Cut Height vs Cut Speed on the Langmuir Crossfire Plasma Table

[@Sbregher]

Extremely helpful video! Thanks much!

[@CustomCreations3]

Thx…glad it was useful

[@jonbozzy9600]

Thanks again for making awesome video!!! I had my table for months and your videos help me so much.

[@DougsMessyGarage]

Shows the accuracy of the discussions about cut speed on the forums. Great experiment.

[@CustomCreations3]

Sure helped me hone in on best speed to minimize dross!

[@rodneycassidy6037]

Excellent video with lots of great info thanks.

[@LonTierney]

Really appreciate your videos. Super valuable. Completely unexpected results…

[@CustomCreations3]

Thx for the kind comment. I really need to get some new videos made!!

[@hacklabdesign]

Another great video, you’re a fantastic teacher

[@OtisMamed]

Thanks again for all you time put into this research. I wonder what amp your plasma cutter was set at for the test, as well as your air pressure. I’m going to guess that the amp was set the same for all cuts, and that *maybe* the air was controlled by your machine. I don’t have a Hyper-Therm so want to compare parameters. Price delay and pierce height would be good to note as well. Again, your time spent is very much appreciated!

[@CustomCreations3]

Hey Otis…thx for the kind words! I had the 45amp Hypertherm set to max as recommended by the manual and didnt change from that setting. Air pressure to the Hypertherm is 110psi and I let the machine control the pressure to the nozzle for cutting. Pierce delay was 0.7s ( cut charts say .4 sec and I add .3 sec because of the inherently delay in Langmuir FireControl. Pierce height was 0.15”

[@davidlemay6402]

Thank you for your videos I have the same table only for 1 month. How did you make the program for all the different speeds? That would be a great new video.

[@CustomCreations3]

Thx David. After creating the cut paths and choosing default values for 11 gage I edited the g-code to changed the speed in the file. Are you familiar with modifying g-code?

[@davidlemay6402]

@@CustomCreations3 i see. You changed the speeds after every cut in the code. I have never tried to mess with the code but I think I should get to know it better

[@CustomCreations3]

Yep. The cut path didn’t change only the speed. The g-code for our plasma tables is pretty simple, only a handful of commands so pretty easy to decipher

[@miguelpadron7807]

do you have a copy of the file your willing to sell just getting started don't know much thanks

[@CustomCreations3]

You mean the slides I used in the video?

[@miguelpadron7807]

yes

[@CustomCreations3]

@@miguelpadron7807 I had to go back and relook at the video cause I couldn't recall if there were some documentation such as powerpoint slides or not. After looking at it I dont see any slides so im not clear on what you are looking for. Im happy to give you anything that will help just needing a little more info. Is it the g-code file that cut the lines at different speeds?

[@rivermedic131]

Appreciate the effort you've put into this. My question would be, between the best cuts you got, what does the cut bevel look like? Any appreciable difference?

[@CustomCreations3]

Great Question because before starting the cut height vs cut speed research I had been cutting some tool holders in 11 gauge and they had bevel edges that forced me to tweak the dimensions to account for the bevel. Now that I have done the video I should look more closely to see if the cut height had an affect on the bevel. Ill try and do that and might do a follow on video with the results. My Hypertherm manual has a good diagram showing how torch height can affect the bevel due to the shape of the plasma "flame" my bevels were all "wider at the top and narrower at the bottom" which using the diagram would suggest I'm cutting to high. I see another video needed where I look at the bevel issue and try and understand how the height, speed, and nozzle type (regular of fine cut) are related. If you have any insight I love to hear it

[@rivermedic131]

@@CustomCreations3 thanks again for taking the time to reply. Reason I asked is because I liked the result at .06 Torch height. Looked clean. And was thinking the .08 might result in a bevel.

[@boneyardbargains]

A another great video. I have the same setup as you. I also cut a lot of 11 Gauge . material. I to have noticed the bevel mine is on the bottom side. Going to try making the cut height closer. I have also found my parts are all cutting a 1/16 smaller that they should be and my holes are are a 1/16 larger. Have you ever had this issue? I use fusion and a Hyperthem 45xp.

[@CustomCreations3]

Yes, I have found the dimensions post cut are not what was drawn up in Fusion. When doing the cam in fusion I have wondered how the compensation selection (right, center, left) was affecting the final dimensions but have not yet dug into it. I cut some 1/4” parts that had a square 1/2” hole that a 1/2” ratchet drive fit. I had to make a number of tweaks to the dimensions in Fusion so that it fit cause setting it for 1/2” it was too small. You’ve given me some good ideas for another video and it would help me to get a better understanding in the process. By the way I showed in my IHS video that Langmuir adds 0.020” to whatever we input as the “Springback” value when posting the cam. I found out you can put a negative number in this selection which allowed me to get accurate starting cut heights. Did this on some 16 gauge today and dross was almost nil! I new from measuring that my backlash as 0.013” so I input -0.007 as the springback value so when Langmuir added the .020” it came out as 0.013” which was the backlash. Thus when the torch moved to 0.060 for cut it was truly at 0.060. I just had to make sure there was minimal spingback in the plate at the start.

[@boneyardbargains]

@@CustomCreations3 A negative spring back that is a good idea. I'm going to try Hypertherms pro nest tomorrow to see if its post processor is any different.

[@CustomCreations3]

@@boneyardbargains I’d be interested in what you find…keep me posted

[@boneyardbargains]

@@CustomCreations3 What do you have your nozzle clearance diameter set to?

[@CustomCreations3]

@@boneyardbargains I have it set to 1". I was my understanding that this became the torch tip height during rapids to help alleviate the torch hitting tip-ups...cant recall where I heard that but it has been my assumption. How about you?