78psi and bevel on 10mm

[Paul14]

Hi from Australia Jim, i have home made table with candcnc electronics and powermax 85with machine torch.
I have 110 psi at machine after filtration and am getting a bevel of 1mm thru 10 mm mild steel. pm 85 displaying 78 psi wich seems to be the limit as i can adjust down but not up over this number.
*torch confirmed perpendicular to work
*new shield,nozzle 65 amp at 131volts and electrode
*swirl ring near new and looks perfect
*pierce at 3.8mm cutting at 1.5 mm.toms dthc working perfectly
*earth clamp on material
The actual cut is perfect Jim with no dross at all. hot knife thru butter, except for this bevel i could nt be happier.
Any suggestions much appreciated.
Thanks Paul
ps looking at material from edge bevel looks like this / /

[Paul14]

Jim i forgot to mention the parts that i am cutting are diamond shaped exhaust
ports. these are cut counter clock wise starting at the botom of diamond shape moving to right no bevel then bevel from right to top then no bevel from top to left then bevel again for cut to bottom finish.In other words 2 sides of diamond are perfect ie 1st and 3rd and 2nd and 4th bevelled.
Hope this makes sense.
I will re nest these parts in sheet cam so the cuts are vertical and horizontal [almost] to see what outcome is.
Paul

[Paul14]

Call an ambulance ,took z axis up to max height , slide machine torch thru to get full square edge to triple check perpendicular.decided to run torch like this changed to scriber post process which cut outer before inner[yes i know i should have checked] . this plunged torch through slates into water and before i could hit e stop y axis moves snapping machine torch in half !
nema 23 s thru 5 to 1 reduction bloody scary.
Any way after the laughter subsided it was decided to call it a day.
Friday 5:35 beer oclock ! Cheers

[Benderart]

Paul,
Sounds like you need one of my new mini-universal Snap 'n Cut magnetic breakaway mounts.

Home Page

Would have saved your torch.

[Beefy]

Hi Paul,

I'm about a 90 km from you as the crow flies. I've also built my table with Candcnc electronics and have a Powermax 1250 that I retrofitted with the Duramax machine torch which is what you will have on your Powermax 85 system.

You are having the same issue as me with this bevel. Lots of people rave about this torch and I've seen some cuts on 1" thick steel that were fantastic, but then there's the likes of us that have something out of whack. One of the best cuts I seen were done with the PM85 and this machine had 135 psi at the air inlet. He also seemed to have a good filtration and air drying setup.

I'm in the process of boosting my air supply. I've increased my compressor speed, ran 3/4" hose and fittings from compressor, through the tank and up to my filters, etc. Got to ensure my filtration is up to scratch too. Then I will see if this bevel problem has gone. If not I'll then put all brand new parts in my torch and if it the bevel still exists I guess it's time for Hypertherm themselves to check my torch out.

I'll have to remember to keep you posted when I get the above done and test the torch out again. Likewise if you find a solution to yours beforehand could you PM me to tell me what your solution was.

Cheers,

Keith.

PS You seemed to handle the breakage of your torch a lot better than I would have, ha ha. Or did you drink 3 times as much grog after that ?

[jimcolt]

Keith,

Any chance of posting some pics of the bevel you are getting with your 85....also post what specs (consumables, amperage, speeds, height, etc) that you used to get the particular cut? I will be happy to help you sort it out.

I get virtually bevel free cuts with my Powermax85 throughout its range....and the consumable life is great. My input (measured at the rear panel) air pressure when the torch air is flowing is between 85 and 115 psi.

If you see a differerence in cut quality with higher air pressure (135 psi) applied to the rear inlet....then I would guess that the higher pressure is compensating for an internal leak or restriction. The 85 has an automatic air regulator, and assuming you have it set in auto mode the pressure is always supposed to be correct at the torch...regardless of the rear panel inlet pressure, as long as the inlet pressure is within the suggested range of 90 to 135 psi, flowing)

Here is a sample I cut the other day with my 85....using the 45 amp shielded consumables. The consumables have over 1000 starts on them....and this is a sample that I cut (and compare to the lighter colored one that is cut with new consumables) to determine the condition of the consumables in my torch. The sample has 1/4", 5/16", 3/8" and 1/2" (6 7.5, 9.5 and 12.5 mm) holes....that bolts of the same size will drop through. After too much wear the holes will get out of round or incorrectly sized. As you can see....even after over 1000 starts the 45 amp parts are still cutting well.

Jim

Hi Paul,

I'm about a 90 km from you as the crow flies. I've also built my table with Candcnc electronics and have a Powermax 1250 that I retrofitted with the Duramax machine torch which is what you will have on your Powermax 85 system.

You are having the same issue as me with this bevel. Lots of people rave about this torch and I've seen some cuts on 1" thick steel that were fantastic, but then there's the likes of us that have something out of whack. One of the best cuts I seen were done with the PM85 and this machine had 135 psi at the air inlet. He also seemed to have a good filtration and air drying setup.

I'm in the process of boosting my air supply. I've increased my compressor speed, ran 3/4" hose and fittings from compressor, through the tank and up to my filters, etc. Got to ensure my filtration is up to scratch too. Then I will see if this bevel problem has gone. If not I'll then put all brand new parts in my torch and if it the bevel still exists I guess it's time for Hypertherm themselves to check my torch out.

I'll have to remember to keep you posted when I get the above done and test the torch out again. Likewise if you find a solution to yours beforehand could you PM me to tell me what your solution was.

Cheers,

Keith.

PS You seemed to handle the breakage of your torch a lot better than I would have, ha ha. Or did you drink 3 times as much grog after that ?

[Beefy]

Hi Jim,

I don't have the cut metal in question any more, been made into a grab for my little excavator, so I'll have to described as best I can, at least until the next cut.

First of all your lag lines looked better than mine. Mine seem to have more of an S shape to them. On a 90 degree turn the lag transfers and the bevel as the corner is turned is quite bad and might take an inch to straighten up.

If connected with this overall bevel problem, when a lead out crosses over the lead in (mainly on thicker plate), a tab is left just before the crossing point of the lead in, like the top of the "flame" has already reached the other side of the lead in but the bottom of the flame is still before the lead in and so the flame jumps over the gap. Does that sound like a floppy / lazy flame to you.

The bevel / lean is always in one direction as though the torch was tilted and not perpendicular to the table. Here's the funny thing though. There was a time when I changed out to a smaller nozzle for thinner plate and the lean went in the other direction.

I pretty much used the stock Hypertherm settings. My machine is a 1250 so I used the 80 amp cut charts for the Duramax torch. Torch height control with Candcnc electronics working good.

Before using the Duramax torch I was using the 1250 hand torch and I had this bevel issue then. This was actually the reason I went and bought the Duramax machine torch. Now I'm getting exactly the same problem. It's just like what Paul14 has (take a square and you can get // on one set of parallel sides and ll on the other two sides).

My air pressure may have been a bit low. With the air flowing the pressure would drop to between 80 & 85 psi at the back of the 1250. That's what I'm in the process of eliminating now so I can rule this one out.

I opened up my paper filter and it was bone dry.

It has crossed my mind about the potential for an air restriction within the 1250 itself. I've considered measuring air flow (not just pressure) if this problem persists. The Duramax specs give STANDARD LPM. Now I beleive this is flow at atmospheric pressure so would a way of measuring this be to take a large hose which would seal around the torch head without blocking any holes, and take the other end of this hose to an air flow meter. This way I should be measuring air flow at atmosphric pressure.

While I've got you Jim could I ask you about the necessity of an activated carbon filter for oil vapour. Hardly anyone mentions oil vapour yet the book says it's one of the things that need getting rid of. Apparently oil vapour will pass through all the other types of filter.

Once my systems up and running with higher pressure I'll let you know the results and take photos if the bevel problem is still there.

Cheers,

Keith.

[jimcolt]

I have seen many locations where cut quality problems were resolved by removing air line filters......each filter limits flow....even when new. More filters equals less flow.

The oil filters are necessary only if you are using an air compressor that pumps a little oil into the air.....some screw type compressors do this, and a orn out piston compressor can do this as well. Generally oil is not a problem.


Jim Colt

Hi Jim,

I don't have the cut metal in question any more, been made into a grab for my little excavator, so I'll have to described as best I can, at least until the next cut.

First of all your lag lines looked better than mine. Mine seem to have more of an S shape to them. On a 90 degree turn the lag transfers and the bevel as the corner is turned is quite bad and might take an inch to straighten up.

If connected with this overall bevel problem, when a lead out crosses over the lead in (mainly on thicker plate), a tab is left just before the crossing point of the lead in, like the top of the "flame" has already reached the other side of the lead in but the bottom of the flame is still before the lead in and so the flame jumps over the gap. Does that sound like a floppy / lazy flame to you.

The bevel / lean is always in one direction as though the torch was tilted and not perpendicular to the table. Here's the funny thing though. There was a time when I changed out to a smaller nozzle for thinner plate and the lean went in the other direction.

I pretty much used the stock Hypertherm settings. My machine is a 1250 so I used the 80 amp cut charts for the Duramax torch. Torch height control with Candcnc electronics working good.

Before using the Duramax torch I was using the 1250 hand torch and I had this bevel issue then. This was actually the reason I went and bought the Duramax machine torch. Now I'm getting exactly the same problem. It's just like what Paul14 has (take a square and you can get // on one set of parallel sides and ll on the other two sides).

My air pressure may have been a bit low. With the air flowing the pressure would drop to between 80 & 85 psi at the back of the 1250. That's what I'm in the process of eliminating now so I can rule this one out.

I opened up my paper filter and it was bone dry.

It has crossed my mind about the potential for an air restriction within the 1250 itself. I've considered measuring air flow (not just pressure) if this problem persists. The Duramax specs give STANDARD LPM. Now I beleive this is flow at atmospheric pressure so would a way of measuring this be to take a large hose which would seal around the torch head without blocking any holes, and take the other end of this hose to an air flow meter. This way I should be measuring air flow at atmosphric pressure.

While I've got you Jim could I ask you about the necessity of an activated carbon filter for oil vapour. Hardly anyone mentions oil vapour yet the book says it's one of the things that need getting rid of. Apparently oil vapour will pass through all the other types of filter.

Once my systems up and running with higher pressure I'll let you know the results and take photos if the bevel problem is still there.

Cheers,

Keith.

[Paul14]

Hi Keith , trust your having a bit more luck with your bevel issues since our phone conversation.

Jim Colt, I am absolutely blown away by your cut quality. Seeing what you can achieve with consumables that have performed over 1000 pierces too !

Before I bombard your with questions I am going right back to the start with my set up. All settings are exact from hypertherm book for best quality not production.
After triple checking torch/machine/cut settings I will start too investigate/adjust my speed/accelleration settings in mach as this could hold the answers.

Ps purchased 25" hand torch for the pm 85. Fantastic bit of gear .

will keep you posted on progress
Paul

[Stout]

Jim,
What cleanup was required on the part you cut to test the bolt holes? I don't see any indication of grinding. Dross free cuts?

[jimcolt]

The holes had some minimal dross...just chipped it off with a scraper by hand...took about 10 seconds. The dross in the holes is called low speed dross, the result of slowing down to 60% of the recommended cut speed to minimize taper. The exterior of the cut was done at full speed...and there was virtually no dross.

Most people cut too slow all the time with plasma. The specs that come with Hypertherm systems are correct....cut at the speed, height and power levels listed in the operators manual and dross will be minimal. Every day I respond to multiple users compalining about cut quality....9 out of ten times I convince them to use the specs out of the operators manual. Those that call me back almost always are amazed at the improvement as compared to just "dead reckoning" on cut specs!


Jim

Jim,
What cleanup was required on the part you cut to test the bolt holes? I don't see any indication of grinding. Dross free cuts?

[Stout]

I'm using a Hypertherm Edge controller and the cut charts for my 1250 and I just don't see anywhere near this quality of dross free cutting. I'm currently replacing the compressed air plumbing and have installed a refrigerated air dryer so I can remove the paper element from the path. The current installation has about 100 feet of 3/8" air hose so maybe I have a flow issue.

I'd even consider going to a PM85 with duramax torch if I have to.