Horse drawn Galion road grader circa. 1913?

[crueby]

i wish you would stop showing us the photos of the full size grader you are building and show the small model instead...   

Just kidding - absolutely amazing work, as usual.

[Alan Haisley]

Still speechless ...

[scc]

Unbelievable George    and here I am struggling with 8ba and clumsy fingers. This grader goes beyond model engineering.......it's pure artistry.       I love this post, THANK YOU.        Regards       Terry

[gbritnell]

Gentlemen,
I know it's been a long time since I posted anything but that doesn't mean I haven't been working on it. Every part is connected to another part so when making one piece 1 or 2 and sometimes 3 other pieces are required.
Since my last posting I made the odd shaped wheel that eventually will rotate the blade. It's mounted to a shaft that fits inside of a tube that's welded to a formed bracket that bolts to the floor plate. Attached to the shaft is a U-joint which will connect to another U-joint a then finally to the bevel gear on the top of the blade assembly.
I had to drill holes in the floor plate to mount the wheel and bracket. I blued the plate and using dividers I gave myself a centerline. On the centerline I scribed the location for the 2 holes.
At this point I have a question for the members. I backed up the floor plate and then using an automatic center punch gave myself to dimples to drill to. Now here is the question. When drilling something like the floor plate after it's in place what would you use to drill the holes? (1/16, .062, 1.59 mm diameter). I use my Dremel flex shaft attachment but from past history the slowest speed is too fast and it wants to make the drill wander. It's one of those things that you just hold your breath and hope that it doesn't give you an ugly hole because there's no way of replacing the floor plate at this point.
I'm thinking of making a speed reducer attachment for the Dremel, something like a planet gear box that will screw onto the nose of the Dremel.
Anyway back to the build!
The pictures are a mix of the original machine and my replication of it.

[gbritnell]

Next up was the operators platform. The original is composed of 2 pieces of angle iron that's bent on the ends. Mounted to these angles are a series of steel slats, 7 across the flat area then 3 up each side. Apparently they were welded in place because there's no sign of rivets or bolts. I looked up arc welding and they did have it back as early as this machine was built so I suspect they were welded to the angles.
How on earth to copy this! To start off with I milled 2 pieces of angle stock. Using a jewelers hand saw I split the flat side at the angle vertex. I bent each piece to the proper angle then soldered a small plate over the split. Now how to get all those slats mounted with only 2 hands. I drilled 2 widely spaced holes in the flat side of the angle stock. I then made 2 spacer bars that were threaded 0-80 in the ends. I then bolted the angles to the spacer bars. This gave me a rigid assembly that I could mount the straps to. All the straps were cut filed and sanded prior to soldering. I scribed some lines on both angles at the center to give me a starting point. Naturally the first strap soldered just fine. It was all the others that I was worried about. How much heat would it take to solder the other straps without unsoldering the one next to it. Using 2- .078 diameter drills as spacers I butted the next strap in place and fluxed the joint. I then got my bit Weller solder gun nice and hot and touched the outside edge of the slat. It soldered just fine without dislodging it's neighbor. It even got hot enough for the solder to wick underneath and around the joint. With some new found confidence I continued soldering the slats on.
I think this part was one that caused me the most concern.

[gbritnell]

The operator's platform has 4 legs that bolt to the main frame. I made up the angle brackets and bolted them to the angles with M1.2x.25 square headed bolts. These will get bolted to the frame, eventually.
For now I just have it sitting there looking splendid!

[crueby]

For drilling small holes in thin stock I like to clamp it between two wood blocks so it can't spin or distort. If the holes have to be lined up with layout lines, will make a slightly larger hole in the top block so the lines can be seen. I don't like to center punch, since it can still let the drill skate. Instead, I've got a small center drill, with a .100" tip. That will give a wider and even  dimple to keep the drill tip centered. I've got a small proxxon drill press that gives a good feel on small drills, the mill can make it hard to feel pressure on the small bits.


And agreed, looking splendid!!!

[gbritnell]

Now moving on to the rear axle assembly.
I had everything made and partially assembled but needed to mount many of the small pieces to complete the assembly.
At the ends of the lower support angles are stops. These keep the trunnions from canting over too far when the wheels are cocked. Apparently without the stops the operator could cant the wheels to the point that they couldn't be brought back to horizontal, thus the stops. I milled them from solid leaving the small angular projection the filed it to shape.
On the upper angle is mounted the curved rack gear. On the gear box is thinner at the top than where it mounts between the lower rails so that allow the use of bolts to mount the rack gear. My gear box is the same width throughout so to mount the curved rack I countersunk the inside of the holes on the rail then soldered the rivets in place and filed them flush.
The lower rails also have 2 cast pieces that the forked arms mount to.
All of these pieces are mounted with square headed bolts and nuts. I don't even want to think of all the hours I have in just making nuts and bolts. I make them as I go because I don't know what the lengths will be until I get to that point.
Now another challenge. The shaft that turns the worm in the gear box rises vertically and is supported by an odd looking piece of formed metal. It cross section is like angle iron but at the top it has a much wider area with a large radius. This must have been designed for added strength at that point. I could just make a piece of angle stock and bend it so I made up a drawing to machine it out of solid.
I mounted the stock to the sacrificial plate on my rotary table and commenced whittling away.
The top of the shaft terminates in a uniquely shaped casting. On the end is a miter gear which meshes with another miter mounted to the crank handle. I had already made the miter gears way back when I made all the gears for the machine. I didn't want to have to continually set up for gears along the way.
The cast frame that holds the gears was something that I just didn't want to fabricate. Not that I couldn't but it's hard to tell how many I would have had to make before I got an acceptable one.
I have had parts cast at a company called Shapeways in the past and was very satisfied with the results so I made a CAD model and sent them the file. I added a few thousands to the diameter not knowing how exact the casting would be. The cast piece exceeded my expectations so it was machined and the shafts and gears fitted to it.
The bottom of the angular support is bolted to the inside of the lower rail with yet again more square headed bolts.
The final pieces were angle brackets that bolt to the top and bottom rails and are connected with bent straps. These help tie the rails together and act like a parallelogram with the axle trunnions.
The final pictures show the full sized machine and where I'm at with the replica.
gbritnell

[gbritnell]

The final set of pictures.

[gbritnell]

Hi Chris,
I understand what you're saying but I don't have the luxury of using my sensitive drill press to get into these tight spaces. They have to be drilled by hand and that's where the problem lies.
gbritnell

[crueby]

Hi Chris,
I understand what you're saying but I don't have the luxury of using my sensitive drill press to get into these tight spaces. They have to be drilled by hand and that's where the problem lies.
gbritnell

Gotcha. In cases like that, i would tend to use my high speed dental bur handpiece with a football shaped diamond tip to start the hole. At 400k rpm, it does not wander or pull. Then finish with the drill bit in the flex shaft.

[Admiral_dk]

I like Chris idea of using wood to help the drill bit to "stay in place" and will certainly consider using some of all the icecream sticks I keep for later ....

My experience is that the slower the small drill go the worse - so I like to keep the RPM above 15K when using drill bits smaller than 1.5mm - that normally stops them from wandering.

[Don1966]

George my friend that is looking magnificent it’s all I can say. .......



 
Don

[fumopuc]

Hi George, the details are unbelievable.
So my stairs at the Bruce Macbeth engine seems to be a kind of heavy metal construction against you work here.

[Brian Rupnow]

George--Beautiful results as usual. Very, very nice work.---Brian