Section 12 - Smokebox

Your browser has disabled scripting - some functions of this album will not be available. Please check your browser configuration and security settings for this site

Up one level

Neidrauer Adventures Photo Album and Blog » Building a Live Steam Locomotive - the Mikado Project » Section 12 - Smokebox

In Progress! The 'face' of a locomotive. Smokebox front, smokestack, headlight bracket, hinges, bell. February - June 2009. Completion on hold until assembly.

At first page

Next page

1-64 (of 86 found)

14-July-10 The parts of the 1/4-turn fast-opening gate valve on the bench. There was waaay too much slop in the valve stem - gate connection (center part), so we will make a new stem to replace it.

Turning a piece of brass with a specially ground tool to make the new valve stem. The special tool is needed to put an inside-cup face on a shoulder, which holds the rubber washer in place.

The first 45 degree bend is completed for three pieces and I sneak a picture while the fourth is bent. After this a 90 degree bend is put on the ends with the two close holes.

With the holes drilled in the bracket, the old box brake is put to service for two bends each bracket has on it. He is actually bending the 3/16

10-June-09 We start on the smokebox running board brackets. Bill has machined four pieces of stock to size and has stop set up for in the vice to make the identical pieces. This allows him to put the next piece in the vice and not have to re-indicate the location. Just clamp and re-use the same numbers on the dial!

The smokebox section is the start of several sections with a lot of little things to do. Here Bill is drilling the handrail for the headlight bracket. I still have to get the brass rod and thread both ends to put in the holes.

Drilling the holes in the sheet metal really calls for a drill press, not a mill. Since my 1930's era Barnes 14

3-June-09 Using a step drill bit to cut the holes in the cylinder jacketing. Each hole was piloted before using the drill, the advantage of this style is it does not 'grab' the sheet metal when breaking through to the other side.

27-May-09 The welded steam shrouds ready for fitting to the smokebox shell.

We center the boring head as best we can and bore the angled hole in the curved flange. We advance the cutter after each pass until it just barely reaches 2

The chuck is clamped in the vice. We want the middle of the flange (left-right when the finished part is mounted on the smokebox) to be in line with the front to back motion of the table. With the part in the correct orientation and supported by parallels, we indicate the one jaw and rotate the chuck around until we can move the table l-r without any change in reading.

We decide to use the 3-jaw chuck. It has tall enough jaws to allow for the 1

27-May-09 After rolling the shroud flange the 2

We used my antique roller to roll the casing and casing flanges. These are 2

The casing parts

A trial fit of the steam pipe casing.

Cutting the outside of the steam pipe casing flange make chips fly all over our faces (ouch! hot chips), so we clamp a piece of plastic in front to deflect them.

13-May-09 Preparing the Steam Pipe Casing Flange for boring.

120 Rivets later, the smokebox shell has all the decorative rivets in place. This was actually fun to do!

13-May-09 Satisfied that the hinges are correct, we rivet them to the front cover.

With temporary bolts holding the hinges to the front cover and the shell, we test the hinges -- And the work smoothly without any binding or excessive slop! Yea!

Turning down a piece of O-1 oil-hardening tool steel to make a riveting buck.

The convenience of a second machine in the shop. Without disturbing the setup in the big mill, we use the mill-drill to drill the front cover hinges, relying on a parallel and the flat surface of the casting for alignment.

6-May-09 With the hinge pin holes drilled in the shell hinges, we set the front cover hinges in place and using a transfer punch mark where they should be drilled. You can also see in this picture the socket-head screw we put between the two hinges. Because our shell hinges did not end up exactly where the print calls for them to be, our front cover hinges actually cover the two front bolt holes, rendering them ineffective. Our solution was to fill the holes with dummy bolts like the rest of the front cover has and just put one new one in the shell.

There was no way to reach the bottom hinge - not enough quill travel and too many things in the way. We had to turn the shell over and cut from the 'underneath' to finish the bottom hinge.

4-Apr-09 We also decide that the little end mill we used to cut the slot in the hinges did not cut deep enough. We re-bolt the shell onto the table and using a slitting saw finish the slots to the correct depth.

4-Apr-09 Looking at the smokebox front print, we realized we did not turn it to the correct thickness and put the relief step in the back. So back onto the big lathe it goes again.

Using a resharpened carbide bit (the only way I can afford carbide cutters are by getting used ones) we oh so gently cut the back of the hinges. After a single pass we could see the hardened parts of the hinge which tore up the drill bits earlier.

We decided to lower the front hinges to make it line up better with our thicker front and the shell hinges. Here they are clamped to the table.

1-Apr-09 We tried to use the regular drill chuck in the mill, but with the long drill bit and the table all the way to the bottom, we couldn't make it work. We ended up using a small chuck held in a collet.

Using the wiggler to get the outside reference surface.

Using the milled surfaces for reference, we bolt the shell to the table and align it to vertical using the combination square. It is a pain clamping the shell down (on the inside), it rolls a little each time we tighten the bolt.

The 1/8

Using a larger ball-end mill, we finish the lower hinge support. We also skim the outside of the hinge to get a vertical reference surface.

We start by just skimming the outsides of the hinges to get reference surfaces

1-Apr-09 With the shell hinges temporarily bolted on and the smokebox shell held down on the table vertically, we use a carbide ball-end mill to cut the bearing surfaces on the hinges.

We figured the only way we could hold the shell hinge brackets was to rivet them to the shell then mill the slots, insuring parallelism to each other. Here we bolted the shell to the table again and using the wiggler to line the shell up with the top and bottom marks on the shell (back and front on the table).

The supplier now provides these brackets in aluminum only, due to the case-hard skin these thin sections have. We chewed up a HSS and a TiCN coated drill bit before finding a small Carbide ball mill we could use. Even though this little mill had one damaged flute, and really wasn't a center cutting mill, it chewed through the tough cast iron without complaint. Sometimes it is all about getting the right tool for the job, and in this case, it is carbide for cast iron.

Now to drill the rivet holes. We lift the brackets off the table with a parallel and clamp away from where we have to drill.

Using a ball-end mill, we clean up and machine the hinge tabs. Since these brackets are cast iron, we use a carbide mill. I think the results look good!

28-Mar-09 The smokebox front hinges are easier to clamp, just line up the straight side with a square to the vice.

Another clamping conundrum, how to hold the bracket to the shell to match drill the shell holes to the bracket.

25-Mar-09 These smokebox shell hinges are just plain hard to hand onto! Here we are making a cleanup cut on the shell bracket portion to fit nicely up to the end of the shell.

We have not removed the alignment block (left) from the table since drilling the other holes in the shell, so we just roll the shell around to line up the punch mark and then drill.

18-Mar-09 Laying out the decorative rivets the old-fashioned way: Layout dye, calipers and a center punch. 4 done, 116 more to go!

Success! With the handrail, headlight and bell holes drilled in it, the cover fits on the shell without needing adjustment.

Drilling the handrail holes.

Drilling and tapping for the headlight bracket.

Running the same bolt circle program with the same dimensions as the smokebox shell, we hope everything lines up during assembly. We find some radial differences in the placement of our holes and the casting marks, when all was done, the cover and shell lined up properly.

11-Mar-09 With the back of the smokebox cover marchined, it is time to drill some holes. Setting the cover on the table, we indicate the outside to center it. We tried this without clamping at first so we could swing the whole diameter uninterrupted, but we couldn't put the clamps on without moving it. This cover is also at the limits of my table travel, we had to move the Ram out to reach both front and back holes.

I've been running the numbers for the RRS heavy mike I'm building and finding differences between what is drawn and what I calculate. I'm not trying to second-guess the draftsman, just how to best set up my blast nozzle/petticoat.

I have done the calculations, drawn the 1:6 and 1:3 cones, and found significant differences making me wonder if I am doing something wrong.

If you don't mind, I'd like you to double-check what I have figured.
Cylinders: 2.375

The big question: Do all the bolts holes in the cylinder saddle fit nicely with the drilled and tapped smokebox holes? Answer: YES! we could start all the bolts by hand, indicating there was not interference.

Here's what the smokebox shell looks like after 24 iterations (about 4 hours) of align, drill and tap operations.

Two holes down, 22 more to go. Here's how it went: Using the pointed wiggler, line the punch point on the shell up under the spindle. After checking the front and side alignment with a magnifying glass, bolt the shell down and check the alignment again. We found the shell moved slightly each time we tightened the hold-down screws. Keep adjusting until things are tight but still true to the punch mark. Center drill a hole, Tap drill al the way through, Tap for for a 10-32. I wanted the extra security of a threaded hole in this nice thick smokebox shell instead of just a through-hole nut and bolt assembly. After that hole is done, loosen the clamps, rotate the shell until the next punch mark is on top and repeat: wiggler, center drill, tap drill, tap.

The transfer punch. For these holes under the cylinders, we put a piece of stout steel bar on the punch and the other end on the table. Using a 3 lbs. hammer, quickly strike the steel bar as close to the punch as possible, transferring the center mark.

With two holes drilled and tapped, we put temporary bolts in to hold the cylinders to the shell so we can punch-mark the rest of the holes, insuring the cylinders do not move during the punching process.

Using a homemade close fitting transfer punch, we mark two holes in the shell then remove the cylinders. We use the wiggler to line up the head exactly over the punch march, rolling the shell around until things line up. We do not ever move the X-axis (l-r) to position the hole.

With the right (or wrong) light, the scribed center line and casting halves mark almost disappear.

28-Feb-09 The painted cylinder saddle is brought down from the cold garage and into the shop to match drill it to the smokebox shell. We have scribed a center line on the shell to match the casting halves joint, and another line where the center of the front row of bolts should go to position the saddle front-to-back properly.

Another Saturday of bad weather means more time in the shop and less out at the track. Good for shop time, bad for getting the track ready for the April start of season run. Using the eyeball

Page 1 of 2

Next page