1U Modem/Router Assembly Build Log

[kkpatel87]

So this is a bit of a different post...its a network appliance assembly/build log.

 

I am building a small 6U short depth rack for my living room (Using a Hammond Mfg SDC246U17BK...ill detail that build after i finish this applicance). I selected the ARRIS SB8200 for the modem and the UBNT ERLite-3 for the router. I have not seen a widespread solution to rackmount an ARRIS SB8200 (aside from just using a shelf).

 

The only thing i would find was a 3D print: https://www.thingiverse.com/thing:4050856

 

I think the 3d print is a very creative solution but it doesnt solve some of my issues i wanted resolved:

• No more than 1U space used.
• Built in power supply (no external power bricks! (wall worts)).
• Integration of router
• Coax disconnect easily reachable with going deep into rack.

I went my own way and created a 1U plate assembly housing the ARRIS SB8200 modem, Ubiquiti ERLite-3 router, and power supply. I wanted to ensure i got the most use of 1U with the modem status indicators on the front with all the connections (AC input, 75Ω F bulkhead, and 2x CAT6A keystone jacks) on the back. I selected the MeanWell LRS-50-12 for the power supply for both the modem and router. 

 

NOTE: In the future, i might take both PCBs out of the modem and router and put it into a custom 1U short depth chassis but this is an interim solution.

 

Here is a screenshot of the 3d assembly i created with 2 parts, a main plate and a front plate:

 

Both parts are made from 0.063" 5052-H32 aluminum alloy per SAE AMS QQ-A-250/8. The main plate has two flanges formed via bending. The front plate will attach to the main plate via rivets.

 

Here are the router, modem, and power supply laid out on the plate, pre-form:

 

Here is the sheet metal assembly temporarily assembled:

 

I potted #10-32 inserts on the bottom of the modem and router. This way all the units are fastened from the bottom.

 

Here is what i have planned next:

• Temporarily install modem, router, psu, and connectors
• Create wiring harnesses (Coax, 2x ethernet, and power)

I haven't detailed everything so please feel free to ask questions and i will do my best to answer!

[kkpatel87]

Update, I did the coaxial, ethernet and power wiring.

 

The coaxial cable was terminated first. Just basic 75Ω RG6-Q with two compression type connectors on either end. The cable was quickly tone tested for continuity and installed with the correct torque, 20 in-lbs:

 

I created a simple power harness for the included power supply. I used M22759/34-14-X for the AC input and same random 20AWG for the DC output. The harness is wrapped in Tesa tape to support the AC in and DC out wires. The continuity was checked with continuity mode on a multimeter: 

 

I had a 50 ft CAT6a shielded cable so i am using that as my CAT6a stock. I used cable matters tool less RJ45 Cat6a connectors. I tested the ethernet connections for continuity:

 

And lastly, always test your harnesses:

 

The next update should have the final assembly.

[kkpatel87]

Turns out i am not too happy with my intial concept. I am not too happy with the fit so i think i will adjust and add some flanges to attach to a rail.