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Friday, June 4, 2010

Learning Lessons

Well, after over 4 months since ordering, the remaining 3 stators are here. And what did I get for my trouble? Express shipping to the wrong address and a 15% coupon. Wow, gee, thanks...

Yeah, I'm pissed off. The express shipping meant that they couldn't change the address before it was delivered. Now I might not be able to get them for another 3 months. Anyone know what MIT does with mail sent to closed dorm addresses over the summer?

Needless to say I am most dissatisfied with GoBrushless. One of the most incompetent merchants I've ever dealt with. However, it wasn't completely their fault because their supplier in China is mostly to blame. Though the shipping error was completely their fault.

Anyways, I'll get them eventually. I'm glad I didn't have to do a total redesign, or cut up a motor ((like one of these) for a stator, the latter of which would have resulted in at least a slight redesign.This experience taught me the value of flexibility; unfortunately, brushless motors aren't very flexible. I still should have designed for more available parts (stators); GoBrushless is currently the only source for 65mm stators. Believe me, I know. I've spent hours and hours scouring Google for another source- nothing.

In summary, here are the lessons I've learned:
1. Always ask about stock status of a part before ordering.
2. Stators (or anything) from China could take many months.
3. Design for available parts/design for flexibility.
4. For what you pay for custom USA parts, you get back in time. For example, if I had gone with ProtoLam, I could have designed exactly the stator I wanted and I probably would have had all four of them in less than a month, but it probably would have cost four times as much. (There's also a quality advantage to USA parts, but that's a different story.) However, in the real engineering world, the net cost of waiting four times as long would have outweighed the higher production costs.
5. Repeatedly to the point of exhaustion remind the merchant of the correct shipping address.

I found out something else, too. These stators, and some other ones GoBrushless sells, are the same (as in from same supplier) as the ones in Scorpion motors. However, Scorpion doesn't officially have a 65mm motor out yet, though apparently that's coming soon along with 85mm ones. Scorpion is also developing wind generator motors, so they could potentially be a source for large stators. I bet they'd sell you stators directly if you contacted them.


  1. Some times a redesign is worth it if you can use stock parts or common ones. I've definitely pulled that a few times.

    Also, when you signed out of your dorm, they should have made you fill out a redirection form where you can put your summer address.

  2. Yeah, they did. I called them today and it's going to get forwarded. Phew...