Since you asked. LOL
It is actually listed as the last line instruction under the “Water Table Assembly” instructions for the Original CrossFire table.
Someone following the Pro instructions would be taken there through this link:
They are now in Original CrossFire instructions.
If they were to page up slightly for some reason, they would find it as the line just before the “Laptop Stand Assembly” instructions.
-Steve
PS: In no way do I agree with it, just pointing out where it says it.
@GeoJettson, I also posted this screenshot (but from my phone) in post # 7 or 8 above, but a few folks commenting seem to have missed that. I must have clicked the same link you mentioned to wind up there from the Pro instructions, because that’s definitely where I started.
FOR THE RECORD: I thought the recommendation seemed strange, BUT, as a complete novice to plasma and CNC anything, AND knowing all the troubles I have read about people having with electrical interference, there was NO WAY that I was going to second guess Langmuir’s instructions.
Maybe @langmuirsystems will chime in with why that grounding location was recommended? My cut quality seems like it has improved slightly grounding directly to the work, but it’s still pretty far off. Waiting for more consumables so that I can continue trying to dial it in.
Wonder if LS forgot to change the manual?
@CrazyCasey , It was actually your screenshot that prompted me to try and find it. Once I did, I couldn’t help but find how someone who’s obviously paying attention to detail, such as yourself, could have ended up coming across it elsewhere.
Also, watched your video with the silicone torch shield. Just received a couple yesterday from Amazon after getting the part number from @TortillaMan. Taking my time putting my Pro table together, but once I’m up and running, I plan to try using the shield in the flatter, collapsed configuration. Just to try to catch significant upward splashes without dragging across and hooking the part. -Steve
I was going to make another video saying NOT to use those funnels, Steve. Yeah, I know it looked terrible dragging on the part in that first video, and I of course fixed that on the next cut, doing as you said and folding it up slightly. But on the next cut, which was 3/8” material, there were a lot more sparks and that silicone funnel caught fire and ruined the nozzle holder on my machine torch. I’m not sure if it’s the cheap Chinese silicone, or what? That stuff isn’t supposed to catch on fire, but it did, and what a mess it made when it did. 
@CrazyCasey Yikes!
May need to rethink that whole idea. Thanks for the heads up!
Perhaps we need one of those MR1 guys to design and sell some nice aluminum torch shields?
Anyone out there looking to pay off there MR1?? -Steve
Granted, my torch is cutting too high so I’m having issues with topside dross and incomplete pierces, meaning more sparks than normal, but…
Did you ever run the program to set your cut height?
I did, @Knick. And I’m more confused than ever.
@Phillipw, you said your Line Test TAP file was set to 0.060" without any spring back. After getting some weird results on sheetmetal, I started running the test to set IHS off an arbor plate in the middle of my table (right between two slats so there is ZERO deflection. I am also running to the top of the Z-axis prior to running the test, so that backlash is minimized as a variable. With your program I am getting a cut height of 0.084".
BUT, that’s not the weird part…
@ds690, your IHS Cycle NC file test is supposed to have an added 0.040" factor for spring-back and backlash. Parameters as above on the test of Phillip’s TAP file, and I’m running to the exact same spot on the arbor plate. I’m getting a cut height of 0.065".
The results of @Phillipw’s test would suggest I need to LOWER my desired cut height parameters by 0.024", which sounds logical, given the cut quality and consumable life I’m experiencing.
The results of @ds690’s test would suggest I need to RAISE my desired cut height parameters by 0.035", which I know is incorrect, BUT, why am I seeing this discrepancy in my results, fellas?
For what it’s worth, I ran both tests at least a half dozen times. And I re-downloaded BOTH files to make sure I didn’t have them mixed up; 0.084" cut height on the test that jogs right before plunging…that’s @Phillipw 's test.
Oh…and also, I just realized that my swirl ring was installed incorrectly in my torch from the factory, so that could be accounting for some of my cut quality issues.
actually mine was set at .020 backlash
Aplogies for the confusion. I just looked at the file I posted and noticed that the .040" springback/backlash is in the code, but commented out with parentheses. That means it won’t actually execute that line of code, so the file should result in a .063" torch height with a zero backlash setting. Your finding of .065" is very close to that and indicates that you should set your springback to zero.
The finding with Phillip’s file also confirms that you should set the springback to zero, since his file includes a .020" springback.
Just note that, on thinner flexible materials, you may need to set a springback value.
the swirl ring being installed wrong will definitely jack up the cut quality.
Hey Steve…
thanks for the link…but this is where the confusion is for people…
It does talk about attaching the ground to the water pan…but the ground from a plasma cutter is not the material clamp…there actually is on many plasma units and bonded ground on the back of the case to ground to the table…this is what the line refers to
the material clamp is not a “ground”…read this thread…
it can be mistaken by many…and many have made the same mistake
what is not great is the fact that the pictures show a plasma torch being used on the tables…but it does not show the material clamp on the metal being cut…which adds to the confusion of the whole thing…
but always remember there is a material clamp from a plasma unit…not a “ground” clamp…
I will try to flag this up the line for possible changes to some of the wording Langmuir uses in the instructions…
@toolboy Awesome! And thanks for the lesson. I figured (ASS-U-ME’d) that the terms were interchangeable, but when are terms in a technical manual EVER actually interchangeable…? At least they are not in a well-written one.
@ds690 & @Phillipw, I have never been so happy to hear that I was given incorrect information (and misunderstood the information I was given). And what are the odds that it was in opposite directions!
The best part is that it sounds like my machine is behaving correctly!
So with the gro…err…MATERIAL clamp in the correct place, and with the swirl ring installed correctly, with the IHS spring-back programmed out of the cut file, and with reduced speeds on inner geometry programmed IN, I should accomplish a relatively clean cut!
Holy Heck I’m excited! Picking up some steel tomorrow, and I’ve got some fresh consumables arriving Tuesday. Now, if the dang electricity stays on, we’re going to have ourselves a PARTY! 
glad you got it figured out but what info did i give you incorrectly?? i never specified any backlash or not.
You ARE correct! I was asking about IHS spring back and you didn’t say whether yours was set with backlash or not. Chalk it up to me not knowing enough about these settings and the related terminology, I guess. I was looking for 0.060" instead of 0.080", and Dave told me his IHS test file was set with 0.040" IHS/backlash combined so I was looking for 0.100" instead of 0.060". Turns out both were dead on the money! My apologies!
i did say that it was set at .060 no mention of backlash then i reponded to knick and said.
The program I sent you had .020. No need to account for spring back where the torch is is where it will cut. The purpose of the spring back is to take the slack out of the lead screw since it isn’t a anti backlash.
I just saw that reply to Knick and corrected my above post. 
Apologies @Phillipw.
Well that’s not completely right either
AC will work with out a ground. the ground is for safety.
I can see the confusion I guess but I think most people think of that cable as a ground.
So is there a spot in the manual where they talk about the material clamp placement?
When I ran Phillip’s program I got the same results as you. I was a little over .020 high
