I found a hydraulic press design in the Zenair Newsletter no. 44 (January 1988). While I could have built that design, I was hesitant because my dies are made of wood and they require equal pressure on all their surface. I had problems flanging using 2X4 instead of 2X6. What happened was that the flange was more accentuated on one side.
So I made a rugged 6-ton hydraulic press:
In the design shown above, I utilized:
Note that the parts in the middle horizontal section need to be spaced a bit (to allow for free movement along the vertical sections. I started by sanding down the vertical 2X8. Then, I thought about just inserting small pieces of scap aluminum (0.025") between the 2X8 pieces... works great!
The jack area is approximately 8-inch high. The pressure area is approximately 4.5-inch high. To go faster and better, I but a 2X8 piece over the die when I use it.
While it took me about four hours to build, I only needed half an hour
to flange 10 ribs (what was remaining in my lot). Still, I will use
it for the other 8 rear-ribs that have to be made, 20 front ribs and also
for the spar.
Prior to making it with 2X8, I had built a model with 2X6's. It
was working well until it broke. That press originally had a 2-ton
jack. I found that jack not to be powerful enough. Because
of this, ribs were "popping" once flanged. These are pictures of
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