You need the larger material size (not thickness, area)to resist it wrinkling and collapsing so it stretchs the inner material to the shape. Basically you want the part of least resistance to be the inner metal stretching into the bottom half of the die.
When its pressing, the outer edges start to wrinkle up. If the base of the die had a wide flat lip around the edge, and you have a thick steel plate with a hole in the middle, you could clamp the disc down with only the hole for the top die exposed. When pressing, this would draw the material in under more even tension and help prevent the wrinkling on the edges from starting.
Stuff made here has made a pretty in depth video at the trial and error method of press forming. It's "How I made steel toe crocs with wood" if you're interested. He stopped the the material folding over itself by clamping it down really well.
@@house-ofhoon 0 is very soft but will age harden some on it's own, it may even work harden from the press, not really sure, it's not readably available in small quantities. You can easily anneal (soften) aluminum with heat, no doubt lots of TH-cam videos on it.
I know exactly what this is; we call it "flowering." You need to support the outer edge of the blank with downward pressure or it will take the path of least resistance and begin to wrinkle. In extreme cases these wrinkles can cause blowouts. A more substantial lubricant will also help.
I wonder if cutting v shaped reliefs into the outer flange almost up to your outer diameter of the hemisphere would give that wrinkling stress somewhere to go. Unless you NEED a flat flange around the hemisphere?
You need the larger material size (not thickness, area)to resist it wrinkling and collapsing so it stretchs the inner material to the shape. Basically you want the part of least resistance to be the inner metal stretching into the bottom half of the die.
Cheers mate
When its pressing, the outer edges start to wrinkle up. If the base of the die had a wide flat lip around the edge, and you have a thick steel plate with a hole in the middle, you could clamp the disc down with only the hole for the top die exposed. When pressing, this would draw the material in under more even tension and help prevent the wrinkling on the edges from starting.
Cheers mate
Stuff made here has made a pretty in depth video at the trial and error method of press forming. It's "How I made steel toe crocs with wood" if you're interested. He stopped the the material folding over itself by clamping it down really well.
Cheers mate
Perhaps a softer temper aluminum
Range generally 0-7 with 0 being the softer.
That would likely have helped!
@@house-ofhoon 0 is very soft but will age harden some on it's own, it may even work harden from the press, not really sure, it's not readably available in small quantities. You can easily anneal (soften) aluminum with heat, no doubt lots of TH-cam videos on it.
i would try doing a deep drawing die design i would love to see that send me a link if you make one
Thanks for the idea mate! I'll definitely try that when I get time 😁
I know exactly what this is; we call it "flowering." You need to support the outer edge of the blank with downward pressure or it will take the path of least resistance and begin to wrinkle. In extreme cases these wrinkles can cause blowouts. A more substantial lubricant will also help.
Thanks for your help mate!
What capacity press are you using?
It's a 20ton press mate 👍
I wonder if cutting v shaped reliefs into the outer flange almost up to your outer diameter of the hemisphere would give that wrinkling stress somewhere to go. Unless you NEED a flat flange around the hemisphere?
That's a very interesting idea mate! Cheers!
The outer edges are wrinkled because they need to be shrunk...
Cheers bro
What infill do you use for the printed pieces?
90% with a heap of walls. It is 100% solid
Shouldn't the top die be less radius per the thickness of material?
Excellent question!
@@house-ofhoon As discussed in messenger, you need to allow for the thickness of material to prevent the wrinkles...
Was thinking the same thing - general rule with pressing things is you need at least one thickness of clearance between tools.
You can use soft rubber for the bottom die.
Yea soft rubber works great. We used that technic at Tickford Racing for a few parts
Looks like your making ash trays
It very well could be! Except I don't smoke haha
can you measure the maximum pressure used while pressing?
Unfortunately, my press doesn't have a pressure gauge
@@house-ofhoon thank you for relpying. Is there a way to somehow feel if you were close to the maximum output?
@@house-ofhoon what is the maximum output of your press?
My press is 20tons and it was definitely nowhere that. It pressed it relatively easily
@@house-ofhoon thanks