Which one is better? PUNCH PRESS VS LASER

Gunner basically has it right, but it really depends on the kind of work yo u're going to do. If it's straight lines and round holes (or square holes), then a punch press is much faster and somewhat cheaper to operate -- but t hat depends on what kind of laser you'd be getting (fiber lasers cost more up front but operating cost is much less than for CO2). And that, in turn, depends on what you're cutting.

I wrote about a FAB 40 shop (IOW, top-ranked) a few months ago that has the latest automated punch presses, CO2 lasers, and fiber lasers. The owner of that shop discussed why he's still buying fancy punch presses when it seem s like the whole fabricating world is going to lasers, and where he uses ea ch.

Maybe you'll want to read the article and see what he has to say:

And only punches can do louvers, c'sinks, tapped holes, and other formed features.

Gunner Asch on Tue, 29 Nov 2016 22:37:20 -0800 typed in rec.crafts.metalworking the following:

Punch presses require punches. Those can get spendy to make and replace. The time needed to make one needs to be added to any "production time" when costing out a project.

But lasers do not need dies to make the holes. So there is that savings. OTOH, how long does it take to program a hole like one the punch press can knock out'?

Which is the issue: complexity of the hole, vs the number to produce, and the total time to make up a run.

-- pyotr filipivich "With Age comes Wisdom. Although more often, Age travels alone."

I was just a company here that works with titanium sheet. The description of their laser cutters sounded like a love story. There's no tooling cost, and they can make prototypes or final products in just a couple days. This fast turn around is how they stay in business.

Having programmed both punch presses and lasers, I'd say overall the laser was faster, and that was with software 25 years ago. To nibble a window with a punch press requires selecting a punch that will maintain better than 50% overlap per nibble. Laser doesn't have that issue. I'm sure software is more sophisticated these days, but I'm out of out of touch. Maybe punch selection is automated today?

Cluster punches will produce arrays of holes faster than a laser, but a laser in most materials should be able to produce large cutouts faster.

Punch presses, as noted, can perform a wide variety of forming operations. Which machine, depends upon the sort of work a shop is doing. For a general sheetmetal shop having both offers the best of both worlds.

Jon

Has anyone on the group ever made a bolt driven chassis punch? I want one for the common as dirt IEC 'C7' connector used for computer power cords. They sell for around $600, which is out of the question.

The closest I've made is a bolt driven die set for repairing a tarp shelter cover with 3/8" brass grommets. Hardening and tempering steel to the right degree to cut metal is tricky, and grinding punches and dies evenly a job for a surface grinder unless you have a good hand and eye for a belt sander.

I used a D connector punch for a while on a job and didn't have good luck with it because the tightening torque misaligned the punch and die, despite the guide pins and oil on the screw. I wasn't the first user.

Usually I grouped the connector cutouts onto a flat rectangular panel that fit in the milling vise and hogged out an oversized clearance hole for it in the formed chassis.

You could cut out the opening in a slightly larger piece of steel and clamp it on as a filing guide.

--jsw

A fabrication company I use recently sold their CNC punch press and

which they are much happier with. They said there was little that the punch press could do that the laser couldn't and those few items they could do with an old manual press or farm out on the odd occasion it was required. For them the laser rules over the punch press.

At that price, and that big a hole, you'd be well advised to use a hydraulic puller (about $100) instead of wrench-on-screw. Off-the-shelf punches for double D and rectangle shapes might work (depends on how much the connector's flange conceals).

This IEC connector fits a rectangular hole, can be punched round and nibbled (not ideal, but workable)

I do not run either, but If you need to nibble a hole then the advantage goes to the laser. For a one shot and done hole, advantage punch.

Lasers have a cost per inch of cut, plus a cost per pierce. Punches have a cost per punch.

For small standard size holes a punch is most likely best, when holes get big (excess tonage) or odd shaped (expensive tooling) then use the laser.

They make punch presses now with a laser built in, punch the easy holes laser cut the rest.

Randy

Remove 333 to reply. Randy

I have cut dozens, if not over 100 with an Audel hand nibbler. I've worn out three of them in the last 45 years, plus a half dozen of the crap ones that Radio Shack used to sell.

I had the Greenlee 731R rectangular relay punch for P&B relays. It, and over two dozen other Greenlee punches were stolen.

When an Adel nibbler starts to dull I remove the compressed washer, spring and stripper plate, disassemble it and grind the cutting edges. I leave the stripper off when reassembling it so it doesn't mar the surface around the cut and gets into tighter spaces.

They are slightly harder to use because the stripper spring helps retract the punch if it isn't oiled, such as for modifying assembled aluminum chassis boxes I can't easily wash.

--jsw

The frames broke on these, near the die. I wore out a lot of punches, before the frame died of metal fatigue. I used to do a lot of prototyping, with hand tools. Trimming fiberglass circuit boards to fit into a case was the worst for wearing out the tool.

I've worked at a few places, notably Mitre, that had good facilities for both electronic and mechanical prototyping but that wasn't the case at smaller startups developing some new idea on a tight budget. I've nibbled, filed and sanded a lot of circuit boards to size including the mechanical-fit models for the Segway balance sensor assembly. At one place when the Dremel died I cobbled up a pump drill to finish a circuit board. Unlike a bow drill it applied no side force to the fragile carbide bit.

For that price they could at least have found a prettier smoothed river stone for the weight.

Do those rely on the inertial force of the spinning stone to work? Wind 'em up, push down, and they spin until wound the other way. Rinse, repeat?

Momentum. (It's early.)

Yep, push down, let it rise, push down...., while steadying the top end with the other hand. It's less awkward and tiring than a bow drill. Since it spins both ways a blunt spear point with flats on the edges works well for the drill bit, and is easy to resharpen. You could drill your first counterweight with a bow drill that doesn't need one.

When I was little we moved into an 1830 house that had a chest of those old "cordless" tools, which I used until I was old enough for power tools. The tricky part was learning how to keep them sharp.

--jsw

Just make one...

This guy has some unique ways to have "fun"....

I wondered about the bit end. Dual flats, eh? Spoon bits are interestingly shape, too.

Cool article.

Ah, Eric Sloane: a great author with a bevy of very good books under his wing. I have a copy of his _A Reverence For Wood_ and it's marvelous. George Sturt wrote _The Wheelwright's Shop_, which is also an excellent and detailed stroll through yesteryear.

As a Neanderthal wooddorker, I have either used, and/or made, dozens and dozens of old tools like that, but never a pump drill. I made fire with a bow drill just once, then immediately declared the end of my enthusiasm for them. They're a lot of work. Those pipe augers look like a whole lot more of the same. Ugh! Breast drills are a joy to use, compared to pumps, bows, braces, Yankees, and little egg-beaters. Ditto post drills.

And now, with metal, I'm finding much more ease with a drill press. Who'd have guessed? A mill is a pain to set up, comparatively, but is sure is accurate. Having come from a woodworking past, my time with Glenn in his metalworking shop was a real eye opener on most fronts. That's why I'm here: to continue learning with all you good teachers.