predicting springback
 

Im looking for info on predicting springback of 6061-T6 aluminum.
Specifically I want to know the punch radius for a part with a 1.08 r. Also I
need the springback factor for bending a 90 degree angle with a .18 r at the
bend.

forgot to add that the material is .025 thick

Wwj2110 wrote:
forgot to add that the material is .025 thick

Find yourself a book on Strength of materials. From the formulas find
the yield point and modulus of elasticity. Calculate the over-bend
needed, set it up and measure the results. Then adjust it until you get
the correct results. G
Bugs

6061-T6 aluminum age hardens. 5 year old stock will have about double
the springback of fresh (weeks) old stock. Net: you will have to fiddle
with your bends on each run. Plus, your bend radius is 40x and 7x the
material thicknes, you will have difficulty gettting any kind of
consistentcy in the bends since you are not pushing the material to it's
yield point.

Wwj2110 wrote:
Im looking for info on predicting springback of 6061-T6 aluminum.
Specifically I want to know the punch radius for a part with a 1.08 r. Also I
need the springback factor for bending a 90 degree angle with a .18 r at the
bend.

"Wwj2110" wrote in message
...
Im looking for info on predicting springback of 6061-T6 aluminum.
Specifically I want to know the punch radius for a part with a 1.08 r.
Also I
need the springback factor for bending a 90 degree angle with a .18 r at
the
bend.

It's been over thirty seconds (20 years) since bashing aluminum into
compound irregular shapes... but I think t-6 must be annealed first in order
to get any shape change at all. So you soften the 6061 and keep it frozen
until brought to the forge. Then you smash it to shape with no springback at
all because it's mush. When it sits for a few days it regains its
strength... I think.

Wayne

The chart that I use at work doesn't even list 6061-T6, only 2024-0, 2024-T,
2024-W, 7075-T, 7075-0, and 7075-W
Lane

"Wayne Lundberg" wrote in message
...

"Wwj2110" wrote in message
...
Im looking for info on predicting springback of 6061-T6 aluminum.
Specifically I want to know the punch radius for a part with a 1.08 r.
Also I
need the springback factor for bending a 90 degree angle with a .18 r at
the
bend.

It's been over thirty seconds (20 years) since bashing aluminum into
compound irregular shapes... but I think t-6 must be annealed first in
order
to get any shape change at all. So you soften the 6061 and keep it frozen
until brought to the forge. Then you smash it to shape with no springback
at
all because it's mush. When it sits for a few days it regains its
strength... I think.

Wayne

It's been over thirty seconds (20 years) since bashing aluminum into
compound irregular shapes... but I think t-6 must be annealed first in order

I took a small piece of 6061-T6 about 3/16 square and tried to bend it.
It broke without bending very much. 1100 alum bends quite nicely!

chuck

On 20 Jan 2005 16:38:13 GMT, Charles A. Sherwood wrote:

It's been over thirty seconds (20 years) since bashing aluminum into
compound irregular shapes... but I think t-6 must be annealed first in order

I took a small piece of 6061-T6 about 3/16 square and tried to bend it.

How do you bend something that's 3/16ths of an inch square? How do
you hold something like taht? Or did I miss something?

I took a small piece of 6061-T6 about 3/16 square and tried to bend it.

How do you bend something that's 3/16ths of an inch square? How do
you hold something like taht? Or did I miss something?

It was 3/16 square and a couple inchs long. I made a simple bender
by putting a V block on my arbor press an putting a wedge on the ram.
Works surprising well for many things. I can also put the wedge and
V block in my kurt vise and bend things that way. Same results

chuck

On 20 Jan 2005 20:43:49 GMT, Charles A. Sherwood wrote:
I took a small piece of 6061-T6 about 3/16 square and tried to bend it.

How do you bend something that's 3/16ths of an inch square? How do
you hold something like taht? Or did I miss something?

It was 3/16 square and a couple inchs long.

Sorry, I was picturing a really, really small cube and couldn't
imagine what you were saying.

I made a simple bender
by putting a V block on my arbor press an putting a wedge on the ram.
Works surprising well for many things.

Yes, I use that frequently. I also control the radius of the bend by
using a piece of round stock of appropriate size rather than a wedge.
Still haven't found a way to keep the top edge of the V-block from biting
into that which I'm bending, but it hasn't been critical yet.

Dave Hinz

Yes, I use that frequently. I also control the radius of the bend by
using a piece of round stock of appropriate size rather than a wedge.

Interesting idea. I tried it before but I just used a rod which was
free to move so it was difficult to locate the bend accurately.
I really want a diacro #1A bender!


Still haven't found a way to keep the top edge of the V-block from biting
into that which I'm bending, but it hasn't been critical yet.

I was thinking of trying some soft copper sheet between the block and
the work. Seems like it should help.

On 20 Jan 2005 21:32:05 GMT, Charles A. Sherwood wrote:

Yes, I use that frequently. I also control the radius of the bend by
using a piece of round stock of appropriate size rather than a wedge.

Interesting idea. I tried it before but I just used a rod which was
free to move so it was difficult to locate the bend accurately.
I really want a diacro #1A bender!

It's a free-hand operation, yes. I solved the lack of accuracy by
leaving both ends long and making them the length I wanted _after_ the bend.
When there are things I can't control or predict, I resort to that.

Still haven't found a way to keep the top edge of the V-block from biting
into that which I'm bending, but it hasn't been critical yet.

I was thinking of trying some soft copper sheet between the block and
the work. Seems like it should help.

I've got some .032" or so copper sheet, I'll try that next time. Thanks
for the idea.

Dave

snip

Still haven't found a way to keep the top edge of the V-block from biting
into that which I'm bending, but it hasn't been critical yet.

snip

The shop I work at does all sorts of metal fabrication and we run several press brakes. To keep the part from biting into your V-Block, you need to break the sharp corner. All of our lower forms on our press brake tools have radii on the upper corners to allow the material to slide, the deeper the draw the larger the radius. We actually grind a radius on the forms on a surface grinder, breaking it by hand doesn't produce a large enough radius fast enough for us. Typically 1/32 minimum.