How To Make DIY O Gauge Trucks And Wheels

If you're like me and you buy small lots of trains for parts and restoration, you inevitably end up with lots of cars that are in need of trucks. But a new set of trucks can cost more than what you paid for the car. So what do you do? Hello again, this is Mike with another episode of Toy Train Tips and Tricks. About two and a half years ago now, I published a video on how to use a 3D printer to make your own freight trucks. That design was functional, but basic. And now that I've improved my design I thought it was time for a new and improved 3D printed freight truck for my railroad. My original design lacked four things. First of all, it lacked weight. Being fully constructed from PLA or PETG plastic, these trucks are featherweight and so I must be careful about where I place the cars with these trucks in the train. Second, the plastic-on-plastic junctions create a great deal of friction, so these trucks don't roll very well. Also, the trucks are inconsistent. A bit of filing is necessary to get the axles to fit properly in the side frames. Too little clearance and the wheels don't turn. Too much clearance and the axle is snoppy in the frame, causing derailments. And lastly, by trying to do too much in a single-piece print, I created a design that required a lot of cleaning to get rid of support material to get in the way of good operation. So I set about creating a new design that incorporates steel hardware into the plastic truck to increase strength, weight, consistency, and easy rolling. The art of 3D printing has come a long way in the three years since I got my Creality Ender 3. With a growing number of users, materials have improved in quality, while the prices have remained relatively stable despite inflation. A roll of filament is still in the $18-25 range depending on quality, just as it was three years ago. I selected the Ender 3 at the time because I wanted a machine that had all the basics, but it was expandable and easily upgradable if I needed additional features. As a newbie, I didn't want to invest in bells and whistles that I didn't need, especially if I found that I really didn't like 3D printing. My machine cost under $200 at the time, and I've added a few upgrades along the way. The newest Ender 3 v3 SE has all the upgrades I added to my printer, plus more, and retails for under $300, but at the time of publishing, it can be found for under $200 from several sources. You could use a printing service like Shapeways, but honestly, if you do a lot of models, it's cheaper to own your own machine these days, and the learning curve is easier than I expected. If you run into issues, there are hundreds of YouTube videos made by 3D creators to help you make better prints. I have printed enough models both for my layout and for household use to more than pay for my printer investment. I even printed the tripod system that's holding my camera right now. Anyway, back to this design. The key to this design is the use of 3 16th inch steel rod as the axles, adding weight, strength, and consistency, and 5mm flat washers embedded in the side frames to act as axle bushings. The metal-on-metal contact is consistent and has a much lower coefficient of friction than my old plastic-on-plastic design. The metal parts are available at most hardware and most big box stores, and my 3D files are available for free on the internet. See the link. I recommend that you do not use a service like Shapeways for this because by the time you add the print cost to shipping, you'd be better off buying replacement trucks. But if you own a printer or know someone who does, these are a great option for less than $1 per truck. Let's start with the truck bolster. This piece has not changed at all from my previous design. The included dummy coupler roughly matches the coupler position of a standard Lionel Freight truck. Feel free to alter the design as needed to fit your personal installation. Just don't sell the design or copies of the truck. Print the bolster upside down to get a nice flat finish on the top surface, and use a porsive necessary for the diagonal wings. I'm printing with a raft to ensure good bed adhesion and a good flat top for the print. This is a test print to ensure good fit, function over form. I'll clean up the look on later parts. Next, the wheels. Again, I left this design unchanged from before, except that I increased the center hole diameter to 4.9 millimeters. My steel rod measures in at 4.73 millimeters, but the PLA expands slightly as it cools, shrinking the hole. I found that printing at 4.9 makes a nice tight fit on the rod. You may need to change this dimension depending on your particular printer and filament. Next, the side frames. This part is a new design, with the finished part allowing for a 5 millimeter flat washer to be embedded into it. I originally planned to print the piece with the washer embedded into the plastic, but I found that press fitting it in afterwards works just as well and it saves time. The side opposite the washers is flat and has no detail. We will print the truck details separately and then add them on later. In my previous design, I had the details printed on the side frame along with the bolster receiver. What I found is that if I printed the detail side up, the bolster receiver required support that I later had to clean out. If I printed with the receiver side up, it wiped out the details. With two pieces, I can print the detail and I don't need to clean the support out of the receiver pocket. Plus, I can change the truck details, roller bearing, standard bearing, etc. without changing the entire design. Again, this print is a proof of concept. I will alter the contour to match my side frame details later. When the side frames are finished, clean any extra material out of the pieces with a file. Be sure that the holes on the outside of the receivers are large enough that the axles will slide freely in them. Too big is better than too small. When the pieces are clean and smooth, add the washers and click them into place. Then add the side frame details and glue them into place with a gel type super glue. I clamp them into place and let them sit for 30 minutes or so. Again, this print is a proof of concept. Later versions will fit better on the axle receivers. When these are dry, attach one of the side frames to the truck bolster. These should snap into place. If necessary, you can add a drop of that gel type super glue, just to be sure. Now, let's put the wheels on the axle. The very center of 027 rails measures out to 33mm apart. So, to have the center of each of these wheels on the center of each rail, these wheels should be spaced about 28mm apart. There is some wiggle room with 027 track. Ideally, the wheels will fit snugly on the axles, but once again, a little gel super glue will hold them in place if necessary. Make sure the wheels are spaced evenly with equal amounts of axles showing on each side. Now the tricky part. Insert two completed axle assemblies into one side of the bolster and side frame assembly. Then, carefully line up the other bolster and push the parts together. This can be trickier than it sounds. And here's our completed test set of new trucks. Let's put them on a car. And here it is on the layout. Actually, this is a slightly upgraded version from the earlier part of the video. I'm still not completely satisfied with the appearance of the truck, so I will continue to tweak it and update the files on Thingiverse. The function, however, is much better than my previous all-plastic version. Again, feel free to edit this design to fit your needs, just please do not sell the design or sell physical copies. As an aside, I encountered an unprecedented number of technical difficulties in making this video. From camera glitches, to deleted files, to really strange printer malfunctions, and I was nearly unable to complete the project at all. So, I hope that nevertheless, you enjoyed this video such as it is, and I hope this provides a budget solution for finding replacement trucks and parts. Please like this video, subscribe to the channel, and share or comment about your budget solutions to the problem of finding replacement trucks. So, keep the trains running, and we'll catch you next time on Toy Train Tips and Tricks!