Heat sinks, Screwdrivers and the Lessons...

Dave Hrynkiw
March 28, 2012

You would think in these days it would be a simple task to source something you want to have made. After all, MAKE, the Internet and the world "getting smaller" would have you think that it'd be an easy task. Sometime it is, and sometimes it's like this!

We've been to Hong Kong and China a few times on business (and wow, HK is an amazing place to shop/visit), so we're not amateurs at the whole global-sourcing thing, but we've recently tripped up on a few purchases, and thought I'd share the story, and share some lessons learned.

The Heat Sink: Years ago, we developed the "Compact Motor Driver" breakout board for the L298 IC. It has a strange, breadboard-hostile footprint, and so we made it usable, and it's become a popular product (if not evolved and well-duplicated by others - yay OSHW!). But many of these derivatives use a nice-sized heat-sink that we'd also like to adopt into our design.

It's been a tedious search, finding extrusion & heat-sink manufactures and digging through the datasheets (not the best use of my time, but fun, nonetheless!). Finally, we've been able to locate a few factories by asking makers of the derivatives  and found ones in in India (almost exactly 1/2 around the globe), but they're not interested in shipping outside of India. Other candidate manufactures either don't follow up multiple requests, or have dead contact links.  Even domestic suppliers like the usually-excellent Aavid Thermalloy has let us down by not having the right footprint, but similar L298 / T0220 heat-sinks are on Ebay, but the lack of accountability and quality-assurance scares us from buying volumes there. They've got to be manufactured somewhere, but finding a source is harder than it seems! The search continues...

Lessons learned in this process:

  • Don't assume a simple component will be an easy-to source component.
  • Don't fear asking other manufacturers where they get theirs. The worst that can happen is... nothing!
  • Finding your treasure is one thing. Bringing it home is another (shipping can kill an idea).
  • Finding the ideal supplier is difficult! i.e.:
  • Ebay vendors tend to be "department stores". They may have the part you want, but also sell everything from cellphone accessories to lingerie at the same time. Expect low quality-control and low supply reliability. Expect to pay 2 or 3 levels of markup on products from here.
  • In addition to "department stores", Globalsources.com & Alibaba.com also attract "representatives", who sell families of similar product. You should be able to find better quality & supply reliability, but not usually at a price savings over Ebay (where you get what you pay for).
  • Factory level suppliers are ideal, if you are able to buy the "MOQ" (Minimum Order Quantities) the factory deals with. You won't get a response for a request of 200 pieces; Maybe for 2,000. Prices & quality will be the best, but they'll expect you to know what you're talking about, and will build/deliver precisely to your communications. Can be an expensive learning curve!

 

The Screwdriver: Ever find a really cool tool, and then not be able to find it again? This is sort of like that. Like all hackers, a quality tool is worth holding onto, and this one came from the toolbox of Mark W. Tilden when he sold it to me as part of his household reduction before moving off to Hong Kong. What a great little device. It's a house-brand MasterCraft (of Canadian Tire, here in Canada). Nice size for holding onto 4-40 bolts with your finger tip with lots of control. Trust me, use it for an hour, and you'll be hooked. I want to share this design with the world, as giveaways, for sale, in kits - whatever. It's that good.

The best screwdriver in the world

You'd think there would be a tool manufacturer somewhere that has these or a similar version. After fruitless search going through traditional Asian source websites (alibaba.com, globalsources.com), the rapid realization was that this was the place to buy crappy tools. Un-heat-treated tool tips are a dead-giveaway that this won't last longer than your first stuck screw. Continuing the search to several of the prime tool manufactures in North America came back with "Well, we have this one that's sorta the same... but longer. And fatter. But other than that, it's the same thing." Sigh.

The search continues, but there is hope! Thanks to today's MAKE Tool Review, I have hope that indeed quality tools can still be sourced... somewhere!

Lessons learned:

  • Tools shopping is best in person. Handling samples at Trade shows are an excellent way. Next best way is to request/order samples.
  • The best quality tools seem to be of North American / European manufacture. Or at least that's where the head-offices are. Apex Tool, Bondhus, Gray, Klein, Snap-on, Wiha. Unfortunately, we haven't had much luck here. (Wiha interchangeable tip screwdrivers come close, but not quite the same)
  • Inexpensive, low-quality Asian tools add huge "noise" to web-searches. It is very difficult to filter out "toy" tools when searching for quality Asian suppliers.
  • Vendors jealously guard their sources! And understandably so, after experiencing the troubles we've had. Thanks to SparkFun for sharing some of their sources with us in the past. A little quid pro quo goes a long way in the OSHW community!

So when you see your favourite vendors featuring something new and cool they've found to resell, keep in mind it isn't as easy as flipping open a catalog and pointing. It often takes surprising effort to find, sample, evaluate, ship, and stock the cool tools & toys!

 

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