DiY Cherry Stick | Trampa Infinity Trucks | 8" Slickline Wheels | Ollin VESCs | Dual SK3 6374 149 KV | Scramboard Motor Mounts and Pulleys

@bill_f I like how you used a modified half lap/mortise and tenon design. It looks strong, but the top looks very clean and shows off that woodgrain. I’d love to see a version with figured maple piece in the center!

Some wiring questions here and a short update. Should be getting a pair of VESCs from diyelectricskateboard tomorrow. I also ordered a pair from Ollin with heat sinks. Been told they will arrive soon. Might wait for those in order to have heat sinks and use the others as backups or on my next build. Damn these things are hard to get! Sanded off the crappy laquer that I had put on before. Could never get it smooth even after thinning and a few tries. Went with some some spray-on instead. Did about four coats. Looks a lot better, imo. Got some grip tape. Trying to figure out a cool pattern that works with the battery box placement which will be on top, between feet.

Had to drill out some holes on the Scramboard motor mounts in order to get them to fit on the SK3s. Luckily, I was able to use the motor mount that came with the SK3s to align the other two holes. For some reason, the Scramboard mounts have two holes in the right place for the SK3 hole pattern (but not four??) You can see the undrilled mount on the left. I countersank the holes to keep things flush and away from the motors.

Will start with a 12 tooth motor pulley (had to order one to work with the 8mm shaft on the SK3. The Scramboard kit comes with pulleys bored for 10mm shaft.) Was also able to order a 15 tooth motor pulley which I’ll try later. The 12 tooth gives me a 1:6 ratio which, with a low KV motor (149) might be too slow. ?? I had to order some longer belts to use with the 15 tooth pulley http://www.aliexpress.com/snapshot/7823362372.html since the belt tensioner slots on the motor mounts were maxed out already on 12 toofs. Can’t find pulleys with 8mm bores that look like the ones that came with the Scramboard kit (right pulley, below pic). These have the set screw on the side, providing more purchase on the axle. The ones I’ll be using are off the axle end by about 3.5 mm. I think they’ll work okay though. If anyone knows where to get a 12, 14, or 15 tooth motor pulley that looks like the one in the image below and has an 8mm bore, please tell.

Now for some wiring questions. Please let me know which diagram looks correct. I kind of feel like the first one is wrong. Need to wire between VESCs differently, like in second diagram. That’s my guess. Electronics is not my strength by any means. Once I get this simple version up and running, will look at adding two more batteries to create 10s2P rig. Will then look at how to make battery charging easy. Haven’t even begun to figure out how to set up this coulometer. One of the eMTB guys here has it on his rig (forgot who).

Version 1: You can edit or comment on doc here.

Version two: You can edit or comment on doc here.

Thanks for your feedback! Great community here.

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Just some minor thing: Ground is not -37v but 0V. Otherwise you would have a total voltage range of 74V.

Also diagram 1 should be the correct one. You don’t want to connect the vescs in series but parallel.

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Okay, thanks for your help. Good to know.

Sweet lookin’ deck!! =D

Finished Build Recently

Still need to do a few more things like add the coulometer once I figure out how and where to put it (space limitation on battery box). Might 3D print a custom enclosure for it and place it on top of the UK Battery box. Been running it at 10S, (2X 5000mah 40C batteries) and it’s definitely torquey with the 149KV SK3s. Goes up hills no problem (180 lbs rider). Hit 19.7 mph on a 7% hill (going up) with full accelerator. Still need to do calculations on flats and downhill although feel more comfortable testing speed going uphill since stopping is faster. Brakes feel great. Nice and progressive and predictable. Remote feels great, nice and responsive (GT2B). Happy with the gearing for now. I can feel there’s still plenty of power under the hood if I ever want to gear down. Could also go 12S.

Vescs, batteries and motors are all staying cool, even on hot summer day. Was worried about VESCs. (Using diyelectric’s for now since they arrived first. Was hoping to get the Ollin’s first since I ordered them with heat sinks but it doesn’t look like heating is a problem so I went ahead and installed the DiYs.) (Still waiting for the Ollins.:stuck_out_tongue_winking_eye:)

For now, just using the two 5000mah batteries and getting about 1.55 Volt dropage per mile with hills (6-12%). With four batteries, in this type of terrain, I would expect about 20 kms range. Thinking I might just keep two batteries in backpack when I ride and then switching out when needed. Want to avoid more wiring (for parallel) in battery box since it will be getting tight in there. Will figure that out later.

Enough words. Some pics:

Would look nice with some aluminum hubs.:grin:

Will post some ride videos once I charge up the GoPro.

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That deck is so beautiful and deserves something more beautiful than these yellow boxes. You are a serious craftsman and I’m sure you will find/make something what fits the Cherry Stick better! Respect to your wood working skills btw. Does it have any flex?

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Superb workmanship, there truly are some bloody clever people on this forum/in the world! :smiley:

Well, in the first moment i thought about honey combs (grip tape) and therefore the yellow boxes are matching. In the second moment i thought about the name “Cherry Stick”. He should uses red boxes ^^

really this is ART!

LOVE IT!.. seeing things like this makes me so happy to be involved with this community.

Ditch the yellow boxes…

You might also consider can bus for the VESC, however splitting the PPM is perfectly fine too

Beautiful job! Love the whole build. I do agree that this deck deserves some equally beautiful wood boxes to continue the wood theme though. Maybe some custom finger jointed boxes, or something like that, since you obviously possess the skills and equipment. And maybe wrap the motors in some wood veneer, if you wanted to get ridiculous.

Hi. Thanks for comment. It does not have much flex. You can get it to spring up a little if you want to make yourself light going over bumps, cracks… The yellow boxes might get changed to something more custom later when I get this vacuum forming machine. Could create a custom VESC enclosure as well. Lots of possibilities there. Slim batteries on bottom would be nice too, leaving topside nice and clean. I can see myself going down the rabbit hole on this one, ha ha.

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Thanks man. Coming from you this means a lot! Couldn’t have gotten it running without this forum, so thanks for setting it up and hosting it. Been really enjoying your VLOG and watching the evolution and growth of your business. Running a small business and trying to grow it is no joke! I really like your marketing approach which I think is one of the most important factors in the success of a small business. (Had some (limited) experience with that.)

The verdict is in: The yellow boxes are not getting much love. ha ha. Off to the vacuum former when it arrives.

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Okay, finally got a GoPro on a stick. Just a quick video from a spin up and down the block. The more I ride it, the more I like it.

https://www.youtube.com/watch?v=hwhWyyPCI84

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Hi. Board has been running great for most part but am getting an oscillation in right wheel as I speed up. I think it has to do with one motor becoming weaker than the other at lower rpms. Left motor is easier to stop by hand when at lower rpms. At higher rpms, seems to be fine. Right motor is hard to stop by hand at any rpm. The video below shows this. VESCs have not been changed since initial setup. They both have exact same settings. Any ideas? Do you think it’s a motor issue or VESC issue? Or something else. Thanks in advance.

https://youtu.be/k2Z31dxptdg

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Did you get the chance to measure the energy use for this nice ‘‘beast’’ ? :slight_smile:

You said you partly chose ‘‘city wheels’’ for this use… has it payed off? :slight_smile:

I’ve measured the energy consumption but haven’t hooked it up to a watt meter to see what it’s drawing. With 10 Ah, 10S, I’m getting about 14 kilometers. I have the LVC on the VESC set at 3.2 volts/cell. I carry a couple spare batteries which doubles my range. I like the Innova inline tires since I believe they have lower rolling resistance than other knobby tires. I haven’t inflated them as much as I can though. Haven’t compared them to other tires on this board, but for city riding, they work great. Riding on pneumatics is so nice. Gives you better feel of the board as it’s not vibrating so much under your feet. This is especially useful if you’re not using bindings.

Oh I see… well from figures you gave (36v nominal) x 10 ah = about 360wh maximum, where I should probably take off 5-10%, so 360-(36/18) = 324wh / 342wh. (not sure of actual available battery capacity you got - had the chance to use)

Which would yield around 23.14 h/km - 24.43 Wh

Not sure precisely but it looks to be over 20wh anyways… I assume if you got hills then these do eat up energy + maybe the speed is also higher than 15kph :slight_smile:

Nice riding then, I hope u still get to ride it in between building your fanstastic 2 wheeler board you are planning to make :wink:

Took a while but finally managed to put together a video of rides around town.

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hi nice video