[JorgePantalones]

Hi. Myself experience failure making shells. They cure very uneven. Some parts solid while some parts on the thicker walls of negtive dont cure at all, probably due to the silicone negative i went over to use. Before i used gelatin/kanten and larger forms/cups to mold the negatives in. Now i bought the small size cylinders, i probably should have bought the big ones. What size do you use?

I don't know that the size of the cups will matter as much as balancing the depth of the mold you pour with the width of the cup:
 
I've been curing mine on a turntable with the majority of light coming from the bottom of the mold up.  My first two tries had a hole in the indentation between the bit that sticks into the "triangular fossa" and the part that dives down into the ear canal.  I couldn't seem to get enough light in there until I lowered the volume of the mold 5mm (1/4") and then everything came out great.  
 
As a bonus, in my case, the lowered depth of the mold made the bottom of the cast (end of the ear canal) shallower than the sides.  This cured the ear canal a little thicker and deeper which has been better for seating the speaker tubes.

 

[Pete64]

Well, the cylinder i use is 37,5 mm id and 35 mm high. The saying that you cut your mould doesnt really give a figure of how thick your bottom of mould is? The negatives i did before was 49 mm d in bottom and 45 mm on top. But all the time using different acrylics the longest curing time using my 36 w nail lamp was about 2 mins. Longer than that produce a solid rock I also rotate my mould while curing. I also think it could be different acrylics behavure. The acrylic i use now is from mcear.de. I tried also Lisa Pavelkas gloss, but that gave the worst result ever. Best result was from one i ordered on aliexpress. It cured about 30-45 sec and made a real nice shell even it was the first ones i did.

 

[userfault]

  Thanks for your advice! I've bought some and it should be arriving Wednesday! My impression creation is decent, and I'm getting a lot better at using the Krystalloid. I'm hoping that by the time my Nice Fit arrives from China, I'll be ready and able to make quality shells with them! I'll write up a post detailing what I have learned, what has worked, and what hasn't. Unfortunately the list of failures and problems will be much longer than the list of successes :/ On the plus side, I've learned a lot regarding successful shellmaking and I'm getting better with time. Thanks again for all the advice and the wisdom encompassed in this thread. I really appreciate it guys!

Hi guys, long time lurker here(well about two years on and off). I work in the hearing aid industry and got the answers of some of your questions, but I noticed that you had those all figured out yourselves as I go on reading. Though I wanted to give you some info about waxing the impressions before making negatives. The wax we use in the company is Dreve's paraffin wax similar to those bead looking in the link: https://www.alibaba.com/product-detail/paraffin-wax-granules-wholesale-paraffin-candle_60433777628.html
 
And we use the red wax you are referring for filling the gaps(like the ones you have after you remove the cotton plug and have the threads' mark on the impression). I know that there is no right or wrong in this subject as long as it does the job for you. Just wanted to let you know about our usage. 
 
Also I recall that somebody asked about little presure pot somewhere back in the thread for making soft silicone moulds. Soundlink has this little pot that seems to be enough for the job. I didn't use it or know anyone using it but stumbled across the pot and wanted to help if someone is still looking for something like this. http://www.soundlink.cn/productType/13/118 
 
And I have seen that some of you have been looking for a good cheap cable. I have stumbled across this one on aliexpress and It has the best p/p ratio in my opinion. As far as I can see it is the same cable Ultimate Ears used until couple of years ago but with MMCX socket. https://www.aliexpress.com/item/VT-Audio-Cable-Silver-Plated-Cable-For-VT-6-1-Earphone-Upgrade-Cable-With-MMCX-For/32748790564.html?spm=2114.13010208.99999999.337.P7qK8t
 
I also have a big universal shell modelled for my usage, I print it with a professional printer without any problems but I'm not sure if it can be 3d printed with abs systems, even If it is usable I will not be able to know the settings. If anyone is interested just PM me and I will send them to you via email. 

 

[userfault]

I don't think it will be very useful for anyone in DIY thread actually, since we use digital process in the shell making and the whole system cost around 100k-150k euros. But @MuZo2 asked me in PM and I wanted to let anyone know. So the quick review of our shell making steps are like this:
1. Get the physical impression of the ear.
2. Trim the really excess parts, like the impression passing even the outer ear. We don't do much of trimming and smoothing before scanning just because it is too easy to smooth and trim in the software, it is matter of a choice actually.
3. Scan the impression in a 3d ear impression scanner.
4. Model the shell with the shell modelling software. 
5. Use another software for slicing the output file, and send it to the printer. 
6. Clean the mould after printing with isopropyl alcohol(Over %99 purity). And let it dry.
7. After cure with nitro gas, UV curing machine. 
8. Smooth the mould with dremel tool if you think it's necessary.
9. Clean the dust with alcohol again.Let it dry.
10. Dip in lacquer and final cure. 
 
Edit:
 
While I was messaging with @MuZo2 another thing that can be useful for you fellow DIYers popped into my mind. There is an app called 123dCatch for android(Don't know if it has IOS version as well.too lazy to check now). It is a 3d scanner using your mobile phone's camera. A bit tricky to use it but it gives good results imo. Just do not forget putting a newspaper or a magazine under the object you are scanning. The app is using the letters in papers to locate the coordinates as to my knowledge.
 
I have seen couple of people in the thread are working with CAD files and making shells, with this one you can make your CAD designs custom maybe. I am not experienced in whole CAD area so I don't know if it will be easy or not but I guess a CAD experienced headfi'er can do it.

 

[omgflyingbanana]

Hey guys, check out my ER4 clone for $43!
 
Album

Parts List:

Litz wire x10: ¥3

Shell: ¥39.90

Putty: ¥17.50 (note: you could buy this from Amazon for ~$1 more)

Dampers x2: ¥14

ED-29689 BA x2: ¥56

MMCX female connector x2: ¥11 (note: this is kind of pricey, relatively speaking. You can get 4 for $1 on Aliexpress w/ free shipping, or find cheaper listings on TaoBao)

MMCX cable: $10 (note: purchased a while ago from Aliexpress rather than TaoBao, price has since risen. There are definitely less expensive cables on TaoBao with comparable quality, but since I already had a cable I decided not to buy one).

Epoxy: ?? (already had)

Total (excluding shipping): ~$30 Shipping: ¥90 (~$13) Total (with shipping): $43

Notes

As you may have noticed, this isn't a "true clone" of the ER4 since the filter is red rather than green and there is no resistor. I decided to omit the resistor to simplify things and to give the low-end a bit of a boost, but adding two 18 ohm surface resistors shouldn't cost more than $2. I went with red filters since I like my sound sig to be on the warm side; however the green filters have a fantastic neutral sound and I highly recommend going with those.

I decided to go with the shells without screws because I bought some shells with screws before and I did not like them at all. First of all, I believe the seller sent me the wrong screws because they refused to screw all the way, even with the correct screwdriver, making the shells loose. Secondly, the shells without screws seemed to feel a bit thicker and more durable in general. Finally, I thought epoxying the shells together would make the IEM more durable instead of a single screw applying pressure in a single area.

I decided to use putty to hold and seal the armature instead of epoxy/foam/tubing. I didn't use tubing because the internal opening of the Shure shell's nozzle was really small and angled, and it didn't look like the tubing would seal well to it. I didn't use epoxy because there was some sort of shield outside of the nozzle opening (see album) which created gaps too big to be filled with epoxy without the possibility of epoxy dripping into the nozzle. Foam was an option, but it requires constant pressure to seal well in the shield thing. Unlike the previous GK's used in a previous Shure build, the ED-29689's are much smaller and do not fit snugly into the shell. So I decided to use putty for the build, however I am worried about the armature shifting around and factors like temperature affecting it.

Some thoughts on using TaoBao: it is a bit of a process, I definitely recommend doing your research on how to effectively navigate and use it before jumping in OR using a reputable seller. Oddly enough, the subreddit /r/FashionReps has helped me enormously due to their expert knowledge in TaoBao. Basically you order your parts to be shipped to a consolidate warehouse and then the warehouse ships it to you. What makes this difficult is that there are many different sellers and they all only speak Chinese, and the entire website is in Chinese as well. I'd like to personally thank Google Translate for making this possible.

Thanks for reading! Hopefully this will be helpful

 

[Shilohsjustice]

Hello all!!!

I played around with some Zebra Wood today and decided to make it an official CIEM. Here is a couple pics!!!!

 

[Lightsword]

Well, the cylinder i use is 37,5 mm id and 35 mm high. The saying that you cut your mould doesnt really give a figure of how thick your bottom of mould is? The negatives i did before was 49 mm d in bottom and 45 mm on top. But all the time using different acrylics the longest curing time using my 36 w nail lamp was about 2 mins. Longer than that produce a solid rock I also rotate my mould while curing. I also think it could be different acrylics behavure. The acrylic i use now is from mcear.de. I tried also Lisa Pavelkas gloss, but that gave the worst result ever. Best result was from one i ordered on aliexpress. It cured about 30-45 sec and made a real nice shell even it was the first ones i did.

Hi Pete,
 
Which acrylics did you get from aliexpress? I've actually got some Nice Fit on order myself and I'd love to hear what you used, and what worked well for you. I've so far been unable to create a successful shells even when going up to 8-12 minutes of cure time. To be fair, I've only tried some Magic Glos and an inexpensive DLP cure resin. The Magic Glos hasn't yet produced anything resembling a quality shell, and I've gotten only one kinda sorta rough shell out of the DLP resin when I was using it.

 

[Pete64]

This is the resin from Alievpress. I have not find any other that works for making shells. With 36w naillamp i cure this for about 30 sec and after 15 sec and checking each time https://m.aliexpress.com/item/1000000556087.html total cure time is typical about 45 - 60 sec, then pour out the excess and cure for 1 min and finally cure for 1 min in glycerin. I dont now how people succeed with Magic gloss? For me it either didnt cure enough or it was to thick.

 

[piotrus-g]

Hello all!!!

I played around with some Zebra Wood today and decided to make it an official CIEM. Here is a couple pics!!!!

And... now you're at cIEM industry quality, congarts! So when are you starting a company? 

 

 

[MuZo2]

Are there discounts for thread members

 

[Shilohsjustice]

And... now you're at cIEM industry quality, congarts! So when are you starting a company?   

I contacted a few local IEM companies a while ago to see if they were hiring, Alien Ears, Inearz, CTM, but nobody was interested in hiring anyone at the time, lol.

 

[Shilohsjustice]

I got some play time in today and made a set of universals, I was playing around with black ink and made some smoke shells, I used zebra wood for the faceplate, it's amazing what you can do when the house is quiet.







And this is the mess I created doing them, lol.....

 

[Squirg]

I got some play time in today and made a set of universals, I was playing around with black ink and made some smoke shells, I used zebra wood for the faceplate, it's amazing what you can do when the house is quiet.







And this is the mess I created doing them, lol.....

Shiloh, you are the Man!  I'm still not getting that glass-like shine without using Lack3.  What are you using for polishing/buffing?  
 
Top notch!!!

 

[Shilohsjustice]

Shiloh, you are the Man!  I'm still not getting that glass-like shine without using Lack3.  What are you using for polishing/buffing?  

Top notch!!!

Thanks for kind words!! The Universals do have a coat of lak3, in experimenting with the shells I found that adding the black colorant makes the shells softer and I've cracked some shells buffing them out earlier. However, I use a buffing arbor and blue or green compound.

 

[Lightsword]

This is the resin from Alievpress. I have not find any other that works for making shells. With 36w naillamp i cure this for about 30 sec and after 15 sec and checking each time https://m.aliexpress.com/item/1000000556087.html total cure time is typical about 45 - 60 sec, then pour out the excess and cure for 1 min and finally cure for 1 min in glycerin. I dont now how people succeed with Magic gloss? For me it either didnt cure enough or it was to thick.

Thanks! That's fantastic and I'll probably order some of that to try soon. I think I found the same stuff on Taobao and tried to order it, but Taobao is harder to ship liquids Internationally. I'll post my results when I'm done with my tests!