Complete beginner – Making retrofit housing for audio connectors?

[pardonpardon]

Dear CADTutor,

 

I have a question that may seem idiotic. I am mostly a stranger to the world of CAD. I'd like to know whether my idea is feasible at all.

I would like to design, and 3D print my own housing for audio connectors, such as 3.5 jacks. Basically, parts that would replace the usual housing (made of metal usually).

These parts have a screw that attach it to the plug copper part inside the connectors to which the wires are soldered. Would it be difficult to design a screw thread that would perfectly screw onto existing jack plug copper parts?

 

Here's a picture to make it clearer: https://imgur.com/C8aX9lo

I would like to redesign from scratch the silvery metallic part.

 

I hope my question is clear enough!

Thanks in advance for you answers,

[Berzerker]

Welcome pardonpardon. You can design anything you want in Autocad and yes you can export it as a STL and 3D print it.

3 hours ago, pardonpardon said:

I have a question that may seem idiotic. I am mostly a stranger to the world of CAD. I'd like to know whether my idea is feasible at all.

What is your level of experience with it?

Although I've worked around it since the 90's I still consider myself a beginner.

Edited November 6, 2020 by Berzerker

[pardonpardon]

Well. I know the gist of how CAD works. I'm not looking to do extremely complex shapes. Just have a working CAD model of a screw that would fit a jack plug, and then elaborate around it by drawing various shape and adding various beveled motif for instance!

 

1 hour ago, Berzerker said:

Although I've worked around it since the 90's I still consider myself a beginner.

 

You just scared me a lot! My intent is to make custom design for headphones' cables parts, such as the housing of the jack plug, housing of the MMCX plug, Y-splitter and chin slider. Then have a injection mold printed and cast them in Jesmonite so I can screw them onto existing electronic parts.

Does that seem too far off? I'd be willing to pay for someone with experience to design the screw parts, and then learn enough just to be able to translate my drawings to CAD for instance.

[lrm]

The primary challenge I think you face in 3D printing the part you describe is how well small threads can be printed with the 3D printer you will be using. In addition, determining a feasible wall thickness  for the threaded portion of the object will take some experimentation.

 

Check out this link for some tips on 3D printing threads.

[pardonpardon]

I'll be ordering from a website I usually use for 3D printing services (3Dhub). They also do CNC machining and propotyping and have an extremely wide choice of material, with lots of options, down to the layer height and infill options. They usually work with companies that uses last-gen 3D printers. I got metal parts printed with them that turned out amazingly well for a very low price compared to what I could find in my country (central europe).

 

Thanks for the link, I'll look into it!

[Berzerker]

I worked with 2D and have just recently started working in 3D. Why not just tap the parts you want threads in If I'm understanding the question.

[pardonpardon]

What do you mean by tap the parts?

 

2 hours ago, lrm said:

Check out this link for some tips on 3D printing threads.

 

So, what I gathered from reading this is, I need to come up with an extremely precise measurement of the thread that's on the jack connector in order to draw a thread in CAD. Are these kind of measurements obtainable at all?

[Berzerker]

Do you have a pic of what it looks like ? Is it metric, standard, machine screw, self tapping, coarse or fine thread... etc.

Once you know what kind it is you pull a search for a chart on it like:

ANSI

https://www.engineersedge.com/thread_strength/internal_screw_threads_chart.htm

Metric

https://amesweb.info/Screws/metric-external-thread-dimensions-chart.aspx

A set of thread pitch gauges wouldn't hurt

Are you wanting to 3D print a screw ?

You can buy plastic screws, bolts and nuts

https://us.misumi-ec.com/vona2/mech_screw/M3301000000/M3301160000/?listDisplay=mc-photo&msclkid=8b6f01a7321712d305105e02a6f30dab&utm_source=bing&utm_medium=cpc&utm_campaign=FA - Bolts%2FFasteners%2FScrews&utm_term=%2Bplastic %2Bscrews&utm_content=Screws - Plastic

Edited November 6, 2020 by Berzerker

[lrm]

@pardonpardon

A tap is used to cut a female thread and a die to cut a male thread.  The threads are usually specified via an ANSI or metric (ISO) standard that classifies the thread with a nominal size of the thread diameter and number of threads per in.  For example, a 1/4- 20 UNC thread means that the thread has a nominal diameter of 0.25" with 20 threads/inch and is of the Unified National Coarse configuration.  ISO threads will have a designation like M8 plus a thread count.  

 

I agree with @Berzerker that you should use a tap to make the thread.  Therefore you will 3D print the part with a simple cylindrical hole with a diameter less than the nominal size of the thread.  The tap will cut away some of the material giving you a nice clean thread.  You can search the web for what size hole to drill (3D print) for a specific thread size.

 

I suggest you go to the fasteners aisle at a home center like Home Depot or a hardware store.  They usually have samples of various thread size that you can use .  Take the metal housing and find out its thread size.  

 

 

[pardonpardon]

Both your reponses are greatly appreciated! I feel like this might actually be doable. Here's an example of the innards and housing of a regular 3.5mm jack plug. Don't know if this is clear enough to tell what kind of screws that is.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

There are other type of plugs, namely the Viablue ones, which are extremely high-end and expensive, and don't use a screw like this, but a smaller screw on the side holding the housing so it's easily dismantled. It might actually be easier to design a piece using these plugs rather than the one posted above. I could just design the housing with a threaded hole placed correctly, and use the Viablue innards to screw my housing back onto it. The second screw is used to modify the diameter of the back opening.

 

[Berzerker]

In my quick search I have found no chart for a 3.5 mm jack plug. From what I gather it's up to the manufacturer on what threads they use. I would buy one that can fit what you want to do with it and measure it and find out what threads are on it. I'm sure they will go by some kind of standard. The 3.5 mm is the size of the plug end that goes into the device "If I'm not mistaken" and has nothing to do with the housing size. I'm sure these can be picked up at home depot or other similar store.

[pardonpardon]

I'll order some and try that. Yes, 3.5mm in the size of the tip that gose into your audio in.

[lrm]

If the tip is 3.5 mm (= 0.138 in.) I would estimate from the photo that the thread is about twice as big and that the thread is about 1/4 in. so a 1/4  20 UNC  or UNF might be a good guess.  Again, take the part to a hardware store and see if a 1/20 bolt smoothly screws into the part.

[BIGAL]

Take the part to a nut and bolt supplier they will have what is know as a thread gauge it is all the threads like a swiss army knife so can be matched.

 

Threads, metric various pitch, UNC, UNF, BSF, BSW, trying to remember bicycles BA ? Brass, and so on 1 a have a 5 page paper chart has tapping drill sizes oh yeah goes into "Number drills" not just 64/th's

 

Google "Sutton thread chart" returned like 20 threads and charts.

 

 

 

[jagwinn]

1/4-20 UNC; 1/4-28 UNF