cutting Thin stainless sheet Powermax 45

[adscnc]

I'm aware that cutting very thin sheet with a quality edge is difficult.
What is the the best thickness to use for name plate work in thin stainless?

[jimcolt]

You can cut SS very well with the Powermax 45.....however it is an air plasma system, and air has a 20% oxygen content that will leave a brown oxidized edge, and will leave a taper on the edge. The key to the best cut quality is to maintain the speeds and torch heights that are listed in the Hypertherm manual.....Stainless likes high speeds! The 45 can do a good job on SS from about .062" to .375".

Jim

[WSS]

Originally Posted by jimcolt You can cut SS very well with the Powermax 45.....however it is an air plasma system, and air has a 20% oxygen content that will leave a brown oxidized edge Jim

Jim,
Can we use nitrogen with our air plasmas to get rid of the oxide? It seems like I heard we could use some other gas types (certainly not oxy!) with air plaz.

Thanks,
WSS

[jimcolt]

You can use nitrogen with a Powermax system...the oxide layer will be better...but expect more dross on the cut edge.

Jim

[dada]

wouldn't be the speed stated in the manual is way too fast? I'm afraid it will splashed back...

[jimcolt]

All of the speeds stated in Hypertherm manuals are the correct speeds. The hand torch cutting speeds are maximum , while the machine torch speeds are for best quality. Hypertherm spends thousands of hours developing these cutting specifications in their labs in NH......guaranteed to work!

Jim

[bakerj99]

Mr. Jim Colt

i have to slow down from the opt. speeds. Would having a disconnect on the ground cable have anything to do with it or when hypertherm test do the use cold roll steel or a hot roll steel with a low recycled materials content? then there is the "hard spots" on the hot roll material that if i dont slow the speed down to about 20% from the opt. speed it will not cut through until the torch gets out of the hard spot area. on the other hand i could just be nuts!! here is a pic of the disconnect.

thanks
bakerj99

[jimcolt]

Your disconnect should not make any difference in cut quality....in fact the new Powermax65 and 85 have similar disconnects on the work lead. Also, "hot spots" or spots in steel with a hardness change will not affect plasma when operated at optimum speeds. The plasma arc is in the 25,000 F. temperature range, and also uses the 20% oxygen content in air to provide an exothermic reaction with steel. The optimum speeds listed in the Hypertherm manual are nowhere near the maximum speed that our systems will cut. These speeds assume the correct air pressure and flow, assume that you pierce and cut at the recommended heights, and are using the correct part number consumables. I will guarantee that any Hypertherm system will be able to achieve the optimum speeds on virtually any grade of carbon steel. The optimum speeds are listed under the machine torch cutting paramters, and should be used whether you have a machine torch or a hand torch mounted on your cnc machine. Also, use the consumable parts listed for the machine torch....even in a hand torch when machine cutting.

I typically will start at the optimum settings.....and if I have dross I will increase the speed slightly until the dross goes away. If there is little or no dross, but excess edge angularity, then I will slightly decrease the speed until dross starts to develop.

It would be my guess, based on 32 years of experience...that there is another issue with your system that may be causing your machine to not cut through the plate at the optimum speed settings. Could be moisture in the air, water usually stores up in pockets in your shop plumbing, then exits in slugs,which could explain the "hot spots" that do not cut through. You could have a flow restriction or a leak in the plasma system or the torch leads, low air flow will cause exactly the same symptoms as turning the amperage down. You could have a height control system (you did not say what your machine and height control method are) that is not maintaining the recommended height within .010"....this will cause penetration issues. You could have a height control that pierces too close to the plate....one pierce too close will cause damage to the nozzle orifice that will affect cut quality.

Hope this will help troubleshoot the issues.

Jim Colt

[bakerj99]

Mr. Colt

the machine is a hypetherm 1650 on a torchmte3 5x10 with their AVHC. i will check the filters separators and the lines. i use the unshielded consumables but the manual does not have settings for the 80 and 60 amp unshielded tips so i go by the shielded settings, is that ok? as for the torch i dont think that there is a problem there except that i should have ordered a 35' or 50' torch ( can i just order the cables and not the torch? if so would you happen to know the part #s?). the swirl ring that i have been using is the one that is for everything from 40-80amp but i have ordered the fine cut hand torch one to put into the machine torch, will this make a difference? i did not notice a fine cut machine torch swirl ring thats why im not using one.

is there any literature on the powermax 85 with speed charts? im fixing to have to get a machine that is single phase and wanted to compare it to the powermax 80.

thanks for your time on a "weekend" (make sure hypertherm pays your overtime)
bakerj99

[jimcolt]

OK.....you have clarified a lot!

Number one, the unshielded consumables are old technology....the only reason they are offered for use on Powermax systems is that they have a little better visibility for 3 dimensional cutting applications where you need to get into tight spots. They do not provide anywhere near the piercing capability, the cut quality or the life of the shielded consumables. And, the cut charts for the shielded parts will not work at all for the non shielded parts.....totally different technology and performance.

The shielded parts allow thicker piercing as the shield is electrically isolated from the nozzle, which eliminates double arcing and blowback damage to the nozzle orifice. Further, the shield air flow is designed to coaxially impinge (squeeze) the plasma arc, which increases its velocity and energy density, providing better cut edge squareness, higher cut speeds as well as longer consumable life. You should switch to the shielded parts and use the part numbers and specifications listed in the Hypertherm manual.....you will be very happy with the results. For the FineCut parts use the 220404 Deflector and the same swirl ring (120925) that is used for the shielded 40, 60 and 80 Amp parts, the separate FineCut swirl ring is for hand cutting applications only.

You can order just torch leads if you need them, they are listed in the parts section of your manual. For more detail you can download the service manual from the Hypertherm website. Hypertherm | Plasma Cutters | Plasma Cutting Equipment | Metal Cutting Equipment click on document downloads tab.

I tend to work 7 days a week...as I enjoy the aspect of helping people with their plasma cutting applications! I have been with Hypertherm over 32 years....and actually the more I work, the less I make (hourly!)

Best regards, Jim

Originally Posted by bakerj99 Mr. Colt the machine is a hypetherm 1650 on a torchmte3 5x10 with their AVHC. i will check the filters separators and the lines. i use the unshielded consumables but the manual does not have settings for the 80 and 60 amp unshielded tips so i go by the shielded settings, is that ok? as for the torch i dont think that there is a problem there except that i should have ordered a 35' or 50' torch ( can i just order the cables and not the torch? if so would you happen to know the part #s?). the swirl ring that i have been using is the one that is for everything from 40-80amp but i have ordered the fine cut hand torch one to put into the machine torch, will this make a difference? i did not notice a fine cut machine torch swirl ring thats why im not using one. is there any literature on the powermax 85 with speed charts? im fixing to have to get a machine that is single phase and wanted to compare it to the powermax 80. thanks for your time on a "weekend" (make sure hypertherm pays your overtime) bakerj99

[dada]

oh... i get some time to try on the optimum speed at my customer site... make them as my guinea pig.. lol