[axtran]

My friend agreed to help me with paint! White Nylon "Open Alpha" Cups printed by Shapeways -- first is black primer, then a coat in metallic silver (not shown), finished with Galaxy Blue colorshift paint. Still needs the final clear coat layer and polishing to get it really shiny (like glass). The color changes between a deep blue to a deep red-purple. Can't wait until I get the cups back and dismantle a T40RP MK3 to finish my headphones!

 

[PeterJensen]

My friend agreed to help me with paint! White Nylon "Open Alpha" Cups printed by Shapeways -- first is black primer, then a coat in metallic silver (not shown), finished with Galaxy Blue colorshift paint. Still needs the final clear coat layer and polishing to get it really shiny (like glass). The color changes between a deep blue to a deep red-purple. Can't wait until I get the cups back and dismantle a T40RP MK3 to finish my headphones!

They look really good, with a high gloss shine they should really shine... Do post pictures of your final build and comment on the sound. I strongly recommend getting some Alpha pads as they sound great. If you havent heard Alpha Dogs before but only listened to stock Fostex, you will be surprised with how good they can sound....

 

[Arty McGhee]

dang those look nice!

 

[axtran]

They look really good, with a high gloss shine they should really shine... Do post pictures of your final build and comment on the sound. I strongly recommend getting some Alpha pads as they sound great. If you havent heard Alpha Dogs before but only listened to stock Fostex, you will be surprised with how good they can sound....

I actually own a pair of Alpha Primes (one of my favorite headphones). I'm thinking of actually using Shure 1540 pads, because I actually love the pairing with the Fostex driver. I bought some felt today to fill in the MrSpeakers baffles (facing the ear). I'm wondering what adhesive to use, I might just use 3M Super 90.

dang those look nice!

Thanks!! I love the paint. It really is "Galactic!"

 

[Balazar]

I'm a fist time poster, but long time lurker. This thread has got me very excited! Thank you MrSpeakers! I am a 3D printing enthusiast with quite a bit of experience.

I would like to point out that MrSpeakers has laid out some important details that may be overlooked as far as the printing goes.

It would appear that the parts are designed to be printed the way that he shows in the pictures of the build plates in his post. FDM 3D printed parts can delaminate (splitting across the layers). It's a weakness that can be problematic at times. If you print the parts as he shows in his build plate pictures the layering will be stronger and less prone to cracking or separating. Also when you change the orientation of the part, it changes how the infill is constructed inside the part. I'm not sure if it will have much of an acoustic effect, but it is something that would be fun to play with. Different exterior wall thicknesses, infill percentages and infill patters (honeycomb comes to mind) could all play a role in the sound or at least isolation.

The material and printer setting make a huge difference. A well calibrated printer will have much better layer bonding. Temp, extrusion speed, and print speed all play a large role in object rigidity. It is easier to make a lower resolution object strong than a high res one. I'm not saying that it can't be done, but if you are new to the game it's easier to get a 0.4mm layer height print with a 0.5mm extruder nozzle at a lower print speed to come out accurately with good bonding, than it is to get an extremely low layer height print with a tiny nozzle and high print speed. If you are using a professional print service you probably won't have to worry too much about that. They are paid to have well dialed in machines that make good parts consistently. I know it seems a lot easier to finish a high res piece, but I'll get to that too.

ABS is good stuff for several reasons. It's strong. It is easy to get the layers to bond well. Small scraps can be dissolved into a little acetone and that solution can be wiped onto a cool print bed to make the print stick better and not curl up. Hairspray on the build plate is another good trick. Curling can be conquered and there are many ways to combat it (skirts and walls). ABS can also be made much stronger by applying some acetone to the surface of the part after it is printed and cool. Acetone is a very good solvent for ABS. Brushing it on with a cotton ball will basically melt the the surface layers together. It makes the part MUCH stronger and smooths out the ridges making it much easier to finish. It's a simple process that is easy to control. It's difficult to add too much. In fact some people finish objects by placing them on some kind of stand in a jar or bowl and just pour acetone over them. (outdoors or in a well ventilated area) After a few pours you have a nice smooth glossy object that is LEAGUES stronger than it was fresh off the build plate. MrSpeakers suggests ABS finished with acetone in his post.

If anyone needs printing help, I would be glad to give advice. reprap.org also has a good forum as well as thingiverse.com.

I have a few questions:

1. I don't see a PDF link anywhere. Maybe I don't have enough posts to see it? Can anyone help me get the PDF mentioned in MrSpeakers post? Please and thank you.

2. Will 3.5mm female jacks work? 2.5mm? What is best? I know this thing is designed for balanced input, but I don't have a balanced amp. Just a Fiio E18 at the moment.

3. Where the heck do i get Akasa Paxmate? I can't find a source. It seems that it is a discontinued item. Is there an equivalent that I can get more easily?

 

[audiolibrarian]

I'm a fist time poster, but long time lurker. This thread has got me very excited! Thank you MrSpeakers! I am a 3D printing enthusiast with quite a bit of experience.
2. Will 3.5mm female jacks work? 2.5mm? What is best? I know this thing is designed for balanced input, but I don't have a balanced amp. Just a Fiio E18 at the moment.

If you don't feel like making sure the plug openings on each cup fit a 3.5mm or 2.5mm jack, then you can just have your cable end in one of those connections. Both -/+ left would combine into 1 and same for the right.

 

[Balazar]

Ok, here is my first contribution to this. I modified the cups to have screw adjustable vents like the primes. The STL's and cad file are here on Thingiverse.

Use an M3 set screw. The vent is 10mm long by 1.27mm wide. the threads before the vent are slightly over 10mm. if you want to close it off entirely I would go with an M3X12 if you want the option of completely open; something a little shorter like M3x8 might be a better choice if you don't want any of the screw sticking out when the vent is all the way open.

 

[PeterJensen]

I have a few questions:

1. I don't see a PDF link anywhere. Maybe I don't have enough posts to see it? Can anyone help me get the PDF mentioned in MrSpeakers post? Please and thank you.

2. Will 3.5mm female jacks work? 2.5mm? What is best? I know this thing is designed for balanced input, but I don't have a balanced amp. Just a Fiio E18 at the moment.

3. Where the heck do i get Akasa Paxmate? I can't find a source. It seems that it is a discontinued item. Is there an equivalent that I can get more easily?

1. I am not seeing the links anymore either. Maybe an issue that has occured in the new Head-Fi website design? I only have the exploded view downloaded, which I have reposted here: https://www.dropbox.com/s/9s0r7vjzf3valtl/OPENALPHAEXPLODEDVIEW.PDF?dl=0

2. I would use the Hi-Rose connectors as designed by Mr. Speakers. I like how the connectors click on and they seem sturdy and of good quality. It is perfectly fine to use the Hi-Rose connectors for connection on the cups and then just terminate it in a regular 3.5mm jack. Thats what I have done and I am also using them on an unbalanced amp. As written elsewhere in this thread, pin 1 is for positive and pin 2 for ground. Pin 3 and 4 are left open. This would be identical for both balanced and unbalanced cables - as far as I understand it would only be the amp side of the cable that is terminated differently in a balanced plug. If this doesnt make sense the let me know.
You could obviously also modify the CAD files for use with other plugs, but the only purpose I could imagine would be to use it with other style cables, e.g. Hifiman or Audeze style....

3. Its still possible to find Akasa Paxmate Plus in EU, e.g. on amazon.co.uk... However, I would bet that Silverstone foam is very similar and a good substitute. (I do not have experience with it myself as I found Paxmate in Denmark, but all the specs look similar and they are made for the same purpose - noise isolation of PC tower cases). https://www.amazon.com/SilverStone-...e=UTF8&qid=1494488139&sr=8-1&keywords=Paxmate

And thanks for contributing with modifications on the bass ports - looks interesting....

 

[paulmazz]

So I ended up getting my parts printed by a guy on 3D Hubs with a zortrax m200. He was having trouble printing with ABS so we decided to go with Z-HIPS.
Everything came out really well and I'm getting ready to start putting it all together, but I have a few question.

- What have you guys been doing about the screw threads in the cups? Do you just need to force the t50 screws in or have you been tapping new threads?

- What kind of silicone adhesive are people using for the baffle and pad ring? Is the foam gasket the better option?

Thanks for the help

 

[axtran]

I bought the recommended McMaster-Carr self-tapping screws for plastic applications as recommended in the blowout.

 

[paulmazz]

Thanks, I missed that.

 

[Balazar]

I have all of the parts ordered and I'm ready to tackle this. I think I will be using heat set inserts. You can check out this nifty little idea here. I may need to modify the file again to get enough material in the areas that I want to use them. I have used them on 3d printer parts many times and they are awesome. They come in many shapes and sizes too. Lulzbot sells some higher quality ones that grip the plastic really well and you can buy a handful for a few bucks.

 

[axtran]

Thanks, I missed that.

I should have spares, if you want to just buy a few and you're in the US, PM me!

 

[axtran]

I have all of the parts ordered and I'm ready to tackle this. I think I will be using heat set inserts. You can check out this nifty little idea here. I may need to modify the file again to get enough material in the areas that I want to use them. I have used them on 3d printer parts many times and they are awesome. They come in many shapes and sizes too. Lulzbot sells some higher quality ones that grip the plastic really well and you can buy a handful for a few bucks.

These look awesome! Would let you open and close them a lot more than with my solution. I know how I like to tune them though, so it really isn't that bad.

 

[axtran]

Oh, and FYI--I bought Akasa Paxmate in the US here: http://www.performance-pcs.com/