's what I'm doing for my scratch-built Darth Vader Type-D 1st gen signals on my 1950's UP mainline. 

After trekking out onto the mainline and measuring the diameter of the prototype D-type signal masts, I bought my tubing from Small Parts back when they hadn't been gobbled up by Amazon.  Luckily, after checking my Amazon Prime account I see that "hypodermic tubing" is still available in certain diameters and wall thicknesses.

Just for your information, I assume the brass mast on your signals is 1/16" (.0625") OD, with a 1/32" (.03125") ID.  A close equivalent 17 ga. SS hypodermic tube has an OD of .057", and an ID of .050" with a .004" wall thickness.  This gives you a slightly smaller, more prototypical mast diameter, and an ID that's .01875" larger than your present brass tubing mast...which is significant.

If you want a bit more strength, and a slightly larger than 1/16" OD tube, then the next size up is 16 ga. SS hypodermic tubing (.065" OD) with a .0535" ID, and a .006" wall thickness.

Lastly, if you want an even larger ID, then a 16 ga. tube (.065" OD) with a .0555" ID, and a .00475" wall thickness is available.

Here's the link at Amazon Prime: https://www.amazon.com/Stainless-Hypodermic-Tubing-0-0625-0-00475/dp/B003TFFCBA/ref=sr_1_1?ie=UTF8&qid=1532141134&sr=8-1&keywords=hypodermic+tubing+.0625%22+OD

Cheerio!
Bob Gilmore

[C855B]

A good source here, as well: https://www.ngineering.com/tubing.htm . I keep forgetting I have a supply of several sizes of these in the signals project stash.

[GaryHinshaw]

Thanks for the input, guys.  I don't know what brand of tubing Showcase uses, but I measured it to be .032" OD and ~.021" ID, so quite close to the 0.8 mm x 0.6 mm tubing @Wutter references.  I don't expect to have any trouble with my 2-head signals, but 3 will likely be a challenge.  Fortunately, I have only one such mast in my signal plan (at Kern Jcn) so I'll cope somehow.

Note that the Showcase kits have the relay boxes cast directly around the tube, so it is not practical to swap in a different tubing.  This lets them cast interior detail more easily; good for those that wish to have an open door here and there:



I also confirm that the new shipment of RR-CirKits LEDs shipped with unbraided magnet wire leads, as the above two examples demonstrate.

[Smike]

Hey Gary, I just assembled a two head Showcase Signal with the stock tubing and no issues with threading the leads. I did however thread the top light straight down into the top of the brass tube (basically mounting the light at the very top) I was nervous the trying to thread the second wire lead through a opening on the side plus the friction from the other set. Direct thread for the 3rd head to be able to easily thread it.

I agree, these are great kits. [ Guests cannot view attachments ]

[GaryHinshaw]

Very nice smike!  Nice to see another shoutout for the Showcase kits.  I hope these signals remain in production, as N scale signals have a tendency to come at go at inopportune moments.  These models are real keepers.  I'm hoping to get back to my build soon, but I have a bunch of body-mount projects in the queue at the moment, so all good things in all good time.

-gfh

P.S.:

Direct thread for the 3rd head to be able to easily thread it.

Pardon my puzzlement, but what does this mean? 

[peteski]

Thanks for the input, guys.  I don't know what brand of tubing Showcase uses, but I measured it to be .032" OD and ~.021" ID, so quite close to the 0.8 mm x 0.6 mm tubing @Wutter references.  I don't expect to have any trouble with my 2-head signals, but 3 will likely be a challenge.  Fortunately, I have only one such mast in my signal plan (at Kern Jcn) so I'll cope somehow.

If you could utilize the mast as a common electrical connection for the LEDs, that would reduce wire count by one for each head.  So on a 3-head signal you would only need to thread 9 wires through the mast. Alternately, while it would require some precision soldering, you could swap the preinstalled magnet wires for ones that are lighter gauge.

[Smike]

P.S.:
Pardon my puzzlement, but what does this mean? 

No worries a little convoluted If I was doing a 3 head signal I would thread the magnetic wire for the lower two heads from opening cut on the side of the tube, while the top head I would thread directly down into the top of the tube.

[GaryHinshaw]

Roger that.  Fortunately, my 3-head signal is a ways off: I first need to fabricate the hand-laid turnouts at Kern before I worry about that signal (I'm still using temporary Atlas turnouts at Kern).  Using the mast as a common seems like a viable fallback if threading is difficult.

[DKS]

A little silicone gel lubricant might help as well.

[Philip H]

A little silicone gel lubricant might help as well.

 

TWSS

 

 

[C855B]

A little silicone gel lubricant might help as well.

Good idea. 1:1 electricians use a gelled lubricant for pulling wires through conduits. It makes the job so much easier.

It's not silicone-based, I think. <tmi>It's more like a thick K-Y and is water soluble, and wipes off easily. Can't say the same for the silicone stuff.</tmi>

[DKS]

It's not silicone-based, I think. <tmi>It's more like a thick K-Y and is water soluble, and wipes off easily. Can't say the same for the silicone stuff.</tmi>

You're right, it's polymer-based.

Probably the biggest problem will be getting a small amount, when the stuff is sold in big bottles. Maybe if you know an electrician, he'd let you have a teaspoon of the stuff--that'll be a lifetime supply for modeling needs.

[Jbub]

TWSS

 

 

Twice in one day!

Thank you Michael Scott

[C855B]

You're right, it's polymer-based.

Probably the biggest problem will be getting a small amount, when the stuff is sold in big bottles. Maybe if you know an electrician, he'd let you have a teaspoon of the stuff--that'll be a lifetime supply for modeling needs.

Quart bottles are the standard size, and it's cheap at the DIY stores - the yellow stuff is $6.50/qt., although a 5-gallon pail of it will set you back fifty bucks or so.

I keep it on hand for my own 1:1 projects. I think it's too thick for MRR purposes. Joking aside, I was semi-serious about the K-Y reference, alluding to your silicone lube idea. The silicone-based "personal lubricants" would be about just right in terms of consistency for pulling fine wires through tubing. I'd test it first, though, in case it acts as a solvent and strips off the insulation. Doubtful, tho'.

[DKS]

Quart bottles are the standard size, and it's cheap at the DIY stores - the yellow stuff is $6.50/qt., although a 5-gallon pail of it will set you back fifty bucks or so.

I keep it on hand for my own 1:1 projects. I think it's too thick for MRR purposes. Joking aside, I was semi-serious about the K-Y reference, alluding to your silicone lube idea. The silicone-based "personal lubricants" would be about just right in terms of consistency for pulling fine wires through tubing. I'd test it first, though, in case it acts as a solvent and strips off the insulation. Doubtful, tho'.

Well, I wasn't referring to "personal" lubricants; I was recommending the cable-pull stuff (I have a quart of it sitting around somewhere myself). Forgot that it wasn't silicone. Serves me right it went off on a tangent...

As for it being too thick, it is water-soluble, so...