Sam Perakis Posted October 22, 2018 Share Posted October 22, 2018 I've been looking all over for a diagram of how the screw and ram of a fly press are attached. In essence: how is the axial force of the screw delivered to the ram without rotating it? I've looked all over Google Patents, different vendor websites, etc. to get a good look at the ram-screw junction, but I don't see what's going on in there. I have a post drill and I assume that it's something like the junction for the downfeed screw. i.e. the screw has a turned down section with a shoulder that goes over a captive nut which allows the screw to push and pull on the spindle but also allows the rotation of the feed screw and the spindle to be independent. Does anyone have a good diagram for this? I'm looking to copy the geometry into a shop-build punch press kind of like the Roper-Whitney's using some threaded rod. Thanks! S Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted October 22, 2018 Share Posted October 22, 2018 Perhaps you should have a look in the press section? I will relocate this for you Quote Link to comment Share on other sites More sharing options...
Sam Perakis Posted October 22, 2018 Author Share Posted October 22, 2018 Thanks Steve, For reference: This is the patent that I've found that makes the most sense: https://patents.google.com/patent/US975591A/en?q=screw&q=punch&inventor=william+whitney&oq=william+whitney+screw+punch Basically, the punch ram and the screw have ends that form opposite races for a ball bearing. The ram is retained with pin that goes all the way through the screw and a nut on top that allows the screw to rotate freely with respect to the ram (the ram in this case carries a punch, but the principle applies to a fly press). This is all well and good, but I would have a really hard time machining a ball groove into these parts. If I can't find another solution, this is what I'll have to do. The mechanism I mentioned from my post drill doesn't provide for a lot of bearing surface - I'm afraid I would start bending or breaking parts which is dangerous when there's 20-30 tons involved. Quote Link to comment Share on other sites More sharing options...
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