Subject: Re: Mild-steel cracks

From: Peter Beky <[email-masked]>
Date: Mon, 16 Sep 1996 19:48:43 +1000

Tom,

Another common forging fault is over-rolling when drawing a taper.

The method should be in a round bar with a round taper...draw the stock out 
in square section; work from the tip back, turn it over 90 deg working 
from the tip back again so there is the start of a square taper, then over 90 
deg repeating till the stock has a square taper of about the right length, 
then take the corners of the taper off so that it is octagonal, then round up.  

The same method goes for square section also.

Peter.

---

From: Noel Gregg <[email-masked]>
Date: Mon, 16 Sep 1996 18:20:13 +1200 (NZST)

At 18:15 15/09/96 +0000, you wrote:
>On 12 Sep 96 at 6:29, Tom Alexander wrote <snip-snip>
>
>>After repeated heating and
>> hammering, the end of the thin section develops hairline cracks and
>> eventually breaks off, spoiling my day and disposition.
>> 
>> Question 1: How do I prevent this from happening?
>
>One of several things could be happening here.  You could:
>
>Be attempting to forge at too cool a temp which will result in 
>cracks.
>
>Be forging at too high a temp, which can burn and crack the metal
>
>Be heating your metal in the wrong part of the forge.  A lot of 
>newcomers shove their metal down into the fire at an extreme angle.  
>This puts the bar in the oxidizing portion of the fire and after 
>repeated heatings the metal will tend to crumble or crack.  Be 
>certain to heat in the neutral or reducing section of the fire and 
>don't work below orange or at a temp that shows "sparkles".
>
>> 
>> Question 2: Once it starts, is there any fix?what to do 1: cut the end
with cracks in it off then forge back to the size then let it cool on the
floor over night. then heat until bright red and temper by 11/2"of forged
bar in the water and let rhe colour run down the bar until the blue meets
the strawand let cool finnish.noel gregg.
>> 
>
>Nope, it's toast.  Cut it off and try again.
>BTW try drawing the taper out over the horn of your anvil.  The horn 
>will act as a big bottom fuller and reduce the number of heats 
>required to draw it out.  Finish the taper up on the face of the 
>anvil.  Saves you arm, too.
>
>Best of Luck, we all go through it....
>
>=================================================
>Franklyn D. Garland                         
>The Celtic Knot Forge                       
>[email-masked]                                 
>http://www.mcs.net/~frnklyn/homepage/
>For Public PGP key, finger [email-masked]
>=================================================
>
>
Regards

Noel Gregg