Chris's Build of Steering Engine

[cnr6400]

 

[steamer]

For those who want to pursue Chris' gear spacing tool further, watchmakers call it a "depthing tool".  There are other mechanical designs but they all work with the same principle - fine adjustment of the gear mesh and then the shafts on which the gears ride can be used directly, vis sharply pointed ends, to mark the location of the axle holes on the bedplate.

Steamer needs to provide a bit more explanation.  Toolmaker's buttons can be used to precisely position one hole relative to another but how do you determine the right mesh dimension ?  Are the gears mounted to the buttons somehow ?

That's exactly what I mean.    Sorry I responded from work and could not elabora

Post #443

https://www.modelenginemaker.com/index.php/topic,237.440.html

Here shows me using tool makers buttons to locate a set of gears for machining the gear shaft bearing holes.   
The very rough location for the hole is drilled and tapped for a small screw. ( smaller than the hole....)  The purpose of this screw is to hold the button in place
Then the button, turned to fit the gear bore, is attached and the mesh of the gear adjusted by moving the button around.   When you have it where you want it, tighten the screw.   Then slip the gear off the button.   Now you have the exact location that your looking for.    Tram the button in to being on center with the mill spindle, or lathe spindle and machine your hole.
Size the holding screw so that it is small enough that once machined the threaded hole is removed.

Dave
 

[steamer]

Tool makers buttons are generally cylinders, but they don't need to be straight sided,  they can have shoulders too.  It can be any round cylindrical shape you like, but makes sure they are round and the ends are square to the diameter.

Dave

[crueby]

Got it!  Always a number of different ways to do any task. Thanks for the explanation.   

[steamer]

The nice thing about this method of locating gears is if they are not quite perfect....you dial out the error.

Dave

[crueby]

Some more nickel plating, got the second gear done. Again, the area at the hub/spokes will be painted black on both, the outer rim/teeth left the plated color. I am going to wait on the small spur gear since it still needs some shaping at the hub. Right now, the engine bed is in getting nickeled (and dimed?)


I've started shaping the vertical plates that I got rough cut and bolted together yesterday. Started wiith trueing up the bottom surface:

Then both side faces to get it to final width:

Next will be to take the top to final height, then will do the angled sides.

[crueby]

Got the top end of the wall plates milled back to size

Then was about to remove it from the mill to shape the angled sides, but realized it was the perfect time to drill/bore the holes for the shafts since it was already squared up on the table. Found the centerline, measured up from the bottom face, and drilled the two shaft holes and the 2 crossbar holes through both plates. The lower shaft hole was bored out to size - I took that one wider than needed for the bearing, since I want to put in an insert there that sticks out from the face and has the gussets already on it.

The upper shaft hole on the front plate is set, but the upper hole on the rear plate needs to be larger to take the outer shaft that the spur gear is part of. So, had to take off the front plate from the stack, re-align the plate, and bore the hole in the rear plate out to size. Here again will be putting in an insert.

In the background, had the engine bed in the plating tank. That was a slow process, given its size - had to keep moving the nickel donor rod around in the tank to get even coverage since it deposits more metal on areas closer to the rod. Aside from the raised bosses, the rest of the base will be painted.

[Michael S.]

Chris, I think with the spokes in black the gears will look nice. As in the original.

Michael

[cnr6400]

 

[crueby]

Thanks guys!  I'm going to paint it like the ones in your pictures, green and black, its a great look.

[Roger B]

That Nickel plating is an interesting process    I'm still trying to keep up with the progress     

[crueby]

That Nickel plating is an interesting process  I'm still trying to keep up with the progress 

Great to have you following along. I did a thread on the nickel plating back a while, its not hard to do and the materials are cheap and easy to get. I don't think I'll need to plate the vertical walls, the parts that would show steel will be soldered on, like the engine mounts/crosshead guides.

[crueby]

This morning finished up the outside profile by trimming the angled sides to dimension:

Couldn't resist setting up the walls to see how they look on the base:

There are extensions at the bottom corners that help stabilize the walls in the front/back direction. Those will be silver soldered on later, but I needed to notch for the parts now while the plates are full thickness and can be clamped in the vise better. The walls will be thin after recessing the sides.


Also a notch for the bracket to hold the clutch handle on the front plate only

Sketched on the openings to be recessed into one side of each wall. The patterns are different on each wall.


And set up to start the milling of the recesses. I'll take out the bulk of the material with a normal end mill, then do the finish cuts around the edges with the radiused end mill cutter. The parts around the holes will need to be finished up on the roatary table.

[Michael S.]

The first sample line-up is very convincing. We can see how it grows.
Now the chips will fly again.

Michael

[crueby]

With the plates full thickness and no recesses, at first the gap between the plates looked very small! Going to be some tight spaces to get the pipes and valve hooked up.