Problem plasma cutting aluminum 1/8"

[matin]

I want to cut 1/8 aluminium with powermax 65.

I use 45 nozzle and set the current to 45.

used this setting and thc is from candcnc :

This setting is from Hypertherm manual for unshield 45 nozzle:

torch to work distance =0.06
pierce height =0.15
pierce delay =0.4
cut speed =100
gap voltage =130 volt
Thc rate =10
max z axis speed= 40 inch/min
accel = 35

My problem is variable bevel angle in perimeter of cut.

Could you please tell me What is the problem ? And how can I solve it ?

Also ,Could you please answer to these following very important questions :

1) What is best setting for nozzle selection ,speed and gap voltage and cutting current for cutting 1/8 inch aluminium ?

2) As I read , cutting with lower speed and lower current is better for improving
Bevel angle , if I change the current to 30 or 35 and keep speed same as 100 , Is it better ? My problem is , when I do
this with same speed 100 inch/min ,How must I change the gap voltage from existing 130 volt.

Could you please give me a guide or formula that for certain nozzle , if we change the cutting current, how
must I change the gap voltage for thc , and if I change the cutting speed ,(lower or higher than
Best quality setting in manual ) then how must I change the gap voltage.

This is very important for me . Is there any guide foe setting gap voltage for different curents and different speeds.


Best regards ,

[Craig]

I am new to cutting aluminum but when I was cutting 1/8" with my PM 65 at 45 amps, and had good results following the settings in the manual. If you are using unshielded consumable I assume you don't have ohmic sensing. For me ohmic sensing is the single most important feature for getting quality cuts.

Craig Johnson

[jimcolt]

For normal flat material cutting you should always use the shielded consumables in your Powermax65. They cut cleaner, cut squarer and last longer than the non shielded setup. This combination will produce the best quality on aluminum of 1/8? thickness. The non shielded consumables are sometimes used for cutting parts with 3 dimensional shapes?or when yopu need more clearance around the plasma arc. The shielded consumables use the patented conical flow technology that improves arc stiffness and energy density, as well as improving the life of the nozzle orifice.

A varying bevel is caused by one of these issues:
1. A damaged nozzle or shield orifice. Inspected under a 10x magnifier?the orifice of the nozzle need to be perfectly round with no craters and no nicks. A beveled or cratered edge is caused by normal wear, nicks or notches in the orifice are caused by piercing too close to the material. There is a section in your operators manual that describes inspecting the consumables.
2. Torch not properly squared to the metal plate.
3. Varying torch to work distance while cutting.

Cutting curent

It is always recommended that the cutting current for the shielded consumables remains at the maximum rated amperage. 45 amps is for the 45 amp consumables, 65 amps for the 65 amp consumables. This produces the stiffest arc and the highest level of energy density. When I suggest using the lowest amperage for best cut quality I mean that the 45 amp consumables will cut better than the 65 amp consumables. When using the FineCut consumables (steel and stainless only) there are a few different choices for current settings, however I suggest you follow the cut charts in the manual for best results.

Arc Voltage.

This is just a reference for controlling the torch height. The suggestions in the cut charts are perfect when used in a laboratory setting, but will vary in the field. Start with the settings in the charts and adjust voltage until the physical cut height is correct. Lower voltage = lower cut height. Cut height is critical and will affect angularity.

Jim Colt Hypertherm

[icmplasma85]

Jim,

I noticed when you mentioned FineCut you said steel and stainless only, but what's the reason you're not supposed to cut aluminum with these consumables? I've always wondered this since they're are no settings in the manual, but I have actually cut aluminum with finecut, I just had to play around with the settings until I got it. My theory was if a 45 amp shielded setup will work, so will finecut being the same amount of amps. Now granted, I don't cut anything thicker than 1/8" aluminum with the finecut consumables, but I've just always been curious as to why its not recommended. Seemed to cut great once I tweaked the numbers a little.

[jimcolt]

Our (Hypertherm) process engineers developed the FineCut parts specifically for stainless and carbon steel. They never developed cut charts for aluminum with these parts. I find that on aluminum the FineCuts build up with aluminum spatter rather quickly, and have to be cleaned off often.

I cut very thin aluminum (under about .050") with Fine cuts using the same specs I do for steel...they work well. In my opinion thye 45 amp shielded consumables (Powermax45, 65 85 and 105 as well as all Duramax torch upgrades) work better on aluminum thicker than .050". Better cut edges, about 3x longer consumable life, less dross. The only disadvantage is a slightly (about .006") wider cut kerf.

Jim Colt

Jim,

I noticed when you mentioned FineCut you said steel and stainless only, but what's the reason you're not supposed to cut aluminum with these consumables? I've always wondered this since they're are no settings in the manual, but I have actually cut aluminum with finecut, I just had to play around with the settings until I got it. My theory was if a 45 amp shielded setup will work, so will finecut being the same amount of amps. Now granted, I don't cut anything thicker than 1/8" aluminum with the finecut consumables, but I've just always been curious as to why its not recommended. Seemed to cut great once I tweaked the numbers a little.

[Largemouthlou]

I cut all my alum with fine cut consumables up to .125 and as small as .050.. They do very well for me.. Some day I will up grade my system to play with the big boys but for now all is well!!

All other alum is cut with standard 40, 60 and 80 nozzels using the cut charts

Using a 1250 and old machine torch..