My first blade that lived, and a question or two.

A

Any Cal.

BANNED
Joined
Jan 1, 2006
Messages
1,404
Hi all. I finally have a blade that lived through the quench/heat treat process. This is the first one out of my $28 forge. Stock removal 1080, heat to nonmagnetic in forge, edge quench in motor oil. Triple temper at just over 400 in the oven. I am wondering if anyone can has the charts for 1080, or a link to them. Also, if anyone w/ experience w/ 1080 can look at the pic and tell me if I have too much heat in the tempering process. I sharpened the knife after 1 hr at 400F, and on a brass rod test I got some minute chipping. After the
1st hr, the knife was a very light straw. After the second hour, it was a darker straw. The pic shows it know. I edited the brightness of the pic so it would look about like I see it in real life. Please let me know if the color says I got it too soft and need to HT all over again. I am trying for a knife w/ toughness more than edge holding, but don't want it too soft. Thanks for looking.



edited to add: Sorry, looking at the pic, it still does not look right. I would have to call the knife a med. rose color. It is the same color as the picture, but not dark like the pic shows.
 
I tried running the edge over the rod again, and now it seems fine. No chipping or rolling over the edge. I think I am going to go ahead and put a handle on it.
 
Sounds good. It doesn't hurt to cut some stuff with it too, unless you're concerned about scratching the finish.

The last file-knife I tempered came out purple after the third cycle at 375. I about filled my pants! Turns out it was just oil from my fingers that turned purple, it wiped right off. That's my best guess anyway. The steel was a nice bronze color underneath and the edge came out perfect as far as my brass rod test can tell.
 
ive been using 1080 and i find that tempering it at 375 for one hour and doing it three times works really good. 400 is just a little to hot. you can still try it out and if it doesnt seem hard enough or something just re heat treat it. im not en expert on 1080 but i have a good understanding of it. if you have other questions, i can answer them to the best of my knowledge.
 
I'd like to add a couple more comments from a fellow newbie...

I've found that 350 is a good starting point for tempering. Most likely too low, but not likely to soften your edge too much. I reckon it's better to start tempering too low, and raise the heat next cycle if the steel is still too hard.

Color is a notoriously unreliable indicator. I've made my living as a pressman for the last decade or so; judging color is a huge part of my job. Believe me, judging color by eye is very subjective, even among trained professionals. Three experienced men with good eyes can look at a printed sample and have 3 different opinions on its tint, hue, brightness, etc. When you start trying to compare a piece of steel to a chart in a book or online, or in a digital photo, forget it. Charts, color swatches or PMS books are only a beginning guideline.

All this is insanely hard to quantify when using the kitchen oven (like I am). I started at 350 (pre-heated, I think it makes sense to let the oven come up to heat before putting the blank in, for the sake of consistency) on my first couple file-knives, and bumped it up to 375 with no apparent loss in strength or toughness. To be somewhat reliable and accurate, one would have to at least get an oven thermometer and check whether "375" on the dial really means 375 in the oven. I confess, I haven't checked this yet in my own shop/kitchen.

A one-hour "soak" at tempering temp seems to be minimum; I think more time allows the steel to come up to temp all throughout, and go through those mysterious transformations. Everything I've read says to temper three times for at least an hour each time, to ensure a full and even treatment. Your experience with the edge chipping after the first cycle, but holding up nicely after three cycles, seems to corroborate this.

I haven't read anything that says "soaking" too long at these relatively low temps will harm the HT/hardness. I have read a lot of articles saying that the first temper cycle doesn't always complete the process.

For guys like me, starting out with a bare minimum of equipment, the best way is to test, test, test. Use the brass rod. Whittle hardwood or cut rope until the knife gets dull, and see how difficult it is to re-sharpen with your usual sharpener. All this can be a pain in the neck, but how else will you know if it's good enough?
 
Looks Good Man. I'm Working on two Knives right now. and one of them is gonna be like mine so i hope to do my first handle job on it when im done. If..... all goes well. the other ones for my brothers girlfriend, drill a hole or 2 give it a cord handle. ill make sure to post both before temper.
 
I don't know about the colors. The knife's edge seems to sharpen well w/ out chipping or rolling. Overall, I am happy with it. Here it is w/ the handles on it. Now I'm off to make it a sheath.




The dark end of the blade you see is a reflection from beside me.
 
You must log in or register to reply here.
Back
Top