A while back .. a good while back .. I scratchbuilt an ore bin which was designed to take ore from an On18 line and then dump to hoppers an On30 track. I recently had a request for some of the chutes so .. this is an overview. The chutes are circled in red.
Here we have three chutes fully assembled. The gate can be installed either fully down or fully open or in between as one wishes. Was quite happy with how these turned out with even this relatively close look doesn’t show too many “warts”.
These were first sprayed with a gray primer which doubles as a base metal color and provided a base for acrylic paints and washes.
The chutes were made up of multiple bits and bobs.
- Map pin – these are great for any kind of shafting. At 0.023″/0.58mm they are a bit over 1″ in 1:48 / O scale
- Bevel Gear Vert – The other end of the shaft that runs through this gear has the operating handwheel. It seems to me that this most likely would be vertical so the handwheel could be operated from above –
- Bevel Gear Horiz – part of a two part gear assembly with a bevel gear at one end which meshes with the Bevel Gear Vert and a pinion (left) that meshes with the left rack.
- Pinions Left/Right – meshes with the rack.
- Guide Left – has a bearing for both the horizontal and vertical shafts.
- Guide Right – has a bearing for the horizontal shaft. The guides both Left and Right are stepped to allow the door to slide up and down.
- Door – Printed with the racks.
- Chute – in this version I had holes printed for NBW as (I think) I was planning to print these in sintered nylon from Shapeways. The holes in the front flange were to represent the where the guides bolted on.
Note: Often when printing something what seems like a good idea at the time turns out to be .. not. The door was a PITA as flat parts tend to warp. I had to try multiple angles to finally get a door that only warped a bit … which I had to sand down some to slide between the guides. Those guides required aligning with a pin. This was ok in the end but another PITA .. even if just a bit so. This was addressed later.
V12 – ish.
test prints and the Rack Jig and Rack
- Map pin – same as before with a 0.023″/0.58mm dia for the shafting.
- Bevel Gears and Pinion Gears the same
- Door – 0.030″ styrene sheet
- Rack – I merged the two racks into one piece that can be printed separately and glued to the door (note: need a jig to align)
- Chute – two versions, plain and ribbed. The guides are merged to the chute.
Here’s a look at the revised rack assembly. If I left the rack like it was originally as two separate racks there would have been a greater tendency to warp. Hopefully grouping the two racks into a single assembly will mitigate any warping.
In any case the assembly jig should straighten out any warping.