3D printed Sn2 turnout fixture

[Sumner]

Nice work!!

Not sure if this interests you are not but I've used the bottoms of the PCB ties to run the power to the rails past the frog.  Solder a very small wire to the top of the powered rail and wrap it to the bottom and solder it there.  Then do the same over at the rail you want to power.

I do that at times and other times do it like what you showed with the smallest wire I have.

Sumner

[JeffB]

Nice work!!

Not sure if this interests you are not but I've used the bottoms of the PCB ties to run the power to the rails past the frog.  Solder a very small wire to the top of the powered rail and wrap it to the bottom and solder it there.  Then do the same over at the rail you want to power.

I do that at times and other times do it like what you showed with the smallest wire I have.

Sumner

Thanks...  I thought about something similar.  I was just going to drill a hole down through the PC at each rail, then solder a brass "spike" to the top and bottom of the PC tie, gapping the tie as needed.  May do that the next time around as adding these wires was a pain in the a$$.  They're 24ga stranded, but still on the big side for what they needed to be.  I wish I had some 24ga stranded with thinner insulation, that would have helped.

The irony of it is that I don't really need the wires.  I solder all my rail joiners and add feeders to every piece of track so those rails would be powered anyway. 

I suppose I did it as insurance if I decide to isolate the sidings, but running DCC, you don't really need it.

Jeff

[John]

I've cast molten lead in FUD and resin prints for a while now.  Wish I could figure out how to make a mini spin caster using them to make pewter castings.  I especially like them for specific handrail soldering fixtures.

@JeffB the prints look phenomenally accurate.  How do you like the DLP so far?

Hmmm .. maybe I can use that to make some low temp frogs to replace the mystery metal atlas 55

[Sumner]

I thought about something similar.  I was just going to drill a hole down through the PC at each rail, then solder a brass "spike" to the top and bottom of the PC tie, gapping the tie as needed.  ............Jeff

I did do something similar on one putting the wire to the bottom up though a hole but there is a limit to how much time I'll spend on this since I'm about the only one that will ever see it and hopefully it will get ballast.  Also I use ESU's 36 gauge (I believe) wire and when soldereing it and wrapping you can hardly see it with the insulation off.  I've also done it the way you have with the 36 gauge and it really doesn't show much either if painted.

Sumner

[peteski]

Hmmm .. maybe I can use that to make some low temp frogs to replace the mystery metal atlas 55

Interesting idea, but in my experience all the low-temp metals are rather soft. Not sure how durable would those be with repeated use and cleanings.

[Chris333]

Lo Temp is Bismuth.

[JeffB]

Hmmm .. maybe I can use that to make some low temp frogs to replace the mystery metal atlas 55

This is a bit of a side note...  I don't have any plans to use cast frogs on future turnouts, but I am buying metal casting equipment to turn 3D prints into brass or nickel silver.

A YouTuber I watch that has a channel that features all his 3D printing exploits, including metal casting from resin prints.  Other than the cost of the equipment, inherent dangers from working with molten metal and the fumes from burning out the resin or melting the casting metal, the process looks pretty straightforward.

Jeff

[Chris333]

Do you need to use 2 part rubber molds to cast metal, or is it done with plaster? I always hated brass castings that had a mold parting line.

[JeffB]

Do you need to use 2 part rubber molds to cast metal, or is it done with plaster? I always hated brass castings that had a mold parting line.

They are cast in investment plaster.  You put the 3D print inside a cannister, then pour in the investment.  Vacuum out any air, let set.  Once the plaster has set, you put the cannister in a burnout oven and burn out the 3D print.  From there, you take the still hot cannister (or flask), put it on a vacuum table and pour in the molten metal.

The benefit of using 3D prints is that you don't have any casting lines from a rubber mold.  But you could have layer lines, if there are any on the 3D print.

One of the key factors with going from a 3D print to a metal part is how you sprue it up.  It has to have good metal flow to all areas.  If not, you only get partial castings.

I'm looking at doing locomotive parts and a few of the more fragile detail parts for freight cars (stirrup steps and queenposts).

Jeff