RandKL's
GI Joe Modeling Page
Chariots of All Types.
Roman, Greek, and Egyptian Chariots.
This is our ongoing chariot project. I say "ongoing" because there are so many types that an entire room could be devoted to displaying them. My wife and I now have eleven of the things and we plan more.
A chariot model is one of the simplest and most easy to build vehicle models there are, and this one shouldn't take over two evenings at the most. We'll work on a simple racing chariot (biga) first off, and move on to a Roman military chariot later.
(We do jump back and forth from project to project, since sometimes it's hard to keep interest in a specific project for too long. It's better to move on to something else and to come back to the project when you're interested again....than to force yourself to finish it and risk messing it up. That said, please forgive us for not working on this specific article constantly.)
The first part of the chariot we will deal with here is the wheel construction. This same basic type of construction can be used on many different vehicles, so take your time and get good at it!
The first section is the wheel hub. The Roman's chariots at first used carved/turned wooden hubs, and later moved on to cast metals such as bronze and copper. Early chariots had very little metal on them, but later ones had a LOT of metal depending on the owner's position in society or the use to which the chariot was intended to be put.
For a turned wooden hub, we decided to construct them on a dremel mototool instead of a lathe, since our lathe just wasn't meant for things this small.
The first step.
Get some wood dowel of about 1 inch diameter (curtain rod type), and cut 4 disks about 1/2 inch thick from it. These disks will be turned/shaped into the final wheel hubs. Second step is to center a drill bit on each disk and drill a hole approx 1/16 inch in diam through the disks in sets of two....that's for your axle. We use 1/16 welding rod as our mandrel, so our hubs are drilled for that size rod at this time. Next, slip a 2 inch length of welding rod thru the holes in two of these disks and tack them with cyanoacrylate to the rod....tack, not glue them rock solid....they will have to come apart later!
Alternate method: Cut four 1 inch disks and 4 1/2 inch disks from 1/4 inch thick modeling plywood and laminate them.
The next step is to turn/shape the hubs to roundness and to approximate this pic. 
The alternate method...
The next step on the wheel construction is adding the spokes.
For this step, you'll cut two, 3 inch disks out of 1/4 inch modeling plywood. Measure and mark the center with a compass and measure a 1 inch diameter circle around that point. That circle will be where your hubs rest. Around that center circle, place 4 more circles of 1 inch diameter and begin cutting them out carefully with an xacto knife or hole saw. Carefully round all the edges except the outer rim, with fine sandpaper. The finished product will look like this
Roman racing chariots almost always used four axeblade shaped spokes on 18-24 inch diameter wheels according to most of the contemporary sources. War chariots tended to use six spokes made from turned wood or sometimes even metal. Since greater wheel diameter equals greater weight, racing wheels back then, just as now, were as small as possible. Larger diameter wheels, however, mean greater mobility and maneuverability on rough ground so war chariots' wheels often approached three feet in diameter.
The wheel rim is next.
The original early chariot wheels were made up of solid, carved arcs of wood held together with wooden pins, with a thin band of bent hardwood pegged on as the rim. That example is so difficult to make that we decided to go for the later style of metal banded rims.
For this part, you'll need a food can of about 3 inch diameter or the same size as the can you used to draw your spokes. Look around and you'll find one. Our local grocery store carries a brand of roast beef in 3 1/4 inch diameter cans that I prefer using. Any can will work as long as it's approx 3 inches in diameter, made of steel, and solid....the type with the rolled seam down one side won't work!
You'll need to use tin snips or an old pair of scissors to cut the individual bands from the can....cut two of them at right at 1/4 inch wide.
If the can is slightly larger than your planned rims, you can shrink them by using a propane torch to heat them red hot and let them cool over and over. Keep test fitting them and shrink them until they are just too small to fit onto the plywood spokes when they are cool. If the can is slightly smaller than your planned rims, you can stretch them by carefully beating them with a hammer. Again, the intent is to make them just slightly too small to fit onto the spokes when cool.
Next, use needle files (rat-tail files) to dress the rim's edges and get them good and straight. Once you're satisfied that they look good, use your propane torch to heat/expand them and carefully press them down over your spokes. The intent is that the rims contract as they cool and grip the spokes tightly.
Tip: Lay the spoke pieces face down on the table and press the rims over them from behind....if the rims burn your wood, it'll be hidden on the back of the finished wheel.
Once your rims are in place, put one hub piece on each side of the spoke piece and tack them together with cyanoacrylate. Slip the three pieces onto the welding rod axle to keep them centered as you glue them! Make sure it's solidly glued because you will have to drill them for the axle!
The second to last step on the wheels, is adding the rivets that held the hubs/spokes all together. Use soft metal craft pins from your local Walmart or hobby store. Drill holes around the hubs that will hold the pins snugly, and push them through from the face side....cyanoacrylate them on the backside and trim them off.
Last step is to jerk the welding rod mandrels out of the centers and use those holes to center a 1/4 inch drill bit as you drill them for the axle. The axle we use on this model will be 1/4 inch diam wooden dowel from your local model/hobby shop.
The next step will be the chariot itself, working from the bottom up.
Get some good modeling plywood or basswood from your local model/hobby store....we use 1/8 inch thick Sig Lightply....and cut a piece out to match the pattern number 1. Thats the floor. You want to pick the side with the best grain as your upper side since it will be visible.
To lay out this pattern, take a compass and draw a 5 inch diameter circle on your plywood. Use a ruler to draw a verticle line down the middle, and a horizontal line crossing it to mark your center. Now use your ruler to extend the sides of the circle downward to a point that it hits a horizontal line across the bottom of the circle as in this pic.
Next, mark a horizontal line exactly half the radius (1 inch) below the center point, as shown in that same pic. Now to finish the floor pattern, you'll draw a second 4 inch diam circle below the first so that the edge falls on that 1 inch mark on the first one. Connect all the lines and carefully cut it out as in this pic.
Now use a steel straightedge as a guide and scribe several lines into that floor from the front edge to the back with an exacto blade....that will simulate individual boards. Make them random width....don't bother measuring them.
The next step will be the cross support beam. Use 1/2 x 1/8 inch basswood strips from your local model shop. This beam will be centered directly on the center point of your original 5 inch circle, and extend to each horizontal edge as shown in this pic....your axle will be directly under this, under the floor. add the tree support the exact same way, but centered vertically.
Add craft pin rivets as you did for the wheels, and you're done with the floor.
Next, use your snips or scissors to cut strips off your steel cans approx 1/2 inch wide....you'll use a few of these. This half inch steel strip will be used to make your axle/tree brackets as well as the support brackets for the upper chariot and railing.
Tip: After cutting the strips from the cans, heat them red hot with your propane torch to burn off any coating the can may have. Use a hammer to gently tap them out flat and let them cool. The natural steel color and small hammer marks add realism to the scale metalwork.
For the axle and tree brackets, use a 1/4 inch drill bit as your mandrel and crimp the strip of steel around it tightly. Then carefully spread open the strip ends and bend them to form the riveting flanges. Trim them off so that the flanges are about 1/4 inch long. The finished product should look like this.
You'll need two of the axle/tree brackets for the axle, as well as two for the tree. You'll need approx ten of the L supports.
As the final step in making the brackets, you'll need to drill them for your craft pin rivets and attach them all with cyanoacrylate. These pics show the placement. (Leave the L supports off til you get the chariot body attached later!)
(Measure and mark your axle brackets so that they are perfectly even and spaced where the plan shows....this insures proper balance and allows the wheels to work as they should. Once you've got the locations marked, remeasure to be sure before gluing :) Next step is to drill rivet holes thru the chariot floorboard to match the rivet holes in all the brackets.)
Once the brackets are all glued and riveted in place, buff the floor gently with fine steel wool and stain it as you wish. A teaspoon of instant coffe in a bit of water works nicely and gives a good aged finish. You can also swab the coffee or tea stain onto the floor and CAREFULLY steam it off with your propane torch to "distress" the wood. Finish it off by buffing it with the steel wool again and you're finished with the floor again.
The next section will be the chariot body. For this section, we use 1/16 X 3 X 36 Sig basswood. Balsa is ok if that's what your hobby shop carries, but get the firmest/hardest balsa you can!
Begin by cutting one of your basswood boards into 6 inch lengths and CAREFULLY glue (cyanoacrylate) them side by side (edge to edge) to make a wide piece of wood with the grain up and down as in this pic. The grain has to be up and down to allow us to bend it.
Once you have a piece big enough, use a long steel straightedge and an xacto knife and get the bottom edge perfectly straight. Next we mark our pattern on it.
Begin this by lightly marking a 6 inch diam circle perfectly centered on the wood as per the pic. Next, do two 3 inch diam circles on the ends of the wood as in the pic. Now draw two straight lines from the tops of the smaller circles to the top of the large circle....this is your basic pattern.
The finished shape of the chariot upper is totally up to you....I myself, prefer to angle the sides directly down from the center, and skip the side circles completely.
Now put a small pot of water on your stove to boil and lay that piece of wood over it to steam slowly. You'll see that the piece curls naturally as it warms up.
Tip: Gently wrap the steamed wood around a food can of the same exact 4 inch diam you drew the floor with, and rubber band it into place....once it cools and dries, it'll be perfectly curved to fit your floorboard.
Once it's cool and dry, buff it with fine steel wool and simply cyanoacrylate it around your chariot floorboard you made before. Be sure it's centered on the floorboard, and over hang the floorboard edge by about 1/16 inch to allow you to sand it flush later.
On the original biga chariots, the body was secured to the floor by wooden pegs around the base....if you build ship models, you know them as tree nails. We can recreate the pegs very easily, but we decided to go for the later riveted look on our model.
Now take a tiny drill bit of the exact same diam as your craft pins, and begin CAREFULLY spacing and drilling rivet holes around the lower edge where it meets the floor. Don't worry about drilling into the floorboard itself....just drill them a fraction of an inch deep so the rivets appear to be holding the floor from the outside. Now cut the heads off a few craft pins and CAREFULLY cyanoacrylate them into the holes.
The final step is to add three vertical support beams to the inside of the body, exactly like you did the floor. Use 1/4 inch x 1/8 inch basswood strips.
Most bigas had bent wood handrails on the side of the chariot to grab onto as it swung around corners....some only added the grab railing to the inside side (the left side of the chariot), since the chariot always turned to the left.
Bent wood is easily done, but it takes a LOT of practice and luck to get good at them....so we'll recreate them with bent steel welding rod instead.
Use 1/16 inch welding rod, and find something hard to bend them around to get a uniform curve each time. We have sections of brass bar stock in diff diams that we use for bending wire. This pic is of the basic shape....you'll need to work out your final shape and test fit them to be sure. Don't be afraid to be creative....one existing painting shows the rails formed into dolphin shapes.
Once you've got them bent and test fitted so they match the chariot sides, begin wrapping them tightly in some thin leather lacing....the leather will cover the steel and give it a realistic leather-wrapped look. Now tack them in place on the inside of the chariot body, with cyanoacrylate....and make some support brackets for them out of your 1/2 inch steel stripping from before. Craft pin rivets through the body and the support brackets finishes them up.
The tree is the next step, and you can do it the same way you did the axle and handrails. Cut it out of 1/4 inch wood dowel, sand it then bracket/rivet it to the underside of the chariot floorboard....bracket and rivet the T crossmember on the front end with two "eye screws".
The final lengths of your tree and cross member are up to you, but the tree should extend forward enough that there is approx 5 inches from your horse's back legs to the front edge of the chariot. Imagine the horse's feet kicking back on each step and you see the reason for the gap. The final length of your cross member should extend the sides out to the outer shoulders of the two horses.
Once your cross member is cut to the right length for the horses you decided on, center an eye screw exactly where the horse's chests fall, in the top of the cross member. Those eye screws will hang from your harnesses.
Now we attach the wheels. Take a length of 1/4 inch dowel for your axle and sand it down well....polish it if ya can. Approx 1 inch from one end, drill a 1/16 inch hole through the axle for the inner wheel pin. You'll use 1/16 inch welding rod for these pins so cut a few approx 1/2 inch long. Now put one wheel on the axle and drill another pin hole on the outside of that and pin it into place. Slip that through your axle brackets on the underside of the chariot and do the same for the opposite side wheel. Your wheels should be approx 5.5-6 inches apart when finished.
The chariot is now complete except for the leather harnesswork, and that's up to you ;)
Paint it and finish it as you like, and congrats on your first custom vehicle!
The biga (racing) chariot was a one man chariot built as light as possible for speed. Its wheels where approx 2.75-3 feet wide, whereas a military chariot was a standard 4.75 feet (4' 9") wide at the wheels. Where the biga was light wood, the war chariot was heavy wood with reinforcing metal plates to protect against damage.
Our next project in this section will be a Roman war chariot.
Begin by making the hubs exactly as you did in the last one...but in this one, the finished wheels will be a tiny bit larger diameter (3.5 inch). We'll finish these wheels by adding a metal rim exactly as before.
For the spokes, you can go for the axe-blade/lightply types we used before, or for turned dowel type spokes. It's totally up to you.
For the axe-blade type, draw a 3.5 inch circle on your 1/4 inch thick modeling (Sig lightply or basswood) wood and draw a vertical and horizontal line to mark your center.
Next, using your compass, place the point of the compass on the spot on the edge where the horizontal line is and arc out the exact same 3.5 inch diam circle through the center as in the pic.
Now put the point of the compass on the edge of the wheel where that arc hits the edge, and draw the next arc.
You eventually end up with something like this.
The floorboard is made up of 1/8 inch thick Sig Lightply and scribed exactly as before to simulate individual boards. It's done exactly like the biga pattern, but with a 6.5 inch diameter circle instead of the 4 inch one. Also, place the axle and tree supports exactly as before, but add a second cross support approx 2.5 inches in front of the first. Be sure to craft pin/rivet everything securely.
Instead of just two axle brackets, you'll bracket it the entire width of the floorboard....ours took ten individual brackets side by side.
For the chariot body, we used 3/16 basswood cut into roughly one inch strips/boards and placed side by side around the floorboard and glued into place exactly as before. (Edge glue the boards, steam and bend them, then sand and buff them before gluing onto the floor.) Use 1/2 x 1/16 inch basswood strips for the vertical supports and space five of them around the inside of the body once it's in place.
Wheels and tree attach as before.
The outer covering of our chariot body is etched brass sheet that has been hammered and polished to simulate wear....and it's riveted securely to the boards under it. For the decoration, its up to you to decide. We decided on the St. Catherine's Wheel motif on the chariot and shields because it has special meaning to us. The bone and horn details are all real bone and horn, needless to say. The two gladius type swords are real steel blades with bone handles. The pylum is steel with a polished wood shaft.
The inside of our war chariot is done in alternating black and red felt to match the outside paint, and the detailing is done with etched brass strips.
The final step is painting,weathering or polishing depending on your idea of the finished product. We decided to go for the well used war chariot look, and placed appropriate accessories inside/around it.
Congrats on a job well done!