CNC PLASMA BUILD

[agsweeney1972]

Still a work in progress but I have chosen the Acorn for my CNC Plasma build.

Clearpath Servo's - The 2 on gantry are wired to same output rather than pairing them as I plan to use the 4th axis for a rotary chuck.
Hypertherm XP105 Plasma

Max Rapids speeds are set at 2800IPM (X&Y) and 750IPM (Z) (X can do 3000 and Y can do 3800)

Here are a few videos of it cutting random things:

[DICKEYBIRD]

Wowser, I missed this post 'til now - that thing is awesome!! Thanks for posting.

[martyscncgarage]

Are you using a Torch Height controller and if so which one?
Where did the machine torch come from?
I'd like to build a small plasma table but would like to replace the hand torch, its a Cutmaster 38

[agsweeney1972]

Marty,

I am not using a torch height controller at this point. I am waiting on the Centroid team to get a few things done in that regard, but thus far I haven't needed one anyway. I have a "Plan B" for THC that I have been planning out but so far not had the time to work on it.

The torch is a standard Hypertherm machine torch that I took the long extension off of per the instructions in the manual.

[C6MFG]

Great machine and love the pocketing on the gantry. Just started a CNC plasma build myself. Was originally going to use some left over Linuxcnc parts I had kicking around from when I decided on going with acorns on my machines. I was concerned with the THC but if you are getting good results without it....may have to re-purpose/share an acorn system I don't use much.

Jason

[agsweeney1972]

Great machine and love the pocketing on the gantry. Just started a CNC plasma build myself. Was originally going to use some left over Linuxcnc parts I had kicking around from when I decided on going with acorns on my machines. I was concerned with the THC but if you are getting good results without it....may have to re-purpose/share an acorn system I don't use much.

Jason

Thanks!

The pocketing on the gantry (and gantry side plates) saved me roughly 50 lbs on the gantry weight. The gantry is 4x6 x 1/2" wall 6061 and the pockets are 7/16 deep on the front and back and 3/8 deep on the top and bottom of the 4x6. I used simulation software to figure out the pocket design that would still provide enough rigidity and the result is that 350lbs of force on the center of the gantry beam causes a deflection of 0.021 of an inch. It weighs about 2 pounds more than a 4x6x1/4 would have and is over 3 times as stiff. considering the high rapid speeds and the fact that it can accelerate at nearly 3G's gantry weight and rigidity was a big concern (as are the anchor bolts holding it to the floor...yes it can move the 1462lb machine).

There are some plans in the works for getting a THC on this machine - just going to take me some time. The biggest factor I have found is running the machine at (or above) book speeds to reduce the heat that goes into the part. I wouldn't let the current lack of THC scare anyone away from Acorn.

[ghack]

I'd like to see more of this build.

[Reedfirst]

Pretty cool machine!

Now I want one...

[jeanmetalman1]

I really enjoyed your video's of your machine in motion. If you don't have THC on your machine, how do you program the correct arc distance, and how dod you set up the Z axis parameters? Are you using a floating head on the Z? Please let me know. I'm at the beginning stages of rebuilding my plasma table, where I am installing all new motion control hardware & software, and my stumbling point is with a reliable way to maintaining arc length, between the torch and workpiece. Thanks for your help.

J.

[agsweeney1972]

I really enjoyed your video's of your machine in motion. If you don't have THC on your machine, how do you program the correct arc distance, and how dod you set up the Z axis parameters? Are you using a floating head on the Z? Please let me know. I'm at the beginning stages of rebuilding my plasma table, where I am installing all new motion control hardware & software, and my stumbling point is with a reliable way to maintaining arc length, between the torch and workpiece. Thanks for your help.

J.

I touch off and use "tool 1" and program the pierce delay, pierce height and cut height directly from the hyperthem charts.

I am not using a floating head. I am waiting for the guys at centroid to finish up a few things so that I can use the THC but it has not stopped me from cutting these past 7 months. The machine is used in a production fab shop and very rarely does it cut anything thinner than 1/8" so warpage hasn't been much of a concern.

I have been wanted to add ohmic touchoff but have not gotten around to it. Hopefully the THC and plasma specific stuff will be working in 4.16.

Code: Select all

(Dwell Time = 0.4 Seconds)
(Retract Height = 1)
(Pierce Height = 0.09)
(Cut Height = 0.06)
(Plunge Rate = 30 IPM)

G49 H0 M25/Z
G90
G20
M6 T1
G43 H1
G0 X16.3991 Y6.6129
G0 Z0.09
M3
G4 P0.4
G1 Z0.06 F30
G1 X16.3284 Y6.6836 F180
X16.2455 
Y6.003
X18.4052
G2 X18.4636 Y6.0706 I0.1722 J-0.0899
X18.5767 Y6.1352 I0.3209 J-0.4303
X18.8524 Y6.1969 I0.2829 J-0.6175
G1 X18.8526
G2 X19.1243 Y6.1352 I-0.0139 J-0.6902
X19.2422 Y6.0707 I-0.2305 J-0.5613
X19.3073 Y6.003 I-0.129 J-0.1891
G1 X21.5622
Y6.6836
X20.5906
X20.5902
. . .