Too many new variables, not a good cutting day

[mg6studios]

Well, I cut ¼" mild steel plate today for the first time on the CFP. Prior to this I have only cut 120 and 060. It was not a good day. Waste created.

I have a new cross cut jig design I wanted to prototype.

Firsts:

• Designed a complete product in Fusion
• Did post-processing for the Razorweld CUT45 CNC in Fusion.
• Cut ¼" plate at all on the Razorweld.

As you can see in the picture, the dross was horrible. So bad, even after a grinding session it may be junk. I used settings from the hypertherm manual cut chart, though I am running a RW CUT45 CNC with machine head. I just changed consumables recently. And, again in the middle of this with the same results.

I also had THC issues throughout the cut. It was acting really weird during cuts, moving up and down noticeably for no apparent reason as the sheet was fairly flat. Does mill scale cause issues?

Note, this machine has been working great up until now. I’ve cut more sheet than and I can count. I keep up with maintenance and nothing else changed. Only other thing I can think of is that I’m pretty sure I used the “cheap” amazon consumables rather than the stupid expensive ones I got from the guy here.

TIA

[mg6studios]

I tried slowing the feed rate down as much as 50%. That seemed to help the cut quality. But pierces were terrible pretty much everywhere. Some cuts it barely made it through 1/16" of the material. see pic

[mg6studios]

[mg6studios]

[toolboy]

so I gotta ask…where wa the material clamp…

Also…why would you let it cut so much knowing there was a problem after the firs few cuts…?..

So what I see is top dross…usually to fast of cut speed or higher amps required…you never really provided the amps you were trying to cut at…

also what size of tip were you running?

one reason I do not buy knock off tips from off shore copmanies…

let me ask you was the whole sheet of wasted material and time worth the savings on you paid for cheap consumables…?..?

and the other thing about your pictures…what does your consumable tips look like after all that cutting?..I would think you have a possible moisture issue

[mg6studios]

@toolboy

so I gotta ask…where wa the material clamp…

on the sheet

Also…why would you let it cut so much knowing there was a problem after the firs few cuts…?..

because I tested different speeds, turned off thc, and tried to save the cut.

So what I see is top dross…usually to fast of cut speed or higher amps required…you never really provided the amps you were trying to cut at…

I used 47ipm, the recommended speed in the cut chart, at 45amps

also what size of tip were you running?

OEM size

one reason I do not buy knock off tips from off shore copmanies…

that isn’t proven as the source of the problem, speculative

let me ask you was the whole sheet of wasted material and time worth the savings on you paid for cheap consumables…?..?

NOT a helpful comment

and the other thing about your pictures…what does your consumable tips look like after all that cutting?..I would think you have a possible moisture issue

i haven’t had moisture issues before today. i have an aftercooler, trap, dissecant, filter and auto drain on the tank.

see inline

[toolboy]

I made the comment about trying to save money on consumables as people seem to think they save money…I am sorry to have upset you but although you call it speculation…you fisrt made the comment and I just elaborated on it.

@mg6studios

Only other thing I can think of is that I’m pretty sure I used the “cheap” amazon consumables rather than the stupid expensive ones I got from the guy here.

so me saying top dross is a sign of too fast makes you say you used recommended speed does not make the chart right…afterall you are using a Hyperthem chart on a Razorwels…that is why I suggested you slow it down.

OEM size…are there not rated sizes for the consumables as tip size and amp rating?

why not post a picture of your consumable and tips?

I am sorry if I upset you with some of my comments.

I wish you luck…maybe someone else will be able to help you

[ChelanJim]

I would check your actual cut height.

Trouble-shooting from Langmuir suggests the following with “hunting” of the torch:

Torch ‘Bobs Up and Down’ During Cutting
https://www.langmuirsystems.com/thc/guide
If your THC settings are not properly tuned, you may notice that the torch will ‘bob up and down’ as the THC system is overhunting for the nominal voltage. Try tweaking the below settings and observe if the situation improves.

1 Increase Voltage Sample Size
2 Increase Voltage Tolerance Range
3 Lower the Z-Speed Factor

[Knick]

I have a RW and I cut 1/4” at 45 amps around 45 ipm

I would turn off THC you won’t need it on 1/4”.

Your reduced feed rate is to slow should be 60% of your normal feed rate.

Post a pic of your consumables and check with @mechanic416 for good consumables.

[holla2040]

You know how many 2" squares with a 1" centered circle I cut learning how to use my XPro, I’d say at least 30. I learned about current settings, speeds, kerf adjustment, etc. This was several days of fooling around but it helped a lot, especially for me. When I bought my XPro, I’d never actually seen a plasma torch or seen one cut. I jumped in the pool to learn to swim. The forum here helped a lot when things didn’t go well but I got the hang of it and have made about 100 things with my machine over the past 3 years.

You’ll get it, hang in there!

[Sticks]

The problems you are having on the .250 steel may have been present on the .125 and .060, you just did not know it.

Thicker metals are a different animal, and it is difficult to get that perfect almost square cut, and forget about tight clearance holes and alignment tabs without some design tweaking.

Take some of the off cuts and or scrap pieces that you did get and do some test cuts with different settings. Yes it’s a pain in the arse, bouncing back and forth from CAD/CAM to fire control, a whole bunch of different tabs in the settings windows, especially if you have to go back and forth to a different computer - but it has to be done.

Double check your work clamp connections at the plasma and the clamp.

Verify your torch cut height.

Slow down your feed rate to 30 ipm and 18 ipm on reduced feed rate. Make sure to match your lead out feedrate to your cut ipm, and maybe slow your lead in feedrate to 18ipm.

Either Hyperthem understates their ratings (45 is more like 55a) or everyone else overstates theirs. I had an Everlast 50 and after using a Hypertherm 45xp, I beleive my Everlast was more like 35 so I sold it and dropped the 2k on the Hypertherm.

When in doubt about consumables, do keep a few high end consumables on hand and in situations like this, see if the cuts still look bad with the high end. If they do, put the cheap ones back in and change your settings and conditions.

I’m not a fan of the LS-THC either. I had my run with it doing the “Bobbing” or I like to call it “Sawing”. If your material is sitting pretty level and parallel with the gantries, turn it off, especially on larger pieces. THC is a necessary evil with thin metal, but on thick, it’s more trouble than it’s worth.

Issues that you are having are fixable, you just need to find them. I’ve done the whole “Keep going, maybe it will be fixable”. Don’t. You need to stop, and get some scrap to get things dialed in on. If that means swapping out the big ass plate on the table for a small 12" x 16’ chunk, then do it. Better than creating a bunch more scrap plate for test cuts and the loss in time and money. If you think .250 is expensive, price some 1".

[ds690]

You pierce delay is too short for 1/4" material on a Langmuir table. .6 seconds may work on a different brand table, but Firecontrol calculates the delay based on when the signal to fire the torch is sent and not when the torch actually fires.

I just cut some 1/4" with my Everlast 52i and a Hypertherm Duramax torch and it came out great. The parameters that I use on 1/4" are 60 IPM, 1 second delay, .13" pierce height and .04" cut height.

The pierce and cut heights are what I determined was needed to achieve “actual” heights of .15" and .06" on my table. The cut speed of 60 IPM is only possible due to the Hypertherm torch. I was getting acceptable results at 40 IPM with my old PTM 60 torch.

[mg6studios]

I have a new pack of mechanics consumables. was using up the cheap ones first.

I didn’t go back to the garage to take more pics. I went for the bourbon. will do today.

thanks

[mg6studios]

good stuff sticks, thanks. that is my plan. I learned yesterday 47ipm was def way too fast. i was blowing through 120 at 85-100ipm at 35 amps w thc. just need to dial in 250

i did do some testing with the straight line FC generator. today i will reprogram in fusion and see what happens.

[mg6studios]

Well, thanks for the inputs gents. @Sticks @ds690. I was able to cut another base plate with much better results. Not perfect, but better. Almost no dross on top, and far less and easy to remove on the bottom.

[mg6studios]

in the bottom pic, the right plate is the first prototype cut with the huge mess. My and Grindy were at it for hours…

I did not change the consumables, so that was not the source of the problem. I did clean them.

[mg6studios]

additional note. My RazorWeld CUT45CNC is on a 30amp breaker. It has been tripping it while cutting this ¼" plate at 45amps setting (max). It has never done this before at 30-35amps.

So, I am going to change it out for a 40amp. I have 6ga wire on it already so I’m good up to 50amps.

[ds690]

Set the spring back to zero, since the post processor already adds .020" for backlash.

Also set the “pierce clearance” to zero. That is a useless setting that just adds length to the lead in distance.

[mg6studios]

Do you all typically do setups for each part in a design tool/jig or one setup for all the cuts nested up?

I had issues as you see above with nesting on ¼" steel. Using duplicate, it didn’t take long for me to do custom setups and post for each part. At least now I can cut them from the waste chunks I made earlier.

[mg6studios]

'aight, going to cut stuff… if this is a mess, I blame @ds690 …