70% should do fine. Use a q-tip to wipe it on. Just don't let it evaporate on its own to dry, you need to use another q-tip or two to "mop" it up dry. Any particles or oils picked up by the isopropanol will want to adhere to the liquid. If you let it evaporate away, you're just re-depositing the crap back onto the lens. You need to physically remove the liquid, while it's still a liquid. Benefit of 70%, is it won't evaporate as quickly as 91% or 99%, so you have a little extra time to wipe it away. Downside is that it won't "grab onto" particles or oils as strongly (the crud will have lower solubility in 70%)Thanks for the info man I only have 70 percent iso rn so I hope that’ll work fine. Sorry if this sounds stupid haha but where is the diode window located on a laser pointer? If I unscrew the entire top cap with the lenses the diode is right underneath but there’s no little piece of glass over it.
Does anybody know of a good alternative to q-tips, that won't shed any of it's... "hairs"?