Laser Burning Question

[shaley]

I don't know any machinist forums to post this too so here goes.
Anybody had any experience with burning 5/8" tap drill holes in 1/2" plate steel with a NC Laser. Does the material in the heat zone micro harden so as to make tapping very impractical? I can have it burned slightly under and then run a drill through but it will drive the labor cost sky high.

 

[RobS]

How 'bout waterjet instead. It's not as precise but you have no heat affected zone.

 

[AlanB]

Might give Barrry a call here. He is a great guy, and very, very familiar with lasers etc. There are a couple laser specific forums as well, although I am not familiar with them.

Introduction

 

[schmism]

I was not aware that laser cutting was availabe for plate that thick.

In my experience it has be limited to thin gauges.

Most "patern places" (custom machine shops) use a water jet in these parts. The precision on water jet should be sufficent for a tap operation depending on required % threads.

 

[hazmat]

Why not conventional Mill or CNC mill? What are you trying to build?

Waterjet or Laser are typically for thinner metals and/or irregular shapes.

The Home Shop Machinist and The Machinist's Workshop (More tolerant of "rookie" questions

Practical Machinist - manufacturing and machinist forum - home page more a "pro" site

 

[scott_vt]

I don't know any machinist forums to post this too so here goes.
Anybody had any experience with burning 5/8" tap drill holes in 1/2" plate steel with a NC Laser. Does the material in the heat zone micro harden so as to make tapping very impractical? I can have it burned slightly under and then run a drill through but it will drive the labor cost sky high.

Afternoon shaley,
If the material is CRS plate low carbon there should be no problem laser cutting the plate. Obviously you need a machine that can handle 1/2" plate but not a problem ! There should be no hardening issues so therefore no tapping issues either !

If you are trying to do the same thing on alloy material then you potentailly can have problems !

As the others have suggested, waterjet is a viable option also, but not as accurate as laser. I have been a toolmaker the past 35 years but most all of that type work we subcontarct. Hope this helps answer you question.

 

[shaley]

Thanks Guys,
I'm trying to make some wheel adapters out of A36 PL. If I can keep the machining to just one machine operation it will keep my cost down. The Laser company I spoke with says 1" max for there machine.

 

[blacksmith]

Waterjet is the way to go. At work we have used it on 1" nickel chrome plate which is very hard to machine and it did a very good job.

 

[EdC]

Shalley
I used to do some computer work for a company that did waterjetting. They would rough cut parts to within .01 in. and then send the parts out for finish machining. When I moved they were upgrading to what they hoped would be .001 in accuracy. Would that be accurate enough?

 

[czechsonofagun]

you could also use electro erosion:

Spark erosion - Wikipedia, the free encyclopedia

in some factories they have it for removing broken taps and such. Works well, but maybe it is more common in Europe than in USA.

 

[schmism]

the more common name around hear is EDM or wire EDM

Electrical discharge machining - Wikipedia, the free encyclopedia

But its often a slow process, expensive and usually only used on otherwise non-machineable materials (such as hardened tool steel for dies)

 

[have_blue]

I don't know any machinist forums to post this too so here goes.
Anybody had any experience with burning 5/8" tap drill holes in 1/2" plate steel with a NC Laser. Does the material in the heat zone micro harden so as to make tapping very impractical? I can have it burned slightly under and then run a drill through but it will drive the labor cost sky high.

Depends on how many holes you expect from each tap. If this is going to be an ongoing production process, I don't think it would be practical. If you're going to tap a few holes and then you're done, it could work. If you keep a CO2, Argon, or nitrogen blanket on it while it's burning, you can avoid some of the abrasive scale.

 

[Renze]

I've been in the laser cutting business for awhile.

I'd say with 1/2 inch plate and 5/8 holes, which is about M14 in metric, the cut will be rough. Lasers cut rough due to the heat put into the material when cutting holes with the same diameter as the plate thickness.

Are you talking lots and lots of holes ? Then either use the laser to precisely engrave the center of the hole and then drill and tap (and save on laser time because spouting a start hole costs as much time as making a 2 feet cut) or laser a hole that is 2mm smaller than what needs to be tapped, and use a tap drill. I dont know if you can get them in that size, or in imperial sizes, but it is a tap with a drill up front. we used them all the time.

 

[sandman2234]

I am wondering if this is a couple of wheel adapter's for his tractor or is he fixing to start a manufacturing line of them?
If just a couple, heck mark them out, send them to me and I will drill and tap them. If your starting a business, I am not the one you need to talk to.
David from jax