Should you pour boiling water on a knife?

I do not do it, but most tempering is done at 300deg+ so a quick dunk in 212deg water would probably not hurt it but that is just a guess on my part. I was taught in the scouts not to do it for the very reason of ruining the temper. We always always just cleaned and dried our utensils after use and none of us ever got sick.

Warm soap and water and drying it completely will be sterile enough in my opinion.
 
Tempering is generally accomplished by heating from 350-660 deg Fahrenheit for two hours. A quick rinse of several seconds at 212 deg will do nothing to the temper, IMO, as will not raise the temperature of the blade more than a few degrees.
You are MUCH more likely to harm the rather thin edge by careless grinding, which can dramatically raise the temperature very quickly.
 
Last edited:
The blade temper should not be affected, but the adhesives used on many knives/handles are likely to fail or to be weakened by boiling. Some superglues and many epoxies are not designed for temperatures above 180 degrees. Better safe than sorry.
 
Nope it won't ruin temper at all, water boils roughly at 210.

I've boiled my Buck 124 for 10 minutes to remove the handles and the epoxy.

DSC01237.jpg


afterwards

DSC01273.jpg

DSC01280.jpg

DSC01277.jpg
 
The water can only get to 212F but the pot you boil it in can get hotter. Be careful if you're dropping the knife in a pot with boiling water. Sitting on the bottom the knife can get hotter than 212.
 
Won't hurt it at all.

As already pointed out, there is also the 'time' factor to be considered. It's not just 'temp' but 'temp over time'.


While pouring boiling water over a knife would be better than cold water for sterilization, just how much sterilization is actually being done is questionable.

Way back when we used glass baby bottles, the rule-of-thumb was that they had to be boiled for at least 5 minutes to be considered 'sterilized'.
 
To sterilize it, how about just soap and lather for a bit, then rinse under running water? If you want more, then wipe it down with 70% isopropyl alcohol. 90% IPA is less of anti-bacteria solution counter-intuitively.

I use my knife a lot for food and I just use soap and water. If it fell into a pile of feces, I'm just going to get another knife.

If your knife has anything plastic like KVT bearings, won't the plastic possibly deform?
 
i vote the isopropyl alcohol. we use it to clean fiber optics and etc. i use either that or soap and water.
 
Regular hand soap works fine for me, or in a pinch some hand sanitizer or alcohol pads. I don't really eat with mine too much though.
13349407
 
Just a thought, but I bet the inside of some knife sheaths have some nasty bacteria!
 
I work in pharma, and we use 99% isopropyl alcohol on everything. I use it on my knives all the time to clean up tape residue from opening boxes and what not.
 
WK ONE said:
I work in pharma, and we use 99% isopropyl alcohol on everything. I use it on my knives all the time to clean up tape residue from opening boxes and what not.
Click to expand...

99% is good as a solvent (cleaning tape gunk off) but 70% is actually better at killing bacteria. More water in it means it will pass better through the cell wall, but the alcohol content is still plenty high enough to kill it.
 
JonathanCharles said:
Hey BF friends!

As far as sterilization goes, does pouring boiling water on a knife ruin the temper?

Thanks!
Click to expand...
It won't ruin the temper, you would need to be at several hundred degrees for a while before that happens. As for sterilization, there are many better ways to clean a knife.
 
No way boiling water will affect the temper of steel. You could boil it all night.

Handles, bearing cages, liners, anything other than steel,I would not boil.

If your purpose is sterilization there are easier ways to do it, as noted above. If you're talking a small knife or folder a quick Bic flame or a coal will do the job much faster...or flame a touch of Purel along the edge for those necessary minor surgeries.
 
To really sterilize a knife you would need sterile water and an autoclave that would steam it at 270° for 30+ minutes. That's pretty much the only way to get a truly sterile tool. Luckily, unless you're going to perform surgery with the knife, washing it with soap and hot water is typically more than enough. If it got blood on it and you're worried about bloodborn illnesses, clean it with a solution of 1 part bleach to 10 parts water or just clean it well with soap and water and put it away for at least 30 days. Same drill with other bodily fluids.
 
Pretty much been covered, but I'll second what others have said...

Rappy said:
Nope it won't ruin temper at all, water boils roughly at 210. I've boiled my Buck 124 for 10 minutes to remove the handles and the epoxy.
Click to expand...

That's correct; the only real danger from heat below about 350F is to the handle materials and epoxy. That's one reason I don't recommend ever putting a knife in a dishwasher. (the others being that stuff tends to rattle around in there, and many detergents are fairly abrasive, both of which are bad for sharp edges and fine finishes.)

To sterilize the steel, you're better off with isopropyl alcohol or bleach anyway. (be aware, bleach will pit and even rust plain carbon steels if left on for a while, and may not be good for some handle materials and other incidentals... just stick with iso. )
 
You must log in or register to reply here.
Back
Top