MI-Lasers 543 bare tube!!![pics]

[ultimatekaiser]

Kaiser, this is where we agree to disagree:

The rule I've used for the past 20 years is Acetone is for Grease, Methanol for everything else. And Methanol for intra-cavity use. While Methanol is more agressive, it usually leaves less residue, vaporizes better, and has less interaction with residual UV from the plasma then Acetone. SP, Coherent, and the top three makers of industrial YAGS agree with me in their manuals.

My Employer (5th largest scientific laser producer) bans Acetone from use unless a fingerprint is the culprit. Acetone attacks the edges of certain kinds of coatings over time, especially ultrafast coatings.

Europe pushes Methanol as toxic, where in the States its more accepted.

So we used Ethanol when on training missions in Europe.

For home use (IN USA) on a HENE I'd use 90 per cent Isopropyl from a drug store. While there get some Puritan brand throat swabs with wood sticks. Usually the pharmacist has them in better drug stores, and no prescription is required, but you will have to explain why you ask for them. The sterile wood ones use no glue to hold the cotton on, unlike ordinary household Q-Tips. The solvent dissolves the glue, and you end with more residual Crud on your optics. The wood has been gas sterilized, and this removest the easily dissolved organics. If your quick, and if you flush the swab once, there is no residue from the wood. A single package of Lens Tissue from Thorlabs is cheap if sent postal. The better the swab or lens tissue, the less the likelyhood of scratches.

Steve

This is pretty much my rule of thumb too, but I have lately found my methanol leaving more of a film recently, so perhaps its just getting too much water in it? As a result perhaps my opinion is a bit biased.

Most of the time I do what you described above with 90% isopropyl with no additives and cotton lens tissue pads from Thorlabs. I have yet to see a scratch or damage from it. I find acetone is indeed amazing for fingerprints, which are usually the culprit on a lot of my stuff, or dust (which I use air for). I find the saturation is what makes alot of difference when cleaning with it. too much leaves a film, and too little has less effect. I find that about 2-3 moderate sized drops on one of those swabs works best in either case.

 

[LSRFAQ]

Films come from mainly three/four things:

1. Interaction with bottle materials. (Yes, Even Glass over time, Na ions)
2. Water adsorption.
3. Added Tracers / Denature Additives in the cheap stuff.
4. inadvertent additives picked up in packaging, ie shipped in reused 55 gallon drums before packing.

I used to have my materials shipped under Argon.

Steve