Which machine to cut sheet metal/plate?

[2cool2hear]

Been working with sheet metal for a while now. I'm looking for a machine that will cut sheet metal and plate because at some point I'd like to stop relying on laser vendors to cut them for me.

I'm taking a couple classes at community college this year to learn electronics/microcontroller so I can troubleshoot, pinpoint, and fix/upgrade the parts on used/broken machines/equipments.

I've thought about buying a cnc plasma cutter, found a several within my price range ($5,000), or maybe buy a kit and assemble it myself. Has anyone used one that makes clean cuts, like consistently? I don't want to spend too much time grinding the edges smooth. If that's the case, I'll have to continue using the vendors until I can afford something better.

I would really like to own a laser or waterjet but I think they're far beyond what I can afford. Unless I missed something. Has anyone rebuilt/built one for a fraction of the cost? Other suggestions are welcome. I'm just to find ways make progress.

Many thanks

 

[zkling]

Thickness? Material type? Sheet size?

 

[dr_clyde]

You're not going to be able to compete with a laser or a waterjet on the home level.

Air plasma is the least expensive, but quality is not near that of a laser or waterjet. It does reasonably good on 1/4" or thicker.

If you're up for a challenge, you could pick up a NC punch press. It's how they did sheet cutting before lasers.

 

[tarbellb]

I dont think you can touch a water jet in price or DIY build. Laser, probably the same boat.

There is a member on here who built a 4'x8' CNC plasma table with pretty awesome results. The title is something like "No idea what Im doing, CNC build"?

 

[tarbellb]

If you want to go the manual route, I bought the Milwuakee metal circular saw. Its a beast, but kinda nasty operation- hot chips and sharp edges.

 

[kazlx]

It depends on what kind of results you need. Air plasma won't compete with a laser or water jet cutter, but the results are good and dross can be minimal with the correct setup.

Tarbell might have been referring to me. I built my own CNC plasma table. I have the link to my build thread below. Your $5K budget is a little light for a build with new parts and plasma, but you might be able to find a used table for close to your price. A lot depends on how big you need to cut. You said mostly sheet, so I would assume thickness isn't much of an issue. Something like a Hypertherm 45 will easily handle any sheet metal.

 

[altersaddle]

For just sheet, a nibbler or shear works well. I've got an air nibbler, I use it to rough out pieces of 20ga steel.

Also use the snips (aviation snips) and thin cutting wheels in the angle grinder.

Down side to the nibbler are the little crescent pieces it makes. They are sharp and will get in your clothing.

 

[RivennHewn]

http://www.garagejournal.com/forum/showthread.php?t=289273

 

[2cool2hear]

Thickness? Material type? Sheet size?

No larger than 4'x4' carbon and stainless, around 3/32" thick.

 

[Guster]

Mostly straight? Curves? Lots of custom shapes? Volumes? Changes what you demand from the tools too.

In those thicknesses a bandsaw is quite versatile for curves and custom shapes but not exactly fast and stainless is hard on the blades. In combination with the bandsaw and a handheld plasma cutter you could make wooden templates and then cut around it with plasma too.

Zip discs make quick work of straight'ish sections otherwise a worm drive skillsaw works well to cut long straights fast. Though not a tool you'll use all day long due to noise and constant bombardment of hot chips.

Plasma has the other tools beat for speed and dexterity and a CNC table takes it to the next level. Will take a little time to dial in the setup. Don't forget to factor in a good compressor to keep up with the air supply demand. Also a work shop power supply that can run the compressor and plasma at the same time. You may still need a grinder, linisher or flapdisc to touch up edges too.

 

[mike13u]

If you aren't cutting watch parts or making signs with a bunch of lettering under an inch in size, today's CNC plasma tables and power sources from reputable manufacturers all make very good cuts once dialed-in.
I have a Dynatorch 4x8' table with a Hypertherm Powermax85 and get excellent results on my machine.

 

[steel 35]

Find someone with a cnc plasma in your (area)? and have them cut one of your pieces.

 

[tarbellb]

Find someone with a cnc plasma in your (area)? and have them cut one of your pieces.

Are you even reading any of this Steel35? He has already created files, located, and cut pieces through a vendor.... geesh.

And yes I was referring to kazlx, he has a awesome and extensive write up on building your own CNC plasma.

As mentioned before, after seeing your smaller foot print (4'x4') I think a CNC plasma is your best option. More clean up but fast, accurate, and repeatable.

Plus I want to see somebody else do another CNC build :]

 

[steel 35]

If you want to go the manual route, I bought the Milwuakee metal circular saw. Its a beast, but kinda nasty operation- hot chips and sharp edges.

Are you even reading any of this Steel35? He has already created files, located, and cut pieces through a vendor.... geesh.

And yes I was referring to kazlx, he has a awesome and extensive write up on building your own CNC plasma.

As mentioned before, after seeing your smaller foot print (4'x4') I think a CNC plasma is your best option. More clean up but fast, accurate, and repeatable.

Plus I want to see somebody else do another CNC build :]

Ok let's check in here; He is asking about CNC plasma You suggested A Milwuakee metal circular saw, What the **** is that!
Ask for piturs of my machine now. Done now.

 

[zkling]

Are you even reading any of this Steel35? He has already created files, located, and cut pieces through a vendor.... geesh.

And yes I was referring to kazlx, he has a awesome and extensive write up on building your own CNC plasma.

As mentioned before, after seeing your smaller foot print (4'x4') I think a CNC plasma is your best option. More clean up but fast, accurate, and repeatable.

Plus I want to see somebody else do another CNC build :]

I think what he was suggesting was to basically try a sample piece to see what a small budget plasma system is capable of. Hence the "one of your pieces". Not a bad idea at all. Certain shapes and cuts are better suited to water jet or laser cuts which is what he is using now over plasma. Best summed up by kazlx in "It depends on what kind of results you need".

2cool2hear, work envelope wise you are well within the limits of a small plasma setup, the question now is will it produce acceptable results on your specific parts. Can you post a drawing or picture of your current parts?

 

[kazlx]

3/8" CRS right off the table. Cut specs right out of the Hypertherm manual. If you are going to do a CNC plasma table, do yourself a favor and get a Hypertherm.

 

[zkling]

What was your travel rate on that piece kazlx?

 

[kazlx]

I had 41 ipm on that piece. There was a tiny bit of dross on the bottom of the cut that could be tapped off with a small hammer, but the edges are as-cut. The corners are also looped to get them sharp. That piece was specifically cut as a test for setup before cutting good material.

 

[mike13u]

Some pics right off my table. Thinker than you are looking for, but its all I have pictures of right now.

[URL=http://s1089.photobucket.com/user/mike13u/media/Steel5.jpg.html] [/URL]

[URL=http://s1089.photobucket.com/user/mike13u/media/Steel4.jpg.html] [/URL]

[URL=http://s1089.photobucket.com/user/mike13u/media/Steel6.jpg.html] [/URL]

 

[kazlx]

Is that 1/2"? Cuts look good.

 

[mike13u]

Is that 1/2"? Cuts look good.

3/8 . Thanks.

 

[steel 35]

Nice cut's

Another great tool, Peck Pierce for centerdrill;
Two holes dross cleared with a weak fingernail, & not clear through 11g

 

[tarbellb]

My bad steel 35 I totally glossed over the laser vs plasma in your response.

 

[coma13]

http://www.garagejournal.com/forum/showthread.php?t=289273

That actually looks pretty interesting for a home shop user like myself.

 

[Andrew S]

Take a look at Turn Wright Machine Works on YouTube, he bought a PlasmaCAM table, and has improved it considerably. Lots of videos of it in action, along with the finished parts.

 

[kazlx]

That actually looks pretty interesting for a home shop user like myself.

Nothing personal against the guy, but those cuts look like ****.

 

[coma13]

Nothing personal against the guy, but those cuts look like ****.

Yeah I assumed that was more torch settings than gantry setup. I have zero experience though? I considered building one like you did I'm just not sure I want to commit the space.

 

[kazlx]

He has multiple issues going on. The cuts are beveled, which should be less of a problem with thinner material, so either his torch height is off or he has contaminated air. The biggest issue I see is the holes don't even look round. That could be multiple things. IMO, that's not a part I would let out of the scrap bins, never mind posting it as a demo pic. Everyone wants to build a cheaper table. I get that people are on a budget, but if you are going to spend money to build a table, invest in quality stuff. That way you aren't pulling your hair out all the time. The biggest wtf I always see is people spend all this time and money on getting a table and then top it off with a crappy plasma. I 'saved' money by buying a used Hypertherm and all it did was convince me that when I bought another plasma it would be a bigger and better Hypertherm.

I used what I would consider 'good' parts and have still had a learning curve. I couldn't imagine troubleshooting more stuff when your gear and hard parts are all suspect. The interface and some of the other stuff is just worth spending the money on to do it right IMO.

 

[mike13u]

He has multiple issues going on. The cuts are beveled, which should be less of a problem with thinner material, so either his torch height is off or he has contaminated air. The biggest issue I see is the holes don't even look round. That could be multiple things. IMO, that's not a part I would let out of the scrap bins, never mind posting it as a demo pic. Everyone wants to build a cheaper table. I get that people are on a budget, but if you are going to spend money to build a table, invest in quality stuff. That way you aren't pulling your hair out all the time. The biggest wtf I always see is people spend all this time and money on getting a table and then top it off with a crappy plasma. I 'saved' money by buying a used Hypertherm and all it did was convince me that when I bought another plasma it would be a bigger and better Hypertherm.

I used what I would consider 'good' parts and have still had a learning curve. I couldn't imagine troubleshooting more stuff when your gear and hard parts are all suspect. The interface and some of the other stuff is just worth spending the money on to do it right IMO.

^^^^ This