I made extension tubes for the ITP A3 EOS to work with 2 X AAA or 3 X AAA batteries.
1. step Cutting 9mm from the lamp head
2. step Cutting the end of the main tube, preparing both ends
to get the right size before fitting them together.
3. step Press parts together and fix them with glue
As a first result I got a lamp with 2 X AAA batteries and approx. double
light output. Weight 15g (39g with 2 X eneloop)
My cutted lamphead is good enough to make some further investigations
I still tried to open it by just turning both parts--No chance!!! Than I baked the part out in my kitchen ofen at 100°C to
make the glue weak. No chance again to
loose the parts by turning the hot parts.
As a last step I tried it with the solvent acetone. ( attention! very aggressive against most materials ) Some small drops of acetone were applied with a syringe only to the thread. No chance to get the glue weak!!
So I finaly ended with my DREMEL to
seperate the parts.
By the way--it is very good that the head is not easy to disassaeple because that means that there is enough glue within the threads to make sure that the
heat transfer to the aluminium body works perfect.
Now I had some more ideas:
1. Another try with more acetone ( before that I remove the electronics)
2. Measure the head temperature with 2 x eneloops and 2 x L92 batteries.
3. Apply a Cree XP-G emitter
The experience with the solvents was terrible. I tried Acetone and paint thinner for more than 2 days. As result the lamp head was destroyed completely. The lens peeled away from the Cree and also the aluminium
from the reflector was peeled away. There was no chance to open the
lamp head!!
Conclusion: If they applied enough glue during production there is no
chance to open the lamp head without destroying it.
(I bought 8 lamps and only 1 had not enough glue. There the head was easy to open and I used this for the Cree XP-G modification)
As next I measured the head temperature, 12mm from the front lens, at 20° ambient temperature.
1. Measure the head temperature with 2 x eneloops and 2 x L92 batteries.
Max. temperature is reached after 20 min. With 2 X L92 (3V) I measured
57°C outside and with 2 X eneloop (2.4V) 50°C . My feeling is that we have to add 15°C to get the LED temperature, resulting in 72°C and 65°C.
With a Li-ion battery (3.7V) we may end at 80°C.
I can accept 72°C but dont want to go to 80°C. Not only because of the stress to the Cree led. We have to take in account that the led is fixed
with thermal paste to the heatsink and this paste is a kind of paraffine which can evaporate at higher temperatures. The effect may be condensation at the front lens which can never be cleaned because it is not possible to open the lamphead. For this reason I also removed the grease from the front thread completely and applied just a little bit of a special bicycle oil.
As I told you above it was possible to open 1 lamphead very easy with
a tweezers. This was used to build in a Cee XP-G emitter.
Arctic Silver 5 was used as glue to fix the emitter at the heatsink and also
to assemble the lamphead again.
The resulting ITP A3 with Cree XP-G is not visibly brighter compared to the
old Cree XP-E. One reason is that there is more spill because of the bigger
led area. I personally like the throw of the old version, especialy with the brightness of 2 XAAA or 3 X AAA. So my decision was to use the XP-G version at my key chain because there it is usefull to have more spill.
Now finally some words to the 3 X AAA version. From the destroyed (solvets) lamp I made a second extension tube. Now it is possible to
use the ITP A3 with 1 , 2 or 3 AAA batteries.
Here is a picture from the 3 X AAA version
The weight is 20g (56g with 3 X eneloop). This lamp should have around 240 lumens but I don´t have an IS till now to verify this. Nevertheless the
3.6 V make the lamp remarkable bright and I used it very often for cross
country skiing during night as a head lamp. There the outside temperature
was below 0°C so the lamphead did not come above 50°C in HIGH.
Wachtel
1. step Cutting 9mm from the lamp head
2. step Cutting the end of the main tube, preparing both ends
to get the right size before fitting them together.
3. step Press parts together and fix them with glue
As a first result I got a lamp with 2 X AAA batteries and approx. double
light output. Weight 15g (39g with 2 X eneloop)
My cutted lamphead is good enough to make some further investigations
I still tried to open it by just turning both parts--No chance!!! Than I baked the part out in my kitchen ofen at 100°C to
make the glue weak. No chance again to
loose the parts by turning the hot parts.
As a last step I tried it with the solvent acetone. ( attention! very aggressive against most materials ) Some small drops of acetone were applied with a syringe only to the thread. No chance to get the glue weak!!
So I finaly ended with my DREMEL to
seperate the parts.
By the way--it is very good that the head is not easy to disassaeple because that means that there is enough glue within the threads to make sure that the
heat transfer to the aluminium body works perfect.
Now I had some more ideas:
1. Another try with more acetone ( before that I remove the electronics)
2. Measure the head temperature with 2 x eneloops and 2 x L92 batteries.
3. Apply a Cree XP-G emitter
The experience with the solvents was terrible. I tried Acetone and paint thinner for more than 2 days. As result the lamp head was destroyed completely. The lens peeled away from the Cree and also the aluminium
from the reflector was peeled away. There was no chance to open the
lamp head!!
Conclusion: If they applied enough glue during production there is no
chance to open the lamp head without destroying it.
(I bought 8 lamps and only 1 had not enough glue. There the head was easy to open and I used this for the Cree XP-G modification)
As next I measured the head temperature, 12mm from the front lens, at 20° ambient temperature.
1. Measure the head temperature with 2 x eneloops and 2 x L92 batteries.
Max. temperature is reached after 20 min. With 2 X L92 (3V) I measured
57°C outside and with 2 X eneloop (2.4V) 50°C . My feeling is that we have to add 15°C to get the LED temperature, resulting in 72°C and 65°C.
With a Li-ion battery (3.7V) we may end at 80°C.
I can accept 72°C but dont want to go to 80°C. Not only because of the stress to the Cree led. We have to take in account that the led is fixed
with thermal paste to the heatsink and this paste is a kind of paraffine which can evaporate at higher temperatures. The effect may be condensation at the front lens which can never be cleaned because it is not possible to open the lamphead. For this reason I also removed the grease from the front thread completely and applied just a little bit of a special bicycle oil.
As I told you above it was possible to open 1 lamphead very easy with
a tweezers. This was used to build in a Cee XP-G emitter.
Arctic Silver 5 was used as glue to fix the emitter at the heatsink and also
to assemble the lamphead again.
The resulting ITP A3 with Cree XP-G is not visibly brighter compared to the
old Cree XP-E. One reason is that there is more spill because of the bigger
led area. I personally like the throw of the old version, especialy with the brightness of 2 XAAA or 3 X AAA. So my decision was to use the XP-G version at my key chain because there it is usefull to have more spill.
Now finally some words to the 3 X AAA version. From the destroyed (solvets) lamp I made a second extension tube. Now it is possible to
use the ITP A3 with 1 , 2 or 3 AAA batteries.
Here is a picture from the 3 X AAA version
The weight is 20g (56g with 3 X eneloop). This lamp should have around 240 lumens but I don´t have an IS till now to verify this. Nevertheless the
3.6 V make the lamp remarkable bright and I used it very often for cross
country skiing during night as a head lamp. There the outside temperature
was below 0°C so the lamphead did not come above 50°C in HIGH.
Wachtel
.
