I have designed a few couplers that attach a microphone to a speaker. They work well enough in PETG, but I have to hold my hand over the connection to make sure it is as good a seal as possible. I would like to be more sure of the seal, but before I spend $40 or more for the TPU for AMS, I would like to know if there is enough give in the material to create a seal if gentle pressure is applied. It doesn’t need to be much since it gives me good results with the PETG. I just know that currently, slight pressure shifts make a minor difference. If there is enough give to the material (if the TPU is a bit like rubber) then it will create a seal. But if it simply bends a bit but wouldn’t make a seal, then the TPU wouldn’t be worth purchasing.
Yeah probably. Give it a try and if it works then it does.
TPU for ams isn’t really all that soft - it’s 68d.
Do you need to use tpu with ams?
If you have a dryer then I’d go for 95a tpu. Then depending on the number of wwlls and infill % you’ll get various squishiness.
Another thing is that tpu 95a is quite cheaper if you get it from aliexpress or maybe even Amazon.
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Hard to say if you should go with traditional tpu (somewhat rigid like jelly shoes) or say ninjaflex. I imagine if we’re dealing with a mic attached to a speaker, you’re trying to isolate the mic? Vibrations will definitely travel through tpu better than ninjaflex or higher durometer material, iirc. Just an fyi tho, ninjaflex you usually have to print deathly slow, and it’s a bit sensitive to heat creep. But the parts it makes are quite spongey.
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Maybe making a silicone gasket would be feasible? Either creating a recess and adding silicone into it or creating a mold and making a custom gasket?
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attach a microphone to a speaker.
I don’t understand. Why does the connection need to be sealed?
Post a picture of what you’re making?
TPU is going to be more compliant than a normal filament, but it’s not likely to give you a completely water-tight seal.
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You definitely don’t want TPU for AMS.
It’s great for items that need to be strong but flex under a large load instead of breaking. It’s not at all soft.
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If you want an extra soft filament that is still easy to print, have a look at Colorfabb Varioshore. I think eSun has something similar since recently.
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I know people use TPU to make custom gaskets for lower temperature purposes in automotive settings and the like, so it definitely does make a very effective seal under the right conditions. Whether it works for your particular situation is going to depend on whether you’ve got enough pressure on the part or whether it’s large enough to lower infill and allow a bit of give. TPU printing is cool because it responds very differently depending on infill and wall thickness. Where a cast urethane would simply give you its shore hardness, you can get a harder material to act much softer with thin walls and low infill.
I’ve been using the Priline 98A stuff - it’s cheap and I’ve had good luck.
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Thank you all. You’re very kind to try to answer my unclear question. I took a couple pictures, but have not yet figured out how to attach them. Perhaps because I am new, I don’t have permissions yet.
Basically, I have a little box that outputs a specific frequency and volume. I made specific adapters that fit the box and have openings custom-made for certain devices with built-in microphones. In order to confirm that the internal microphone is reading the proper volumes, I hook up my calibrator box to the device. For some of them, the recommended method is to use a wide opening and surround it with acoustic putty. This is messy at times and can take a while. In addition, it is not as predictable and repeatable as I would like since slight differences in how it is placed can give different results. Moreover, a few of them wouldn’t work with this method very well and there is no specific method recommended. I like to be more repeatable and precise.
The adapters I designed fit well, but don’t seal as well as I would like. If I cover the whole thing with my hand and push a little, the results are as reliable as the recommended methods, if not more so.
My idea is that if there is a printable material that has a little give, then a smaller amount of gentle pressure would achieve a consistent result. If I can get a consistent result, I can make these adapters for all my co-workers and send them to the manufacturers to see if they would like to use them.
From the answers you guys have provided, it seems that the TPU for AMS isn’t the right result. I could make something with hot glue or silicon, but it would not be something as uniform as I would like to give others, nor would it fit so perfectly in the little box I made.
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If you’re able to wait you can order relatively small amounts of tpu from aliexpress for quite cheap (100 grams is 4 or 6 bucks).
I’ve no experience in creating such press fitted seals so it’s difficult for me to say. Nevertheless tpu is a fun material to have (IMO, but I love that stuff)
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Seriously, having a machine that will print it with relative ease has been such a revelation. Incredibly useful stuff for the kind of things I do.