hot cut hardy

[pkrankow]

This is based on information in this thread
http://www.iforgeiro...-hot-cut-hardy/
NakedAnvil took an axle, squared and upset a shank on, then formed a wedge for a hot cut in (according to him) about 30 minutes. I know he has induction heating, which is VERY fast and that he knows a whole lot more than me.

I started off with a piece of 1 1/2 4140 in my propane forge, I formed the square shank then cooled the top in water (so I don't upset it in too far) and upset the shoulder on the bottom using a bolster plate wired to my anvil (it lines up with the hardy rather well)

I actually upset 2 so I could make a turning fork out of one, and a hot cut out of the other. Took me a little over an hour, and I made a hot chisel as well from some coil spring. (I heat treated that today)

I MELTED a part of a punch I was making as well, so I know I get enough heat out of the forge The scale was molted every time I removed the part, so I think I was hot enough.

Today I tried to draw out the top of the hardy into a wedge shape. I am using a 3# diagonal peen hammer. I found that half face blows were the only way I could move metal on this thick stuff. My arm feels like jelly, largely because I do not do this enough.

I formed a wonderful fish mouth or bird beak, depending on who you read last. I could not get the metal to move differently, so I hot cut (chiseled) one side of the fish mouth away. I do not know if this is right or wrong, but I did it. I know a fish mouth is formed by not hitting hard enough to move the metal in the center of the bar.

I gave it up for the day when while drawing down the other half of the fish mouth a crack formed, probably from a cold shut formed while chiseling. I heated the part to normalize, and put it aside to cool and picked up since I was also nearly out of time.

Here are some pictures of the process, and where I stopped. I welcome suggestions on what to do. I thought about grinding out the shut using my angle grinder and a cup disk (I hope I called that right)

The most fun so far was when I upset the shoulders with round house strikes and an 8# sledge.

Phil

[bigfootnampa]

This is based on information in this thread
http://www.iforgeiro...-hot-cut-hardy/
NakedAnvil took an axle, squared and upset a shank on, then formed a wedge for a hot cut in (according to him) about 30 minutes. I know he has induction heating, which is VERY fast and that he knows a whole lot more than me.

I started off with a piece of 1 1/2 4140 in my propane forge, I formed the square shank then cooled the top in water (so I don't upset it in too far) and upset the shoulder on the bottom using a bolster plate wired to my anvil (it lines up with the hardy rather well)

I actually upset 2 so I could make a turning fork out of one, and a hot cut out of the other. Took me a little over an hour, and I made a hot chisel as well from some coil spring. (I heat treated that today)

I MELTED a part of a punch I was making as well, so I know I get enough heat out of the forge The scale was molted every time I removed the part, so I think I was hot enough.

Today I tried to draw out the top of the hardy into a wedge shape. I am using a 3# diagonal peen hammer. I found that half face blows were the only way I could move metal on this thick stuff. My arm feels like jelly, largely because I do not do this enough.

I formed a wonderful fish mouth or bird beak, depending on who you read last. I could not get the metal to move differently, so I hot cut (chiseled) one side of the fish mouth away. I do not know if this is right or wrong, but I did it. I know a fish mouth is formed by not hitting hard enough to move the metal in the center of the bar.

I gave it up for the day when while drawing down the other half of the fish mouth a crack formed, probably from a cold shut formed while chiseling. I heated the part to normalize, and put it aside to cool and picked up since I was also nearly out of time.

Here are some pictures of the process, and where I stopped. I welcome suggestions on what to do. I thought about grinding out the shut using my angle grinder and a cup disk (I hope I called that right)

The most fun so far was when I upset the shoulders with round house strikes and an 8# sledge.

Phil

Phil I doubt this is news to you but I don't think your hardy looks near as nice as the one that 82 year old guy (Grant) made in half the time! (;-) No criticism intended... just sayin.

[pkrankow]

Phil I doubt this is news to you but I don't think your hardy looks near as nice as the one that 82 year old guy (Grant) made in half the time! (;-) No criticism intended... just sayin.

I know he is an old fart, but I didn't think he was that old! Yea, Grant's looks a lot better, and he may have been doing this longer than I have been alive. His profile says 62.

I needed that laugh too!

Phil

[Nakedanvil - Grant Sarver]

Well, 1-1/2 inch is pretty big to start. The thing with fish-mouth is you gotta take it out before it forms. Either grind a heavy bevel on it first or with it in the hardy hole, forge it to a blunt taper with downward angle blows to make a blunt taper first.

[pkrankow]

Well, 1-1/2 inch is pretty big to start. The thing with fish-mouth is you gotta take it out before it forms. Either grind a heavy bevel on it first with it in the hardy hole, forge it to a blunt taper with downward angle blows to make a blunt taper first.

I couldn't source 1 1/4 easily, and ordered 1 1/2, that's all. Making a blunt taper before trying to shape it did not cross my mind.

I guess I don't know what I'm trying to ask.

Phil

[pkrankow]

I ground out the cold shut. After starting I realized it was not from my chiseling, but was the fish mouth, and went back close to 3/4 inch from the end ALL THEY WAY ACROSS! I took a cutoff wheel and cut the end off, then cut an angle to remove what was left. I guess I need to draw the hardy back out next time I fire the forge.
Phil

[stretch]

I learned from Gerry Culberson how to keep out the fishmouth. Starting with 1 1/2 inch is a tall order for one of your first tools. You kind of have to do the blunt end like Grant said and in the process you kind of hammer back to you as you hammer. You start with the hammer hammer out away from you and bring it down and towards you and the blows bring the metal towards you and you upset the metal at the same time so you don't get the fish mouth. Very hard to do with 1 1/2 inch 4140 even with your arm in good practice. Start with a piece of 1 inch cold rolled, it will stay workable longer and you will see it a lot easier and faster than 1 1/2 4140. Your arms being used to something like that is the only way to keep out the fish mouth. It takes practice.

[pkrankow]

Figured I'd post the finished tool after all that. I even used it to cut parts on the 18th century candle holder I'm doing and it works a treat, even if it looks a bit rough.

Normalized and file sharpened. Seems to hold an edge rather well. Fits my hardy in all positions.

I don't have a pic showing how much I cut off though.

Phil

[Nakedanvil - Grant Sarver]

Way to go Phil! Glad you got 'er done. Nice and thin too, I hate it when they're too thick. :D

[pkrankow]

I spent the last 2 or so heats just forging the edge bevel on so it would have a nice shape to it.

It really is easier to use than a less well supported tool or a chisel.

Phil