Forging calculations from round bar to square

[keithf]

I am trying to find a calculation for forging round bar into flat stock. Does anyone know the maths on this. Thanks in advance.
Cheers Keith

 

[Hankins]

What are you trying to figure out?

 

[bdmicarta]

I am trying to find a calculation for forging round bar into flat stock. Does anyone know the maths on this. Thanks in advance.
Cheers Keith

round bar ---------------------------------- rectangular bar
diameter x diameter x .8 x length = width x thickness x length

 

[12345678910]

It's simple elementary school math for volume of a cylinder vs volume of a rectangular bar

but you have to allow some for lost material
and the starting size will determine the ending size,
tiny round will not make big flatbar without lots of upsetting and work

http://www.mathopenref.com/cylindervolume.html

Start with a round bar one inch diameter 12 inches long
1/2=.5

pi x .5^2 x length
3.14 x .25 x 12
9.4 cubic inches


http://www.mathopenref.com/cubevolume.html


then turn it into a rectangle, but you can treat two sizes as "known"
Say, 1/8" x 1.5

total = W x H x L
9.4=.125 x 1.5 x L
9.4=.1875 x l
9.4 / .187 =L
10.8" long

the beauty of forging is that steel is elastic

If you consider full flat grind as a triangle, then you should get twice the width of triangle that you have in a rectangle.

 

[ricky_arthur]

That will depend entirely on how you draw it out.

 

[keithf]

What are you trying to figure out?

I know the size of the material I want toend up with, being 16 " x 2x 1/2". I have a 2" round bar. What length do I need of the 2" round bar to achieve this? Plenty of calcs on how to make square to round etc, etc but not round to square.? There has to be a simple math for this, but hey I cant find it anywhere
Cheers Keith

 

[Stacy E. Apelt - Bladesmith]

Since your desired flat stock width time thickness equals one - the difference is Pi, so you want about 1/3 the final length....about 6" of 2" round stock in this case. This will allow a little loss and wiggle room.

 

[Karl B. Andersen]

There are all kinds of online steel weight calculators.
What is also important is your forging method.
It's amazing how wide a piece of round stock can get when you draw it laterally.
Your flat bar you want weighs 4.528 pounds.
A round bar 2 X 5" = 4.456.

 

[keithf]

Hey thanks guys. Think I'll go an average of Pi and the weight conversion.
Cheers Keith