cnc welding.... $2.50/pop !!

I didn't see a $99.00 belt skimmer on their site.

-- Tom

I don't know why someone would tell you that. Welding can save bundles of money in lots of applications. And it can help you make stuff you just couldn't make any other way.

KG

True, but in the right context, etc. In the context we were dealing with (essentially parts/ops hand welded at a bench), compared to all the other operations, the welding costs just swamped everything else. His advice was to find a way to avoid welding.

In a pure cnc-robotic welding scenario, yeah, it proly saves a bundle, but no doubt with hefty capital investment.

I bid welded assemblies for years. Normally had the estimated weld time within a few percent of the actual time.

If you hand welded things (usual fixtures and such) you have a fixture build cost, a fixture load time, hand positioning time, and the actual arc on weld time. Add them all up and you get a cost. The capital cost for the welder was trivial: figure a $5000 mig welder that runs two shifts for 10 years, cost is $.12 to $.15 per hour.

When you robot welded things, the fixtures had to be just perfect, usually cost 5x to 10x the manual weld fixtures (if not MORE!). The first big saving is if you double fixtured it on a rotary positioner, your load/unload was done while the robot was welding so load cost was zero. Of course that doubles your fixture cost.

Weld time (arc on) is just slightly faster for the robot so an inch of weld was pretty much the same for robot vs manual. But the time to position for the next weld is MUCH faster with the robot. How much faster was dependent on the product but if you are trying to minimize distortion by welding opposite sides alternately, it is a HUGE speed increase.

Robot hourly cost was pretty reasonable: same 2 shifts x 10 years was $2.50 an hour. Consumables cost was much higher than that.

Running the plant was much like PV's comments: When you manually welded a product you fabricated the parts, sent it to welding, it would reappear a week (or more) later. With the robot it sucked parts as fast as the rest of the place could produce. It sometimes felt like the robot cell was a huge bird nest with a batch of hungry chicks, all with their mouths open. Just shovel parts in as fast as you can. It really picked up the pace.

BTW: to do an assembly made from 1" x.049" tube with lots of full coped joints, full 360 degree welds, reasonable access to all sides of the weld, and quantities high enough to run the robot for 40 to 60 hours per setup would price out (what the customer saw on his invoice) around a dime per welded joint.

What kind of crash? Re-boot type crash, or damage-crash? First I've heard.

Inyone else??

So this site's price, at $2.50/weld, seems perty high, eh? On 1/8 diam.

No. I'm talking about just plain stick and mig welding by hand. Imagine something simple, like a 2" dia x 24" long shaft with a 4" diameter flange on the end. A good welder could stick a sawn bar and a burnt-out plate together a lot faster and cheaper than you could rough two inches off of the OD. Boxes and flanges and brackets and tombstones and fixtures, and things with funny shapes that you don't have the time or the money to forge or cast, can often be done well and cheap by a good welder. And with nasty materials, though the welding is surely more expensive, it can sometimes pay for itself just with the savings in tools and inserts it would take to rough the shape from solid.

And, if you work with a lot of cold-rolled steels, you'll find that a few bucks spent on normalizing after welding can make even the machining part of a job easier and more reliable.

KG

WARNING, THIS LINK / SITE CRASHED MY COMPUTER.

WARNING, THIS LINK / SITE CRASHED MY COMPUTER.

Didn't do anything to mine.

-- Tom

Maybe, maybe not. The price I quoted was for a Mig weld on reasonable sized and reasonable wall tube. We did 200 ATV carrier rack per day, per robot.

The site you quoted was for a Tig weld with filler, a process that is normally 1/10 as fast as Mig. Since all of this is time per piece and parts per hour, it will cost more. If the only way to do the part is with a Tig weld, then that is the sort of price you will need to pay. Whether it is worth that much to the client is up to the client. But yes, $2.50 still sounds expensive!

Miro$oft IE error message IIRC, 'error encountered, program forced to close' normally means crashed IE, IMHE the best tactic when this occurs is to close all other open IE windows and reboot. I realize that I should be using my new Firefox as default browser but old habits die hard.

YMMV

Yet they claim (or imply) that this was robotic/cnc welding. Does this mean that the laser was cnc, but a human was sitting there with a filler rod? (How thick a filler rod, btw, with .022 wall, on 1/8 tubing?)

Could they have mig'd this 1/8 tubing job, instead of tig?

Not for 1/8 .022 wall tubing, I don't. goodgawd....

fwiw, I do have a Miller Econotig, which does serviceable tig, up to mebbe

It's also a stick machine, AC/DC/reverse. Not true-true high frequency, kinda finagles an arc-start of sorts, which a 'spert told me is OK for home-moaners, but not like a miller synchrowave et al.

The quoted site says they have "wire feed laser welding". I was thinking Tig welding but it really doesn't make that much difference (OK, the laser power supply is MUCH more expensive than the Tig supply!)

The key thing for the Mig process is that the welding current (and heat) is generated by passing current through the wire. This means that the filler deposit rate and the heat are not independent. Tig (or laser) lets you separate those variables, gives you more control. In the robot world, the difference between Mig and wire feed Tig is just one more variable (wire feed speed) and an extra servo motor for the wire feed.

The 1/8" tube is small enough that it would take a high accuracy robot arm to get at all the joints with both accuracy and direction. It would need a several hundred watt laser although you could substitute a Tig setup for slightly larger pieces (much lower operating costs). The wire feed would look pretty much like a standard Mig feed, probably spoolgun style, running some .010" wire. Key thing here is that the laser and the wire feed are separately controllable.

The Fanuc robots we used were repeatable to about .005" >> Maybe, maybe not. The price I quoted was for a Mig weld on reasonable

It's not just about the amperage, Cliff. It's how you deliver it.

KG