Hello all! I’m still a newbe-ish, trying to make some signs for friends. I’m gradually getting my head around the geometric relationship between the kerf size and the scale of the cut. I’ve got a pile of wasted sheet because the kerf burned up the steel between two lines. It appears that I need a minimum of 1/4" between lines and even then, many cut through. So, here’s my question… Could I change to a different tip to get a smaller kerf, or is there some other way to cut finer geometry? Any thoughts or suggestions would be greatly appreciated!
Maybe this will help you.
This is what I have found to work with most plasma cutter nozzles/tips that most people have in their shops or garages. NOTE: Orifice hole size 1mm = .03937"
20 amp tip - 0.6mm/.025" - 15 to 20 amps - 50 to 55 psi
30 amp tip - 0.8mm/.030" - 21 to 30 amps - 55 to 60 psi
40 amp tip - 0.9mm/.035" - 31 to 40 amps - 65 to 70 psi
50 amp tip - 1.0mm/.040" - 41 to 50 amps - 65 to 75 psi
60 amp tip - 1.1mm/.044" - 51 to 60 amps - 65 to 75 psi
70 amp tip - 1.2mm/.047" - 61 to 70 amps - 75 to 80 psi
80 amp tip - 1.3mm/.051" - 71 to 80 amps - 75 to 80 psi
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Thank you! Any suggestions on where to get tips?
You could always get them from me. Send me a email on what you are looking for.
Geoerge has a great reputation for great parts and consumables…
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George is a great resource!
Have you done any testing to determine your actual kerf width?
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Sorry for the questions but answering them might help get your answers…
What distance is your nozzle tip to metal? Reasoning for asking is further away the wider kerf
what thickness of metal? this helps with your answer for amps and speed.
What nozzle tip are you running? you might have a gouging tip
what speed and amps are you running? you might be going too slow and amps don’t need to be maxed out if cutting thin metal.
Wow! First, I want to thank you guys for your willingness to share your experience… I know it isn’t free. So, George, I will contact you. And to address Don and toolboy’s questions: Yes, As near as I can measure the kerf is .06". I use the 1/16" gauge to set my cut height. I got my consumables from Amazon… https://www.amazon.com/dp/B089SPLSHH?ref=ppx_yo2ov_dt_b_product_details&th=1#:~:text=Submit-,AWLOLWA%2045pcs%20IPT-60%20PT-60%20IPT-40%20PT40%20Plasma%20Cutting%20Torch%20Tip%20Electrode%20Shield%20Cap%20Stand%20Off,-Visit%20the%20AWLOLWA
I’m running 13 Ga. steel at 85IPS and 35 Amps. The cut is good and the slag is minimal.
So, I guess my confusion results from my lack of understanding of the relationship of the kerf size to the tip. As I see it, the thinner the stock, the lower the amperage and speed. Does that also equate to a narrower Kerf or is the kerf always the same?
Again, I appreciate your help!!
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The kerf is generally considered as the size of the orifice plus 0.01”. This will vary for numerous reasons including the age of the tip, thickness of material, machine you are using ect. Ect. If you need accuracy it’s best to do a test to verify the kerf width. Cut a 2 inch square with a 1 inch hole. Set in cam to cut the CENTER of the line. The difference between the size you cut vs the size you drew is your kerf width.
ie. if you drew a 2” square and it measured 1.945” when cut then your kerf is 0.055.
Amperage won’t change the kerf width. If you want a smaller kerf you have to use a tip with a smaller orifice…. Which requires lower amperage…
Cutting with a 60 amp tip at 30 amps won’t decrease your kerf width.
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