Buzzkill

Even the finish can affect the temper colors from what I've seen. I had 2 pieces from the same starting stock where one was a rough finish (around 80 grit) and the other somewhere around 400 grit which I tempered at the same time and they did not have the same colors on the blades afterwards.

440C has gotten kind of a bad reputation, but keep in mind that a knife made from that steel does not mean it has been heat treated properly. A lot of the cheap SS knives have 440C stamped in them, but chances are they are just stamped out and mass produced. From what I've seen from knife makers who handle the steel properly it will perform well, but still not as good as some of the newer SS alloys.

In my limited experience, the thicker your Kastolite the longer it takes to bring your forge up to temperature. However, once it is up to temp, the faster it will bring your stock back up to forging temperatures. It's a trade off but something to think about. If you plan on forging for hours at a time then thicker may be better, but if you like to work for short periods of time you may not want the increased startup time.

I must have missed it the last 5 or 6 times I read the heat treating stickies in addition to the recent review this comment prompted. If it's there I missed it again which could mean I need to slow down and read more carefully, but it might also be an indication that it's worth repeating occasionally for the benefit of others. This is the closest thing I found, which is a different way of saying what I said: "Physics states if there is not enough carbon present, as in mild steel, to form martensite in an appreciable amount of the steel matrix, then no amount of super quench can change that, simpler to use correct steel for the application." While it is clear that mild steel is not a good choice for blades, what is not clear is the cutoff point for steels with regard to carbon content where some hardening benefit may be obtained by using something like superquench. As mentioned here and other places, steels like A36, definitely considered a mild steel, can gain some increased hardness. It's still not a good choice for a blade of course, but the OP put in a lot of time and effort and is trying to make the best out of what he did. I guess my question would be, "What's the down side of trying it?" The work is already done. I'm sure he'll use a more suitable steel the next time around, but can he make his axe shaped object slightly better through the use of superquench?

Recipe: 5 gallons water 5 pounds table salt 28 ounces BLUE Dawn dish detergent 8 ounces of Jet Dry or equivalent. I haven't tried it on anything, so I have no personal experience as to what can be hardened using it. As I understand it, there is a threshold for carbon content below which the steel will not harden regardless of the quench medium, but I'm not sure exactly where that point is. if you read the HT sticky , then you would know

Most coil springs and leaf springs will make decent blades. It's still a good idea to test them first, since there are some out there that do not harden in an oil quench. Lawn mower blades are less predictable. Some will not harden at all and others harden quite well. Again, you'll want to do a test piece before putting in a lot of time and effort on a blade. We generally recommend against used motor oil due to the contaminants that tend to be in it. Unused motor oil is probably not too bad, but is expensive compared to several other alternatives. Canola oil, peanut oil, vegetable oil, or even used fryer oil are safer for you and work ok. The recipe you are referring to is called "Superquench" and is normally used for steels that barely have enough carbon to harden. It provides a very fast quench and would likely cause cracks in a lot of the simple high carbon steels at knife blade thickness.

Any chance you can cut out the bad spots, stuff the cracks with ceramic blanket, and flip it over?

Ceramic supports for kiln shelves might be useful there too.

A few things. If they have the old mud flap hangers which are square steel grab all of those. It's spring steel and I've made knives, punches, chisels, etc. from it. It's small enough that it's not too hard to move. If you're thinking about making hammers, then old S-cams or steer axle king pins might be what you're looking for, but you'll probably need a striker to help move the steel. Coil spring is always good. I don't recommend taking the brake chambers apart to get the springs out. I've done it a few times by putting one in a press and cutting the can off and then releasing the press, but a LOT can go wrong if you're not careful and you could get seriously injured. I usually collect the U bolts that are cut off when leaf springs have to be changed, and I have a few of the leaf springs (3 leaf to 9 leaf stacks), but honestly it's a bear to deal with those with a hand hammer unless you cut them into strips. I haven't used many internal engine components, so I'm not sure what you'd want to grab other than the wrist pins you already got. If I think of anything else I usually grab I'll try to remember to post it, but that's about it for the moment. Oh, I did grab some push rods and head bolts as well, but I haven't done anything with those yet, so I can't comment on how well they can be forged.

I'm not showing it to my wife or I'd have another project to do. Nice work!

obs, it would be well worth your time to look through this post: https://www.iforgeiron.com/topic/52244-japob-just-a-pile-of-bricks/ You do not need special firebricks for your solid fuel forge if you construct it and use it properly. If you are concerned about it, hard fire bricks used for fireplaces and ovens will work fine for the application and are typically available at the big box stores.

In that case the first suggestion of the brass brush trick is probably your best bet, although a durable clear coat could make it last for quite a while.

Just for comparison, here's the Google Translate take: " limp is not as good as the righteous god as a dream come to pass through the guts. "

The rule of thumb is warm the oil. 140 degrees F seems to be about where most people recommend. The reason for warming the oil is its flow rate. As you know warmer oil flows better than cold oil. When we quench that means the vapor pockets around the blade are displaced faster with warm oil than cold oil, which results in a more uniform and fast quench. Oils designed specifically for quenching may or may not need to be warmed. The manufacturer recommendations should be followed for those.

Nah, glycerin is a commonly used substance worldwide. It goes into pharmaceuticals, paint, resins, explosives, cellophane, cosmetics, sausage casings, Pop Tarts, pet foods etc. etc. We haul it on a regular basis at 45,000 lbs per load. I guess that doesn't mean you can easily obtain it in consumer level quantities though.

For forging knives you don't need a long forge. You can only work about 6 inches at a time unless you have a power hammer. However, when it comes time to heat treat knives a longer forge can make life easier. Just for reference, my most recent WIP knife has a blade nearly 12 inches long and currently still has about 7 inches of tang (which will be cut down later). The gas forge I use only has a chamber about 9 inches long (with a pass-through opening), and let's just say that a few more inches of hot steel per heat wouldn't have decreased the time it took to forge.

He's never told us what the piece is, so it makes it hard to suggest a good method for him to get and keep the color he wants.

You could coat it with something like Renaissance Wax, but if it is a piece in which the tempered surface will be handled, rubbed, or otherwise in contact with anything that moves, the tempered color will rub off over time. If the piece is just for looking at, then clear coat or the aforementioned wax will help keep the color without rusting.

Long and skinny means multiple small burners if you want anything approaching even heat inside the forge chamber. Depending on the burner size I normally figure about 4 to 6 inches either side of the burner to be the "hot zone." The temperature seems to me to fall pretty rapidly further than that from the burners I've used. Of course there are a lot of variables that come into play and your mileage may vary.

You're welcome of course, but you may lose your Curmudgeon Card if you aren't careful.

I prefer Stay Brite brand. It's melt/flow temperature is reported to be 430 F. If you have a decent fit and a good bond it's plenty strong enough for guards.

If you work for someone else, you represent them whether you like it or not. If you interact with customers your employer will take into account the impression you will make on them. When hiring someone, if all other things are equal I'm definitely going with the person who has communication skills. If all other things are not equal then it's a judgment call. For me some of your posts on here are hard to follow. I'm not picking on you. I'm just trying to explain that being able to effectively communicate your ideas to others may be significantly more valuable than you seem to think.

I was wearing a T-shirt with that on it at my mom's one day. She asked what the other kind of people was. My response was "You I guess."

Looks pretty darn good for your first try. Just a small suggestion though. If you're not going to put a guard on it then you may want to narrow the tang slightly where it meets the blade. That provides a little more knuckle clearance and makes it less likely that your hand will slip forward on to the cutting edge in use. I'm not suggesting you narrow it much, maybe a quarter inch or so. If you follow the line from the rear of the tang toward the blade it should give you a good result. Keep the rounded shape you have though. You don't want sharp inside corners as they are stress points for breaking. I'm looking forward to seeing it finished.

I still don't know for sure what it is from, but that's not like any axle shape I've seen. Due to the shoulder and flat spots it looks more like a bit for a large machine to me. If it was used to crush rock or some similar function it should wear very well as an anvil, though it may be difficult to grind. Anyway, looking good on the anvil stand. I am looking forward to seeing what you can do with it.