Nathan K5LA Train Horn

When a kid spends half an hour excitedly explaining the differences between two different models of industrial signaling device to his speech therapist, in particular why one of them is his favorite, well...

I was looking for a K5LA train horn model to print, and the one posted by Manimal was very close to what I wanted but when I scaled it up I just couldn't get it to print. So, I imported it into OpenSCAD and reconstructed it with special thought given to printability. Tolerances are set up for scaling it so the longest horn is 160mm long, bolts are separate so you can easily print them in a different color from the body, and almost everything that would be a pain to print has been broken up in a way that makes it easy to both print and assemble.

How many of each component to print is indicated in the file name.

NOTE: This is not a functional train horn, it is a scale model just made to look the part.

Print Settings

Printer Brand:

Prusa

Printer: 

i3 MK2S

Rafts:

No

Supports: 

Yes

Resolution:

0.2

Infill: 

15%

Filament: Inland PLA Black/Silver

Notes:

The most difficult parts to print are the longer horns for sure, I thought I'd have trouble with a bedslinger but I managed to print them all upright on my Prusa quite well. A couple of the horns open up pretty steeply so the underside of the overhang came out a bit rough, but I find it acceptable.

Parts are not oriented, you'll have to orient them yourself. It should mostly be pretty obvious, though I do recommend printing the "horn\_base" with the hole on bottom and "base\_body" upside-down (three bracket cutouts on bottom).

EDIT (1/10/2022): Just to be clear, the STLs are neither orientednor scaled. I built it to match Manimal's model, which makes it very small. After I imported all the parts, I scaled them all together so that the longest horn was 160mm (~6 inches), this is the scale I was targeting. I might rescale the source at some point, but haven't yet.

Post-Printing

I recommend putting the bolts in with gel super glue since they just need something holding them in and there's a lot of them, then use epoxy to attach the brackets to the horns and the base for strength. Everything else it doesn't really matter.

There are two sizes of bracket. The three shorter ones are for the long horns over the top, the two taller ones are for the smaller horns on the sides.

The four base bolts and the 30 horn bolts are very close but nevertheless slightly different in size, I was just too lazy to simplify that.

That's about it! Have fun, and if you print one, please post a make!

Category: Props