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View Full Version : 1913? Galion horse drawn road grader



gbritnell
03-25-20, 07:52 PM
Gentlemen,
I'll start with a little history of this build.
I have a friend who lives about an hour away. There are basically 2 ways to get to his place, one by mostly interstate and the other by state routes. I usually opt for the Interstate just for time. On one of my trips I wasn't in a big hurry so I took the alternate route. At a little crossroads town, Homerville, Ohio, they have converted the old school to a community center. At one corner of the property is a concrete pad with an old Galion road grader sitting there.
As I past by I thought "that would make a very neat addition to my 1" Case steam traction engine." "I'll have to come back and do some measuring."
Well that year passed and another and every time I would go that way I would think of building a model of that machine.
Finally in the spring of 2109 I committed to measuring and taking pictures.
I have done this kind of thing before, measuring, sketching and gathering information and have found that when I return home and start turning all that data into CAD drawings I seem to be short about 500 dimensions. In all I made 4 trips to the grader before I actually had enough info to complete the original layouts.
From the layouts I start the very long process of creating working drawings. Each drawing is on the standard Imperial 8-1/2 x 11 sheet. When drawing a machine as a buildable model parts need to be modified for any number of reasons, strength, screw sizes, material availability, and gear design.
I have somewhere in the neighborhood of 600 hours in the complete set of drawings.
The scale is 1/12 or 1" to the foot. It will be made mostly from brass. I will cut all the gears and in a lot of cases make the special shaped pieces, angles, channels and bars, to build this machine.
Before I get into the model part of it I'm attaching a link to a video I took of the grader.
gbritnell
https://youtu.be/XPR19n_TwoQ

gbritnell
03-25-20, 08:14 PM
The frame is a little over 15 inches in length. I looked around for brass large enough to machine the rails from 1 piece but when I could find it the cost was extreme. At this point the build got put on a temporary hold.
One day while talking with a friend he asked how the grader was coming and I told him where I was, still looking for brass. He said that he had a chunk of brass in his back shed and it had been there for many years. If I could use it I was more than welcome to it. He dug it out and it was hard to tell it was brass. Time and the elements had turned it almost black.
I took it home and cleaned it up and it was more than I would need to complete the model. The only problem was the block was 12 inches long and I needed 15. I decided to make the frame in 2 pieces and silver solder them together.
As I was planning my attack on the frame another friend called and asked how the grader was coming along. I told him that I was laying out the material to make the frame. He has a shop full of CNC tooling and said that his machine guy was in between jobs and if I created a part model (Solidworks) he would have him cut it for me. I didn't hesitate at that offer so I created the models for the frame rails and took the brass and files down to his shop. Within the week he called and said the job was done and I could pick it up.
All of the pieces were machined leaving a .006 fin between the part and the parent metal. This simplified the machining for such an irregular shaped part.
I cut the parts free and started cleaning up the fins.
I made up a fixturing jig to hold the 2 pieces of frame together and silver soldered the joints. The next step was to make the end plates to connect the rails and give me starting point to add all the bits and pieces. A lot of the parts will be soft soldered together with rivet detail added at a later date. 35206352073520835209

gbritnell
03-25-20, 08:22 PM
There is no particular order to this build other than to make pieces that will allow other pieces to be made. I don't know how many pieces there will be but there will be a ton. The wheels were next. The hubs were turned and drilled for the angular spoke attachment. The rims were turned and also drilled for spokes. A fixutre plate was created to mount the rims and hubs so that the spokes could be inserted and soldered. 3521035211352123521335214352153521635217

MODEL A MODEL
03-25-20, 09:56 PM
Beautiful start!

Thank you for posting! Could you show us what it will look like eventually?

Roger Zimmermann
03-26-20, 12:32 PM
Don: go to the beginning of this thread, you will see it.

Interesting machine! Doing the frame that way, it will have no irregularities!

gbritnell
03-26-20, 04:32 PM
Each of the spoke holes in the rim were slightly chamfered to allow the solder to flow around it. With the hub and rim mounted on the fixture plate the spokes were inserted and made sure that they were bottomed out in the hub. The exposed ends were fluxed and using small cutoffs of solder the spokes were soldered with a small butane torch.
The first pictures show the finished wheels and the second set shows the wheels standing in their approximate location to the frame.

gbritnell
03-26-20, 04:51 PM
This machine a large number of gears, worm, miter and spur type. There are 7 enclosed gear boxes with both worm and miter types then some of the exposed gears are spur pinions with curved sections of the same pitch.
When I reduced the scale I had the dimensions for the outside of the gear boxes and wanted to maintain the proportions so the gear sets had to be designed to fit within those sizes. This meant that, in most cases, non standard pitch gears would be needed. The same thing for the worm and wheel sets.
At the operators platform are 2 large gear housings in which are a worm sets. These are used to take the rotary motion of the large handwheels and rotate long shaft that raise and lower the blade assembly. I calculated the diameter and pitch of the worms and ground a high speed cutter to chase the threads on the lathe. For the worm wheels (gears) I had to make another cutter. This one was made from W-1 drill rod. The shape of the involute curve was drawn in CAD and replicated on the cutter. After the lathe work the cutter blank was put in the dividing head on the mill and the flutes were cut into it. Using a magnifier I carefully removed any burrs before hardening.
A gear blank was made and mounted in the dividing head to cut the teeth. From my drawings and calculation I determined the lead angle and tilted the head to that angle. There is one right hand set and one left so the head had to be tilted to both angles.

gbritnell
03-26-20, 05:06 PM
When trying to replicate complex shaped parts, especially castings, in most cases it's necessary to create the part from several to many components.
This is the case with the gear housings for the worm sets previously shown. The box is basically a circular shaped part with a rounded section at the bottom which houses the worm.
Starting with a block of brass cut to the overall dimensions all the holes were put in. This is the first step in making any parts because you have square and flat sides to chuck to. If you cut the profiles first in most cases there's no way to hang onto the part for drilling or boring operations.
The worm hole was put in then the block was flipped 90 degrees and the gear cavity was roughed and finish bored. The mounting holes for the outer cover were also drilled and tapped for 0-80 screws.
With all the holes put in the block was slowly whittled away to create the shape.

gbritnell
03-26-20, 05:23 PM
When I learned my trade many years ago (metal patternmaker) We were taught to cut curved shapes using a ball end mill. This was the days long before CNC.
Each machinist had a small 'black book' with step-off charts for various radii using different radius cutters. These were valuable books considering that all the calculations (sine and cosine) were done by hand. No calculators either! Sometimes a rotary table can be used but in a lot of cases the fixture and setup time doesn't justify the tooling changes.
As I mentioned the housing has a radiused boss at the bottom which houses the the worm gear. With the major shapes roughed in the boss was stepped off.
The part was removed from the mill and the small steps were filed and polished to give the part a finished look.
The part was then put back in the mill to do the other side of the gear box. This side has a protruding boss with 3 stiffening ribs. It would have been extremely time consuming to try and do this as one setup so the ribs were cut then the housing block was tilted to cut the angle on the ribs. A small tube was machined and inserted between the ribs and soldered in place.

Roger Zimmermann
03-26-20, 05:29 PM
Well, it seems that you know what you are doing! Nice parts, by the way, and nice machines!

gbritnell
03-26-20, 05:44 PM
It was now time to machine the radius on the outside of the gear box. There was no easy way to hold it because the radius needed to go the fill depth of the box so another fixture was needed.
A piece of aluminum was drilled and tapped to hold a boss that would fit inside the cavity on the other side of the box. This was mounted to the plate with a small screw through the center hole but this wouldn't provide enough holding power even with light cuts so I made another small block with a circular cutout.
This would hold the boss at the bottom of the gear box and keep it from rotating.
The rotary table was put on the mill and the center picked up by indicating the boss. The gear box was then mounted and screwed tight.
A first cut was made down to the backside of the bolt bosses which hold the front cover in place. The second cut was down to the full depth. I had to be very careful when coming around to the features on the gear box so that no 'oops' cuts were made.

gbritnell
03-26-20, 05:56 PM
Thanks Roger,
Coming from you it's much appreciated. I've been doing this for 50 some odd years so I had better have learned a thing or two.
I can really appreciate the work you do with your machines. In my early days it was just a lathe with a milling attachment.

MODEL A MODEL
03-26-20, 06:32 PM
Oops, sorry. Iím stilling using my phone and donít get the whole thread.

gbritnell
03-27-20, 09:58 AM
The gear boxes needed end caps for the worm cavity. Each end was a different shape. One end was fairly simple but the other end needed a lot of fine work with my Dremel and riffler files. The end caps were slid onto a rod and inserted into the gear box and soldered in place. At that point a little more hand work was needed. The cover plates were turned and milled as you see. There is a triangular boss on the front of the cover which on the full sized machine is for an oiling hole for the gears. I created the boss but don't know if I will drill it or not.
gbritnell

gbritnell
03-27-20, 09:59 AM
The finished model won't have socket head screws but rather all square headed bolts and nuts which were common for the era.

gbritnell
04-08-20, 12:59 PM
With these gear boxes complete the brackets were made to mount them to the frame The brackets are multi-part assemblies made from machined pieces and parts fabricated from sheet brass. The frame rails are at 1.5 degrees from the centerline so the mounting plates had to be machined to keep the brackets parallel with the center. Most of the components were riveted together on the full sized machine but due to the issues of trying to peen the opposite end of the rivet I have opted to make small bolts with a rivet head. Where they pass through the frame they will have square nuts added to secure them.
The front brackets that the shafts pass through were machined from solid.

gbritnell
04-08-20, 01:09 PM
The front axle support is made from a casting and pieces of channel. Being as there are no castings used on this build the parts have to be machined or fabricated to try and replicate the casting. The support has a circular shape that rides on the bottom front of the frame. The circular part has a round tubular projection for a short tongue which will terminate at a gear box. Another piece which is a post also has a tube attached to it. This is for the main tongue which will go to (originally a team of horses) but later some type of machine, tractor or steam engine.

gbritnell
04-08-20, 01:18 PM
In the description of this machine it is referred to as a tilt wheel grader. What this means is that being as the wheels are flat steel rims with no center bead when they would move material, dirt or gravel, with the blade at an angle it would tend to push the machine sideways so to counteract the side force the wheel could be tilted to dig into the ground. Much like using the edge when skiing. The front axle assembly consists of the triangular support legs and the axle assemblies. There are the main lower angle pieces and the upper angle pieces. The trunnions that the wheels mount to are pivoted at the bottom angles and the upper angles rock back and forth to tilt the wheels. This action will be controlled with a gear box and it's linkage.

MODEL A MODEL
04-08-20, 02:13 PM
Very nice work! Very clean and well photographed too!

I assume that it will eventually be painted? Too bad the prototype wasn't made of finely finished Brass! That too would be something to see!

Very nice! Thank you for sharing!

-Don

gbritnell
07-13-20, 12:30 PM
Gentlemen,
The grader is finished. It was a totally different project than what I am used to building (engines, weapons etc.) Working with sheet metal is different than just machining a part to size on the lathe or mill. With a lot of the parts I would cut a piece of metal to length, bend it then see how it came out to the required dimensions. I built a small metal brake years ago and it makes pretty consistent bends.
https://youtu.be/BDkGjuT9gX8
https://youtu.be/PDwxCcs-yOo

MODEL A MODEL
07-14-20, 12:52 AM
Beautiful! Beautiful! Beautiful!

Fascinating!

Thank you for sharing!