DIY (Mini) ebike/moped -> square tube frame, hoverboard motors - does this look reasonable? Any obvious oversights?

Dont have any black filament, which i wanted for the mount and the store was out when i visited on friday, so it will get sprayed eventually.
Which plastic is it made from? I'm not sure what solvents PLA is sensitive to, but ABS and other styrenes work great with Krylon paints using Xylene; they bond very well with the surface when applied correctly. (just don't slather it on or the excess wet solvents may melt the surface of the plastic).

Rustoleum paints suck ;), which is why they're usually cheaper---they have less pigment in them so it takes more paint and end up costing about the same per surface area as just doing it with Krylon. ;)

Havne't found a store brand or other cheap paint that is much more than just a bit of solvent and almost no pigment.
 
PLA isnt soluble by most common solvents as it isnt oil based and ive used the cheap chain store brand spray paint on it before with no issues.

Got neither krylon or rustoleum around here.
 
You're not mucking around, constant progress.

The prints look great. Are they first iterations? What kind of measuring tools do you use to acquire accurate dimensions?

Are you going to powder coat the frame?
 
You're not mucking around, constant progress.
Thanks :)

The prints look great. Are they first iterations? What kind of measuring tools do you use to acquire accurate dimensions?
With the phone holder i already knew the measurements required for fitting onto the frame, 155mm between the tubes, 25mm for the tubes themselves, do that in my design, i use blender because im no good with cad, and it fit first try.

For the holes into which the phone slots i just calipered the outside dimensions of my phone-in-case-folded-open, subtracted a MM from each since the case is pleather and a bit compressible for a secure fit.

For the v-brake posts fender mount i calipered the cylinders onto which it was to slide and measured the distance between them with a ruler, did a basic mockup which was printed 1mm thick for a test fit.
Found i needed to spread the holes by 1mm or so, did that, designed the rest, printed it and found the spacing was right.

But the smaller diameter of the holes, the brake mount posts have a step of about 1mm larger towards where they attach to the frame, this was the area my test printed mockup fitted, was just a fraction too small, fixed by running a right size drill bit through to widen it by those fractions of a MM.

I1vD3Ji.png


The rest of the fender, its two sides parts and the central rib fitted together and into the v-post-mount first try, they were all designed together, their screw holes booleaned/cut by the same 3d models and their fit against each other designed in with some tolerance added in from experience with putting together 3d printed things.

Another example of printing experience coming into play was the rear light, aiming for strength where needed and designing away having to use a lot of supports, those two are often the same thing as prints are quite strong in x/y and weak in z, relative to the print bed.
The L shaped top part slots inside the other part, its held in by the panel mount style diodes, and forms a clamp which holds to the rear frame rail and is also locked in by the saddle as it is bolted down through it.
The L was printed on its side so all layer lines go through the whole L, and the lower part was printed with the side facing us downwards for the best surface finish on the visible side, supports were required for the overhang closest to the L part and the half circular cutout but the inside was bridged alright by my creality hi, just needed minimal cleanup in there with some tweezers.
0LGhKQv.png


Are you going to powder coat the frame?
Dont have the hardware or will to spend for that, im going with spray paint as im not all that fussed a completely polished look. The bare metal is getting matt, or maybe satin, black.
The fender mounts may also be getting black, or possibly silver for a bit of contrast.
The front/rear lights will be silver.
 
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Black and silver are a sure thing. You're not tempted by sparkly paints? Luminescent is the type I'm most curious about.

I have no experience with powder coating, but a professional frame builder friend insists on it for some reason(s). It is expensive, and a limited colour palette.

The details of your rear light are interesting. I hack everything together with aluminium and rivets. 3D printing is an eye-opener. No grinding, drilling, bending, or bashing. I see the appeal. Especially because you can work in the evenings without loud tools being a nuisance to others.
 
Not sure if you need tips on painting, but if that's going to be a usual 1K rattle can paint, I'd recommend a good epoxy primer first. That should really improve corrosion resistance.
The idea i have is to strip the frame, spray it down/wipe it off with brake clean, let dry, apply a primer, then color on top.

Never really done any painting of metal but figure clean and primed is a good base, thats what i do when painting miniatures and what ive seen people do in vids.
 
The idea i have is to strip the frame, spray it down/wipe it off with brake clean, let dry, apply a primer, then color on top.

Never really done any painting of metal but figure clean and primed is a good base, thats what i do when painting miniatures and what ive seen people do in vids.
Surface prep is indeed everything. Brake cleaner is super aggressive but I guess you have raw material.

There's two kinds of primers you'll encounter for this purpose - etch and epoxy. I'd go with epoxy.

For the paint, ideally you'd apply color and then clear coat on top. Dedicated 2K clearcoats are much more durable than all-in-one satin/gloss paint.
 
Still need to design the frame mounts to hold it by the two tabby things in the middle, but the rear fender itself isfully printed and put together:
sPh6G2U.jpeg


Did a test fit and noticed that profile of the rear tire differs quite a bit from the front since the rear rim is considerably thinner, also, im going to need to make cutout for the chain:
0zKZXO1.jpeg


I could redesign it to be printed thinner but i dont feel like it would be worth it in time and filament required and having both front and back fenders the same width makes sense to me.
 
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rapid progression
I really feel im more like slowly creeping at the moment, not feeling the urge to 3d model but it will come back :p

Anyways, today i rode the min-ebike to work.
Dont have to actually have work before tomorrow.
So if the batteries had run out or i had a breakdown of some kind, it wouldnt have mattered more than me having to ride the buss a bit, then drive to collect it from the breakdown.

It went well and the battery meter still showed 2 of 5 pips after 20km, i went on a little detour on the way there.

So how did i get home?

I operate construction machinery and tomorrow ive got an assignment 35 minutes from the garage i work out off, or 10 minutes from my own door, so i drove a telehandler home.

Ive received that 2nd charger i mentioned so both batteries are being charged at work, to be ready to power me home after work tomorrow.
 
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