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Here is the video for hydroforming rib pieces

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  • Here is the video for hydroforming rib pieces

    finally got around to it... its a bit rough and grainy --- (im grainy too) my first vid. ran out of memory card about 2 minutes before the end.... but no big loss.
    May be kind of boring -- so buyer beware..... :-)


  • #2
    Thanks for sharing you experiences. I would have really liked seeing this before I did my ribs.

    What I am most impressed by is how much better the flange bend is compared to what I got by hammer forming the flanges. And the techniques you used to finish the ribs flanges is really excellent. Really great stuff.

    I assume that for the longer ribs, you would press and then move the rib until the entire rib was formed.

    I used a hand router and I found that I could use the router to cut to the finished shape of the rib from a blank that I formed with a foot shear. The lightening holes in the ribs were routed from a 1/2 inch punched hole. I screwed the patterns for the ribs to a table so the blanks were really rigid located. Like you, I found that I could do up to 4 ribs at a time. For me the time from flat sheet metal to a formed rib blank was maybe 5 to 10 minutes to do 4 pieces.

    The one thing I did different in forming my ribs was that instead of a single flange for the lightening holes, I made forming tools to do an offset joggle. This will tend to flatten the center of the rib during the forming process. I could see how my flanges could have been done with your process and just a different shape to the male forming dies.
    Last edited by S Lathrop; 09-04-2018, 04:30 PM.

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    • #3
      One more factoid I didn't have time for in the video--- (maxed out the memory chip)

      One of my first questions (to myself) was what rubber hardness do I need ?

      My rubber pads are of an unknown hardness (durometer). I bought a horse stall mat at Tractor Supply. Cut it up into 11 by 15 inch rectangles--- stacked them and compared the results
      of that with one of my sold rubber pads (about the same total thickness-)
      I couldn't tell much difference in result--- so I have concluded that the durometer of the two are about the same.
      I believe the stall mats are made from recycled tire rubber---- so my thick pads must be roughly the same durometer as the average car tire.
      Mr. Snap used a thick polyurethane slap to push into. I priced those but they were several hundred dollars. I all ready had these thick pads from when I first built my press
      for another project about 15 years ago. So I just used what I all ready had.

      Also having 30 tons instead of 20 tons helped get the form (and the work) down into the 2-nd pad. The extra 10 tons helped make that much easier !
      Of coarse it will also depend on the surface area of the part. The rear ribs will prob. be easier. The big middle ones maybe harder. (force wise....)
      but easier because of less curvature along the bend lines.

      Tim

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