Homebrew WRT54G outdoor enclosure

Last updated 2008:08:01.

You like this project? You have further questions? Send me an email! The address is on the main page at www.2xlc.de.

Outdoor WRT enclosure

FAQ

What is your router used for?

This access point is one of three boxes that I use to "beam the Internet" from my neighbours to my place. The three boxes are setup as WDS repeaters. At the beginning I encountered many problems with WDS. Furthermore there is no line of sight between the three boxes. After a lot of reading and experimenting with different antennas etc. the setup is now in a productive state since more than 1,5 years.

Is your outdoor enclosure PoE enabled?

My homebrew enclosure does not have PoE (Power over Ethernet) support, since the router is not connected to any cabled network. It is used outside to repeat WLAN signals for other access points. Even though adapting my outdoor unit to support PoE is fairly easy.

What is the Ethernet cable within the box used for?

It is possible to open the box (see photos). Therefore I included the Ethernet cable for service purposes.

What is the current uptime of your outdoor router?

More than 1,5 years and still counting... :)

Has your unit survived any extrem weather?

Yes, indeed! We have had less than -20°C outside during the last winter, and the unit worked like a charm. There was no condensed water (neither summer nor winter) within the enclosure at any time. During the last summer we had above +30°C and there were no overheating problems at all.

Why?

The Linksys WRT54G and WRT54GL are nice accesspoints, but some of us need to use them outside, for instance to get neighbours online. "Outside" in my case case means that the WRT should be resistant against direct exposure of sun, rain, snow 24 hours a day, 365 days a year.

How much does the project cost?

I built the entire outdoor enclosure for less than 25 Euros including everything from the actual box up to the required tape. The WRT has a size of approximately 21 cm x 21 cm x 4 cm, therefore this is a minimum requirement for the plastic box. You should also pay attention that the side of the box that the antennas will stick out is a straight line (not bend or something), otherwise you will later on have problems getting the antennas outside.

Partlist

The following parts were used for the project:

Amount	Name	Description	Cost (Euro)	Total
1	Gies Granos plastic box 4.5 Liter	Plastic box for food (30 cm x 22 cm x 9 cm)	6.00	6.00
1	Screwed cable gland Kleinhuis Metric M25 (pack of two, IP65)	Used to get the antennas outside	2.89	2.89
1	Screwed cable gland Kleinhuis Metric M16 (pack of two, IP65)	Used for the power cable	2.49	2.49
1	Tesa extra Power Universal 50 meters	This is some sort of duck-tape used to cover the isolation tape	8.49	8.49
1	Isolation tape	To seal the plastic enclosure	2.49	2.49
1	10 meters of outdoor compatible cable	Two wire copper, well isolated	3.90	3.90
1	Plug 2.5 mm with a length of 14 mm (2.1 mm for WRT54GL)	To "extend" the power supply	0.39	0.39
1	Outlet 2.5 mm (2.1 mm for the WRT54GL)	To "extend" the power supply	0.70	0.70

The following tools are required:

Name	Description
25 mm drill	To drill the holes for the screwed cable glands
16 mm drill	To drill the hole for the screwed cable glands
Soldering iron	For the cabling
Ruler	Used to figure out where to drill the holes... ;-)

Building the enclosure

The first step is to drill the holes for the antennas. You need to draw the exact points on the plastic box. The middle of both antenna plugs on the WRTs are located 14.6 cm apart from each other.

After marking the exakt points you have to drill the 25 mm holes - but be careful, it's plastic! Do not use a high rpm setting on your drill, my holes were drilled with 500 rpm.

The next step is to drill the hole for the 12V power cable, therefore use the 16 mm drill. This hole should be on the side of the plastic box.

Now you have to put the cable glands into the appropriate holes. Before doing that I put a round piece of ducktape around the hole in order to additionally seal the space between the cable glands and the box.

The next step is to solder the plug to the cable. Wrap some isolation tape around the part of the cable that will stick in the cable glands and put the plug through the cable gland afterwards.
Now you can plug the cable into the WRT and put the WRT into the enclosure. I additionally connected a 1 meter RJ45 cable to the accesspoint's switch in order to be able to use it for service tasks.

You should use some plastic or rubber material that ensures that the WRT does not move around in the box. For my project I used some pipe isolation that was left over from some other project.

Then you can put the cap onto the box. The next step is to use the isolation tape to seal the cap and the plastic box by tightly wrapping it around the box and the cap a couple of times.

Afterwards use the ducktape to completely cover the isolation tape (this is to make the entire thing completely waterproof and weather resistant).

Possible problems

Waste heat

Since the box contains 4.5 liters of air the waste heat of around 5 Watts is not a problem in my case. The box gets warm (maybe 20 - 25 degrees Celsius) during the day, but it cools down during night time. A possible extension would be to use metal plates on the inside and outside that are connected with big iron screws to deduce the heat to the outside (might be required for smaller boxes).

Condensed water

Use silica gel (the small packets that come with new harddrives etc.)

Heavy rain

My box is really water-proof - I did several underwater tests in a bath tube. You may additionally protect the enclosure by putting a plastic bag around it in order to keep really bad rain etc. away from it. Due to direct sun exposure the bag should be renewed once in a while.

Pictures