Wooden box II build

[thoxbui]

The quest for more battery space continues!
Started with this, a "Cruizer Lightning" with a pretty anemic 24v of NiMH, brushed motor.

Cut out seat tube, mount the seat against the frame, new handle bar

Built the box out of wood

I'll be using 48V8Ah of sub C NiMH (for now) with a 1000W controller.

Tho

 

[thewmatusmoloki]

Hey Thoxbui,

Super-Cool looking mods to that bike so far. 8)

I love the mods that make a big diff, without much cost.

Keep up the awesome work.

Matt.

 

[AussieJester]

Will you be using the battery box as structural support for the frame? If not i think your going to have issues with frame flex/breaking when you pile the weight into it. A curved seat tube would be the shot IMO...

Best of luck, liking the shape of the battery box too...

KiM

 

[thoxbui]

Will you be using the battery box as structural support for the frame? If not i think your going to have issues with frame flex/breaking when you pile the weight into it. A curved seat tube would be the shot IMO...
Best of luck, liking the shape of the battery box too...
KiM

I hope it'll be fine. I rode for years on a bike with no seat tube and had no problem. I figure with the box resisting the compressive load from the top, I'd do fine. My main fear is that I had to drill one hole in the down tube for mounting Riv-nuts, and that may reduce its ability to resist the torsional load against fatigue failure. But since there won't be that much pedaling, that may not be a severe issue.

 

[AussieJester]

I hope it'll be fine. I rode for years on a bike with no seat tube and had no problem.

And that was piled with batteries and an electric motor? I hope for your sake it will be fine too...
The torque of the hub motor is going to have fun with the unsupported chainstays though i believe...

All the best

KiM

 

[torker]

This is cool to see. I had that very bike/sold it. Are you gonna throw 48 v at that brushed motor? It might get a little warm. Maybe ok if you keep the amps low..

 

[thoxbui]

This is cool to see. I had that very bike/sold it. Are you gonna throw 48 v at that brushed motor? It might get a little warm. Maybe ok if you keep the amps low..

It seems to be ok at 48v continuous. This is my second lightning cruizer. My first one was rather crude (it was my entry to the ebike world about 5 years ago)
But to Aussiejester's point, I do plan to have more batteries than these 40D's so I hope that I'll survive it.

 

[nicobie]

I would seriously think about Kim's suggestion and add a curved seat post.

 

[etard]

Even a curved piece of wood could be enough. I like your new box alot! What kind of wood is that? Very cool.

 

[thoxbui]

Even a curved piece of wood could be enough. I like your new box alot! What kind of wood is that? Very cool.

Baltic birch veneer ply, coated with shellac:
http://thoxbui.com/electricbikes/slides/IMG_1482.html
Tho

 

[etard]

Nice page Doood!! You are truly the Clampmaster!!! Keep up the good work, look forward to see how you progress. 8)

 

[cargo]

.

 

[zap]

I like your box. One can never have enough clamps when doing things like that.

The Baltic plywood is nice to work with eh? I built a recumbent out of it that I rode till I cracked the rear triangle connection point going too fast over too tall a curb.
I used Baltic for the box on my pusher and even though I would have liked it to be lighter weight, I think it came out OK. Wood always has that 'mmmm' look.

If the the riv-nuts allow too much flex you could always through bolt. Gluing the sides like you did will add a ton of solidity.

Nice work.

 

[torker]

Dang! That is a lot of clamps. So are you putting 48 v to that little ole' 24 v controller? I can see now I should have kept my Lightning Cruiser!
So much fun I missed modding the snot out of it. Well, I bought it for fifty and sold it for 200 so maybe I can buy it back in a year for fifty again when they kill the batteries.. I just put some sla on it to get it going. Never overvolted it

 

[thoxbui]

Dang! That is a lot of clamps. So are you putting 48 v to that little ole' 24 v controller? I can see now I should have kept my Lightning Cruiser!
So much fun I missed modding the snot out of it. Well, I bought it for fifty and sold it for 200 so maybe I can buy it back in a year for fifty again when they kill the batteries.. I just put some sla on it to get it going. Never overvolted it

No, I pitched the original controllers. I do my best to match the controller to the voltage that I aim for, so I bought one from tncscooters store (20-30 bucks). It's a brushed motor, so it tolerates a lot of weird things. For a while, the "controller" was an on-off toggle switch. Great sparkly fun at 48 volts.

 

[AussieJester]

heheeh@ the clamps thats awesome ...


KiM

EDIT: just showed your altered frame to a boilermaker/welder (over 20 years experience) mate of mine, he also agrees your going to have issues with frame flex/breakage...

 

[thoxbui]

heheeh@ the clamps thats awesome ...
KiM
EDIT: just showed your altered frame to a boilermaker/welder (over 20 years experience) mate of mine, he also agrees your going to have issues with frame flex/breakage...

As I often said: you can't be rich enough, thin enough, or have enough clamps!

I'll see your boilermaker, and raise him my PhD in metallurgy!
But seriously, I didn't do any analysis AT ALL when I do these kind of things. What's the sport in that? It does look kinda skimpy, but I do have past experience to give a little bit of confidence that it _might_ work.

Will report back when I get the thang runnin'.
TB

 

[amberwolf]

Did you actually throw away the original controller(s) or do you have them in a drawer someplace? If you've got them laying around but won't use them, maybe I could trade you something for them?

Regarding the frame, if you do need a reinforcement, it might look nifty if you do it like this, one on each side:

You could use chainstays or seatstays from an old ten speed, and they'd be strong and light, and likely serve the purpose just fine.

 

[thoxbui]

Did you actually throw away the original controller(s) or do you have them in a drawer someplace? If you've got them laying around but won't use them, maybe I could trade you something for them?
Regarding the frame, if you do need a reinforcement, it might look nifty if you do it like this, one on each side:

You could use chainstays or seatstays from an old ten speed, and they'd be strong and light, and likely serve the purpose just fine.

Sorry, I think I threw it out. I have a max amount of "stuff" I'm allowed to keep in the house, so I have to move them out quickly. I'm not even sure if it works.

Yes, I can reinforce the frame. But I hate using my welders, I rather make sawdust

Tho

 

[rgody]

Kim :

Your ebike design remember me the bicycles from http://www.ellsworthride.com/

Nice to mix carpentry and ebikes !
Keep doing good work.

Rodrigo
Viña del Mar
Chile
www.movielectric.cl

 

[AussieJester]

Yup... and look at the size difference in tubing used in both downtubes chains stays and seat stays
on that bike compared to the OPs old classic cantilever framed bike...

KiM

 

[Toorbough ULL-Zeveigh]

also that's a solid load bearing rear fender.
not just sheet metal.

 

[ryan_lirui]

The bottom part of the frame looks like ass. Shouldn't it look something more like this?

 

[thoxbui]

Thanks for all the comments guys. But don't worry that I'd get myself killed.
To keep things in perspective: you guys do know that I have modified and rode the exact same bike with the exact same power before, right? I rode it for a couple of years, and it was still fine before I tossed it into the recycling bin.
http://thoxbui.com/electricbikes/slides/Copy%20of%20cruizerinprogress03.html
Note that there was no seat tube either, and that's 40 D size Tenergy cells hanging on the frame. No SLA, but it ain't featherweight either.

The exception on this one is that I'll have an additional 10 or so pounds of battery. I can go into the logic behind why I think the seat tube may not be necessary in this case, but as I have not carefully calculated the stresses involved, there is always the risk of the extra weight become the straw that breaks the camel's back... but I doubt it.

And yes, I can design and build a brazed/welded structure:
http://thoxbui.com/home/sitebuildercontent/sitebuilderpictures/tandem.jpg
http://picasaweb.google.com/cyclewhitney/2009TempeTourDeFatBikeBQue#5391086579314977170
http://thoxbui.com/home/sitebuildercontent/sitebuilderpictures/bikefolding.jpg

Tho

 

[thoxbui]

Working on the batteries. I have 80 sub C NiMH; combined they provide near 8 Ah of 48 Volt nominal. Shown is one of the two 48V pack. Each is made of 40 cells. To control the charging, I use a thermal switch. I borrowed that idea from one of the threads in this forum.

My springer fork arrived in the mail today. It'll be interesting trying to figure out how to mount brakes on the fork.

Start to set up the practical stuff: rack, basket, large-thingie-carrier. Both the basket and the LTC are just office hardware that you can pick up at Officemax.