"Open Alpha" T50 3D printed headphone project from MrSpeakers
Nov 16, 2016 at 6:22 PM Post #61 of 979
Do share printer settings, model, and materials with the class. Please.


Monoprice maker Select v2, modded with Z-brace, glass plate, DIII cooler, bearing upgrades etc.

.2mm resolution

100% infill

PLA

Cura settings that I spent about a week of pure suffering to get

.4mm full Metal hotend (gunna try carbon fiber filament eventually)

Zigzag zag infill at 45%
 
Nov 16, 2016 at 6:48 PM Post #62 of 979
Great stuff Dan, really impressive action on you and your companies part.
 
I've only purchased a pair of alpha pads and a leather band from you guys, but your service was excellent and the product exceeded expectations. Open sourcing the Alpha Dogs cements you in my mind as one of the best small companies I've interacted with in any industry. I'll send potential customers your way any chance I get.
 
Nov 16, 2016 at 7:40 PM Post #63 of 979
   
I have another question before printing: Did you use acetone for the glossy/smooth finish for cups/baffles? Thanks


Whoops, missed this, but yes.  We use an acetone steam process but this is VERY dangerous and can not be done without explosion proof hot plates and ventilation for hazardous/explosive fumes (and yes, we have had one incident, it was scary enough).  Don't do that unless you have real industrial equipment.
 
However, simply soaking a cotton ball and wiping the interior and exterior will help fuse the layers.  Do this after sanding for best results.
 
Dan Clark Audio Make every day a fun day filled with music and friendship! Stay updated on Dan Clark Audio at their sponsor profile on Head-Fi.
 
@funCANS MrSpeakers https://danclarkaudio.com info@danclarkaudio.com
Nov 17, 2016 at 12:38 AM Post #64 of 979
Alright, so I'm completely new to this 3d printing thing, but my college has a 3d printing lab where I just have to email an STL file as well as the infill percentage, shell number, and filament choice, and then they print it. As you said the cups require supports, would tree supports like these created in netfabb work fine? or is there a better system to use? Also, I assume once i create the desired supports, I would just save the cup as a new STL file and submit that. Sorry for these newbie questions but wasn't really sure where else to ask.
 

 
Nov 17, 2016 at 10:53 AM Post #65 of 979
  Alright, so I'm completely new to this 3d printing thing, but my college has a 3d printing lab where I just have to email an STL file as well as the infill percentage, shell number, and filament choice, and then they print it. As you said the cups require supports, would tree supports like these created in netfabb work fine? or is there a better system to use? Also, I assume once i create the desired supports, I would just save the cup as a new STL file and submit that. Sorry for these newbie questions but wasn't really sure where else to ask.
 

That's basically what I did, my university also has a few 3D printers, I went ahead and set it up in person which was better since the lab technician had a couple issues with the provided STL files initially, but was able to figure them out. I'm also completely new to 3D printing, but when I was talking to the tech it sounded like supports are just extra material printed to hold the thing being printed steady and flat. After it's done printing he said they run it through some sort of bath which removes the support so you are just left with the 3D printed object. When initially setting it up, either the printer they have (Mojo 3D printer) doesn't support multiple configurations or the tech did not know how to change it, but the resolution, infill, etc. was just printed from the default settings, but he showed me some samples of other prints and they all looked pretty good. It wasn't that cheap ($8/cubic inch), but I wanted to use ABS instead of PLA so that I would never have to worry about sagging or anything. The left cup should be finished this afternoon, I'll upload a picture later to compare results. Also, the left cup with support came out to about 4.1 cubic inches, which at $8/cubic inch should cost me ~$32.80. It was printed with the concave side of the cup facing up, since he mentioned the side facing up typically prints marginally better, and I figured that it would be better for the inside so everything fits well and the resulting sound isn't impacted.
 
 
We generally used the highest resolution possible on layers.  It takes longer to print, but there is less sanding and prep and the parts are generally easier to work with.  
 
One tip, when you use ABS after you sand you may want to wipe the parts down with acetone, a quick wash will help fuse the filament together and ensure the parts are good and strong.  Let it cure for a day after acetone. Do this outside, of course.  
 
For fill density we usually run with a low density fill to reduce weight and improve the isolation.  Support is essential on the cups, it's not needed for the baffle or ring if you do your orientation correctly.
 

Hey Dan, I'm not sure what the best approach to sanding the printed objects should be before bathing it in acetone, is there a certain grit to start at and then work it down and finish with a finer grit to get a certain smoothness?
 
Thanks again for doing this for the community, it's greatly appreciated! 
 
Nov 17, 2016 at 11:32 AM Post #66 of 979
My buddy did a test print with filament he didn't mind junking. He printed with the open side of the cup facing up.
 

 
 

 
Nov 17, 2016 at 12:41 PM Post #67 of 979
   
Hey Dan, I'm not sure what the best approach to sanding the printed objects should be before bathing it in acetone, is there a certain grit to start at and then work it down and finish with a finer grit to get a certain smoothness?
 
Thanks again for doing this for the community, it's greatly appreciated! 

 
We actually steam the part in acetone vapor but you shouldn't try that unless you have a serious ventilated explosion-proof lab setup.  Just use a medium grit sand paper, like a 300 or 400, to get rid of lines then wipe with acetone.  That's enough to fuse the outer layers of filament, then do a gentle sand if you see any flat or rough spots.  I don't have tips on how to smooth or finish PLA, we never used that for production.
 
Dan Clark Audio Make every day a fun day filled with music and friendship! Stay updated on Dan Clark Audio at their sponsor profile on Head-Fi.
 
@funCANS MrSpeakers https://danclarkaudio.com info@danclarkaudio.com
Nov 17, 2016 at 12:42 PM Post #68 of 979
  My buddy did a test print with filament he didn't mind junking. He printed with the open side of the cup facing up.
 
 
 

 
We always print open side down.  It generates a bit more raft but you're less concerned with aesthetics and finish on the inside of the cup, so generally having support material on the underside will give a better finish on the exterior.
 
Dan Clark Audio Make every day a fun day filled with music and friendship! Stay updated on Dan Clark Audio at their sponsor profile on Head-Fi.
 
@funCANS MrSpeakers https://danclarkaudio.com info@danclarkaudio.com
Nov 17, 2016 at 12:52 PM Post #69 of 979
   
We always print open side down.  It generates a bit more raft but you're less concerned with aesthetics and finish on the inside of the cup, so generally having support material on the underside will give a better finish on the exterior.

also you're going to line it with paxmate on the inside
this stuff is tough to sand, you want to do as little finish work as necessary
i find abs sands well and pla sands poorly, wet sand it, starting at 80 or 100 and ending at 800
i will be doing some tests this weekend with a fake wood filament, it sands and finishes easily
also a thick shell distance i use 1mm gives you room to sand
 
your support structure should look something like this

view is a cutaway, red is shell yellow is infill blue is support
settings are for abs support is 25%
 
Nov 17, 2016 at 3:47 PM Post #70 of 979
For those who want to sand PLA just coat the outside with epoxy. A nice thing layer using a spinge brush. Then you sand it down using 200 grit to smooth it a bit after drying. Repeat for a few layers and you will remove all stritation and gaps and make it silky smooth.


I'm making custom headphones and sanding pla is a pain. Epoxy coats is so much easier.
Here's an example of one of my cups epoxied and sanded.




It's kinda choose your poison, ABS can be difficult to print with compared to pla. However, abs is easier to finish.
 
Nov 17, 2016 at 5:27 PM Post #71 of 979
It's kinda choose your poison, ABS can be difficult to print with compared to pla. However, abs is easier to finish.

abs is poison too
definitely no rights or wrongs with this stuff
whatever works best for your setup
 
for beginners there's a wealth 
of info on the reddit
 
https://www.reddit.com/r/3Dprinting/
 
this is hatchbox wood pla, sanded and finished with tung oil
 

 
Nov 17, 2016 at 5:36 PM Post #72 of 979
For those who want to sand PLA just coat the outside with epoxy. A nice thing layer using a spinge brush. Then you sand it down using 200 grit to smooth it a bit after drying. Repeat for a few layers and you will remove all stritation and gaps and make it silky smooth.


I wish you would've told me that 6 months ago. I made some fenders for a PWD car out of PLA. I used a dremel to get it close. Then hand sanded, primed, sanded, primed, over and over. I probably have 2-3 hours on just one fender. It worked and looked good, but I think epoxy would be 10x easier and faster. PLA doesn't sand nice so an epoxy coating would mean less primer, less work, and a harder shell.

 
Nov 17, 2016 at 11:51 PM Post #73 of 979
Sorry to necro this thread, but I am building these on a budget as I am currently a college student. 

I currently have free use (dont even have to pay for material) for ABS or PLA 3D printing, I got some old t20RPs for $20, and have a good cable lying around.  I have 2 questions:

1 Will PLA or ABS render better results? I can print both, but I only have 20 hrs with the printing machine (lots of demand for free printing), so I might not be able to print 2 full sets.
 
2 What are alternatives for the connector? I already have paxmate and dynamat, so this project looks like it will total ~$30 (have to buy cotton and the 3.5mm connector and paint), and buying the connectors from mr speakers is ~$25 shipping to japan(+$12 for the 2 connectors).  I dont really want to buy these connectors at this price. Will anything else fit in the design? If not I am just going to directly solder the wire to the driver.

I couldnt reserve the printer until December 7th, so take time with the replies(and I only need to decide a material by this date or get the cad file before).

I can do work in cad, and make custom cables, and have worked with ABS printing in the past, so assume difficulty of the task isn't important. I also have access to a wide variety of tools as I am working part-time as a mechanic, so soldering tricky connectors wont be a problem.

 
 
Nov 18, 2016 at 2:36 AM Post #74 of 979
Sorry to necro this thread, but I am building these on a budget as I am currently a college student. 


I currently have free use (dont even have to pay for material) for ABS or PLA 3D printing, I got some old t20RPs for $20, and have a good cable lying around.  I have 2 questions:


1 Will PLA or ABS render better results? I can print both, but I only have 20 hrs with the printing machine (lots of demand for free printing), so I might not be able to print 2 full sets.
 

2 What are alternatives for the connector? I already have paxmate and dynamat, so this project looks like it will total ~$30 (have to buy cotton and the 3.5mm connector and paint), and buying the connectors from mr speakers is ~$25 shipping to japan(+$12 for the 2 connectors).  I dont really want to buy these connectors at this price. Will anything else fit in the design? If not I am just going to directly solder the wire to the driver.


I couldnt reserve the printer until December 7th, so take time with the replies(and I only need to decide a material by this date or get the cad file before).


I can do work in cad, and make custom cables, and have worked with ABS printing in the past, so assume difficulty of the task isn't important. I also have access to a wide variety of tools as I am working part-time as a mechanic, so soldering tricky connectors wont be a problem.


 


1. Given a straight up choice, go ABS. You'll get a better finish & it's a little more durable. Plus PLA will melt if you accidentally leave these in a hot car.

2. If you're on a very tight budget, hard wire them straight to the driver. But...you need to modify the opening before you print it. A nice fit around the cord is necessary to ensure proper sound. You probably still aren't going to get a good enough fit and will need to epoxy the gaps anyway. That's the nature of 3D printing.

Lastly, if you do have a little money, spend it on pads before connectors. I don't know what your T20's have on them, but the pads are going to make a huge difference on sound.
 
Nov 18, 2016 at 10:43 AM Post #75 of 979
Kk ABS it is....

I have a few different pads I will try out... And if I really like how they turn out, ill probably rebuy whatever pads I leave on them... I decided that I would go with a 2.5mm connector, I can get two male and females for 5 bringing this whole test project to $35. Im hoping that they turn out well and I won't break the bank trying.

Just gotta edit the file to make the hole smaller
 

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