FINALLY DONE! 1970 Vespa 50s electrification project

- Slowly working on the controller/DCDC converter/ throttle compartment. Bought and installed nut inserts for fastening the controller with machine screws. As I want to be able to unscrew the controller and I will not have access to the two rear screws, I will make up two brackets for it to slide into in the rear, and just use screws in the front where I can access the screws with a ratchet.

- Charger came in. I landed on a Supower 8A version. I wanted to go bigger initially, but 15A's and up are so huge that it wouldn't fit where I plan to fit it. Now to find some neat solution to mount it inside the opposite (left) bubble in the chassis, both free from contamination and still let it breathe like it should.

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If you wrap some fiberglass cloth around the wood panel and soak it in gelcoat it will waterproof it perfectly without losing size or shape,it doesn't even have to be fiberglass cloth, you could use speaker cloth and use a paintbrush to staple in fiberglass resin to seal
 
I was going to laquer it inside out, and caulking all seams/joints so water doesnt get into the fibres through the cuts. I haven't been worried at all actually, good quality beech plywood with the correct surface treatment can last a long time in really rough conditions.
 
What I also thought of as an option, but forgot by the time I replied to your comments, is to plastidip the side of the plywood that will be exposed to water and dirt.
 
Once again, some tiny tiny progress going on in the basement :D

I found a solution for fixing the rear of the controller that I am very satisfied with. Two brackets with some sort of rubber protection is bent and positioned so one can slide controller into position with the use of some force, then it is secured by the two front screws like already shown. The rear brackets also make use of nut inserts on the back for some proper torquing down. I slid the controller in and out several times and I am confident this will last a long time because
A. The force needed was the same every time, i.e only flexing the brackets within it's elastic region
B. The two front screws were almost sufficient on their own

Also, I took pictures of the solution for fixing the cycle analyst. I had to drill a hole right next to where the steering lock was previously, for inserting an M5 captive nut. An M5 threaded rod is then screwed into the insert and torqued (and loctite'd) with a flange nut. This gave me a surprisingly stiff rod (ahem :roll: ) to simply slide the cycle analyst onto and secure width wise and rotation wise with a nut and serrated washer on each side.
The hole in the chassis, where a steering lock previously existed, will now conveniently be used for wiring.

Today, my very friendly brother will show up with a few meters of matching color wire and help me extend the wires properly, so they reach all the way back to where my connections will be.

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Swingarm design is done. I'm not sure if I will wait for the guys at the workshop to have time to do some machining for me, or if I will just send it all to a machine shop... I've generated 2D drawings for every single bit, so I could potentially just hand it over to someone and have it done by the end of next week or so.. Hmmm..

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Looking good!
Maybe consider using a bush on both sides of the axle that fits exactly inside of the rectangular box section of the swing arm. That way clamping/tightening the nuts won't cause the box section to deform. But maybe you were already planning that.
 
SlowCo said:
Looking good!
Maybe consider using a bush on both sides of the axle that fits exactly inside of the rectangular box section of the swing arm. That way clamping/tightening the nuts won't cause the box section to deform. But maybe you were already planning that.
Click to expand...

Yes I am :) (good thinking)

I will also have threaded steel bushings welded in where the screw for securing the motor torque arm goes, for strength and convenience. Notice how big the diameter of the hole is; the bushing will have a 12mm OD and an M6 thread
Aaand I will also have a hollow bushing without threads welded to the bigger diameter hole (for the brake torque arm) for a pin to slide through, and to be secured with snap rings and/or e-clips. This will be a lot stronger than having a pin twisting directly on the box section every time I hit the brake. Again, notice the size of the hole, it is 20mm to accept an OD20/ID16 bushing, so I can utilize a 16mm pin with turned grooves for clips (huge opening in the brake torque arm, for some reason).

I will include the bushings in the model and document them as well, then ship to a local machine shop for a quote. Hoping it won't ruin me, as it would be fantastic to simply receive a freshly powder coated swingarm in a week or two.
 
Nice project. Keep in mind that controllers need air flow for cooling, so plan on exchanging more air than just that the original slotted side. I'd vent the charger too. Also, include space for extra batteries in your initial plan, because you'll definitely want more batts once your up and running.
 
Slowly making the swingarm on my own. Things are still so busy at work that I can't spare any time going to the workshop for personal projects, but I managed to squeeze in an hour today.
"Control room" is also taking shape.

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I need help picking a new BMS.

I sent back the 80A version and finally got my money back. They have a 150A version available, but design wise it would be so nice to have one that is no larger than 65mm in one direction.
Advice is greatly appreciated!
 
I never found a more suitable BMS (sizewise) than the 150A version of the one I had, so I just went for that one. It's on its way now, which means I can finally continue on the battery box build.

Apart from that, I have been working a little on the swingarm, making all the sheet metal parts for it. When it was all made and I mocked it up, immediately saw that this thing needs some reinforcement.

So I've done a few things to stiffen the structure. First, I've shortened the distance from the motor axle back to the shock, making it 35mm shorter than what would be the identical measurement of an original Vespa motor. This will reduce bending moments on the (previously) very weak rear stay of the swingarm.
Second, I've closed the box structure by adding an upside down U-shaped piece of sheet metal, which will be riveted to the main part of the swingarm to create an as solid structure as possible.
Third; I need to decrease the sideways overhang of the shock mount. This is not only to reduce torsion on the swingarm, but I found that the mount would actually interfer with the motor the way I intended it to be.

So still some designing to do, some labor down the drain, but that's how it is when your finished product is also your prototype :)

Oh yeah, and I demagnetized the magnet on my electronic throttle in an attempt to changing the cable that came with it (it was soldered). So now I have to find beg the seller for a replacement magnet and find a way to replace it.

No pictures to show, really...
 
Okey one picture, from some trial fitting yesterday. There was a set of screws which had their heads sticking out so much that I needed that green spacer between the brake bracket and the swingarm, but I drilled the through holes in the bracket so it would accept the same type of screws that hold the brake disc, so now I have the swingarm much closer to the brake torque arm, to greatly reduce the bending moments from the pin that takes up the braking forces.

Picture from before the modification. The fact that I didn't even have enough threads for the torque arm (thick little piece of sheet metal) for the motor axle was also an important reason why I had to change the screws :D

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cool project!
how's it going?

I am learning so much from you.
Planning to built one soon.

Thank you.
 
Wow, has it been 1 year and 4 months already..
Actually I haven't gotten much further. I have tested the battery pack on a huge power supply at my brothers workplace. The batteries did fine, but the BMS popped a FET.
I have also been at a standstill on the mechanical side, simply due to life catching up on me.
I have ambitions of starting up on the scooter again now. I need to find a new solution for shock mounts, both upper and lower.

Then it's wiring, making a box for the battery, and we should pretty much be there.
 
Actually, when I look at my last update I see that I have actually made some progress since that. I'll get some pictures up when I'm near a computer!
 
Alright, this is where I am at right now:

- I had my battery pack tested at my brothers' works' lab, where it performed like expected: I was warned that my cells are not fit for any high currents, maybe not even at their rated cont. Amps (10A per cell). What we saw was that at 70A/4000W, they were doing just fine. We had buildups to 40 degrees C somewhere inside the battery pack after 10 minutes of steady "running", but it stopped rising further. No significant voltage drop either. At 100A (supposedly 6000W) on the other hand, the heat was building up to over 60 degrees inside the battery pack within a few minutes. The voltage drop was also significant, which tells me the cells were not having a great time. A resistor blew up on the BMS too, which is another story (and a different thread actually). Conclusion wise, I will restrict the amperage on the scooter quite heavily to begin with, and definitely keep a thermistor deep inside the battery pack, to be kept an eye on via the CycleAnalyst.

- I am finally about to send the swingarm in for final welding. I didn't risk keeping the original shock mount, for stiffness purposes, and the fact that I needed to find a new shock mount both on the swingarm and inside the frame, combined with little time at hand has put the progress to a standstill for some time.

I don't have too many pictures either, but I'll post what I have :)
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Great progress!
I do hope you will drill the hole to mount the rear shock on the swing arm at least 10 mm higher than the black dot. Otherwise it seems the shock will be solidly mounted to the swing arm without the possibility to rotate around the bolt hole. And to get a better angle for the shock maybe move the hole a few centimeters to the rear. Otherwise you'll have a falling spring rate when compressing.
Good luck finishing the build!

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Thanks,
The hole will either be where the mark is, and the bracket on the shock remade, or the hole will be higher up, like you say, to accommodate the current bracket. The latter will bring on some issues with the bearing cup being too large of a diameter to fit through the 40mm square profile without having to start chewing on the top section of it.

There's not enough room further back, unfortunately.
 
Hi,

how did you determine the material and thickness requirement for your swing arm? What steel and thickness did you use?
I'm building one right now, and I think I'm building a tank. :oops:
I honest to god started with a 10mm thick 80mm wide flat section of steel.

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If I don't fsck-up the welding I can use square tube for the arms for sure.
 
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