Snoopy
Newly Enlightened
- Joined
- Oct 5, 2004
- Messages
- 41
Over the past few years the well-known MR16 reflector halogen lamps have been used for a variety of flashlight modifications. They are easily available from stores everywhere (i.e. no group buys, machining, ...) at a low price, provide a homogeneous beam pattern, and their Palladium coating has a high reflectance and does not oxidize. Last but not least, integration into a Maglite-D lamp head is straightforward. Unfortunately, the range of bulbs is limited to 12V long-life types with relatively low efficiency. Moreover, beam divergence is comparatively large for flashlight applications and the focus is fixed. A minor modification removes these disadvantages and allows to use a broad variety of single-ended halogen bulbs with variable focusing capability. This is achieved by removing the rear part of the lamp socket and the bulb.
The patient is an 'Osram Decostar IRC' reflector lamp with 10 degrees beam divergence. To cut off the socket I use a Dremel/Proxxon drilling machine with Carborundum or Silicon Carbide grinding bit of 20 to 30mm diameter and a drill stand. The lamp is placed on the front glass and the bit's lower edge is aligned with the transition between reflector and socket (Figure 1).
Figure 1: Set-Up
Move the lamp along the rotating bit to produce a groove of constant depth. Don't apply too much pressure, especially when you're almost through the glass. This requires some patience and it is advisable to practice with a cheaper model. As soon as the socket is cut off, the cement that holds the bulb can be removed and the bulb will fall down on the front glass. Insert a small screwdriver into the cavity and break the front glass. Carefully peel off the fragments and smoothen all sharp edges. DONE! The result should look like this:
Figure 2: The Modified Reflector
Those who plan to use lamps of 10+ watts should also replace the standard polycarbonate front lens and rubber o-rings. The finished lamp head is shown in Figure 3. The bulb is an Osram 64625 HLX
Figure 3: Finished Lamp Head
Final remarks: 1.) The procedure described above has worked for me. I can not give any warranty on it's success for others. 2.) I am not responsible for any damage or injury arising from application of this procedure.
Please let me know what you think.
Snoopy
The patient is an 'Osram Decostar IRC' reflector lamp with 10 degrees beam divergence. To cut off the socket I use a Dremel/Proxxon drilling machine with Carborundum or Silicon Carbide grinding bit of 20 to 30mm diameter and a drill stand. The lamp is placed on the front glass and the bit's lower edge is aligned with the transition between reflector and socket (Figure 1).
Figure 1: Set-Up
Move the lamp along the rotating bit to produce a groove of constant depth. Don't apply too much pressure, especially when you're almost through the glass. This requires some patience and it is advisable to practice with a cheaper model. As soon as the socket is cut off, the cement that holds the bulb can be removed and the bulb will fall down on the front glass. Insert a small screwdriver into the cavity and break the front glass. Carefully peel off the fragments and smoothen all sharp edges. DONE! The result should look like this:
Figure 2: The Modified Reflector
Those who plan to use lamps of 10+ watts should also replace the standard polycarbonate front lens and rubber o-rings. The finished lamp head is shown in Figure 3. The bulb is an Osram 64625 HLX
Figure 3: Finished Lamp Head
Final remarks: 1.) The procedure described above has worked for me. I can not give any warranty on it's success for others. 2.) I am not responsible for any damage or injury arising from application of this procedure.
Please let me know what you think.
Snoopy
