DIY PC Sockets

DIY PC Sockets

by Clinton Yiu

The process of making DIY sockets is very simple. My experience applies to the base type with four pins inline .... (2G11 base) and this methodology can be applied to others as well.

THE CONNECTION:

The female crimp terminals that I use have several codes on the package but this one looks more like a product code then anything else, MLXTW9041. These are made of a thin gauge metal plate formed into a cylinder at one end and a wire crimp base at the other. Since the cylinder is not a continuous tube it has a bit of spring that allows for a tight fit around the light pins. Cut off the wire crimp end to reduce the length of the socket.

Now place these modified terminals onto the pins on your CF lights then solder your four conductor wire onto each individual terminal. Becareful not to use too much solder and fuse the pin and the socket together! Also cut and trim the wires to fit as neatly as possible to reduce the overal size of the rubber socket. The pins and terminals will project about 3/8 of an inch from the lamp base.

!!! Make sure you don't turn the pins on the lamp base. Doing so can break the lamp filament inside!

TERMINAL PULL OUT:

Some people expressed concerns of pulling the terminals out of the rubber socket. Well this is very unlikely for a couple of reasons.

1) The rubber compound I am using bonds very well. It is called PMC-780 by Smooth-On (tel: 908-647-5800) and is a two part compound which achieves a durometer of 80 shores (a hardness index). The terminals won't detach very easily.

2) The soldered wire and the terminal itself has prongs that project away from the terminal's side. This anchors the terminal within the socket. So there is no way the terminal anchorage can not with stand any pullout friction between the light pins and itself.

CASTING THE SOCKET:

The main reason I chose the 2G11 base is because of its clean shape. A simple mold can be made with cardboard wrapped around the base of the lamp. You only need a strip of board about 1.25" wide and 4.5" long to make this inexpensive form. Tape the strip around the lamp base.

The long sides of the form will tend to bow out due to the oblong shape of the lamp base. Simply fold a 1/2" x 1" piece of cardboard and tape one to each side. The spring in the fold will push the form to a near perfect shape. Another way to resolve this bow is to lightly clamp the form with a wooden vice.

With a terminal projection of 3/8" the final socket should cover this by at least 1/4".

Note that the above socket will have a flush outer edge when compared to the lamp base so it really isn't water proof. You can make it better by first wrapping an EPDM membrane to form a 1/8" thick band at about 3/8" from the base of the lamp and then wrap the cardboard form around this band. This will creat a lip to the socket.

DETAILS DETAILS DETAILS:

Now you are ready to pour the rubber stuff... But before you do so you have to make sure you can strip the cardboard form and remove the lamp from the socket for future replacement. The most cost effective form release is any light oil. Baby oil is the best that I can think of.

Wipe a little oil on the lamp pins, base, the inside of the terminals and inside of the cardboard form. Make sure you don't use too much oil or the rubber won't cure near the contacted surfaces.

If you want to be meticulous (anal?) then cut a piece of mylar (drafting mylar is cheap) in the shape of the lamp base and holes for the connection pins. This will provide a clean barrier between the socket and the lamp.

Now follow the rubber compound manufacturers instructions and make your socket!

FINAL NOTES:

It is really for the insane DIY'er to try such a thing. If you are only making one or two sockets it may be difficult to justify the bottomline. In my case I am making about two dozen for all my tanks and fellow hobbyists so the final cost for each socket will be about $3.00 cdn (not considering my time costs of course-cheap slave labour here).

There are of course alternative materials and methods to achieve the same results. This is the best DIY manufacturing solution I have come up with after many months of tinkering with the process in my mind. (I am a bit slow...sometimes ;) .) Am I entitled to intellectual property rights here???

FINAL FINAL NOTES ON SAFETY !!!:

Hey you are dealing with 600 volts here with these compact fluorescent lamps! This can probably kill you. The moist environment we are placing these lamps in doesn't help the situation either. It is a good thing the lamps run warmer than the air otherwise water will condense and short out the whole thing including yourself.

If you are not comfortable with DIY items don't even think about it. Your safety is worth more than a $30 socket.

The experience I have just shared with you is for information only. I am not a certified lighting design professional and I am not well versed with any electrical codes. Do the above at your own risk!

And let me know how it goes... ;)

Can I get paid for this?

Clint

Aqualink Member