Hey!
I (@carlf from the Kunststoffschmiede) will share with you the process of how we got to our final mould. It took us nearly 9 months and a team of mainly 4 people.
Don’t even think that we were full time on this clamp, but be sure: Product development takes some time…
So here it is:
The way from an idea to a functioning mould.
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In summer of 2017 we finished building the injection machine, and made the first tests. One of these first test was the clothes peg.
We tried an old design from DDR. We replaced the metal spring with a plastic spring, but it didn’t worked out very well. The spring fractured quite often:( So sad…
Nevertheless it was a success, because we learned a lot about plastic, made an undercut injection mould and presented the first try with many other fancy community creations at the DDW’17.
So you develop your own nozzle, for sure the shorter the nozzle the faster you reach it’s temperature, I agree with you that the threaded nozzle is not good, I will try some different setup of the nozzle.
Thank you very much.
I probably won’t make enough of them myself to sell, but I may give them away locally and use them as an example of a useful product that can be made from plastic waste with low-tech equipment.
@andyn You’re alright I don’t think it’s a good/intelligent idea 
Will you sell them locally ?
@adrienluitot
I’m not planning on selling the clamps themselves, just the moulds so people can make their own. I don’t think it really makes sense to sell plastic products in the Bazar, it adds a lot of unnecessary shipping when we should be focusing on tackling plastic waste at a local level. I don’t know if @kunststoffschmiede sell the clamps somewhere, perhaps they do, they would be closer to you than I am.
Woaw @andyn ! This is a very clean work ! And this is not expensive
Will you sell the clamps ?
@andyn
Cool ! I look forward to see them ! Keep me in touch !
No draft angle, just straight sides and a small radius on the corners, but I think you’re right, the part will be much easier to extract with a draft angle, I’m going to try this on the next one, I’ll have to grind a special cutter.
If you have the injection point on the side and are using a car jack to hold it against the nozzle then you are probably getting most of the clamping force out of the jack rather than the toggle clamps. The car jack is a good method, I think more people should use it, but I think most still just thread the moulds on, it’s simple and secure but not as fast, and you really need to split the mould along the sprue line to get the solidified plastic out.
When I have perfected the mould I will put it on the Bazar. I’m not 100% happy with it yet, it still needs a few small tweaks to get it just right.
@anne-barbier oh didnt see it. thanks 
They are so nice !
When will we have them on the bazar ? @andyn @kunststoffschmiede
@sharma-sagar: please, scroll up a little, she made an attachment, and i made a post to a maintained github repo & external forum post
@anne-barbier
When everythin is nice and smooth we are about 30 clamps during one hour. But we are using a car jack to press the mould against the nozzle. That’s a lot faster then threat. and we have less waste because our sprue shorter.
@andyn
Wow! Good Work!
Do you have any daft angel? When the mould gets warm, the clamp is easy to get out.
would be awesome if you could share your fusion file, i am not sure i got it right my CAM operations seem stupid long 10 hours or so.
nice job, did you use the injection and how long does it take to make one ?
g
Ok, here’s my first go at making this mould. Made one small Ooops, set the machine origin in the wrong place on the first half! But not a disaster, was able to recover it. I moved the injection point to where I prefer it, added a gate, and threaded it M10. I haven’t used the toggle clamp system before, I’ll see how it works out. I made the whole mould a bit smaller to save material (kept the same dimensions of the Piranhaclamp obviously).
Now to test it!
Thanks for sharing the design! I’m going to make a mould based your cad files, if it turns out well I might even offer it in the Bazaar so people can make their own Piranhaclamps locally (makes more sense than shipping the actual clamps around the world). If I do, I will of course give you the proper attribution you deserve for coming up with this.
Andy
Good morning
thanks a million kunststoffschmiede for sharing and caring !
I placed the files for further processing in our mold directory (updates/github there). There is also a preview to the Fusion-360 file here.
I’ve modeled the CAM operations so far and from what i see now :
– 25 Euro for 6600 Aluminium
– around 14 hours (+/-5h) machining time (because of the narrow slots with a 2 mm ball end-mill) = 140 Euro (incl. electricity, end-mills, labor)
– 20 Euro Shipping
not sure where to place channel for the plastic entry yet, nor i don’t know this can be done actually with Dave’s default injection/extrusion machine but i will try my best to get it working for both. I know there is a tool to simulate injection molding…. anyone has suggestions ?
thanks,
ps: finally pp got it’s first nice open-source mold
