When I was researching this project, I ran across a very neat operating antique steam roller. The design of this wood steam roller is very similar to the operating model....
I always enter paper patterns in Sketchup. It helps me to understand the design, and most patterns have at least one error in them...........which is usually revealed by sketchup.
This probably won't be my final paint scheme, but I picked some colors to help distinguish the different parts on the steam roller.
In Sketchup, you can create an animation. I thought it would be neat to show the parts being assembled in a YouTube video. As far as order of assembly, I sort of started at the front, then worked my way backwards...............this is probably not how I will actually assemble this wooden steam roller.
I still draw in Sketchup Vers 7, but to make the animation for Youtube, I opened the file in Vers 2014, and saved the animation as an .mp4 file. I imported the .mp4 file into RealPlayer video editor, added the title pages, and added the .wav train whistle. I saved the movie as an .mp4 file, and then uploaded it to YouTube.
I decided to go with a natural wood color on this model.
I also decided to scale up the pattern 2x, to give a big steam roller about 20 inches long! My grandson should enjoy this size of steam roller. The size matches another wood fire engine that I previously made.
I decided to make the body out of cherry. When I am done, the difficult decision will be to give it more red color with red oil stain, or leave it natural to change color over time with a mineral oil finish.
The wheels will be red padauk, and the wheel spokes with be yellow yellowheart wood. The smoke stacks will be dark purpleheart wood.
Since making the wheels looked like the most challenging part of this project, I decided to make them first. I also decided to make the larger rear wheels first.
I was going to cut the wheels from glued up 5.5 inch wide padauk, save the inside waste area, and cut the smaller wheels from that. But, since padauk is so relatively expensive, I decided to glue up 8 segments to have less waste.
I set up a stop block on the miter saw, using a 22.5 degree angle, to assure each block was the same length. This worked well. I used the string and nail method to glue and clamp the segments.
For the big outer wheels, I made 3 blanks each 3/4" thick, then one blank 1/4". I had issues with the 1/4" thick blank staying glued while I scroll sawed it. I had to re-glue it, and switch to a thinner blade. On the 3/4" thick blanks, I used a "pinned" blade to cut the thicker stock faster............it broke the glue joints on the thin 1/4" thick piece.
I cut each of the 4 blanks to the line on the scroll saw. I came up with the fixture below to clamp up the 4 blanks...........
At this point, I am not sure how I will sand the ID and OD of the glued up blank...........will have to experiment with it.
I glued up the blanks to make the 2 inner spokes required for the 1st big wheel................I am not going to cut the OD of the spokes until after I get the outer wheel done on the ID............to make sure I have a good fit.
I chucked up the big wheel OD in my lathe, with the jaws expanded against the ID of the wheel. I rotated it by hand, and I was way out of round. Investigation revealed I had one of the 3 chuck jaws not engaged the same as the other 2 jaws. I took all 3 jaws out, matched them to their numbers, and carefully re-installed the jaws. This fixed the problem.
I used the small carbide skew chisel that I turn pens with to kiss and gently turn the OD, just enough that the surface was mostly flat. I will mark #1 jaw on the blank when I remove it.
When I get get big wheel #2 done, I will turn it...........then try to match the OD's of the 2 big wheels as close possible. Then turn the ID's of the 2 wheels...........then match the spokes to the ID's.
I went to Rockler's web site to order some more yellowheart wood, and they are out of stock!! I guess I won't be able to finish this project until they get some wood in stock. I have already made the blanks for the inner spokes of 1 big wheel, so it is to late to change wood colors. I was able to order some more red padauk and cherry.
My old 1939 wood lathe chuck will not go big enough to chuck the big wheel on the OD. I tried to turn or bore the ID, while 1 side was chucked on the other ID. I decided this was too dangerous............I could not tell when my lathe tool was getting to close to the chuck jaws. I ended up putting on the 3" long drum sander on the drill press, and just sanding the ID as best I could.
I set the rim down on the spoke blank, and pencil traced the actual ID of the rim.........then sawed the yellowheart to match. This method worked pretty good......
I had just enough yellowheart wood to finish the 2 big wheels. I will have to wait until Rockler gets some in stock, before I can finish the front roller.
I just glued up the big wheel spokes, they seem to be a good enough fit that I am not nailing through the rim into the spokes.
It will take 7 segments 3/4" thick, and one 1/4" thick to make the 5.5" inch wide front roller. I have enough Padauk in stock to make the rim.
When I was sawing the short pieces to make the segmented blank for the roller, one of the pieces "blew-up" on the miter saw. I suspect I wasn't holding it down firmly enough, and it bound up. I switched to holding down the short piece with my table saw pusher instead of my fingers, in case there were any more explosions.
I had no issues making the blank for the roller. I used 7 blanks each 3/4" thick, and 1 blank 1/4" thick to make the 5.5 inch wide roller.
This one was a little bit of a challenge. On the original model, the piece was small enough to cut the curves on a band-saw. My 2X scale model, had an 8x8 inch size roof, that will not fit in my band-saw. To make the top curve, I used my old Stanley plane to get it close to shape, then I used my Harbor Freight belt sander to finish the shape.
So, the top of the roof turned out to be pretty easy to make. But, the bottom was more of a challenge. They made old wood planes with the right shape, but I don't own one.
I decided to remove most of the material using the table saw. Then I used my 3/4" by 3" long drum sander to get both ends to the finished shape. For the middle, where the skinny drum sander would not reach, I used my huge 4" diameter drum sander to get the middle shaped up.
Rockler was out-of-stock on yellow-heart wood, so I found some on Ebay. It arrived, and I made the 2 spokes for the front roller. The plan calls for them to be 1" thick, but to save expensive wood, I made mine 3/4" thick. I used the oven at 115F to help dry the spoke glued into the wheel.
All the pieces (except for the top smoke stack type pieces) are now completed, except the main body and steam boiler. I am out of cherry wood, so I can make those until I get some more cherry wood. I also finished the top smoke stack pieces.............so the only thing left is the main body and boiler...........
To conserve the expensive cherry wood, I decided to make the 3.5" diameter boiler which is 10" long, from gluing up 8 angled segments of cherry. I made the cherry blanks 9.5 inches long, so I can trim the ends about 1/8"...........plus add a 3/4" thick piece of cherry on the front. The table saw angle setting is 22.5 to make the 1.75" wide cherry blanks.
On the back end of the boiler, I will glue on a 3/4" thick piece of pine. This will fit onto my lathe screw chuck. When I am done, I will saw off the pine.
I glued a 3/4" thick piece of cherry on the front of the boiler. I glued on a piece of scrap 3/4" thick pine on the back. Not shown above, but I also glued on a 3/4x3/4x1/4" piece of pine on the front..........for a place to drill a hole and let the lathe live center run in. After I get done turning the piece to the right diameter, I will remove the little piece of pine on the front using the radial arm saw.........and will also remove the pine at the back.......to net a 10 inch long cherry boiler.
The pine on the back is so I can screw in the piece from screw chuck, to drive it in the lathe.
I sharpened my old steel gouge, and it worked well on the OD. When I got closer, I used my smaller gouge and chisel from my pen making kit......to give more control.
After I got it turned to rough size, I sanded in the lathe using 60 grit, then 220 grit. I used my card scraper to remove some turning marks that would not come out easily from sanding.
Making this out of solid cherry would require a lot of expensive material. I came up with an alternate design, that uses cherry on the outside, and common pine inside.
I intentionally designed the coal box with the edges overlapping by 1/8". Then after the box was glued up, I could use a flush trim router bit to make the edges blend perfectly. This worked very nicely. This big 1/2" collet size flush trim router bit was brand new, so it worked fine. You have to watch these bits, if they become dull, they can grab and throw you work, including bruising your hand.........as I learned in the last year of so.
The steam boiler is 3.5" inch diameter, and inserts 2 inches into the coal box. My options were to try to bore this on the lathe, or buy a special 3.5" diameter Forstner bit............I chose to buy the bit. It is the biggest Forstner bit I have ever used.
With larger diameter Forstner bits, you must put the work piece in a vise, that contacts the center column of the drill press, so it can not grab and rotate on you. I used the slowest drill press speed, but ended up increasing it by going up one size on the motor belt pulley. Slowly, but steadily, I drill a perfect hole. I took the drill coal box, and checked the size of the boiler for a good fit. I sanded a little off the boiler OD on the lathe, and I got a perfect fit!
I changed blades in the band saw from 1/2" wide down to 1/4" wide, so I cut the desired radius. I used my biggest old wood clamp to hold the round piece, and keep it from spinning. This worked great.
The fork that holds the steam roller, needs enough contact area to support it under the boiler curve. Because my boiler is hollow, there is not enough support material. I will have to add some spacer boards to properly support it. I thought this could be a problem when I designed the hollow segmented boiler, but figured I could add some wood if required.
You want the vertical hole, to be vertical on the boiler............when the boiler is at its correct angular position. I used a big wood clamp, and my digital angle finder, to make sure I had the proper orientation before I drilled it............
I put each of the 3 components on the lathe, then used a pencil to make a small circle. The center of this circle is where I drilled the components on the drill press.
I wanted to verify the steam roller assembly would be horizontal, after the front roller was installed. I assembled up the 2 front wheels, so I could measure where the center of the Roller should be on the front roller arm assembly. I used the digital height gage to make sure the whole assembly was horizontal. The height location of the center of the roller, on the front roller arm assembly, came within 1/8" of the design drawing........which is not too bad!
My grandson loves to assemble and then take apart the toy over and over again...........so I tried to make this Steam Roller so some of it can be taken apart. Of course, I don't want any small parts that are choking hazards either. This led me to the following design decisions.......
1. The whole front roller and arm assembly can be lowered from the main assembly.
2. I found some steel retaining pins at Ace Hardware, that will allow the wheels and roller to be removed from their axles. One side of the wheels has a fixed, glued in dowel on the axle, while the other side has the retaining pin.
3. The cab roof, back cab wall, and front cab wall will be half-dowelled in place (the dowel is glued into one side and free on the other side)
4. The rectangle with the 2 smoke stacks will be half-dowelled so it is removable. The smokestacks will be permanently glued in place.
1. glue in smokestacks
2. half-dowel rectangle with 2 stacks
3. dowel and glue lower steering arm to roller
4. Make steering linkage
I temporarily installed the front yoke, so the boiler would be at the proper orientation angle to glue it to the main body...........then I removed the front yoke, so I could attach the lower steering yoke to it.
The right angle joint of the lower steering yoke connection to the roller frame is a fragile joint prone to failure. I decided to put in the biggest dowel I could, which was 3/4" diameter versus 1/4".
I decided to leave all the wood colors natural, and just on a couple of coats of polyurethane. Over time, the cherry will darken.
I 220 grit sanded all the parts, then used clear gloss poly................
I ended up doing 2 rounds of 220 grit sanding and polyurethane.
I made a YouTube video showing the completed wooden model in action...........
1. takes a lot of hours to make 2 spoked wheels and rollers
2. Only unexpected issue was having to add material after cutting lower curve in boiler
3. The 3.5" Forstner bit worked very well to drill the boiler hole in the firebox
4. Intentionally adding 1/8" to the firebox sides, then flush routing them away worked very well.
5. Marking true axle center on the 2 wheels and roller, using a pencil and the lather, worked very well.
6. The steering mechanism works very well. It is counter-intuitive to adults (it goes the opposite way you turn the steering wheel), but
should not matter to children.