@fg Thanks, done :)

The 7x15 chain was never delivered to me.... they sent me another one but it will take lot of times to arrive (best estimate mid June)..... To attach the chain i followed this step: 1 - Open one link of the chain (most of them are openable, but some chain have not openable link) https://photos.app.goo.gl/aPL9KNHU5KY2GZnG9 2- Removed one tab (image show what tab remove) https://photos.app.goo.gl/SZhf36hKmWZN3tzr6 3-Drilled a 5mm hole https://photos.app.goo.gl/Pwp4stwpYSgsk536A 4-Use a spare M5 with T-nuts https://photos.app.goo.gl/gRiDEqWxh9abWHep6 5-Secure it to the back of the Y axis https://photos.app.goo.gl/86CgxZdQHFrz8ye98

@fg No, there are 2-3 screw on the side facing mobo, then you can slide the lid and removing it (is kept in place by 4 tabs, you see the cut on the side) . No need to remove the PSU.

I installed both case and ali fan, now is dead silent. MAybe this can help someone: - Watch out for the power converter, they have exposed connector and they short pretty much with everything (i wasted 2 of them), you can fold it with a heat shrink tube, they don't get to hot. Also watch out for polarity. - Fan have 3 pin connector, the yellow cable is for rpm, you can just avoid it. The 40mm fan have a 3 to 2 pin connector, the 60 mm fan have a 3 to 4 pin connector, but the cable that goes from 3 to 4 are only 2, so you can just cut it and use as 3 to 2 connector - The 60mm fan is a bit thick, it doesn't completely fit inside the ali case, but you can just leave the lid a bit open (without screw and by removing 2 metal tabs), the friction will keep it in place. - For the ali i used the RC10 noise adapter, for the case nothing. - I reused all the previous screw, for the 40mm you can use shorter one, but the original also work. Don't tighten too much, the fan plastic shouldn't touch the case, only the rubber feet should. When i came back from holiday i will begin working on the hot end. I also found, on thingiverse, some "adapter" that allow using a classic 40mm fan for the print cooling, this will be a future project.

@dar.flem First i tried with 7x7 mm but was too small, some connector don't pass trough, so i ordered a 10x10 and works, the only things is the curve radius, is R28 (a standard looks like) but a bit to large for this use. The best solution is to use the 7x7 but you have to cut some connector and then reattach them, very impractical. I also ordered this one, is a 7x15 so should have a more close radius and enough space for cable, and maybe the top of every link is openable, but since is china maybe not..... also nobody know when it will arrive....... Edit: 7x7 vs 10x10 comparison

@dar.flem Noise level are 18 dBA for the A4x10, 15 for A4x20 and 20 for A6x25, they are very quiet. Sold at 12-15€ on Amazon. I'm waiting for https://www.amazon.it/dp/B01MQGMOKI to install them. Also fans comes with "Low-Noise Adaptor"it reduce rpm, so noise (but also air flow) https://noctua.at/en/nf-a4x10-flx/specification https://noctua.at/en/nf-a4x20-flx/specification https://noctua.at/en/nf-a6x25-flx/specification For even more silent setup you can use A4x20 on the hot end too, but they are a bit bulkier.

I made something using a 10x10mm self-supporting chain, but only for the Y axis, it doesn't look all that bad, i only used a M5x6 + T nuts at the back of the Y axis frame. Now i'm looking for a chain with a narrow curve (i made some order from china). Some (bad quality) pictures: https://photos.app.goo.gl/9hdzMMuTZNHoh8B27

The PS use a 60mm fan, case a 40mm, hotend 30mm and print cooling are 50mm blower fan. All are 24V. You can pick anything with same size and voltage, but is not easy to find quieter ones. You can also use 12v fan but need to add something to reduce voltage (or having fan in series). Noctua made the most quiet 40 and 60mm fan, but both 12v (i'm planning to add them, since i have it from my previous printer). The best are: Noctua NF-A4x20 FLX, for the case Noctua NF-A6x25 FLX, for the PSU Noctua NF-A4x10 FLX, i think this could be used for the hot end, but you have to print a new support to attach them. Again these are only 5v or 12v fan, if you use them directly on a 24v power supply you will destroy them, and don't use different fan in series :) The blower fan are the hard part, you will find lot of online store claiming to have the most silent one, but they are almost all the same, someone say Sunon make silent blower fan, but i haven't tried one (you can also check here, keep in mind that low Air Flow mean less cooling).