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MSuper V3s+ Violent Shaking


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Regarding the clear heat shrink, it might have a higher melting point than the hard black plastic connectors so that may be why they swapped it out.  If you Google clear heat shrink tubing, FEP can withstand 204 C continuous temperatures.  Hopefully the connectors are not getting that hot ( @Rehab1 , could you attach your temp logger at the connector and climb some hills to see how hot they get?)

If the black hard plastic sheaths are melting and allowing electrical conduction to occur they are pretty useless then.  Installing a high temperature resistant cover that doesn't melt would help secure the connection while avoiding short circuits.  Why not get rid of the weak link if the black sheaths are melting rather than cover them over with something else?  If that's their thinking that could be a logical reason why they are going this route.  It also allows customers to visually and easily see that their motor connectors are actually crimped.

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3 hours ago, Hunka Hunka Burning Love said:

Regarding the clear heat shrink, it might have a higher melting point than the hard black plastic connectors so that may be why they swapped it out.  If you Google clear heat shrink tubing, FEP can withstand 204 C continuous temperatures. 

 

 

I will contact @Jason McNeil to see if he has any of the clear tubing in stock. I would like to perfom a heat /temperature test on that tubing against the heat shrink sleeves I used. 

4 hours ago, Hunka Hunka Burning Love said:

Hopefully the connectors are not getting that hot ( @Rehab1 , could you attach your temp logger at the connector and climb some hills to see how hot they get?)

That would be an excellent test! Unfortunately there is zero room to place the temp data logger at that location. If I can find a data logger with a probe I could place the probe between the 2 layered heat shrink tubes I used to obtain temperature readings.

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23 hours ago, Michael Vu said:

 

E21j4Bk.jpg

Wow, what the heck is that? This looks like hand soldered by an amateur! Don't they have a reflow oven to put the boards in for soldering? This would never ever make it through QC in our company. I wonder what machine they use for QC of the solder joints, or if they use one at all. Normally, every board runs through a machine which does an optical analysis of every single solder joint on the board (AOI). These machines detect some 20 different possible defects, including tombstone, bridges, component shifts, or cold solder joints. We use them for every piece of hardware we manufacture, and our devices are much less safety critical (building automation controllers).

Also, what's that goo on the chip right there? The other (square) controller looks very suspicious as well, at least on this picture. Could you get a clear/sharp image of the board? This really looks totally flakey, I would not dare to ride a wheel with such a board in it.

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14 minutes ago, Christoph Zens said:

Could you get a clear/sharp image of the board? This really looks totally flakey, I would not dare to ride a wheel with such a board in it.

Weird, that looks exactly like the ACM board I got from Rehab. Here's a 4640 x 3480 image, I've removed the silicone and the coating from the chips with IPA (isopropanol / isopropyl alcohol), as surprisingly the coating would dissolve with it, and removed the heatsink (no, the mosfets weren't bent like that before it ;)): Link to large image

Probably not the sharpest possible image. Maybe the weird stuff on the chip on Michael Vu's images is reflections from the coating and some splattered silicone/whatever the white gooey stuff is?

 

 

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6 minutes ago, esaj said:

Weird, that looks exactly like the ACM board I got from Rehab. Here's a 4640 x 3480 image, I've removed the silicone and the coating from the chips with IPA (isopropanol / isopropyl alcohol), as surprisingly the coating would dissolve with it, and removed the heatsink (no, the mosfets weren't bent like that before it ;)): Link to large image

Probably not the sharpest possible image. Maybe the weird stuff on the chip on Michael Vu's images is reflections from the coating and some splattered silicone/whatever the white gooey stuff is?

 

 

Thanks, it looks like the same board (electrically). However, the solder job on yours is much better, although still hand-made it seems.

Here is what a QC failed board looks like. Note that it was produced in 2011 and I had it in my pocket as a key fob for a long time, so it's oxidated and not clean, but note the shape of the solder joints on the yellow caps and the pins of the FLASH (IC). That's how reflow soldered components look like. Since everything on this board is much smaller than the GW one, I had to take the picture through a magnifying glass, that's why it is a little distorted... Pin spacing on the chip is 0.5mm in real size...

IMG_20170612_221115.jpg

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3 minutes ago, Christoph Zens said:

Thanks, it looks like the same board (electrically). However, the solder job on yours is much better, although still hand-made it seems.

Here is what a QC failed board looks like. Note that it was produced in 2011 and I had it in my pocket as a key fob for a long time, so it's oxidated and not clean, but note the shape of the solder joints on the yellow caps and the pins of the FLASH (IC). That's how reflow soldered components look like. Since everything on this board is much smaller than the GW one, I had to take the picture through a magnifying glass, that's why it is a little distorted... Pin spacing on the chip is 0.5mm in real size...

IMG_20170612_221115.jpg

The joints on the tantalums and other caps looks "rough" and uneven, can't really tell about the IC, to my untrained eye it looks fine :D  I made a small reflow-oven from a toaster oven, and got somewhat similar results:

s5CTgbz.jpg

Well, maybe a bit smoother than on your example board, but the joints aren't really smooth, plus there's lots of flux left-over that wasn't cleaned yet when this picture was taken. Probably should have heated it a bit longer. And I suck at dispensing the paste, there was too much on many points :P Haven't really used the oven much though, mostly I solder by hand with a cheapo 20€ soldering iron (and "cheat" by using 1206's and larger pin-pitch ICs  :ph34r:)

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10 minutes ago, Christoph Zens said:

Thanks, it looks like the same board (electrically). However, the solder job on yours is much better, although still hand-made it seems.

Here is what a QC failed board looks like. Note that it was produced in 2011 and I had it in my pocket as a key fob for a long time, so it's oxidated and not clean, but note the shape of the solder joints on the yellow caps and the pins of the FLASH (IC). That's how reflow soldered components look like. Since everything on this board is much smaller than the GW one, I had to take the picture through a magnifying glass, that's why it is a little distorted... Pin spacing on the chip is 0.5mm in real size...

IMG_20170612_221115.jpg

That's cool, and I love see quality work. I'm not defending Gotway with my next statement, but attempting to address reality.

China is a country of ~1.4 billion people, the vast majority being poor by our standards. They still exist in the part of the graph where labor is much cheaper than machinery. So it can't be a surprise that a small company like Gotway still uses hand soldered boards (if that is what they're doing here) instead of investing in the reflow technology.

This is what's frustrating about being an early days EUC enthusiast when the EUCs are made in a third world country :(

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4 minutes ago, esaj said:

The joints on the tantalums and other caps looks "rough" and uneven, can't really tell about the IC, to my untrained eye it looks fine :D  I made a small reflow-oven from a toaster oven, and got somewhat similar results

Yes, the IC worked out OK but the tantalums had problems. C206 was shifted out of position a lot, which compromized the lower joint. Things like this are normally found by AOI and the boards are sorted out. They operate with light and the reflections a good solder joint produces. Yours have too much paste, but that's normal with hand-made boards. Our SMT machines apply paste through a mask layer so it's very thin and should be even.

You know what works well with home-made boards using solder paste? A hot air gun. We use them a lot for prototyping. Works really well. First put on the paste, place the components and then go over the board with the hot air gun. Well, that's off topic now. Sorry. This is such an inportant thread, really.

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4 minutes ago, Marty Backe said:

That's cool, and I love see quality work. I'm not defending Gotway with my next statement, but attempting to address reality.

China is a country of ~1.4 billion people, the vast majority being poor by our standards. They still exist in the part of the graph where labor is much cheaper than machinery. So it can't be a surprise that a small company like Gotway still uses hand soldered boards (if that is what they're doing here) instead of investing in the reflow technology.

This is what's frustrating about being an early days EUC enthusiast when the EUCs are made in a third world country :(

I can imagine that. On the other hand, it's China where most of todays high tech is manufactured (iPhone included), so they can do it. But it may not be accessible to everyone. Still, they could order their boards from Foxxcon or a similar company. I am sure there are many of those even in the Shenzen area. We do all of our production in Europe and some 40% of the investment in building the SMT line was government-funded, because they want companies to do high tech here instead of doing design only and have everything manufactured over in China.

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23 minutes ago, Marty Backe said:

That's cool, and I love see quality work. I'm not defending Gotway with my next statement, but attempting to address reality.

China is a country of ~1.4 billion people, the vast majority being poor by our standards. They still exist in the part of the graph where labor is much cheaper than machinery. So it can't be a surprise that a small company like Gotway still uses hand soldered boards (if that is what they're doing here) instead of investing in the reflow technology.

Despite lacking quality, I tip my hat to anyone who's capable of soldering that small components by hand, I tried SC74's and 0603's once, and failed miserably :D And those aren't even really small...

The machinery is probably pretty expensive for a (relatively) small-time company. KS had the advantage that they already have the equipment & machinery for SMD-work (masks, pick&place, reflow-ovens, automatic inspection etc), as they did other stuff before (like BMS-boards). They posted a video on the forums earlier, which I then put up on Youtube (I did ask for permission, but they never responded... did it anyway :P

It's a bit stuttery at points, but shows that they have invested in the machinery and production a lot. I don't think Gotway-wheels are really bad, but have seen enough incidents that I personally stay away from them. ;)  KS speed is enough for me.

 

Quote

This is what's frustrating about being an early days EUC enthusiast when the EUCs are made in a third world country :(

Is China really a 3rd world country? I thought it was 2nd world... but then again, I'm not even sure what the criteria is for 2nd & 3rd :P

 

19 minutes ago, Christoph Zens said:

Yes, the IC worked out OK but the tantalums had problems. C206 was shifted out of position a lot, which compromized the lower joint. Things like this are normally found by AOI and the boards are sorted out. They operate with light and the reflections a good solder joint produces. Yours have too much paste, but that's normal with hand-made boards. Our SMT machines apply paste through a mask layer so it's very thin and should be even.

You know what works well with home-made boards using solder paste? A hot air gun. We use them a lot for prototyping. Works really well. First put on the paste, place the components and then go over the board with the hot air gun. Well, that's off topic now. Sorry. This is such an inportant thread, really.

Never thought of that, I assume you mean the kind they sell in hardware stores. I've been meaning to buy a hot-air station for quite a while, but can't really justify spending 500-1000+€ on something like JBC/Hakko/Weller/whatever high-quality professional equipment manufacturers there are, and then again, I'm a bit cautious about the cheapo units, as you never know about the quality (or lack thereof). Probably should just bite the bullet and get some 100-200€ Ayoue or whatever...

Sorry for the off-topic :P

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15 minutes ago, esaj said:

<snip>

Is China really a 3rd world country? I thought it was 2nd world... but then again, I'm not even sure what the criteria is for 2nd & 3rd :P

<snip>

There are still vast areas of China where people still crap in channels in the ground. I call that 3rd world. But granted I'm not an authority.

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25 minutes ago, Christoph Zens said:

I can imagine that. On the other hand, it's China where most of todays high tech is manufactured (iPhone included), so they can do it. But it may not be accessible to everyone. Still, they could order their boards from Foxxcon or a similar company. I am sure there are many of those even in the Shenzen area. We do all of our production in Europe and some 40% of the investment in building the SMT line was government-funded, because they want companies to do high tech here instead of doing design only and have everything manufactured over in China.

Totally agree that "China" can do it, but Gotway is actually making these wheels and I'm pretty sure they don't have the resources of Foxxcon.

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44 minutes ago, Marty Backe said:

Totally agree that "China" can do it, but Gotway is actually making these wheels and I'm pretty sure they don't have the resources of Foxxcon.

What I wanted to say is that they can simply have Foxconn or any other contract manufacturer solder the boards for them. That's what we did until we built our own SMT line. It's simple and not really expensive either. You send the bare PCBs and the BOM (bill of materials) and they will order the required parts (or have them in stock anyways), stuff them, solder the boards, and test them. With lot sizes of 200 - 500 pieces, I am not sure if that wouldn't even be less expensive than manual production. Even if a little more expensive, a more reliable product may be worth a few dollars extra for the board, I guess. But maybe they get the boards as they are from some other company and don' really build them.

Edit: Just found out that Foxconns largest factory with somewhere between 200.000 and 400.000 employees is located in Shenzhen, so GW would have their contract manufacturer right around the corner... ;)

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1 hour ago, esaj said:

Despite lacking quality, I tip my hat to anyone who's capable of soldering that small components by hand, I tried SC74's and 0603's once, and failed miserably :D And those aren't even really small...

I agree that the GW boards are not soldered by hand. 

 

2 hours ago, Christoph Zens said:

 

On 6/11/2017 at 3:42 PM, Michael Vu said:

 

E21j4Bk.jpg

Wow, what the heck is that? This looks like hand soldered by an amateur! Don't they have a reflow oven to put the boards in for soldering? This would never ever make it through QC in our company.

 

I took some photos of my new 'spare' ACM board that I just received. It shipped from China 6 weeks ago and it does not have the maladroit soldering depicted in the photo.

 

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22 minutes ago, Rehab1 said:

I agree that the GW boards are not soldered by hand. 

I don't know if they're soldered by hand or not, at least there's some slightly misaligned components in your old board, but I can't tell for sure either way just by looking at the joints... It's not impossible to solder really small components, I know people who solder 0201's (imperial code, smaller than the ones used on the Gotway boards) by hand, and with an iron, not hot-air station :o  And then there was that one video I posted a while back, where the guy solders a 01005 (imperial code, which is a speck of dust) by hand with microscope :wacko:  I just suck at soldering really small components :P , probably it would get better over time, but I've got a good stock of 1206's, so I use those for the time being. Also with slightly larger components it's not so critical if milling a board goes a bit awry (too wide isolation or the runout / too high feed-speed causes burrs at edges), but if I had to make really small pads for small components, and the copper comes off, I'd have to start over each time.

On the other hand, looking at the amount of components on the Gotway-boards, I'd think it'd be actually more expensive to have it done by all the way by hand (slow = lots of hours) even with low wage vs. having them made in larger batches in some cheaper manufacturer. If they're made by machines or at least partially automated, maybe the equipment just isn't very top notch or they skip the inspection stage or aren't that picky and just check that the board works in general... but I'm just guessing.

330px-SMT_sizes,_based_on_original_by_Zu

 

 

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3 minutes ago, Rehab1 said:

I agree that the GW boards are not soldered by hand. 

 

I took some photos of my new 'spare' ACM board that I just received. It shipped from China 6 weeks ago and does not resemble the maladroit soldering job depicted in the photo.

 

That one looks much cleaner, but I think it's not from an SMT line. At least paste and components are placed by hand. Amount of solder is too much for mask printed paste, and component orientation is very inconsistent. Looking at the row of 330 Ohm resistors at the left: They should be all the same orientation when auto-placed, but on this board they are rotated 180 degrees on a random basis. No SMT line would do this (with a sane programming). It may have seen a reflow oven for soldering though...

Manual or not, this board looks good to me. Structure size is pretty big on those boards, so technically no problem to do these by hand, if done correctly. As long as is doesn't get smaller than 0603 and there are no BGAs involved, it doesn't have to be done by machines. It just increases reliability a lot if there isn't a human picking components from boxes and hopeully putting them in the right spot and the right orientation on the board. There is a lot of room for error. Most failures on our boards come from the very few parts that have to be placed manually (through-hole caps), although soldered by machine later on. People inserting the caps get the polarity wrong, even though they have a 50% chance of getting it right without even looking. Luckily AOI can detect it via the marking on the caps...

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25 minutes ago, Christoph Zens said:

Looking at the row of 330 Ohm resistors at the left: They should be all the same orientation when auto-placed, but on this board they are rotated 180 degrees on a random basis. No SMT line would do this (with a sane programming). It may have seen a reflow oven for soldering though...

At least many of the tapes I've got from Aliexpress have the resistors in random orientation already, so they could still be placed by machine, and then move a bit in the oven (to explain the angles/positions slightly shifting here and there)?

5uoh0YZ.png

Hand-soldered/placed or not, while the boards aren't probably "on-par" with the western quality standards, I don't think there's (so far, knock on wood) been any cases where a fault could have been traced to a bad solder joint on the board (the earlier soldered motor connectors were another issue).

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51 minutes ago, esaj said:

At least many of the tapes I've got from Aliexpress have the resistors in random orientation already, so they could still be placed by machine, and then move a bit in the oven (to explain the angles/positions slightly shifting here and there)?

 

Hand-soldered/placed or not, while the boards aren't probably "on-par" with the western quality standards, I don't think there's (so far, knock on wood) been any cases where a fault could have been traced to a bad solder joint on the board (the earlier soldered motor connectors were another issue).

Reading this ongoing thread is continuing education :)

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3 hours ago, esaj said:

Is China really a 3rd world country? I thought it was 2nd world... but then again, I'm not even sure what the criteria is for 2nd & 3rd :P

I bet they are 1st world, with 2nd and 3rd parts in the same country,  just like the US.;)  Thanks for reposting that video, it was very well made.  It makes Kingsong look serious about quality.  That is one of the things I like about Kingsong.  Gotway and Kingsong are fighting it out, and every other manufacturer is left in the dust.

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2 hours ago, Christoph Zens said:

Manual or not, this board looks good to me.

Zens quality seal of approval! Thanks!  I'll take any QC assurances I can get!:)

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4 hours ago, Marty Backe said:

There are still vast areas of China where people still crap in channels in the ground. I call that 3rd world. But granted I'm not an authority.

In America that's called an Outhouse.:)

 

 

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1 hour ago, Rehab1 said:

In America that's called an Outhouse.:)

 

 

Oh man, you're killing me :laughbounce2:

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