Ok so I did further testing...…and I have a new fix to report.
I had indicated the insulation helps...…This is not necessarily true. It will be hit or miss.
Point of clarification: I have two telescopes, with two GLP's
Both are cheapo GLP's from ebay.
I put insulation on both.
One of them works pretty well in the cold with insulation.
The same insulation on the second one does nothing, and it is horrible in the cold (flickers)
Here are other things I tried
1) Tried a chemical hand warmer - created a plastic "sheath" to hold it in place from a water bottle.
result = did not work. The plastic cover did not allow the hand warmer to get the air needed for the chemical reaction
the hand warmer did not heat and the idea was a fail.
2) Tried a chemical hand warmer - with a "chicken wire" cover to hold it in place. The idea being that the chicken wire would allow
airflow to the hand warmer to maintain the chemical reaction.
result = did not work. There was still too much contact between the laser and the chemical hand warmer to restrict air.
The chemical hand warmer again did not heat properly and the idea failed, laser still just barely flickering.
3) Tried to rubber band a chemical hand warmer to the laser.
result - did not work. I think my laser pointer holder interfered too much with the hand warmer and I could not get the hand warrmer in a decent position with just rubber bands. I could not get the hand warmer heat to transfer the heat to the laser this way.
I found a new inexpensive fix / solution that I believe will work. I probably won't know with certainty until next winter, as our 30 degree (and lower) temperatures are gone and we are moving into overnight lows in the 40's.
I found a battery powered "foot warmer" for under $20 on amazon.
It is on a cardboard like material. I rolled the cardboard around the laser, heat side in, and then taped it with electrical tape.
I upgraded the battery pack from two aa batteries (in series wiring for 3 v) to two 3.7v 18650 batteries (wired in parallel) for slightly higher power, plus I have extra 18650 batteries and a charger for them.
The heat gun registered the laser at 111 degrees. In my house at about 70, this is a 41 degree increase.
Looks like this method will be effective to keep those cheapie GLP's working in the cold.
I mounted the battery holder to the scope with silcon glue (goop) Now if I will be observing in cold temps, I can just pop in
batteries for the laser warmer.
Photos : 1) How the foot warmer comes out of package 2) Temp gun test 3) On the Scope
Edited by Sky_LO, 28 January 2020 - 05:15 PM.