Newb question about fine cuts

[ChelanJim]

Here is some advice that might be useful:

@langmuir-daniel

To get the best angularity possible, be sure to use the lowest amperage nozzle that can still clean cut the thickness you are working with. For example, when i cut sheet metal with my 60 amp Hypertherm, i use a 30 amp nozzle for the best angularity (typically about 3 to 5 degrees).

@Simsworx

I would suggest running your RazorCut45 at 45A, as thats the settings for the nozzle. (Lower amperage may improve things, but I’ve yet to set it.) As far as speeds / feeds - We took the Hypertherm 45 chart and reduced it 66%. It provides a good starting place to adjust as needed.

@mechanic416

0.8 are 30 amp unshielded tips so you wouldn’t use them for 1/2". 1.0mm/50 amp tips and 1.1mm/60 amp tips can be shielded or unshielded. If your using 1.1mm/60 amp shielded tips with a CNC shield you need to measure the torch height between the tip and work piece not the shield and work. If the distance between the shield and work piece is more then .035" the torch height is way to high.

@langmuir-daniel

Let’s say you run two line tests. Both with THC off. On the first test you let IHS set the cut height. On the second test you manually set the cut height. If you get poor cut quality on the first test, it’s due to IHS setting the cut height too high or too low. You’ll need to compensate for this by either reducing or increasing the cut height in your g code.

IHS will set an incorrect cut height for two reasons. One is to compensate for spring back in the material. The torch and slide has weight which will cause the material to deflect (obviously worse for thin material). This has the tendency for the actual cut height to be lower than the programmed cut height. Second, there is some backlash in the z axis lead nut which must be compensated for. If it was not compensated for, it would have the tendency for the actual cut height to be lower than the programmed cut height. The backlash is the same whether you are working with sheet metal or thick plate and is built into the post processor of Sheetcam. I believe it’s .020”.

Let’s say that you program your cut height to .060”, but find that in reality your actual cut height is .080”. You need to set your cut height in Sheet CAM to .040” in order to guarantee a .060 cut height.

Make sure that you have the correct consumables for your torch purchased from either George or Bakers’ Gas or Langmuir. And verify that you have all the consumables in the stack and are in the correct orientation (I assembled my Hypertherm torch wrong once…don’t ask!).

And when in doubt, replace the nozzle. They will wear more quickly than the electrode.