Want to build a spotlight

[Mattmanic]

Hey,

I'm after a powerful light and was originally planning on sticking a 100w bulb in my maglite and calling it a day. But I've now decided, as I have a few 17Ah 12v SLA batteries going spare, that I should make a spotlight.

First of all, is HID really worth it over halogen? Price wise you can get a 35w HID car upgrade kit (ballast, wiring and bulbs) for about £30 or I could get a 250w 24v halogen bulb for £5.

Then ofcourse, I'll need a reflector, and I was planning on just cannibalising one of these: http://cgi.ebay.co.uk/1-MILLION-CAN...ing_LightsLanternsTorches&hash=item5d292df4fa

Would that all work together nicely? And is HID definitely worth the extra money?

Thanks
Matt

EDIT: Upon further ebaying, 55w and 35w HID bulbs and ballast can be had for about the same amount, as the 35W I would've bought included 2 ballasts rather than a single one which I've found in 55w.

 

[kramer5150]

I had one of those lights for about a week. I found it in the recycle bin at work. I eventually tossed it back. really cheap / flimsy construction (even for a spotlight), poor quality switch were the main reasons. But the reflector looked to be of serviceable quality and the front lens is glass. Nothing is glued, so its an easy mod.

I have both 55W halogen and 55W HID, using the same reflector/glass lens in different hosts. I'll take some beamshots for you tonight.

The HID beats it in terns of output... both overall and per watt of power consumption. Both lights are great throwers however. the incan while less Lumens, has a smaller point source (filament), with excelelnt surface brightness so its got some surprising throw. The nice thing about the incan however is its instant-ON capabilities. The HID needs a few seconds to warm up.

 

[Mattmanic]

Yeah, I've got a semi broken one of those spot lights already, the switch is a bit temperamental so I'll probably scrap all the insides and just use that to hold the ballast. Then put a new switch in when I decide where to put the battery.

Beam shots would be great for comparison, thanks

 

[kramer5150]

Heres a quick beamshot... foolish (I know) to white wall hunt these, but at 12:00 this is the best I can do.

I opened all the curtains and set the camera flash to its highest setting in an effort to under-expose the image as much as possible. Still the spot intensity of all 3 lights is excessive. The faint spot on the bottom right is an Xtar D30... FWIW. Its more of an area flood light with no hot spot, so thats why it appears so dim.

From left to right:
55W-HID (5000K) - 55W Incan (H4 Sylvania silver star, automotive lamp) - D30 - Stanley HID (~6500K)

 

[kramer5150]

Yeah, I've got a semi broken one of those spot lights already, the switch is a bit temperamental so I'll probably scrap all the insides and just use that to hold the ballast. Then put a new switch in when I decide where to put the battery.

Beam shots would be great for comparison, thanks

You're better off just replacing the switch all together. Just go to Kragen and get an automotive panel switch. No sense replacing junk with more junk. Oh BTW... many of these lights do not have fuses (!!). This simply is a MUST have with automotive electrical components, $5 for safety and peace of mind is $$$ well spent IMHO.

 

[kramer5150]

Another members' pic from the San Jose CPF meet...

Beams from left to right...
Costco HID, 55W Halogen, DEFT, 55W-HID (5000K), Stanley HID

 

[Mattmanic]

I should have some switches like those around somewhere... How much current will be going though it? Is a mosfet worth the effort/necessary?

EDIT: Loving the red background in that pic

 

[kramer5150]

mosfet??... you mean a 12V relay?
I just wired the switch straight into the 12V+ on the ballast, with a 20A fuse in between the switch and B+.

I don't remember the current capacity spec of my switch, but I do remember picking the one with the highest rating.

 

[Mattmanic]

A mosfet is more or less a solid state relay, but if you haven't used anything like that, I sharn't bother either.

 

[kramer5150]

A mosfet is more or less a solid state relay, but if you haven't used anything like that, I sharn't bother either.

Oh... interesting. I was not aware of that.

Well, I did what I did... doesn't mean its the best. My lights are nothing more than portable automotive electrical systems minus the alternator. So I figure if its good enough for a car, it'll be good enough for me.

Also, my fuse value is probably too high, I think I only need a 15A... but I haven't had a chance to play around with it.

 

[Mattmanic]

I think a 20A fuse would be fine, the battery I'm using will easily blow 200A fuses if it was to short and if it did it would happen suddenly so there probably wouldn't be much difference between using a 20 or 15A fuse. I've got a bag of 20A blade fuses that I use in my airsoft guns, so I'll use those to save me having to buy more specific ones.

 

[kramer5150]

Hey Matt... that yellow host you are looking at is sold at Frys for $17. My local store has a bunch of them... FYI.

 

[lhw1993]

You're better off just replacing the switch all together. Just go to Kragen and get an automotive panel switch. No sense replacing junk with more junk. Oh BTW... many of these lights do not have fuses (!!). This simply is a MUST have with automotive electrical components, $5 for safety and peace of mind is $$$ well spent IMHO.

Why have so many switch in the spotlight that shown in the picture ?

 

[Mattmanic]

I would guess the bottom one is a master switch, middle is low/off/high power for the secondary light, and the top one is to turn the big lamp on.

 

[kramer5150]

Why have so many switch in the spotlight that shown in the picture ?

The bottom switch turns on the small LED light array.

The top switch is the old power switch. This light came OEM with a dual beam Halogen H4 lamp, I for high and II for low. But I disconnected it for the HID+ fuse mod. I could have removed it and covered up the vacant hole, but that switch panel is through hole soldered to a small PCBA on the inside wall of the light. It would have been more trouble than its worth... IMHO. So that I / II switch doesn't do anything.

 

[Mattmanic]

I have now bought my bits:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=160407502805&ssPageName=STRK:MEWNX:IT

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=250648329005&ssPageName=STRK:MEWNX:IT

And the battery I have is: http://uk.rs-online.com/web/1988119.html#header

I had no idea they were so expensive! I've got about 5 of them out of broken electic wheelchairs that were thrown out by a company my brother works for.

Should be ready to put together in about 2 weeks

 

[Mattmanic]

Everything's arrived Putting it together now...

EDIT: And done, it's not pretty but it works and it's bright. Daytime pics to follow...

I'm trying hosting them off Facebook so just tell me if its not working and I'll stick them somewhere else. The ceiling lights were on in these pics and the curtains were open, my camera just underexposed the shots, I'll take some pics outside when it's dark


And a control pic:

And a really bad quality shot to try to show the difference: