Leaf work, cracks at top of stem

[Matthew Roy]

So, I am new to iforgeiron and I’ve only been blacksmithing for a couple of months. I’ve been working a lot on tapers and drawing out, and in the last couple of weeks have tried about 10 or so leaves.

    The problem I am having, without fail, is that the stem seems to twist and crack right at the base of the leaf when I start to flatten it out.....almost every time.

Does anyone have any suggestions as to what may be causing this? Thanks!!

[arftist]

read about the notch effect.

[Matthew Roy]

Thanks, will do...

[arftist]

To avoid the notch effect a transition in size should be gradual and smooth.

.

[Judson Yaggy]

Looks like you need to grind a slightly bigger radius onto the corner of your anvil.  Either your hammer or the anvil edge is shearing off a little portion of the shoulder of your workpiece and smooshing it down into the neck area.  This causes what blacksmiths call a cold shut or engineers call a stress riser.  Thus the crack and breakage.  

A few hundred more pieces and you should gain the hammer control to avoid this without tool alteration.  Either way works, but the key is practice, practice, practice...

[Kevin Olson]

Yup. You have to set the leaf down over a bigger radius. I had the same problems with my leaves.  Build a hardy tool with an edge with a  radius of a pencil. It looks way too round but will work. Like Judson says, practice.

[C-1ToolSteel]

Also, make sure that you aren't stressing the stem when it is has already cooled down to a black heat. It is an easy mistake to make, because the thin steel cools down very quickly while you are working on other parts of the leaf. If you are using high-carbon steel, this is even more of an issue.

[Joel OF]

Hi, I started a thread on this a while ago when I finally figured out how to avoid this problem. I posted step by step pictures in it and you might find it's what you're after.

 

[(M)]

Keep it HOT! Dont forge below a bright red.  The way I was taught to make leaves is as follows: taper, then half face blows quarter turn each time to get the neck.   After this, flatten into a leaf shape.  Once i have somewhat of a good neck, i like to use a smaller hammer and neck it the rest of the way and finish it.  

Also might want to put a bigger radius on the edges of the hammer or use a rounded face to make bad hits less obvious.  

Best of luck!

I'm a newbie myself and only know anything at all cause i have had the priveledge of free tutelage of an experienced blacksmith.  I have made i think 4 succesful leaves, and i have it down to a system.  Keep it hot! 

[C-1ToolSteel]

I went to make a leaf recently on someone else’s anvil. The edges were sharp, but I figured I had plenty of experience to be able to work around that issue. Not so. The dreaded cold shuts that I had plagued my newbiness so long ago had come back to haunt me! After several subsequent failures, I finally found the radius block...

Dress your anvils!!!