New Hummie Hubs!

Hi Bro, hope your good. Just a thought, will taking the 10mm cause more chance of wheel bit on decks? I remember seeing your wood carbon decks just about having enough clearance for no wheel bite.

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For your kickstarter :jack_o_lantern:

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I was thinking, how are you modifying? Drilling the hubs to accommodate the unthreaded portion and making new axles right? The surface finish of the axle is really important to prevent fatigue failure in the future, a rough surface acts as a seed for the cracks to start forming

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Absolutely sick build. Once youā€™ve had a bit more time with this beast, would love to hear your thoughts on range with the a123ā€™s on 15s2p. I have a butt tonne of those cells and was not sure if it was worth doing an Esk8 build with em, or just make a massive bike battery. If you already have a build thread, I apologize for getting off topic. @Hummie your contribution to this community is epic. Iā€™m gonna save all winter and hopefully Iā€™ll have enough to buy your drives and a deck. So freaking nice.

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Not moving the motors so no increase wheelbite

. The axle will be left largely as is and smooth. U think bare 20mm then 10mm thread or 15 n 15? I was told ten was more than enough threading. And then leaves lots of the bare smooth 12mm axle.

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looks like a very solid copper string :heart_eyes:

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Following up. I did:

  • riptide bushings Krank 93a Cone/Canon front, Canon/Magnum rear. I have my balls back :slight_smile: Thanks @Alphamail
  • ackmaniac firmware installed
  • wire loom for phase wires
  • charge port added lol, and missing screw fixed
  • switched to mini remote (the master cho gt2b is for testing stuff)

Gave it a test run, full charge, which for my NOS (new but sitting on sellerā€™s shelves for a few years) A123 M1 (2300mah) variant is 52v. About 1 mile down the road and 1 mile back, mostly full throttle (fresh paved yay!). 60/-50 30/-12 one way, 80/-50 40/-12 the other. Finished at 50v, sagged to 45v min.

30mph max. Sigh all my boards are about 29mph max at full charge. I was hoping 15s would get me to 35mph. Maybe the bearings will break inā€¦

Did about 30wh/mile. This will be a bit on the high side I think, as it was full throttle most of the way, and a bit windy. Still, I get 20wh/mile on other setups, so this thing drinks electrons. It should get worse I think when I eventually get to 100a motor 50a battery.

Screenshot_20181023-141352

The ride is plush, but you definitely feel the pebbles and cracks more than 97mm wheels. Itā€™s weird. Very plush, then big bump for small cracks, but still plush.

The double drop and the small wheelsā€¦ It almost feels like Iā€™m stepping down when I get on this board. :slight_smile:

Brakes still need to be dialed. Itā€™s a bit soft at max speed at -12 batt. Iā€™ll push it up gradually to probably -20. At slow speeds (going down a steep hill at walking speed), thereā€™s an abrupt transition from not quite enough brakes to almost lockup. I reduced motor min from -60 to -50. Will keep tuning.

I did have one glitch, testing high speed full brake to full throttle. I lost thrust for a brief moment, maybe 1 second. I think ABS over current and things like that get a reboot, which takes 3 seconds? So some other glitch. Kind of felt like cogging. No errors logged. Didnā€™t want to try to reproduce it (yet), as Iā€™m running 50v+, and long battery wires.

Oh, focbox remained cool, and motors were warm but not hot.

@Lionpuncher the range will not be excellent. 3.3v * 2.3ah * 30 = 228wh nominal. I usually canā€™t get anything out of the bottom 20-30%, so call it 182wh at 30wh/mile, thatā€™s 6 miles! If I get 20wh/mile in more normal riding, 9 miles. If range/weight/size/price is okay for you, the cells are really spanky. They can take a lot of abuse for voltage (Iā€™ve discharged my first pack to 2v for the whole pack, and it revived no problem. You can overcharge to 4.2v/cell, and they wonā€™t like it but theyā€™ll take it), and can handle cold weather pretty well. And they can be abused for regen current. I think 10C (23a or 25a if you have the M2 variant) was tested okay in the RC forums. Cycle life is great, 1000 cycles easy if you donā€™t abuse.

Need to add some kind of bumper for the rear truck. I think it rests on the tip of the baseplate when I lean it against the wall.

Thanks @Hummie :slight_smile:

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Nice to hear

I think the motors suck a lot of amps accelerating but on a smooth consistent 25 to 30mph will have to see the current draw and would like to see better efficiency than w a pulley with that

So weā€™re waiting for me to use this new tool to ream the hubs for the true 12mm axles. This week!!! Today really. Small steps waiting for expert advice and tools to show sorry guys this is how it had to go. But all n all ā€¦for the best. Not much work to do really in terms of hours at this point. I had them all done but then last minute with the bent axle realized this change in design is key and even with the mild steel axle (the manu fucked us over with!!) will be no problem. image

And know if y sent them back for bearing changes or had some issue Iā€™m sending back with the true 12mm axle and thatā€™s been the hold for u as well.

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Nice! I am also looking for a mini lathe. Here in EU second had are impossible to find! New costs a lot :weary: I do work on a big one but I would like a small one to have it at home and do my diy parts. really nice.

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Bigger lathe the better my machinist friend insists and Iā€™m finding out. Today will be cutting drill bits to half their size to fit in the back stock chuck to use them. And he says when big less vibrations and more accuracy, and u can get better accuracy by being able to chuck things closer to the center of the chuck with itā€™s bigger hole.

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absolutely true, I use one that is like 900Kg and you can put more stress on it and be faster and more precise. Although with the small one you can do great stuffs, but you have to go way slower. I would say if you have to make multiple parts in series than go bigger, otherwise a small one is fun tooā€¦ There are middle size lathe around 300kg that can really work with really low tolerance, but then again the cost rises a lot

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image image image Because the motors are almost done w the bearings already on, and removing them will probably damage them, I have to center the part for drilling by holding further and on the stator,the green, and my new lathe is too small and so is the one down the street I use. So gunna get different jaws or another lathe pronto. I would grind the jaws down but was told it would be too Hard. I also got a drill press a week ago with the same goal but opted for the lathe as soon as I got it and then this, so itā€™s a learning experience here. So close. Sorry guys thereā€™s seemingly endless final hurdles. Itā€™s probs raining :umbrella: in Europe now.

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Has anyone else had any issues with the axels bending? Tbh I am happy to have mine as normal non lathed and if I have any problem then Iā€™ll happily pay to send them back to be sorted. Is that an option Hummie?

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That is. That will get u them sent in a day or Two max. Otherwise thereā€™s a bit Longer while we figure how to get this lathed. If u want me to send them now no problem and happy to as long as youā€™re aware of what of the risk. The risk I Believe being possibly bending, not breaking.

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I have put in a few hundred miles on it without any issue. On the other hand my front Paris hanger bent somehow so I just took a new from hummie since he has a bunch left from taking the baseplate for the hubs. Donā€™t wanna deal with their warranty when I can get replacement. :slight_smile:

P.S. San Francisco officially has the worse road in the US.

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You know you can switch the jaws around donā€™t you? Your lathe should also come with another set of jaws for clamping bigger outside diameter pieces.

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He tried that. Itā€™s not long enough to reach the stator. Thereā€™s no way without modification you can mount the whole assembly on to this mini lathe.

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Doesnā€™t the lathe also come with outside jaws?

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It does and they donā€™t reach far enough to the stator with that bearing on.

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Ok then in that case you could easily grind out the portion of each jaw that gets in the way. You could also do that on the lathe but since this is a small hobby lathe it would probably be easier to just grind them. It should not take more the 30ā€™ for all 3 jaws to be modified.

image

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