cityevader
Enlightened
Hello, my name is Cityevader, and I'm a flashaholic.
First post here, and I'm having issues in deciding what to do with my 12 year old Performance Viewpoint/Marwi dual headlamps with 5ah 6v SLA with mr11 bulbs. I used to be happy with the 6w flood and 12w spot, although runtime was short. I'm finally down to my last bulb (the 6w 30° beam) and every replacement I've tried is terribly dim and orange as if they're 12v running on 6. The new 10W bulbs are easily half as bright as the 6!!! All I can think of is that the originals were overvolted 5v??? I was really close to getting a ginormous 12v SLA and some 12v car foglights (with more easily modified mr16 bulbs), but I'm cheap cheap cheap. I'll spend hours and days whittling on something to do it homemade and cheaper...so I'm keeping the 6v SLA and charger.
Now the allure of LEDs is calling, but all I read is that mr11's are too difficult for LED's due to heat transfer lacking. And there are slim to no kits except Cutter's $75 one...gulp! So I made some cups from copper end caps. Scribed a perfectly straight line at required depth from bottom, and soldered on a loop of 12ga copper wire to act as a lip for mounting (like the mr11) and then soldered on a layer of stranded wire (to take up the gap between cup and housing) and chucked it up in a drill and slowly filed it down until it tighly squeezed into the lamp housing, giving a good 3/8" contact patch that will be slathered in thermal grease.
Now is where you guys and gals come in...deciding/designing of the LED system. A P7 would be nice, but I don't need ultra super bright. Since there are two lamps, I'm thinking a pair Cree XRE Q5 at about 750mA might be what I'm after, although I've never experienced these before. Each lamp will be on it's own switch. One wide beam, one spot.
The cups are limited in depth to 15mm for star emitter and lens. An L2 lens holder from ledsupply is about 13mm and has multiple lens patterns that I would love to try.
Q's:
How tall is the star portion that the lens sits on?
Would the XRE's have adequate output at 750mA (to keep heat down)? Or 1000ma for a mild increase in output? and would these be similar to combined 6W plus 12W halogens together? similar=fine, more=great, but notably less=bad
Information overload doing research...so I really need help with driver selection for use with 6v SLA battery. Likely a driver for each bulb since I want them on/off separately and using stock switches. Ideas?
Edited with pics. It's vastly easier to cut the cup to length first. Scribe a line as shown in mock up pic, keeping blade still and spinning the cup, then cut it carfully with saw/grinder/file/appropriate tool. Then use a smaller diameter pipe (3/4") to wrap some solid wire around to form the rings. Solder the rings on first, then wrap with wire (mock up pic) and solder that second.
First post here, and I'm having issues in deciding what to do with my 12 year old Performance Viewpoint/Marwi dual headlamps with 5ah 6v SLA with mr11 bulbs. I used to be happy with the 6w flood and 12w spot, although runtime was short. I'm finally down to my last bulb (the 6w 30° beam) and every replacement I've tried is terribly dim and orange as if they're 12v running on 6. The new 10W bulbs are easily half as bright as the 6!!! All I can think of is that the originals were overvolted 5v??? I was really close to getting a ginormous 12v SLA and some 12v car foglights (with more easily modified mr16 bulbs), but I'm cheap cheap cheap. I'll spend hours and days whittling on something to do it homemade and cheaper...so I'm keeping the 6v SLA and charger.
Now the allure of LEDs is calling, but all I read is that mr11's are too difficult for LED's due to heat transfer lacking. And there are slim to no kits except Cutter's $75 one...gulp! So I made some cups from copper end caps. Scribed a perfectly straight line at required depth from bottom, and soldered on a loop of 12ga copper wire to act as a lip for mounting (like the mr11) and then soldered on a layer of stranded wire (to take up the gap between cup and housing) and chucked it up in a drill and slowly filed it down until it tighly squeezed into the lamp housing, giving a good 3/8" contact patch that will be slathered in thermal grease.
Now is where you guys and gals come in...deciding/designing of the LED system. A P7 would be nice, but I don't need ultra super bright. Since there are two lamps, I'm thinking a pair Cree XRE Q5 at about 750mA might be what I'm after, although I've never experienced these before. Each lamp will be on it's own switch. One wide beam, one spot.
The cups are limited in depth to 15mm for star emitter and lens. An L2 lens holder from ledsupply is about 13mm and has multiple lens patterns that I would love to try.
Q's:
How tall is the star portion that the lens sits on?
Would the XRE's have adequate output at 750mA (to keep heat down)? Or 1000ma for a mild increase in output? and would these be similar to combined 6W plus 12W halogens together? similar=fine, more=great, but notably less=bad
Information overload doing research...so I really need help with driver selection for use with 6v SLA battery. Likely a driver for each bulb since I want them on/off separately and using stock switches. Ideas?
Edited with pics. It's vastly easier to cut the cup to length first. Scribe a line as shown in mock up pic, keeping blade still and spinning the cup, then cut it carfully with saw/grinder/file/appropriate tool. Then use a smaller diameter pipe (3/4") to wrap some solid wire around to form the rings. Solder the rings on first, then wrap with wire (mock up pic) and solder that second.
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