# DIY bulb retainer for H3 HID's



## Cee-dub (Feb 20, 2007)

I set out to install HID's in my Hella Micro DE fog lights, which use a H3 bulb. If you've ever installed
a "drop-in HID kit," you'll know it's not quite that straightforward because the rear end of HID bulbs is
much longer than a standard Halogen bulb. With an H3 bulb, this is especially pronounced because a
standard H3 bulb has essentially no rear end. Here's a side-by-side shot of a standard H3 bulb and my 
H3 HID bulb:

The Micro DE has a spring clip to hold the standard H3 bulb in place. Because of the difference in shape,
this clip didn't have a snowball's chance of being useful with the HID bulb. Here is a picture of the
backside of the Micro DE light, showing the opening through which the bulb passes, and the spring clip
(hanging straight down):

Online searching provided a couple of ideas courtesy of the expedition motorcyclists -- wrapping the HID
bulb in place with mechanic's wire, or severely bastardizing the existing spring clip. Hm... I decided to
make a small bracket to hold the HID bulb in place.
I removed the spring clip (it just pops off). Then I removed the aluminum backing plate from the fog
light housing. It is held in place by three 7mm torx screws (visible in previous picture). This plate has
the square & round pegs which the slots in the base of the H3 bulb locate on.

Then from a piece of thin steel I made a bracket. I drilled two holes in the bracket to pick up on two
of the bolt holes on the aluminum backing plate. The middle section of the bracket presses down on
the flange portion of the HID bulb, pressing it against the backing plate. I just cut & bent bit by bit
until it held the bulb snugly & fit well, then drilled the holes and filed all the sharp edges smooth to
finish. All you need are a strip of steel, tin snips, a small file, and a pair of pliers.

 
 
I was real happy with how things were going, and I tightened the first bracket down on the first bulb. 
I heard this awful cracking noise as the base of the HID bulb crumbled under the clamping force of my 
whizzy bracket. Gotta love that Chinese plastic.









So I modified the design slightly for #2. Instead of completely notching out the middle portion of 
the bracket, I instead bent it over. This way, there would be a flap of steel pressing on the bulb 
instead of just the edge. Also, I notched it up higher and placed a tiny piece of rubber in between 
the bracket and the bulb. This way, when tightened, the rubber just compresses snug instead of the 
bulb disintegrating. http://****************.com/smile/emthup.gif Worked like a dream. Here is Bracket #2 (on the left) beside 
Bracket #1:
 
And the finished product in action:
 
The fruits of my labour! Worth the fuss:









http://****************.com/smile/emthup.gif http://****************.com/smile/emthup.gif (Credit to _kilimats_ for the animation inspiration.)


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## cula (Feb 11, 2010)

*Re: DIY bulb retainer for H3 HID's (Cee-dub)*

Can you please send me a picture of how the boot locks like after you modified? I'm doing the same thing for my bike, but looking to a different kind of clip (retainer), something easier. I'll let you know how things turn out.
Thanks.


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## CaptainQualude (Oct 29, 2008)

*FV-QR*

Aren't you supposed to space the bulb seat so that the tip of the longer bulb is in the same spot as the shorter bulb? The projector was designed for the bulb to be in a certain position or it doesn't have the proper beam pattern.


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## CaptainQualude (Oct 29, 2008)

*Re: FV-QR (CaptainQualude)*

I did a quick search under HID bulb spacing & confirmed my suspicion. The focal point & a few other things will be off if the bulb isn't spaced correctly. You have to use a spacer between the bulb base & bulb seat of the projector to space the HID to exactly mimic the halogen bulb position.


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## cula (Feb 11, 2010)

What kind of spacer? Where can I find one?


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## CaptainQualude (Oct 29, 2008)

*Re: (cula)*

Are you having beam pattern issues? Most of the issues I've read about are fixed by DIY means. People rig a solution up with what they have on hand. They only pre-made spacers I've ever seen are to convert from one bulb type to another, like a H7 to a DS2.


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## cula (Feb 11, 2010)

I am converting Hella Micro De (H3). Pretty hard so far.


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## CaptainQualude (Oct 29, 2008)

*Re: (cula)*

You'd have to find washers that fit, PVC piping, or whatever else you could figure out.


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