danielpokey
New Member
- Joined
- Apr 6, 2019
- Messages
- 16
For Thermacell DIY refills, lots of tips out there for the butane bottle refill, removing the check valve, etc. Those all work great. But for the pads, what are some better-performing methods? The chemical in the pads is allethrin, which is not easy to find in bulk compared to permethrin. None of these class of chemical compounds are very soluble in water, so simple dilution of the ag use 10% permethrin with water will not create an evenly-sprayable mixture. So here's my solution so far (disclosure, I'm a professional R&D chemist, but not a formulator, so I used basic solubility info to estimate this).
Dilute 10% pemethrin with acetone (drug store nail polish remover or home store paint section) 1:9 to achieve 1%. Soak the old pads for about an hour in this solution, then lay them out on a wire mesh grid or screen for about 3-4 hours to dry. Then give them a very light water spray with fine mist from a spray bottle, and then immediately bag them individually in the smallest zip lock bags that will hold them. I haven't tested for bug repellent effectiveness yet, still have a few store-bought Thermacell pads left, but this solves the problem of solubility for dilution and also adds some water at the end to aid in the heated evaporation when put to use.
For clothing treatment, I found this approach is actually really effective, and leaves basically no smell. Take 10% permethrin, dilute 1:19 with the highest concentration drug store isopropanol you can find (I think mine was 92%) to achieve 0.5%. I used isopropanol for the clothing instead of acetone to decrease chance of camo or fiber damage. I also like the small pump pressure spray bottles instead of trigger spray bottles to get an even spray. Lay the clothing flat and spray evenly. You may see a slightly oily looking appearance at first, but it will dry to be invisible on your camo. Once dry, flip over, spray the other side. Once second side is dry, hang on the line outside for about a day to allow all isopropanol to evaporate and any possible residual smell to dissipate. Done! No ticks, no mosquitoes! Performs as well as Sawyers or other commercial permethrin sprays.
Dilute 10% pemethrin with acetone (drug store nail polish remover or home store paint section) 1:9 to achieve 1%. Soak the old pads for about an hour in this solution, then lay them out on a wire mesh grid or screen for about 3-4 hours to dry. Then give them a very light water spray with fine mist from a spray bottle, and then immediately bag them individually in the smallest zip lock bags that will hold them. I haven't tested for bug repellent effectiveness yet, still have a few store-bought Thermacell pads left, but this solves the problem of solubility for dilution and also adds some water at the end to aid in the heated evaporation when put to use.
For clothing treatment, I found this approach is actually really effective, and leaves basically no smell. Take 10% permethrin, dilute 1:19 with the highest concentration drug store isopropanol you can find (I think mine was 92%) to achieve 0.5%. I used isopropanol for the clothing instead of acetone to decrease chance of camo or fiber damage. I also like the small pump pressure spray bottles instead of trigger spray bottles to get an even spray. Lay the clothing flat and spray evenly. You may see a slightly oily looking appearance at first, but it will dry to be invisible on your camo. Once dry, flip over, spray the other side. Once second side is dry, hang on the line outside for about a day to allow all isopropanol to evaporate and any possible residual smell to dissipate. Done! No ticks, no mosquitoes! Performs as well as Sawyers or other commercial permethrin sprays.
