How to repair acrylic earmold?


Not the main topic, but there seem to be people on this thread who know about molds. I have an Oticon Delta 11yo mini acrylic mold that is badly chipped at the hole that allows sound to pass thru- causing feedback. I know the HA technology is older than dirt… What can I use to fill the acrylic in? Btw, I’ve recently returned 3 HA’s to Costco because of mold fitting problems- 5 sets were made by Phonak and Bernafon. I’m afraid to show my face at Costco- lol I give up.


Resound Preza from Costco

If the mold is a hard acrylic type I would be tempted to try an epoxy for a temporary fix. It would be a good idea to try it first on a discarded mold to make sure the epoxy will stick to the acrylic. The article at the link below is one of the better ones I have found on the impression process to make molds.

Earmolds and Hearing Aid Shells: A Tutorial Part 2: Impression-Taking Techniques that Result in Fewer Remakes

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Thanks Sierra, I repaired my acrylic eyeglass frames with a $13 product called the 5 Second Fix- it is a squeeze tube of liquid-plastic that cures with an attached UV light- it is not a glue. I got it at the hardware store. I’m concerned how safe it is touching my skin if applied on my mold.



I am a JBWeld fan. It is an epoxy as mentioned earlier. 2 parts to mix and apply to repair. A toothpick is handy for small repairs.
Just squeeze out enough to do the job.



I think the UV cured glue could work. I have not used it, but have looked into using it. It seems to me that one limitation of it is the depth of the glue that can be cured effectively with the UV. That said I believe UV is now used to cure white fillings in your teeth. I would consider any type of repair temporary, and you should also be watchful of any irritation of the ear canal. Molds are all made from special non allergenic materials. Not sure what epoxy or UV cured glue would be like next to the skin.

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Another way to tackle the problem would be to take an impression of the mould as is.

This would create an exact negative impression of your current mould.

You would then fill this with the usual mould impression material and send this off to have a replacement mould made. You would need to file down the bit where the chip is to make it flush.

With CAD and 3D printing, I’m sure you could just send the moulds off to have replacements made.



Thanks for the suggestions. Send where? As far as I know, Westone only takes impression work from audiologists. Where would I get the little blue or red plastic part the speaker connects with? Thanks…



Lloyd’s can help you.

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The UV material should work fine, back in the early 2000s most manufacturers went form the polymer and monomer plastics to UV. I used to manufacture my own molds and shells and loved the old system but the UV definitely has its advantages. Your biggest issue will be how to grind off and buff the excess of UV material to keep it comfortable. Make sure you clean the area for build up or the UV may not adhere.

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Whoa, how do you make your own molds with a RIC? T/u. And I did call up Lloyd’s. I could send it in and they will duplicate the mold, but I’m going to try the UV plastic 1st. The tube comes with an insanely small nozzle, so I think I can very carefully build up the defective wall of the mold.
Alas, what I really need is a #10 battery HA, with a very small power speaker/receiver for a moderately severe, flat across hearing loss… I have small ears, very sensitive ear canals, the Phonaks came with a HUGE power speaker (it stuck out of my ear canal) and the Bernefons Zerenas were too wide, big for my ears.
Thank you for all the suggestions. I believe us hearing aid wearers have a better collective knowledge than the professionals.

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Are you allergic to the clear shellac nail-gel material that the beauty places use? We use it (the medical grade) for retaining items in acrylic, fixing receivers in place, retaining sport locks and adding to moulds. I haven’t run into any issues with it.

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Where do you buy medical grade? T/u.