Timon🛠 Profile picture
17 Oct, 22 tweets, 6 min read
Lets play "Which part is cheaper?"
We have two 16-pin USB-C connectors. One costs ~20 cents and the other ~5 cents at QTY 100.

Thread Image
Any idea yet?
The differences are subtle.
There is actually very little telling about "quality" here, just different processes.
Solution in the next post.
The left one with the golden contacts inside is the cheaper part. It is a "SHOU HAN TYPE-C16PIN "

The right part is a "HRO TYPE-C-31-M-12"
The biggest difference is visible here. The wings on the SHOU part are a bit cracked where they folded. This might be because they are folded faster, further or because the metal has a lower breaking point. Its totally fine though, its literally microscopic factures. Image
The HRO part is bonded slightly neater with barley visible gap. The SHOU part has a very slight gap. Again nothing dramatic. Image
As you probably noticed the HRO part has its contacts not fully coated. Not a big deal but it does technically give more attack surface for corrosion over time.
So price is not always as telling about quality as it might seem, SHOU may just have developed a more efficient process
Oh and the SHOU has shorter PCB contacts. Totally ok but actually harder to hand solder, so that might be something to consider if you purchase the parts for your projects.
Ok I thought it would be cool to also look at the mould. This is essentially what forms the connector and plays a big role in how cheap and how reliable the part is.
Here we have the HRO part. We can already see that is a very complex mould, that was certainly not cheap. Image
Other side Image
This looks like at least two pieces or a multipart mould. All these tiny slots are likely pins that retract after the moulded piece has cooled down. Those definitely increase the cost of the tool.
Here is the SHOU part. We can clearly see that its a much less complex mould and my guess this is the true origin of the price difference. Image
Other side. This also seems to be two pieces or multi part mould but a lot less complex feature wise all in all. Image
Ok so thats interesting too. The more expensive HRO part has gold coated copper (as the front pics already suggest). This coating is not super thick, I could scratch if off with my tweezers. The SHOU part though is golden through and through. ImageImage
I don't know much about metallurgy. The only thing I could imagine is gold coated brass, which would certainly make some price difference as well.
So its hard to judge how thick the gold coating actually is on the SHOU part.
If you zoom in and oversaturate the front picture of the HRO part you can see the gold coating quite well. So that we see copper in the front simply says that they coat before they cut the strips. Image
And here the proof that the SHOU part is actually two pieces (the front got damaged in my scratch tests).
The HRO part does in fact seem to be a single mould though, what I thought was a cut off was just the parting line after all. Image
Interestingly the retention clip is quite a bit larger on the SHOU part. Image

• • •

Missing some Tweet in this thread? You can try to force a refresh

Keep Current with Timon🛠

Timon🛠 Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!


Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

More from @timonsku

16 Oct
One of those weird German things that I think are not really well known outside of Europe is the fact that it is very normal that several bombs will be defused in you area, every year. It is so normal that we got a "Kampfmittelräumdienst", a public service to remove bombs. /1
Unlike many countries they have nothing to do with police or military. They are more like (and often working with or part of) the fire department.
WW2 was 80 years ago and we are not even close to having all the bombs removed, its being estimated that about 1/5th has been found
Around ~5500 bombs are being found every year in the whole of Germany. So the chance of you needing to evacuate your home because of a bomb being disposed very close to you is very high and might happen multiples times in your life here.
Read 5 tweets
16 Oct
Ok EEZ Bench Box 3 assembly thread is a go.
Feets are on
PCB also haz 🦶
Read 17 tweets
15 Aug
I created a re-usable 3D printed mould to cast little plant pots from concrete. Here is what went well and what went wrong [Thread] Image
At first I designed it as a 2 part mould in @adskFusion360
You can see more about the initial design here:
The idea was simple, have a big hole on the bottom to pour the concrete in and a few smaller ones to let the air out. Uneven spots on the bottom wouldn't visible and its easy to sand. That was at least the idea. Image
Read 26 tweets
5 Jan
Inspired by watching @ruthgracewong talk again I thought it might be fun to take a look at the Fomu made by @xobs and @mithro and see what went into this seemingly simple tiny product. Please bare in mind I'm no expert at this, just the knowledge I picked up over time.
I will mostly look at the case for now, I think many of you are familiar with PCBA, though I think @xobs might have some interesting hard ships to share from that too.
For example that hard gold can be.. hard :)
The case is a single injection moulded piece of clear plastic and its a pretty nifty one!
Lets first look at these overhangs that hold the Fomu in place. These are normally not possible, if you think about it, so you gotta trick around a bit.
Read 23 tweets
23 Sep 19
All the stuff arrived today. Unfortunately there were issues with the display assembly plastic piece and the backplate.
They were printed in SLS, not exactly the best process for large flat things, so some warping is to be expected. (Thread)
There is also some shrinking which the manufacturer usually accounts for you by making your parts a bit larger.
This has completely failed with Weerg here, they made it so much larger that it is 2mm longer than it should be and the warping is enormous. So the parts are not usable
Again, really shitty part for SLS but it was the fastest option. In hindsight I should have let e-make mill those 2 pieces as well and only print the blocks and face plates.
The overcompensation is really the biggest issue, typical SLS warping would have flattened when fastened.
Read 14 tweets

Did Thread Reader help you today?

Support us! We are indie developers!

This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Too expensive? Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal Become our Patreon

Thank you for your support!

Follow Us on Twitter!