Machined Steel Rule Die

So we do a lot of die cutting for our soft goods and a widening catalog of very specialized bits of camera gear. All this stuff is cut with steel rule dies. They aren't so expensive (~$180 for the smaller ones), but I would like to make some of these in-house for the really niche projects and prototyping. We're talking 1x2" max size parts, with a lot of curves. Material being cut is mostly 3M Bumpon grip and some 5-7oz leather.

In a pinch, I've done aluminum ones before, that last about 5 (poor) cuts before they fail. They literally just were a thin wall of the desired profile and a chamfer on the top.

Curious if anyone has done anything like this and what sort of parameters you use - material, wall thickness, chemfer/bevel angle, etc. Can they hold up for a few hundred cuts?

We cut lots of automotive gaskets using steel rule dies. We don't make dies in-house but we occasionally replace/repair bits of them. The die company we work with uses laser-cut birch ply for the base and has some kind of CNC bender for the rules.
Our die guy gets supplies from Wagner Die Supply. I have also bought parts from them to modify dies. They have a pretty good site with a lot of information about rules, punches etc and I imagine they would be willing to advise over the phone. This guide by them might be interesting to you, it has info on rule thickness, material, bevels etc: http://wagnerdiesupply.com/Images/Gen-SteelRule-Guide-2016.pdf

Reading through your post again, sounds like you want to machine the dies complete from solid? Might be easier to make bases only then bend premade rule that can be slotted in? Being able to replace rules is a plus for us but I imagine our material is tougher on dies and higher volume than what you are planning on doing with shop-made dies.

Yeah i do it, simply mill them out of 02 and harden. Keep the formed rule height to a minimum, Mill the bevels with in my case a hand reground spot drill as a chamfer mill with my desired angle.

Key thing with life and part quality is what you cut into material wise. Bevel angles and heat treat are also key. I like harder materials for anvils, default in the industry is plastics, i find better results with cutting on - against a surface ground anvil of mild steel. You really want to be running the rule die block in something akin to a die set, you want depth - pressure really well controlled and you want it to hit the exact same spot on the anvil. If your chewing the anvil up, there goes your part quality and die life. Standard clicker style presses are great for shoe parts and most gaskets, when using heavy clicker style rules, you want high quality parts with sub 1/4" features, you need it guided better. You want top end quality, you have to run it in a die set not a std clicker press. Have had great success in the multi 10K parts range running on a flypress. That was a semi brittle plastic molded part we die cut some varied and complex features in, got around the brittle issue by preheating the plastic.

Bevel angle needs some experimentation, but as your milling it you can make it single sided, makes the parts a nats harder to eject, but edge quality goes through the roof!

Bending rule in ply for smaller parts just does not work well in my experience. Fine for jigsaw puzzels and a lot of die cut work in the print and larger gasket trades, but lacking if you want lots of small very sharp cornered features and gets a real pain if you also want odd shaped holes.

I have done a lot of die cutting with regular steel rule dies and have sold lots of presses. I have used a few machined dies in rf cut and seal tools. I have seen many .machined dies for your type of job. i have seen them were a rough shape was assembled from strips and then machined then i imagine they were disassembled for heat treating. I have seen small ones that were machined from plate but smaller foot print. i am wondering if you can induction harden just the cutting edge?