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Discussion Starter · #1 ·
Anyone else getting fed up with their tweeters falling back into their doors due to broken lugs on the mounting bracket?

An office move a couple of weeks ago set me thinking about this when I discovered a 3D printer lurking in the print room nearest my new desk.

After a bit of research, I spent a couple of hours mocking up the bracket using some free online 3D software - see the image below (so far, I've only completed the side that retains the tweeter itself).

I've no idea if a 3D printout of this part will be strong enough to actually retain the tweeter and its grille - but once I've printed it, I'll let you know.

So - has anyone tried this before?

And - if it works, I'm happy to produce copies (in small numbers...) and/or distribute the output files for others to use...
 

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Discussion Starter · #3 ·
Excellent - what material did you use for your prints?

The printer I have access to is an Ultimaker Original, which I believe uses PLA only.
 

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Excellent - what material did you use for your prints?

The printer I have access to is an Ultimaker Original, which I believe uses PLA only.
I used PLA although I do have some ABS filament for my printer. ABS is a lot more effort though ( higher bed temperatures and higher extruder temps ). Also, the print needs a higher ambient temperature and protection from draughts.

I went through a number of prototypes and part of that process was deliberately breaking the lugs to assess how strong they are - both originally and after I beefed them up a bit. PLA is pretty strong stuff - even with low levels of fill ( I've used between 10% and 20% so far and the one in the car is at 13% IIRC ).

A tip I've learned is that smaller layer sizes improve the surface finish whilst thicker layers increase strength. So I've been printing my prototypes and the one currently in the car at 0.3mm layer height for the additional strength.
 

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I?m an engineering lecturer and we use 3D printing for all sorts of things. If you are handy with 3D CAD it?s so handy for missing parts. Strength is no longer an issue really for ?interior? parts. Print it at 100% strength and you?ll be fine.

Great idea also btw!
 

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Would it be possible to modify the design slightly to fit say an Alpine or Pioneer tweeter behind an original style grille? The factory tweeters sound pretty awful but I've kept them because like the standard factory look.

I know a guy on here has modified his to fit Alpine tweeters but it does require some cutting and hacking. As mentioned in another thread they're not cheap anymore so making a hash of it could be an expensive mistake.
 

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Discussion Starter · #9 ·
Would it be possible to modify the design slightly to fit say an Alpine or Pioneer tweeter behind an original style grille? The factory tweeters sound pretty awful but I've kept them because like the standard factory look.
If you're 3D printing then sure, you could modify the design.

My project has stalled somewhat for a couple of reasons - first, I'm having huge difficulties getting 3D prints to correctly adhere to the printer base plate, meaning the majority of my prints have been unsuccessful. That's really frustrating. And secondly, the design of the tweeter bracket is such that it can't easily be printed in one piece because of the required overhangs, etc. So I need to rework my design in two parts which would then need to be bonded together. I just haven't had the time to pursue this further in the last few weeks, unfortunately.

So - definitely not as easy as 2D printing, that's for sure...
 

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And secondly, the design of the tweeter bracket is such that it can't easily be printed in one piece because of the required overhangs, etc.
In your slicing software, you should be able to specify supports. These are bits of plastic built from the base up to support overhangs. They are broken off once the printing has finished.

They will result in poorer surface quality on the print, but as they are never seen, it's not a major concern ( at least I don't think it is! ).

As to bed plate adhesion :

Even with PLA, set the bed temperature ( if the machine has bed heating ) to at least 60°C. Masking tape also helps with adhesion as well as other methods ( hairspray, pritt stick ). Masking tape is the easiest. The type of masking tape ( in my experience ) makes a difference as well. I tried some very smooth masking tape and it didn't work for me. The rougher ones do.

Take time to set the nozzle height with paper and ensure the bed is absolutely level using the paper technique.

You can also experiment with Brims, rafts and skirts to help with adhesion. I've never bothered with a raft so far.
 

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Discussion Starter · #11 · (Edited)
In your slicing software, you should be able to specify supports. These are bits of plastic built from the base up to support overhangs. They are broken off once the printing has finished.

They will result in poorer surface quality on the print, but as they are never seen, it's not a major concern ( at least I don't think it is! ).

As to bed plate adhesion :

Even with PLA, set the bed temperature ( if the machine has bed heating ) to at least 60°C. Masking tape also helps with adhesion as well as other methods ( hairspray, pritt stick ). Masking tape is the easiest. The type of masking tape ( in my experience ) makes a difference as well. I tried some very smooth masking tape and it didn't work for me. The rougher ones do.

Take time to set the nozzle height with paper and ensure the bed is absolutely level using the paper technique.

You can also experiment with Brims, rafts and skirts to help with adhesion. I've never bothered with a raft so far.
Yes, I'd considered adding supports but given my base model already has the "outer" (lugs for the tweeter) and "inner" (lugs for the cover) sections as separate elements, I figured I'd separate them for printing - which will also give me a larger base area for each element to assist with the adhesion issues I'm getting.

Unfortunately the printer I have doesn't have a heated base plate (it's an Ultimaker Original) and despite using PLA as the substrate it's not sticking. Next steps are as you suggest - replace blue tape; calibration; try Pritt stick, etc... but it's frustrating that this is far from being a plug-and-play system... hey ho...
 

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Hi guys, I would like to fix my tweeter mounts and am looking for these 3d models.
I tried thingiverse but could not find it there.
Can anyone be so kind to upload them somewhere or send them on my e-mail?
Thank you in advance!
 

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A short update - both the speaker bracket and the speaker cover are broken in my car. Pkr sent me his model of the holder and with his help I was able to model a cover replacement and test my 3d prints for the speaker coverI.
Some photos show the progress so far.
Our local shop has a 30% discount on the Hertz DT 24.3 so I have to decide now if I want to model the bracket that would hold the original tweeters or use the one from pkr with a new Hertz tweeters.
951639
951640
951641
 

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I mounted the stuff and so far it looks and functions well. Still not sure about printing with PLA - some say I should use ABS since it is in a car... I have uploaded the models on thingiverse and will add the link when I it is available for download.
I am attaching to stl files that could be used for printing the adapter and the cover.
Apparently I can not upload stl files even if I change the extension of the file to jpg.
 
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