1/2"Steel with PM45

[tnbndr]

A friend stopped by today looking to have a pattern cut out of 1/2" steel. I told him I have never cut that thick before and no guarantees.
I traced the pattern in ACAD and saved in DXF, 5 minutes.
Put Cut parameters from manual into Sheet Cam but lowered speed by 25%. Guessed at start point for an edge start.
Any tips on how to locate and start torch for an edge start welcome.

Anyway I was impressed with the results. Heavy bottom dross but it knocked right off and the pics show the resulting edge and angularity.

[SeanP]

Looking good!
It's getting consistent edge squareness I seem to struggle with, even new consumables sometimes I get bad angles.

Regards edge start I had some 15mm to cut the other week, same here I hadn't cut that before and agreed to give it a try, it was some rusty stuff cut with a gas axe so a rough edge, 1st job was cut a straight edge.
That was a blessing in disguise as that was a perfect edge to start on set to zero.
I then thought if I start the next part having the lead in start on the previous cut line, again that worked great with no marking on the previous part even when left in, again that's using sheetcam to line up the edge start.

I changed the tool setting to have pierce height same as cut height and .2sec pierce delay, maybe that wasn't needed??

It cut well enough really and easy enough on consumables,,no blocked shield from bad pierce!

I have pierced 1/2'' a few times but would use edge in future if I can get away with it.

Leadin started from previous cut - 15mm parts

15mm

[urbnsr]

Nice results! Ever try using SheetCam's Wiggle leadin? It can spray the sparks, but it can also keep the torch tip clean.

Paul

[Largemouthlou]

Very nice cuts for sure!! Any reason you didn't tab all the parts together and do one continues cut? Or even group 4 together so only edge starting one time for 4 units?

[SeanP]

Nice results! Ever try using SheetCam's Wiggle leadin? It can spray the sparks, but it can also keep the torch tip clean.

Paul

I briefly tried it and can see it will help on the thick stuff, I'm not sure if I didn't have problems with it messing up the cut rule or something though, will have to look at that again, thanks for the reminder

[SeanP]

Very nice cuts for sure!! Any reason you didn't tab all the parts together and do one continues cut? Or even group 4 together so only edge starting one time for 4 units?

I'll look into that,,,,,still learning,,,,thanks for the tip

[jimcolt]

If your machine has a good working torch height control you can pierce 1/2" with a Powermax45 all day. Use about a .2" pierce height and about 1.5 second pierce delay time, no need for any "wiggle" pierce.

Cut edge angularity.....if it varies wildly around the perimeter, that means you have a damaged shield or nozzle orifice (usually the nozzle)......which is almost always caused by piercing too close or with not enough pierce delay time. If the cut angularity is excessive, but fairly consistent around the perimeter, then you are cutting too high off the material. Hypertherm shielded consumable need to pierce high and with no movement until the pierce is through the material (x , y or z), then immediately index down to the recommended.060" cut height, and accurately maintain that height through the cut.

One last thing: If your height control is good, use the cut speeds listed in the cut charts in the Powermax45 operators manual. Every day on posts I see where someone is guessing at cut speeds, or slowing it down by 25%. The cut charts in all of Hypertherm manuals were developed by running exhaustive tests burning tons of steel, aluminum and stainless in our cut labs. The specs, which include pierce height, pierce delay, cut height, cut speed (optimal or best cut and max speed) are correct, and will provide the best combination of edge angle and minimal dross. Cut slower, get more dross!

Best regards, Jim Colt Hypertherm

[tnbndr]

can pierce 1/2" with a Powermax45 all day. Use about a .2" pierce height and about 1.5 second pierce delay time, no need for any "wiggle" pierce.

Thanks for that info Jim, as the manual states edge start I did not know where to start guessing for a pierce. Next time I will try spec speeds also.
The cut was consistant all the way around.


Sean:
Those are some nice cuts

[Biker]

Sean,

Your cuts looks great.

[SeanP]

Thanks Jim, I need a extra 1/2 second adding to my 1/2'' pierce delay setting in that case!
Ummm guess I really should get a new shield as well it's the original one - 2yr old now

If your machine has a good working torch height control you can pierce 1/2" with a Powermax45 all day. Use about a .2" pierce height and about 1.5 second pierce delay time, no need for any "wiggle" pierce.

Cut edge angularity.....if it varies wildly around the perimeter, that means you have a damaged shield or nozzle orifice (usually the nozzle)......which is almost always caused by piercing too close or with not enough pierce delay time. If the cut angularity is excessive, but fairly consistent around the perimeter, then you are cutting too high off the material. Hypertherm shielded consumable need to pierce high and with no movement until the pierce is through the material (x , y or z), then immediately index down to the recommended.060" cut height, and accurately maintain that height through the cut.

One last thing: If your height control is good, use the cut speeds listed in the cut charts in the Powermax45 operators manual. Every day on posts I see where someone is guessing at cut speeds, or slowing it down by 25%. The cut charts in all of Hypertherm manuals were developed by running exhaustive tests burning tons of steel, aluminum and stainless in our cut labs. The specs, which include pierce height, pierce delay, cut height, cut speed (optimal or best cut and max speed) are correct, and will provide the best combination of edge angle and minimal dross. Cut slower, get more dross!

Best regards, Jim Colt Hypertherm

[urbnsr]

I honestly didn't know the PM45's piercing capabilities. I was merely suggesting an alternative to edge starting.

[tnbndr]

honestly didn't know the PM45's piercing capabilities. I was merely suggesting an alternative to edge starting

Appreciate the suggestion, I had thought of using it but wanted to try edge starting.

[urbnsr]

Yep - You're welcome. I use edge start when I have a one-off part, but would consider the wiggle for multiple parts. The wiggle does make a "splash", but I think it's there to help with consumable life.

PK

[Brand X]

You guys should see how nice a Hypertherm 85 cuts 0.500 MS at 65 amps. (Friends setup) Also my Esab at 70 amps.. . The cut show no bevel to speak off, and edges are crisp at the bottom. Same as the top..Book speeds for both.. 30 ipm, and 32 for the Esab.. 70 amps on a victor/Thermal Dynamics. turns out nice too, but cut speeds are slower.. I will get pics of friends Hypertherm on the thousands of brackets he cuts out.. Nice thing is the perfect low piece times with a standard style pierce. Never foul a nozzle either.. This is the Esab below.. I will get more pics of my friends work with his Hypertherm. I would upgrade to a 65 (MIN) if you plan of cutting very much 0.500. at all.

[SeanP]

I just wish my electrics were up to it!

You guys should see how nice a Hypertherm 85 cuts 0.500 MS at 65 amps. (Friends setup) Also my Esab at 70 amps.. . The cut show no bevel to speak off, and edges are crisp at the bottom. Same as the top..Book speeds for both.. 30 ipm, and 32 for the Esab.. 70 amps on a victor/Thermal Dynamics. turns out nice too, but cut speeds are slower.. I will get pics of friends Hypertherm on the thousands of brackets he cuts out.. Nice thing is the perfect low piece times with a standard style pierce. Never foul a nozzle either.. This is the Esab below.. I will get more pics of my friends work with his Hypertherm. I would upgrade to a 65 (MIN) if you plan of cutting very much 0.500. at all.

[Brand X]

I would bet there would be little difference in amp draw between a long arc 45 amp, and a standard 65-70 amp machine cutting 0.500
Reason I say this, I am using a Victor 120 amp on a 100 amp single phase 240 volt line, along with A Esab 90 amp machine.. Gives you good insight on what will work or not..(At least here) I have no real idea how your electrical is setup over there, but it sure does seem limited when stuck on single phase power..

[SeanP]

I would bet there would be little difference in amp draw between a long arc 45 amp, and a standard 65-70 amp machine cutting 0.500
Reason I say this, I am using a Victor 120 amp on a 100 amp single phase 240 volt line, along with A Esab 90 amp machine.. Gives you good insight on what will work or not..(At least here) I have no real idea how your electrical is setup over there, but it sure does seem limited when stuck on single phase power..

Not great over here, 60a is the max supply for domestic and I'm sharing with the house

[GuyMussori]

One last thing: If your height control is good, use the cut speeds listed in the cut charts in the Powermax45 operators manual. Every day on posts I see where someone is guessing at cut speeds, or slowing it down by 25%. The cut charts in all of Hypertherm manuals were developed by running exhaustive tests burning tons of steel, aluminum and stainless in our cut labs. The specs, which include pierce height, pierce delay, cut height, cut speed (optimal or best cut and max speed) are correct, and will provide the best combination of edge angle and minimal dross. Cut slower, get more dross!

It's funny what you said about Hypertherms exhaustive tests for the cut chart. Albert from Eagle Plasma tells me NOT to go by those cut charts. He said to throw them away. Maybe that's why I can't cut anything out with this useless machine. His answer to every problem I have with his machine is that I need more training. Nothing is ever wrong with his machine.

I just thought I'd share what I was told about the Hypertherm cut charts.

[weldor2005]

One last thing: If your height control is good, use the cut speeds listed in the cut charts in the Powermax45 operators manual. Every day on posts I see where someone is guessing at cut speeds, or slowing it down by 25%. The cut charts in all of Hypertherm manuals were developed by running exhaustive tests burning tons of steel, aluminum and stainless in our cut labs. The specs, which include pierce height, pierce delay, cut height, cut speed (optimal or best cut and max speed) are correct, and will provide the best combination of edge angle and minimal dross. Cut slower, get more dross!

It's funny what you said about Hypertherms exhaustive tests for the cut chart. Albert from Eagle Plasma tells me NOT to go by those cut charts. He said to throw them away. Maybe that's why I can't cut anything out with this useless machine. His answer to every problem I have with his machine is that I need more training. Nothing is ever wrong with his machine.

I just thought I'd share what I was told about the Hypertherm cut charts.

I've never had a problem following the cut charts from hypertherm. And having gone through schooling that teaches how to optimize welding and cutting parameters, hypertherm has went through a lot to provide this to us.

[acourtjester]

Guy are you using a Proma THC????? from Eagle

[GuyMussori]

Yes. That's the THC that's on my machine. I haven't used it in months because it doesn't work right and I can't get answers from Eagle Plasma so I just shut it down.

[jimcolt]

I stand behind the specs in the Hypertherm cut charts. If you cannot achive them and get good quality...then that indicates that something is out of whack. These are the things that will make the charts not work so well:

- Pierce height (ruins nozzle on first pierce....that nozzle will never cut at book specs!)
- Pierce delay time too short. Ditto above.
- Cut speed. This is one area for experimentation. The optimal speeds in the Hypertherm manuals are at a speed that is just above low speed dross, but has a respectable edge angularity. If you want less dross, go faster. If you can live with a little easy to remove low speed dross, often you can get a slightly squarer edge. Material chemistry affects this speed.....what we test in our labs is controlled and always the same....what you can get in the field is not.

- Cut height. This is the physical cut height measured in inches or mm from the front most part of the torch to the surface of the material. Higher and your cuts will be worse, lower and your cuts will be worse.

-Arc voltage. The feedback mechanism that we use to control the physical height. If you machine has an arc voltage setting on the height control....start at the book spec, measure it and then adjust the voltage higher for a higher height, lower for a lower height. As consumables wear you will need to add voltage...perhaps as much as 15 volts to maintain the correct height. If you change speed, expect to change the voltage to maintain the above physical height. If you change air pressure....you will have to change voltage to maintain the physical height. Note that there are some height controls using ohmic contact (or feather touch) that auto calibrate the arc voltage to maintain proper physical height (Plasmacam's advanced height control does, CandCNC's feather touch does, high end industrial plasma's do) with these you only set the physical height...ignore arc voltage. Can you tell that arc voltage and cut height are very critical? They are!

- Air pressure , purity. There is inlet pressure, usually specified as a range (such as 90-135 psi). Critical. There is cut air pressure...if you have a Powermax65, 85, 105 0r 125, leave them in Auto mode. If you run in manual mode and play with different cut pressures.....expect arc voltage to change, cut speeds to change, etc. If you have other systems...set the cut pressure while flowing at the torch to the specs in the manual.

- Consumables. Use genuine parts...they cost more per piece, last dramatically longer, so cost less per foot of cut.

Jim Colt Hypertherm

[GuyMussori]

I didn't mean the Hypertherm was JUNK. I meant the Eagle Plasma CNC Machine is JUNK. It has a mind of it's own. It does what IT wants not what I want.The PM 45 is WAY better then the cheepy Northern Tool plasma cutter i started with but my CNC machine is another story.
It drags the machine torch across the metal and burns up brand new tips, sometimes the arc quits for no reason, sometimes the arc won't start but the machine just keeps going like everything is good, sometimes it cuts all the detail cuts but on the outside cuts it just gouges the steel instead of cutting through and sometimes it cuts all the detail cuts and when it makes the outside cuts instead of cutting around the design it cuts right through the design. I can't get answers from Eagle Plasma except for I need more training so I shut it down.
I just wish I would have found this web page BEFORE I bought this JUNK machine because there is a LOT of KNOWLEDGE and EXPERIENCE on these pages and I think I would have made a better choice on buying a BETTER machine instead of buying one from the only CNC people I talked to.

[acourtjester]

Don't beat yourself up too much we all make mistakes now the thing is figuring out how to correct thing. Maybe with help and looking at one problem at a time we could help you. Remember you will be the eyes and the hands there so how you explain problems is how we understand them it may take time. Some times running G-code with out cutting helps to see what is going on with out wasting metal. A simple G-code can be generated using just the Mach 3 post processor to keep the THC out and using a pen to move on paper. I have used this post processor to draw or cut vinyl or for routing when I just need the tables movements.
Where are you located??

[jimcolt]

In reality.....with these low cost cnc plasma machines (any cnc plasma that uses a PC or Laptop as the control) there is a learning curve that requires some time and attention. My Plasmacam machine occasionally drags the torch on the metal, stops when I don't think it should, and occasionally produces ugly cuts. Every single time one of these things occur....I go back and check the plasma (settings from the manual, consumables and their condition), then I check the setups in the Plasmacam software......and 100% of the time I find that I have set something wrong. Could be as simple as putting a decimal point in the wrong location. These machines are not junk....they only will do what you set them up to do.

Your Eagle plasma will cut good parts. You will simply need to ensure that you understand all of the settings....and ensure they are all correct, every time you cut.

There are a few things that will cause an arc voltage based height control to drag the torch...here they are:

- Arc voltage set too low.
- Change of cut speed to a lower speed (without adjusting the arc voltage to a higher setting).
- Incorrect consumables in the torch.
-Moisture in the air.
-Worn consumables.
- Incorrect AVC (arc voltage control) delay setting.
-Incorrect corner lockout setting.
- Change in inlet air pressure.
-

There are more. An one of these will cause the torch to run too low....dive into the plate...drag on the plate. The more you run the machine and pay attention to the parameters, the better it will work.

You can buy a $100k industrial plasma machine that auto sets all of the parameters. The operator still has to be sure the correct consumables are in the torch and the correct material is on the table....other than that he simply loads material, pushes the green start butoon, unloads scrap and parts....then repeats. All cutting parameters for gas flow, amperage height control, cornering, small features, etc are automated.

With the entry level machine we have the ability to cut very nice parts and increase our shop productivity.....but keep in mind that the machine cannot do your job for you. Many of us are here to help.

Jim Colt Hypertherm