My brother and I both have a great interest in welding and fun dangerous stuff. So a few years ago when we got our first welder and we were just learning to weld, we thought it would be a fun and simple first project to make a small model sized pulse jet engine. That was simple and fun. We then thought what could we do next that would be something like this? Of course we thought bigger is better, especially if its remote controlled and thats what lead us to creating the Pulse Jet powered Ice Racer! Here is the final video of it running!
What is a pulse jet? Well, it is the easiest type of engine that you can make in just a matter of hours and they have no moving parts (the valveless type). They are extremely loud (140+ db) and glow red hot and can run on any type of fuel. Here is a link to a wiki page explaining more about them better than I can. Also, this is the design of the engine we used.
If your going to do this make sure you do it during the day and on a larger lake not in a city because these things are really fricken loud. Running pulse jets at night pisses off the neighbors as you can hear it from miles away...
Let me know if I should clear up some of the steps as it may be just a little confusing.
Here are my answers for the Make to Learn Youth Contest - Most answers regarding how to make it are already throughout the instructable
What did I make?: I made a remote control ice racer that uses a pulse jet to produce the thrust to move and remote control parts from an old RC car. I have a link above as to how a pulse jet works but basically if you have the correct dimensions it will stay lit and continue on its cycle, thus the name pulse jet as it has continuous explosions that create a distinct buzzing sound. The main tool that I used was a MIG welder to weld together the metal frame and pulse jet. I have been welding since I was 13 and I am currently 15.
How did I make it?: My brother and I got the idea from a project we did 5 or more years ago. That project was also an RC ice racer but much smaller and used a motor and propeller from an old plane. A few years ago when we got the welder and were thinking of project we decided to make pulse jets since they were simple enough. That then lead to bigger pulse jets, which then this year led to us making something that actually moves out of one. My brother and I worked on this project for 3 days. At the start we had a rough idea as to what we were going to do but most of our ideas changed as we progressed. Mostly just the design of the frame changed. The front steering was mostly just guess and check.
Where did you make it?: We made it in our garage workshop at home and took it to a near by lake to test it out. It connected with other activities in our lives because we had made the pulse jet a few months before so we finally put it to good use!
What did I learn?: The biggest challenge we faced was setting up the steering and servo. That just took some time and finess to get into the right spot and to make sure it all lined up. I am immensely proud of how the whole thing turned out! We weren't expecting much, but it was above and beyond what we expected. Plus, I am proud of how well this instructable did! If I did it again I think I would change the placement of the tank to the front area and have it sit upright and change the design of the frame and make it narrower to save excess weight. Also, if I had a lot of time, I would make a big pulse jet because the bigger the better! (and faster)
Step 1: Design
What took a long time, was we had to figure out where to stick the propane tank, as we wanted the pulse jet to run down the middle of the frame and we didn't want the tank to sit on the front and put a ton of weight on the control arm and front skate. Plus, we just wanted it to look as cool as it sounds!
Step 2: Materials and Tools
30+ feet of 1/2in x 11ga steel bars/strips
2 pairs of old skates
32in x 16in 20ga steel sheet metal
1/4in steel rod
Lock screw stoppers
Pulse Jet Materials:
Small 10-15 pound propane tank
Rubber grill hosing
Electronics (harvested from a old RC car):
MIG or TIG welder
Chop saw with metal cut off disc
Hand held grinder
The usual hand held tools
The total cost of everything was probably around $30, although we already had most of the materials besides the metal.
Step 3: Skates
One of the hardest things we had to do for this whole project was to get the damn blades off the actual skate.. Now cutting and grinding off the blade on the old skate was a piece of cake, but on the newer skate it was practically fused to the base of the boot with plastic.. We ended up having to basically melt that plastic and pry it out, making sure not to bend the blade.
Step 4: Welding and Cutting the Frame
Next for the frame, we created the middle X part for support. We did this by cutting two 28 inch pieces, welding one in place, and cutting the other piece in half to form the X (see photos 4 and 5).
The next step for the frame was to finish off the back skate mounts. This was accomplished by lining up and extending the bottom part of the X to line up with a 4 inch piece coming off of the base of the triangle. Once this was all welded together, the frame was complete (see photos 6 - 10).
Step 5: Mounting the back Skates
Step 6: Mounting the Pulse Jet and Propane Tank
For the propane tank we thought it would be best to mount it directly to the left of the pulse jet, leaving a few inches of space as the pulse jet gets extremely hot.We also had to mount the tank on its side otherwise we thought it might get to top heavy. Although, it probably wasn't the best idea to mount the tank on its side because it probably messed with the flow of the propane and pressure.
Step 7: The Front Skate
Step 8: Electronics and Propane Hose
Step 9: Finished and First Test!
More videos soon, but here is one of the test on pure ice that I posted on the first slide.
Hope you enjoyed it! Comment if you have any questions!