#1 I tried making a single-pipe cart without welding or large machinery (Name: Tanjiro Kamado)
The header image, which is full of domestic life, shows the single-pipe cart I created this time. I used a battery and an in-wheel motor for power.
A feature of this project is that I created a steel vehicle using only items available for sale, without any welding, lathes, or similar processes.
To build it without welding, I used bolts and joints for single pipes at the connection points.
The reason I built it without welding is because I don't know how to weld (^^;
Performance
As for the performance... honestly, I have no idea.
(^^;
That's because I'm a guy living in a tiny apartment with no license and no popularity, so the only space I have to run it freely is about 1 meter in my 6-tatami mat room (^^;
That said, what I learned from running it for 1 meter is that it seems like it will run at a decent speed and is quite sturdy.
Regarding speed, the motor I used is a 350W one (linked below), so by calculation, the total weight of the rider and the cart is about 95 kg (me: 75 kg, machine: 20 kg). Even so, it starts moving firmly, and the initial acceleration is surprisingly fast (though that might be because it's indoors).
Calculating the maximum speed here, from P=Fv,
v = 350/95 = 3.68 (m/s) = 13.3 (km/h)
That's 13 km/h.
The calculation gives the impression that it will run at a pretty interesting speed, but if you look at the link mentioned above, it's a very "suspicious" product, so I don't think it can actually run that fast.
Also, regarding sturdiness, the steel pipes used at construction sites, as well as the joints and bolts, shouldn't break just from one person riding it, so it doesn't budge when I get on.
(I wrote that, but in reality, the fixing force of one important joint was weak, and it popped out a few times. So I tightened that one especially hard. Maybe some unexpected load was applied. I initially thought it might be a defective part, but in any case, it's not the intended use, and it showed normal holding power once tightened firmly, so I couldn't tell if it was a defect or not.)
The joints I used are the NTY cross-brace joints shown below. I considered clamps and such at first, but I chose these for their appearance and functionality.
(By the way, the one that popped out was the last one)
Material Costs
Next, regarding material costs, the motor was actually a gift, so it cost 0 yen. So, my own material costs for the remaining battery, pipes, joints, etc., were about 37,000 yen. Expensive!
(*^_^*)
That's because three batteries cost 11,000 yen, and three casters cost 9,000 yen, which is already 20,000 yen right there. So, if you already have three batteries, you can build it for 37,000 yen, and if you also have 5 meters of steel pipe, which costs about 4,000 yen, you can build it for about 33,000 yen.
Still expensive!! But if you have the mindset of buying some nice clothes, the motivation, and "an environment where you can use lots of tools and make noise," it's not impossible to build.
However, tools are expensive!!!!
This was my first independent project, and since I didn't own an impact driver, a vise, or anything, it cost about 22,000 yen to buy the necessary tools. I think I did this with the bare minimum of tools.
The tools I purchased are:
・Impact driver (corded)
・Pipe cutter
・Vise
・Drill bits (M3, M8, step drill)
・Adjustable wrench
・Metal saw (unnecessary)
Everything except the pipe cutter was purchased at a home improvement store.
I used a Kyocera impact driver (linked below). As for how it felt to use, I thought, 'Since it's not battery-powered, I can use it forever!' but when I tried to drill holes in the iron pipe, it became so hot I couldn't touch it, so I had to use it in short bursts. However, that was the only downside; I was able to drill M8 holes securely, and I think its performance was more than sufficient.
At first, I thought about buying a battery-powered HIKOKI one, but it was ridiculously expensive and I was worried about whether it could actually drill through metal, so I stopped.
The best item I purchased was the pipe cutter, and the most useless one was the saw.
For some reason, I thought I'd try cutting the pipe with a saw at first, so I bought one, but it took about 40 minutes to cut a 7/8-inch pipe, and I haven't used it since.
The pipe cutter I bought immediately afterward (linked below) was a great tool that was quiet, cut quickly, and was safe, so if there is anyone who wants to cut iron pipes, I highly recommend it. It's also relatively cheap.
Production scene (one photo and a story of hardship)
I don't have any good-looking photos, but here is a photo taken just before completion, before assembly ↓
Looking at the photo, you can see at least 7 bolts driven in, and I drilled 16 other holes besides those.
Overall, drilling the holes was just really tough.
As mentioned earlier, there's the issue of the driver getting hot, but it was just so loud and my hands hurt!!
Plus, the precision is poor (that's my fault).
When drilling with an impact driver, it's just 'noisy' when the bit is spinning smoothly, but if it catches even a little, the impact sound resonates through the metal pipe, creating a 'Gagagaga!' sound that is definitely at a volume you shouldn't be making in an apartment. That was the most troublesome part.
On top of that, I had to keep pushing the impact driver with quite a bit of force the whole time, so the base of my right thumb really hurt.
Also, the whole cart is heavy and hard to move, and if my hand slipped even a little, it would immediately scratch the floor, which would scratch my fragile heart. Oh my.
So, it's better to do it outside as much as possible when building it.
As an aside, if you have money to spare, I highly recommend using a bench drill instead of an impact driver to drill the holes, as it's fairly quiet, much easier, and allows for accurate work.
It's hindsight, but I wish I had done that too.
The thing is, drilling a hole through a single pipe with an impact drill bit is difficult in terms of tools, precision, and technique. Bench drills are expensive, though.
Finally
It was tough in many ways, I made two big scratches and many small ones, and there are some wobbly parts due to precision issues, but when I assembled everything and finished it, I was super moved. The production period was about three weeks, and I spent quite a bit of money, so I was relieved that it actually ran.
Someday I want to run this guy on a big road!! That is my current wish.
Regarding the naming, I wanted it to be a name that conveys that it was made using single pipes, with the hope that it would become a strong and sturdy cart that could even carry a demon on its back, which led to the title 'Kamado Tanjiro'.
P.S. I haven't seen the movie yet