Quick forging Question

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unky_gumbi

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Aug 28, 2009
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When forging from round stock is there a rough guide line for blade hight/thickness to stock diameter? Say you wanted to make a blade that was 1.5 inches high and 1/8 thick what size round stock would you start with? This is a hypothetical question, just curious
 
for a rough guide just use the area of the face of the bar

pi * R^2 for the circle and then use rectangular area w * h

so for 1/8 by 1.5 you've got an area of .125 * 1.5 = .1875, so R = sqrt(.1875 / pi) so R = .25 so if you could forge with no scale loss you'd want half inch round bar stock. Since you're going to want wiggleroom for scale loss and grinding, bounce it up a size in the stock and go for 5/8ths or 3/4 round.
 
Thanks for the answers, surface area make sense to me the never thought about scale thought so that a good heads up and should shorten the learning period a litle bit
 
That's all fine and good, IF! you can go directly in a lateral direction with your steel.
Inevitably, depending on your forging style, anvil and hammers, you're going to move that steel lengthwise as well.
Then, your formulas for area aren't going to work.
Start with as large a piece of steel as you have the strength to knock flat, then gradually reduce the thickness and width of your resultant bar as necessary to arrive at the dimension you want.
It's easy to get something small out of something large - not the other way around.
 
Forging rounds is a challenge for me, it's fun though depending on how tired I am :p

I've got 5/8" I use for 90% of all my round forging needs, it gets me the size blade I usually make.

My ninja monkeys don't cypher so good :p
 
So it looks like 5/8-3/4 would be a good place to start, once I get the forge built and it warms up here:rolleyes: and I get a good amount of practice on the non coated rebar.
 
Just get some 2.5" W2 round stock from Don Hanson and just slice off a half inch or so from the end so you have a cookie and forge that into your knife.
 
As a general rule I use, you can generally double your diameter of the stock your working with, i.e. 3/4" dia = 1.25" - 1.5" wide stock 3/16 - 1/8" in thick. I generally use 5/8" - 3/4" W1 round. I start forging the point first by tapering the end rather obtusley, and make it look like a pencil point, then forge it flat and start drawing the blade out both ways. then I'll work the ricasso and the tang. PAY CLOSE ATTENTION TO THE RICASSO! The rest of your knife is built on it! Then after that I'll begin forging in the bevels. and next normalize 2x then slow cool anneal. in dry wood ashes and vermiculite.
hope this helps :D

Jason

BTW I hate lazy bastards too :thumbup:
 
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