Hacking Manufacturing: Ordering A Custom Heatsink From China

a black aluminum heatsink with fins on a green matt

Building a one-off hack is fun. But what happens when people like your hack so much they want to buy it? As many of us have discovered, going from prototype to product can be a frustrating, tedious, and often expensive process. [Nick] at Arachnid labs has documented the process of manufacturing a custom heatsink in China.

While designing the Re:Load Pro, [Nick] discovered that there were no enclosures with integrated heatsinks which suited his application. Rather than design an entire case from scratch, [Nick] used an aluminum extrusion. This is a common technique in the electronics world, and literally thousands of extrusion profiles are available. The problem was the heatsink. Only a custom part would fit the bill, so [Nick] created a CAD drawing detailing his design. Much like the case, the heatsink was an aluminum extrusion. The custom nature of the heatsink meant that [Nick] would need to pay mold/tooling costs as well as satisfy minimum orders.

heatsink drawing

[Nick] headed off to Alibaba.com and requested quotes from several custom extrusion houses. He received tooling quotes between $500 USD and $1300 USD. Price per unit ranged from $1.85 USD each to $3.50 USD in quantity. The tooling costs are non refundable, so it really pays to get the design right the first time.

[Nick] ended up picking a manufacturer on the lower end of the price spectrum, but not the lowest bidder. Before he placed his order, he asked the manufacturer to send him their own drawing of the heatsink. This may sound like double work, but it’s an extremely important step to verify that the manufacturer completely understands the design.

When everything looked good, [Nick] placed his order and waited for samples. The waiting was the hardest part. Thanks to the Chinese New Year it was over a month before [Nick’s] sample parts arrived. The samples looked great, so  [Nick] is ready to go into full-scale production of the Re:Load Pro heatsinks.

34 thoughts on “Hacking Manufacturing: Ordering A Custom Heatsink From China

      1. He is not going to go large scale with his loadpro… Even if you are doing 1000 units a year modifying an existing product using a jig is far more economical. Set up a jig and you can do the consistent accurate mods over and over again, repeatable and fast.

        Or even buying a bulk extrusion in 1 meter lengths and hire a local shop to do final machining. I found that route to be really cheap.

        1. I understand that this builder is in the UK, but most of the subscribers to hackaday are in the USA. My response was for more than the the builder of this product. I did check-out his web site & it looks like he has a great product!

    1. This was my initial approach. A local machine shop quoted £12 (about USD$20) per unit in production quantities. At that price, it doesn’t take long at all to break even on the machining costs for a custom mould from China.

  1. I love articles like this. Rather impressed that the tooling cost is so low (relatively speaking). I was picturing it to be somethiing comparable to an injection mould tool, which last I checked was easily in the >$3000 range.

    I guess a major “gotcha” is that they will produce exactly what you tell them, so you have to be aware of restrictions like minimum fin width, length, etc. for the extrusion process (which Nick has taken care off).

    The Chinese will have to spruce up their company names though ;-) I once dealt with someone called the “Happy Big Uncle Electronics Manufacturing Co. Inc. Ltd.” (I kid you not). Needless to say, like most of my dealings with the Chinese, they were a pleasure to work with. Which is, sadly, more than can be said for British companies, but don’t get me started on that…..

    1. Yeah my company just did injection molds and they were like twice as expensive, I was with you in thinking that was cheap, I guess it’s just a difference in materials and how much time it takes to make them.

      Yeah unfortunately Chinese suppliers can kill your back-orders and your supply schedule, one wrong thing and it can get stuck at either port (China or USA), and screw everything up.

      It’s a shame no one in the US can compare with their prices even after shipping and throwing out the bad ones(there are always a few).

    2. It’s painful trying to get British companies to be fair. I just did a sensor for current voltage and phase with a PIC an opamp and various Vref / voltage regulators, took it lots of places, emails phone calls and eventually it was a no brainer, could not get sense from anywhere in England but found a company in china that made me one, waited for feedback then ten in boxes, no charge but were prepared to wait for orders.

      1. I can sympathise ;-) When I first started looking to get the PCB for my temperature controller assembled (shameless plug: http://eyejayinstruments.com/), I asked around a few UK board houses and they all ended up insane prices. By contrast, I found Quick-Teck (http://www.quick-teck.co.uk) who actually have a UK office you deal with (no little problems dealing direct with China, all payments, invoices etc are to the UK branch). They’ve been fantastic and very cheap.

        My other continual gripe about UK people: lack of “stuff”, and reluctance to deal with individuals or small orders. Case in point (although this is getting a bit off the track): I wanted 3/4″ grade B/BB Baltic birch plywood for some decorative bases. If you’re in the US (or anywhere else on the planet for that matter), it’s no problem. For example:


        Nice packs, order online, postage included in price. We, however, get stuck with the crappier grades (B/BB is the best grade). I did track down some B/BB, and it worked out at nearly
        twice the price of the US stuff, AND it was Chinese birch, not Baltic. I then spent a whole afternoon collecting and then returning a bit of plywood from someone who claimed it was B/BB when in fact it was BB/CP, which is crappier.

        Aherm. Sorry for the digression.

        1. >My other continual gripe about UK people: lack of “stuff”,
          >and reluctance to deal with individuals or small orders.

          I would say that’s probably why you got bad service/a lack of interest from UK suppliers.
          I doubt there are many setups left in the UK that can afford to spend time dealing with individuals or consider to crank up their equipment for tiddly orders.
          It’s a lot easier to produce one offs or small runs when you don’t give a crap about dumping any waste products, labour is cheap, have the potential to make some extra cash by replacing components with cheaper versions/fakes…

        2. Well, if you were filthy rich you could afford UK suppliers, whose prices are oriented towards providing the type of service their typical customer expects. China is not really that different, it’s just that compared to the typical Chinese person, you are filthy rich.

      2. Want lower prices in the UK and EU? Stop voting for politicians who keep raising taxes! Find some who will work to repeal VAT and other business and job destroying taxes.

        1. ;-)

          Fortunately, the Chinese are generally sensible enough to grossly reduce the item value that they put on the shipping documents, so you don’t get stung as much for VAT and import duty. I once inquired about a bigger laser cutter from China, and they volunteered to put just 1/3rd of the actual item value!

          Why I should get penalised for buy something from abroad that isn’t even available in the UK, beats me. Just a protection racket.

        2. Universal healthcare and social security ain’t free.
          You can only complain about it not being flexible enough, but then shady accountants will just abuse it.

          So it is big-time greedy companies that has ruined it for small-time honest ones.

    1. yeah, I was waiting for the part where the evil Chinese ripped the poor guy off and why they should never be trusted, like almost every other article you read about China in the tech media.

      Also the guy forgot to specify the overall width of the object in the plan view of his drawing, so there is no way they can successfully produce what he is looking for without asking for this information.

      1. he also didn’t specify units, feet, inches or m, cm, mm? asking for a spinal tap stonehenge situation there. asking them to draw a picture of the picture you sent is not enough, as any oversights you sent will be replicated and likely overlooked in review of the returning picture. If you’re working on a project for months the scale and details that seem obvious to you, are entirely unknowns to a 3rd party, especially one separated by thousands of miles, 12 time zones and a language barrier. assumptions are the mother of fuckups.

  2. Would it have been easier to just get a stand heat sink,. and compound that to a back al wall?

    As in:
    Load => Heat sink => Al block on back

    genuine question, I don’t know the answer.

    1. It would work, but it would have poorer dissipation (if you bolt the two together) or poorer environmental protection (if you cut a hole in the back plate for the part). It also doesn’t look as nice. :)

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.