Search found 95 matches

by Barndom
Mar 08 2017 12:10pm
Forum: Motor Technology
Topic: Reducing motor weights... with Al wire?
Replies: 11
Views: 1255

Re: Reducing motor weights... with Al wire?

I wonder how this Siemens motor is build? (https://arstechnica.com/cars/2016/12/this-extra-330-is-the-fastest-climbing-electric-powered-airplane-ever/): ...unveiled the SP260D, an electric motor that weighs 110lbs (50kg) and produces 260kW (348hp)—a power-to-weight ratio of five kilowatts per kilogr...
by Barndom
Mar 02 2017 10:53am
Forum: Motor Technology
Topic: Reducing motor weights... with Al wire?
Replies: 11
Views: 1255

Re: Reducing motor weights... with Al wire?

Yes, it's an old tread but I'm not totally convinced aluminium wire armatures is without benefits. Particular power/weight factor. It seams like some coreless motors use alu wire according to sinotech . Recent advances in coreless motor design include the replacement of AlNiCo with samarium-cobalt s...
by Barndom
Aug 27 2015 11:02am
Forum: Battery Technology
Topic: What is the recommended discharge rate lead AGM battery.
Replies: 25
Views: 1182

Re: What is the recommended discharge rate lead AGM battery.

2,5 C should be SAFE with good margins. Otherwise I'll be surprised.
I do 4 C under a few minutes on my electric skateboard with SLA's and they do not get hot. While doing 2 C on average i get around 4,5 Ah out of the 7 Ah battery.
by Barndom
Aug 12 2015 9:18am
Forum: Stand-up E-scooters and E-skateboards
Topic: Belt slip stopper, idea.
Replies: 9
Views: 1594

Re: Belt slip stopper, idea.

Looks good :) ... . I wonder why I never saw any such implementation before, and nothing similar in timing belts engineering documents.. It surprise me also.. I was a bit worried that the motor axel and bracket could bend if the forces being big when the belt tries to lift, but see that you have an ...
by Barndom
Aug 12 2015 6:52am
Forum: Stand-up E-scooters and E-skateboards
Topic: iSkate Classic 600W way too loud or damaged?
Replies: 5
Views: 621

Re: iSkate Classic 600W way too loud or damaged?

Totaly normal sound for this kind of board. A bit annoying, but at least people get out of your way when you approach them from behind.
by Barndom
Aug 03 2015 12:07pm
Forum: Stand-up E-scooters and E-skateboards
Topic: Belt slip stopper, idea.
Replies: 9
Views: 1594

Re: Belt slip stopper, idea.

This is not a belt tensioner even if it can be placed to duoble act as one (or actually a pulley that wrap the belt to get more teeth in mesh, since the belt is supposed to be tight anyway). If one want to use a HTD-3 belt or a HTD-5 with few teeth en mesh to get higher gear reduction the belt can s...
by Barndom
Aug 03 2015 8:29am
Forum: Stand-up E-scooters and E-skateboards
Topic: Here come the clones..
Replies: 146
Views: 24019

Re: Here come the clones..

melonboard indiegogo is becoming a place for reselling Chinese products... https://www.indiegogo.com/projects/melonboard-electric-skateboard#/story From the website FAQ: "Can I brake going downhill? No, the motor may get overheated. For the riders safety we highly recommend not to go down hill. The...
by Barndom
Jul 15 2015 8:28am
Forum: Stand-up E-scooters and E-skateboards
Topic: Belt slip stopper, idea.
Replies: 9
Views: 1594

Belt slip stopper, idea.

When the belt slips it have to lift out of the toothed pulley. If one can prevent this lift the belt can’t slip. It can be done with a wheel on the outside of the belt, either active that are in contact with the belt or passive with it hoovering just a hair above the belt so it doesn’t create any ex...
by Barndom
Jun 18 2015 9:53am
Forum: Stand-up E-scooters and E-skateboards
Topic: Watt meter connected to E-skateboard.
Replies: 28
Views: 3158

Re: Watt meter connected to E-skateboard.

buzztiaan wrote:FYI on SLA , you get less than original capacity if you discharge above ~0.1C, which i guess you are doing?
Yes, the more you load it the less the capacity. I top out at 5C and use 1C on everage. Of the 7 Ah i get out about 4 to 5 Ah wich was more than I expected.
by Barndom
Jun 17 2015 12:50pm
Forum: Stand-up E-scooters and E-skateboards
Topic: Watt meter connected to E-skateboard.
Replies: 28
Views: 3158

Re: Watt meter connected to E-skateboard.

I while ago I tested the timing. I connected the motor cables to a bench supply with adjustable voltage and ampere. I had the voltage set to a fixed 29.0 V and the ampere set to max. When the timing on the motor is moved the A is affected. The wheel was connected but spinning in the air. The current...
by Barndom
Jun 17 2015 10:25am
Forum: Stand-up E-scooters and E-skateboards
Topic: My longboard build thread...
Replies: 65
Views: 4835

Re: My longboard build thread...

Im sure you have evaluated the option to use the original motor bracket (like in this thread ) but have good reasons not to. Allthou the bracket you did look good with the reinforcement bar, the exskate one is pretty heavy duty I believe. The old 100w motor probably weights as an 6374 outrunner at l...
by Barndom
Jun 11 2015 12:03pm
Forum: Alternative Energy
Topic: An idea for clean power
Replies: 48
Views: 8396

Re: An idea for clean power

Have you heard about Seawater Greenhouse? Those guys are in South Australia and have proof of concept examples of using nothing but seawater and solar power to grow commercially viable fresh fruit and vegetables. Next they are going to try to do chickens. Fascinating stuff: http://www.guardian.co.u...
by Barndom
Jun 02 2015 9:46am
Forum: Stand-up E-scooters and E-skateboards
Topic: Have anyone tried Hub motors on a EMTB?? If not why not?
Replies: 4
Views: 580

Re: Have anyone tried Hub motors on a EMTB?? If not why not?

JayE wrote:...Firstly why have no one used hub motors on a EMTB? ...
Se first post, this was back in -07.
by Barndom
May 26 2015 10:27am
Forum: Stand-up E-scooters and E-skateboards
Topic: Another Electric Onda Board..
Replies: 28
Views: 5937

Re: Another Electric Onda Board..

If 1:3 doesn't work out with the wheel size, I have the printer to reiterate until I get it right. I already have a 20t motor and 40t wheel gear printed just in case. .. 20 to 40 (1:2) will be even worse ;-) I think that a reduction of 1:4 to 1:6 will fit these wheels best. That shall also put less...
by Barndom
May 25 2015 12:33pm
Forum: Stand-up E-scooters and E-skateboards
Topic: 10S custom skate ESC: testers wanted!
Replies: 1520
Views: 187566

Re: 10S custom skate ESC: testers wanted!

Has anybody done some tests with higher currents or in RC cars yet? I'm planning to put the VESC in my RC car. I don't have exact numbers, but from what I have seen in comparable setups it draws somewhere between 100 and 200A during acceleration (with RC ESC without current control). But that is on...
by Barndom
May 13 2015 7:33am
Forum: Stand-up E-scooters and E-skateboards
Topic: Another Electric Onda Board..
Replies: 28
Views: 5937

Re: Another Electric Onda Board..

The gear reduction of 14 to 42 seams a bit small for those big wheels. May bee a bit uneffective.
by Barndom
May 07 2015 9:17am
Forum: Stand-up E-scooters and E-skateboards
Topic: 10S custom skate ESC: testers wanted!
Replies: 1520
Views: 187566

Re: 10S custom skate ESC: testers wanted!

How about a push mode? Essentually it is that the motor drives the load from the friction of the belt and the motor itselfes and the extra weight of an e-board. So when you push the e-board it is as easy as a regular longboard. This could be achived by having a fixed low current at about 1 A or so. ...
by Barndom
May 07 2015 7:57am
Forum: Stand-up E-scooters and E-skateboards
Topic: |Pen E-Board| Smallest E-board ever|Friction Drive|
Replies: 126
Views: 16168

Re: |Pen E-Board| Smallest E-board ever|Friction Drive|

Since you are driving the wheel using the outer diameter of the motor as a friction drive, you must have a system that prevents the power wires from becoming tangled due to the rotation of the motor. Please describe this system. On this board an 'outrunner' motor is used, the wires are in the cente...
by Barndom
May 06 2015 12:52pm
Forum: Stand-up E-scooters and E-skateboards
Topic: Took my first real hit to the floor
Replies: 3
Views: 380

Took my first real hit to the floor

I was driving through heavy rain on a smoth concrete roller-derby course. The board slipped and I was on my stomach. Didn’t hurt myselfe at all :) The remote slided some 10 yards away. I stand up and felt the concrete was slippery as ice. I have fallen of the board one time when I was jumping on it ...
by Barndom
Mar 31 2015 3:55am
Forum: Stand-up E-scooters and E-skateboards
Topic: Rubberwheels vs. PU?
Replies: 3
Views: 726

Re: Rubberwheels vs. PU?

My wheels are solid rubber (edit above). They was very common on comersial e-boards before. I've read that (soft) PU's runs smother than the Rubbers but also the opposit. According to the chart above rubber is softer but I beleave that rubbers also come in different hardness. What I read is that PU'...
by Barndom
Mar 30 2015 10:36am
Forum: Stand-up E-scooters and E-skateboards
Topic: Struggling with choosing an electric longboard for commute
Replies: 15
Views: 1772

Re: Struggling with choosing an electric longboard for commu

... Now I'm 41.... and it's 25 years later. The familiar muscle memory seems to come back quickly when I get on a skateboard but I'm not sure how well that will translate into handling an electric skateboard at 20MPH. I'm physically in good shape and active. My main concern is really about the dang...
by Barndom
Mar 30 2015 5:20am
Forum: Stand-up E-scooters and E-skateboards
Topic: Rubberwheels vs. PU?
Replies: 3
Views: 726

Rubberwheels vs. PU?

Hello! I have a Fiik clone and have thoose 115 mm solid rubberwheels on alu rims (see pic below). I planning to mount ABEC 11 Electric Flywheels to get more milage through less rolling resistans PU and real skate bearings (Im planning on the Bear 10 mm for the ABECs, wont't fit the rubbers with 26 m...
by Barndom
Mar 19 2015 9:04am
Forum: Stand-up E-scooters and E-skateboards
Topic: 10S custom skate ESC: testers wanted!
Replies: 1520
Views: 187566

Re: 10S custom skate ESC: testers wanted!

Parallel vs series wired motors would only be applicable on DC bruched motors, wouldn't it? Not realated to the VESC then :wink:
by Barndom
Mar 18 2015 11:29am
Forum: Stand-up E-scooters and E-skateboards
Topic: 10S custom skate ESC: testers wanted!
Replies: 1520
Views: 187566

Re: 10S custom skate ESC: testers wanted!

...By the way, a problem I noticed with the diagonal motor mount is that the board tends to lean/steer in one direction when accelerating hard, which isn't that nice. I think I would prefer to have both motors on the same truck. Or 4 smaller motors :-) Will it steer if you drive you're diagonal dri...
by Barndom
Jan 09 2015 10:55am
Forum: Stand-up E-scooters and E-skateboards
Topic: Looking for HTD-5 pulley.
Replies: 8
Views: 1086

Re: Looking for HTD-5 pulley.

Good point. I didn't know that back then. Also there probably isn't a HTD-5 belt with 4 less teeth. I'm not particular keen on make the holes oval either, don't think it will hold/work. But im thinking about an idler pulley to take up the slack. The idea is to route the belt above the lower of the t...