You can get away with a pretty floppy bench but you will be happier with a sturdy one. I'm not sure there is an upper limit- sturdier is better. All the force is on the down-stroke and having some "feel" provided from a sturdy bench is better.
^^^ This. Put a lower shelf on it and weight it down.
I went the other route when I built mine, and have a post from floor to ceiling.
Either you went full Mondo on the wrench used on the lag screws or you missed the studs.
The other thins is that you don't need the strength of a lag screw. A couple of #8's will do just fine.
If you don't have a stud finder use a magnet to find the drywall screws. Those indicate the stud locations pretty surely
An option you might consider is to put a strap along the wall ABOVE the bench so it presses down on the rear edge. This gives you a neat way to hold the bench in place while locking it to the wall and at the same time acts as a back stop to avoid small parts slipping down the gap. It can also be used to mount a neat tool rack and shelf along the upper edge of the strap if you use a wide enough one. Something like a 1x6 would work well as the wall strap. And another 1x6 supported by a few small angle brackets as the shelf.
As folks are saying most of the force is needed on the pull/down stroke and the only force on the lift is to extract the cases from the sizing die. None of the other dies or steps produce any significant up travel load. So just some goodies on the bend will load it down well enough to stay in place nicely.
Something you might consider instead of the C clamps is to drill for a pattern of holes in the bench and fit it with top hat nuts from below in 3/8" size. Then drill matching holes in the press mount plate. This lets you bolt the plate to the bench instead of C claps which you WILL snag your leg on and hit your knee cap. It WILL happen and it WILL make you say some nasty words that children should not hear.
And best of all that same pattern of four holes can be used with a second mounting pad to hold a nice bench vise for jobs that need one. Or any other tool that you wish to be held solidly in position. And when you get a new progressive press at some point you can use the same holes and plate dimensions to bolt that down too. It's just so neatly flexible and adaptable and so much nicer than clamps that keep trying to do bodily harm to you.
The wall,isn't covered. There's no way I missed the studs. I'll try some screws to cinch her up.
I was gonna also c clamp my vise to the bench, but I like the idea of using top hats instead of clamps. I'm guessing you speak from experience? Lol
What you have posted here sounds pretty solid. Mount everything up and give it a whirl, see if and or how it's moving and modify. If you don't want a shelf have you considered an angle brace from the outer edge and wall framing? A minor amount of movement isn't a deal breaker.I tried without,success to lag the whole bench into the wall. I drilled through the metal frame and only one lag held.
Not sure if I just hit a weak spot in the stud 3 times? Still puzzled.
It's basically just a typical countertop on the metal frame. My press will NOT be mounted directly to it. The plan is to glue together 2 3/4" pices of plywood (12 x 20") and permantly mount the press to it, and when needed, c clamp the press on the corner of the bench. That should give me stability.
My bench is also all purpose so I don't,want a press mounted all the time



























