[mattmatt]

I'm still not 100% certain ofc and if someone can correct me, please do.

 

[BadgerMcBadger]

I’ve use this and it has worked well. It’s mixed 1:1 by weight, so a kitchen scale is helpful
https://a.co/d/6sqCnPm

As far as poking the shell, I’d avoid that. When you do the initial cure it will still be somewhat flexible. You should be able to eyeball the thickness by looking at the edges of the top of the mold.

My process is usually pour —> initial cure —> cure upside down —> remove from mold —> final cure for several minutes in glycerin to avoid the sticky inhibition layer

how long does it take to cure usually? im debating whether to let it cure overnight or do it in one day
(im guessing it will take less than written on the box because of the small quantity)

 

[tonybuild]

that looks lovely! Are this premade agar or you made it from scratch?

Honestly it not agar
Its 200 ml cold water ,150 ml glycerin , and 1 oz of Clear veggie gelatin (ill show you which brand ).
Mix glycerin with cold water and add clear gelatin , mix it and put in the fridge. Next day just boil it and Again put in the fridge for 12 h . Ones it ready, just Cut the piece from the batch and melt it for you diy ( you know the process) man it work great for me . Dont pour quickly so that you wont make bubbles,

 

[tonybuild]

Did you use my magic sauce recipe from way back in the thread.... Im still using the same colloid from the second successful batch I made. I just keep adding a little water plus some glycols.

I had hard time with it but im gonna post what i use soon. It easy and not expensive

 

[swtnate]

The highest I saw was 200uF back in the day when we used to do reshells. I strongly feel like you are limiting yourself, mainly because you probably read it about floor speakers and IEM designs are completely different.

https://asiustechnologies.com/pages/legacy read up on patents

I was reading this guys stuff. Pretty crazy! Dude invented a second ear drum. That nuts. I also read about this ENT that invented a one way filter that releases sound pressure but doesnt sacrifice isolation. I was mainly just curious if it all actually means something or is it just tweaks around the fringes.

 

[swtnate]

I had hard time with it but im gonna post what i use soon. It easy and not expensive

Agar powder is a bit temperamental. You have to hold it just under boiling while constantly stirring. Depnding in how much agar you added, will kinda dictate how long you will have to stir. But, once it wets out and get completely absorbed, the liquid snaps to clear. and you know its time to cool down.

 

[swtnate]

I had hard time with it but im gonna post what i use soon. It easy and not expensive

BEFORE I figured out this colloid recipe, I used gelatin with glycerine, water, and some added alcohol I believe. The problem I also had was that the negative form would always melt under UV light exposure. If I'm trying to cast an opaque black shell and it needs a solid 5 minutes of curing, that's negative form will be a puddle within that 5 minutes

 

[tonybuild]

BEFORE I figured out this colloid recipe, I used gelatin with glycerine, water, and some added alcohol I believe. The problem I also had was that the negative form would always melt under UV light exposure. If I'm trying to cast an opaque black shell and it needs a solid 5 minutes of curing, that's negative form will be a puddle within that 5 minutes

Actually this one holds up pretty good. don’t know , my like a rubber .May be because I added more glycerin and gelatin that I use its pretty clear.

 

[tonybuild]

this one

 

[tonybuild]

Also , this way it cures faster and even .

 

[swtnate]

Also, I was reading some older audiology white papers/ case studies, describing some standard practices for custom fit hearing aids. When describing the traditional PnP system, the paper stated, “most manufacturers will give the impression(s) .3mm to .6mm of wax build-up, before creating the form that will serve to cast the final shell.”

.6mm ?!? That seems really quite low. The assessment is that those numbers (.3-.6mm) create much less send backs and fit adjustments. I know the our custom IEMs are uniquely different in many aspects but a fully occluded ear is a fully occluded ear. If they can get there with .6‘mm…. I may need to watch some hearing aids being made.

 

[piotrus-g]

Also, I was reading some older audiology white papers/ case studies, describing some standard practices for custom fit hearing aids. When describing the traditional PnP system, the paper stated, “most manufacturers will give the impression(s) .3mm to .6mm of wax build-up, before creating the form that will serve to cast the final shell.”

.6mm ?!? That seems really quite low. The assessment is that those numbers (.3-.6mm) create much less send backs and fit adjustments. I know the our custom IEMs are uniquely different in many aspects but a fully occluded ear is a fully occluded ear. If they can get there with .6‘mm…. I may need to watch some hearing aids being made.

when we were transitioning to 3D we did measurements of the wax coat we were putting on and it came down to around 0.6mm and FYI it cannot be translated 1:1 to 3D printing haha

 

[swtnate]

when we were transitioning to 3D we did measurements of the wax coat we were putting on and it came down to around 0.6mm and FYI it cannot be translated 1:1 to 3D printing haha

Is that .6mm just the wax layer thickness or does it account for the overall increase of the impression. Ie .6mm surrounding all sides would be an increase of 1.2mm. OR is the .6mm you recorded the overall so the wax layer would be 0.3mm? Also, with 3D the build-up is/ can be uniform whereas wax dipping causes more-ish build-up in certain areas opposed to others.

 

[piotrus-g]

Is that .6mm just the wax layer thickness or does it account for the overall increase of the impression. Ie .6mm surrounding all sides would be an increase of 1.2mm. OR is the .6mm you recorded the overall so the wax layer would be 0.3mm? Also, with 3D the build-up is/ can be uniform whereas wax dipping causes more-ish build-up in certain areas opposed to others.

oh boy that was long long time ago I'm gonna say 0.6mm as just wax layer so whole impressions increased by ~1.2mm

 

[swtnate]

oh boy that was long long time ago I'm gonna say 0.6mm as just wax layer so whole impressions increased by ~1.2mm

These doctors were claiming .3mm as being in range for proper fit and I find that a little suspect.