Thanks, Brian.

I used to have some bismuth alloy but I lost it somewhere around here.

I am going to have to do some more research about bending/forming pipe or
tubing as I don't know nearly enough about what I need to do what I want to
do.

Cass


"Brian" wrote in message
...
You will probably need an internal mandrel for 1" radius on that size
stock.
What I think would work is the Cerametal stuff that melts at very low
temperature.

Brian


"Cass" wrote in
message
...

Thanks, Jenson.

I have 3 tons of 3", 416 s.s. So, I have plenty of stock to practice
on.

What I am trying to do does not have to be perfect but it is necessary
that
the tubing of roughly 3/4 to 7/8 take 180º bends within very sharp
radii*.

Thanks

Cass



*Note to the little ankle-biters, radii is the plural of radius. I know
that you will look that up. Cacti is the plural of cactus. Anii is the
plural of ass-holes that I just coined and it seems appropriate to a few
responders.
Need I give a lesson on penii?





"Roy Jenson" wrote in message
...
As much as I liked the dice discussion.................

Making the dies in a lathe works fine but has a few practical
problems. The shop I worked at made many of them.
Things to consider:

1) the starting blank need to be a solid chunk at least 1.5x
times the diameter of the tube and the full diameter of the bend.
This is not an issue for a 1/2" tube on a 2" radius but a 2"tube
needs a 3" thick slab around 12" in diameter. (assuming a 3d
bend) Youmay be able to get by with a welded up or bolted up slab
but it is fragile and tends to leave nasty tooling marks in the
tube.

2) the groove should be round. You can approximate this and file
out the rest but the good way is to use a spinning tool mounted
in the tool rest. It has a pivot, a long arm, and a cutting tool.
The blank is hollowed out, the pivot point is moved to the exact
centerline of the tube, and the arm is rotated back and forth.
Works slick the tool ran around $1000

3) long term use requires heat treating. A whole 'nother story on
big chunks of odd shaped steel.

Someone posted an excellent set of links to tube bending theory
in the last few weeks. Take a look at those.

Cheers.

Cass wrote:

Thanks, Ernie.

Is there any practical reason one can't simply make what they need
on
a
lathe, other than the proper dimensions?

Cass

"Ernie Leimkuhler" wrote in message
...
In article , Cass
wrote:

Does anyone know where I could research for pipe bending dice
that
are
used
either for manual or hydraulic bending?

I guess that I could make some on the lathe but not sure of the
dimensions.

Thanks

Cass




The cheapest method is to simply buy a 12-ton pipe bending set
from
Harbor freight.

I know of no simpler of cheaper method of getting the die sets.