Bad Advertising of Protoplast

Carpal Tunnel Syndrome

In early 2010 I wrote about Carpal Tunnel Syndrome, I gave a picture of the wrist brace and a description of the process of creating it [1].

A few months later I wrote a follow-up about how the wrist brace had helped me, at the time I was anticipating wearing it at night for the rest of my life [2]. But my wrist has continued to improve. Nowadays I never wear the wrist brace and hardly even think of it. I am a little more careful about posture than I was before, but mostly it has no impact on my life. I think this counts as a full recovery.

At the time I was mildly interested in buying some thermo-plastic of that type to make things, but the only source I found was Jaycar which sold 100 grams for $14.95, Jaycar prices have now dropped to $11.50 for 100 grams or $89.50 for a kilo but it’s still expensive [3].


When looking at the sites that link to my blog I saw a site advertising “Protoplast” which is a type of thermo-plastic that can be used for making things [4]. Protoplast have more reasonable prices, E30 ($AU42.75) for a kilo and their web site offers better prices for anyone who purchases 10kg or more (good for hackerspaces etc). As they post no further than Belgium they aren’t an option for me but they do seem to make a good offer, better than Jaycar offers in Australia.

Protoplast is probably a good product, but I think that their advert is misleading. While it is probably possible to make a wrist-brace similar to mine with Protoplast it’s a fact that my wrist brace was not made with it. My wrist brace started out as a flat sheet of plastic which could be formed to the final product without being melted. Converting a packet of plastic granules (as sold by Protoplast or Jaycar) to a sheet to even start work on such a wrist brace would take some work.

To make a sheet of plastic out of beads sold by Jaycar or Protoplast you would ideally completely melt the plastic, if you just softened the plastic then it wouldn’t be as strong as using a pre-made sheet. During the time that I wore the wrist brace I probably repaired it more than 30 times, this wasn’t particularly difficult to do, I poured boiling water over it to soften the part that cracked until it became tacky and then pushed it together again. But the result was significantly weaker than the original due to the difficulty in welding the broken sections together. I ended up cutting some strips from less important parts of the wrist brace (the part nearest to my elbow) to reinforce the weakest part which was between my thumb and fore-finger. That section ended up being about three times thicker than it was originally while also not being as strong as it was originally. I also had difficulty in making it flat so it wasn’t nearly as comfortable as the original version.

It seems rather misleading to include the picture of my wrist brace on a site advertising plastic which wasn’t used to make it and which probably couldn’t be used to make something that looks as good with the same ratio of strength to mass. But with a suitable disclaimer indicating that the user probably can’t get the same result it would be OK to give it as an example of what could be done.

I can imagine someone using a product like Protoplast to make a wrist brace that can hold a mobile phone, that can be worn with a watch, or has other features that aren’t offered by medical staff.

License Issues

The license for my blog doesn’t permit people to just copy pictures, it’s a Creative Commons Attribution-Noncommercial-Share Alike based license [5]. I am interested in supporting companies that make interesting products and anything that can help people with medical issues is also of interest. So I wouldn’t rule out the possibility of a free license for a picture from my blog to be used in the way that they used it (with a link back to the original blog post). But I would want a description that informs readers that it’s not an item made with their product, merely something similar that can be used for inspiration.

4 comments to Bad Advertising of Protoplast

  • Erik Johansson

    You are of course free to relicense your picture, but in the post you are linking you specifically mention CC-by-SA. Since Wikipedia does not allow Non Commercial licensed material, but I might have misunderstood something.

    You said this:
    I unconditionally license the picture for free use by Wikipedia and others under the CC by attribution license. So if anyone thinks that a picture of my hand would improve Wikipedia then they can make the change.

  • Elena

    They also failed to give proper attribution as per the CC-BY license, which makes it more likely that it is a case of “let’s just take this picture of an object made with plastic from a random website; who is ever going to find out?”.

    Unrelately with the license issue, I’m now wondering how hard would it be to print an open frame brace wrist (that doesn’t break under normal usage) using a reprap-class 3d printer.

  • etbe

    Erik: That’s an interesting interpretation. Of course if someone was going to use that the best way would be to upload my picture to wikimedia and link from there.

    Elena: They gave a link to my blog post, so they didn’t seem to be trying to avoid being noticed. They may have interpreted the attribution part of the CC license as being met by linking to my post – which isn’t an unreasonable interpretation IMHO.

    From my experience with a Makerbot Replicator a big problem is in getting the item to stick to the plate. A wrist brace has no flat areas so would need a significant scaffold to make it fit.

    My wrist brace was made by draping a sheet of soft plastic over my arm so it fell into place, that was a fairly quick and easy process (for someone who obviously had a lot of practice) and scanning my arm to make a 3D model would have taken a lot more work.

    If I was going to build a wrist brace I’d start by making a frame out of 1mm copper wire which I would solder together. Then I’d use two layers of plastic to sandwich it. Then it wouldn’t just fall apart when it cracked, the copper reinforcement would keep it together.

  • Elena

    right, I didn’t notice the link back, it is a reasonable way to attribute (it could have been more evident, but that’s nitpicking, and not really relevant in this case).