CandCNC or Plasma Table New User Help

[lt1yj]

I'm a noob at CNC plasma and jumped in with both feet. I picked up a used Torchmate 3 table and dumped the electronics and opted for a CandCNC retrofit with the feather touch Z axis and ohmic sensor on the torch. Hypertherm 85.

Just got the electronics assembled and got it calibrated in X,Y and Z and everything seems to work pretty well. Threw some 20 gauge down and ran 3 test cuts of various sizes to check for square and size and it cut amazingly well. Way better than I expected out of the box.

Next I jumped to 11 gauge to run some thicker tests and promptly ran into issues. The control came preloaded with presets for the Hypertherm plasma cutter and I can choose the correct material thickness and torch nozzle to preset the voltage and air pressure of the plasma cutter. Unfortunately, there's no 11 gauge with a Hypertherm 65 nozzle, just 10 and 12.

When I pick 12 gauge the torch pierces the material really well but after 2-3" of travel pulls off the plate about 1/2" and just gouges the material. When I choose 10 gauge the torch pierces cleanly and then dives into the plate after 2-3" and then I get a Z axis fault.

I created a custom preset and haven't been able to get rid of the torch pulling off the plate or diving into the plate.

Can any experienced users help point me in the right direction? I get the feeling this is a trivial setting issue but I don't know what knobs I'm turning incorrectly.

 

[AK_F250]

First cut with the thc off to get a baseline arc voltage and make sure its just a thc issue. I've used there stuff on several table builds and retrofits and they've all had some weird quirks that needed to be worked out. Your z axis might be inverted (or not) in the hub admin which makes the z do the opposite of what the thc is calling for. Turn the sensitivity down in the admin too and see if that helps. Ground loops are also a big thing, make sure your ground lead isn't coiled up on the table or crossing any other ground. How do you have the table grounded?

Edit: Just to illustrate how sensitive these can be to interference, my brand new 30k arclight table with candcnc's command cnc package would do exactly what your table is doing right out of the box because the plasma ground was laying wadded up on the ground wire going to the ground rod.

 

[ThePanzerFuhrer]

Did you set the free travel amount in the program to take in account of the switch travel movement? From. My buddies table it’s some option and I think I remember you have to make it negative.

 

[AK_F250]

Did you set the free travel amount in the program to take in account of the switch travel movement? From. My buddies table it’s some option and I think I remember you have to make it negative.

Thats the switch offset parameter, and if it's piercing and cutting a bit probably not the problem since if that was off much it would bury itself in the plate or fire the torch too high right off the bat. The default for the thc to turn on should be 3 inches of travel iirc, so once it's taking over control is where he's having issues.

 

[SomeGuyFromOlympia]

I have a TM table paired with a HT 85
Just so you know, the HT book specs are spot on, just go off of the charts and don't second guess them

You have the basics enough air? Dry Air? Enough CFMs?

Going on the above advise, the table is actually a bunch of individual components that work as one big tool
CAD design
line code
table mechanics (gears/belts/everything is square)
THC
Plasma machine
air supply

when you have problems, isolate that problem and then it is easier to home in on it

and 20Ga is going to be smoking right alone as far as ipm on that machine
if you have some sacrificial .25 you can slow down quite a bit turn the machine down to 45 and you will have time to actually comprehend what is happening. When the torch crashes, you will be able to catch it hopefully before it happens

 

[lt1yj]

I don’t have a separate ground from the table to earth, just the ground clamp from the plasma cutter to the plate. Plasma ground cable is haphazardly laying on the floor near the control. I will have to check if it’s near any control leads. We don’t have everything buttoned up yet. We wanted to make sure it was working correctly before cleaning up the wire routings.

The PWM module is either reading 0 volts or 245 volts when in auto. When we push the test button it shows 127 volts which is exactly what the manual says.

In manual thc mode it reads 0 volts.

We found a reference in Candcnc PWM trouble shooting that indicated the cable to the CPC port or the voltage divider could be bad.

I installed the CPC port and voltage divider. Seemed pretty straight forward but I’ll check it out tomorrow.

What should the pierce height and cut height be? We played around with the settings tonight and got some pretty nice 6” long cuts in 11 gauge and then ran a 6x12 rectangle and it went back to moving off the plate after 3”.

 

[lt1yj]

I have a TM table paired with a HT 85
Just so you know, the HT book specs are spot on, just go off of the charts and don't second guess them

You have the basics enough air? Dry Air? Enough CFMs?

Going on the above advise, the table is actually a bunch of individual components that work as one big tool
CAD design
line code
table mechanics (gears/belts/everything is square)
THC
Plasma machine
air supply

when you have problems, isolate that problem and then it is easier to home in on it

and 20Ga is going to be smoking right alone as far as ipm on that machine
if you have some sacrificial .25 you can slow down quite a bit turn the machine down to 45 and you will have time to actually comprehend what is happening. When the torch crashes, you will be able to catch it hopefully before it happens

80 gallon Ingersol Rand T30 with a refrigerated air drier plumbed into a 60 gallon holding tank with 80’ of 2” black iron pipe to a water separator, filter and a huge desiccant drier right before the plasma cutter.

I ran this same setup with a hand torch and it cut 1/2” plate pretty well.

The table has some quirks still. The gantry is ~1\8” off plumb because the table slat holders are off by 1/8”.

I designed née slat holders but need the table to work first.

We’re focusing on the arc voltage sensing issue right now. It seems to control what the Z axis does in auto mode.

 

[lt1yj]

I should have said we can get clean cuts with manual torch height control.

The issue only shows up in Auto THC mode.

The 20 gauge curled and warped all over the place. I don’t think manual THC would work that well. We didn’t try so I could be wrong. The 11 gauge curled very slightly and manual THC worked fine.

 

[SomeGuyFromOlympia]

I should have said we can get clean cuts with manual torch height control.

The issue only shows up in Auto THC mode.

The 20 gauge curled and warped all over the place. I don’t think manual THC would work that well. We didn’t try so I could be wrong. The 11 gauge curled very slightly and manual THC worked fine.

I honesty don't use the arc voltage feature all that much, I use "manual mode" .....torch comes down, touches, retracts, pierce, moves to cutting height and stays there.
Personally I seem to get better parts this way BUT, I run a water table so the parts don't get as hot, and warp I bring the water right up to the plate
full disclosure, I hardly ever cut less than .25 also, but I treat 10Ga the same way

If you can get cutting good in manual mode, then I would go chase the auto voltage adjustment AFTER you know your height/speeds/table setting are correct

When you are in auto, it will want to dive at the ends of cuts searching for the voltage that it lost, and it happens around corners too if it is set to slow the cut in the corners. Mine doesn't have a corner lock out like some tables do, but my equipment is considered old by today standards

edit:
sounds like your air supply is good, so cross that off the list

 

[AK_F250]

I think the divided voltage board in your plasma is shot if you're getting zero cutting. I've had two hypertherms that had them fail, a powermax 45 and 85. Or the PWM module connected to the plasma could be bad, I got a bad one out of the box from them once. It's easy to test the pwm and plasma for the proper output with a meter.

If you've never cut with the thc on you could have any number of issues. Did you check the direction of your z axis in the hub? I didn't realize that you'd never used the height control and it could be a number of other things I didn't bother to mention.

 

[lt1yj]

I think the divided voltage board in your plasma is shot if you're getting zero cutting. I've had two hypertherms that had them fail, a powermax 45 and 85. Or the PWM module connected to the plasma could be bad, I got a bad one out of the box from them once. It's easy to test the pwm and plasma for the proper output with a meter.

If you've never cut with the thc on you could have any number of issues. Did you check the direction of your z axis in the hub? I didn't realize that you'd never used the height control and it could be a number of other things I didn't bother to mention.

Hypertherm tech support was very helpful. With their help we verified the voltage divider is working correctly and the main board (J32) port is also working correctly. I was able to pull 3.4V between terminal 5&6 when the torch was activated in air, which is a little higher than the 3.2V spec but reasonably close.

Candcnc got back and pointed to the cable or the voltage divider.

I'm supposed to get a call back in the morning but I'm pretty sure it's the cable. Their instructions show I should be pulling from terminals 5&6 for the voltage divider (so does Hypertherm) but the cable is wired for terminals 12&14. CPC cable plug is rotated 90 degrees in the pic. 12&14 are on the right.

Of course none of my depinning tools will fit those terminals and I couldn't get the pins to release with my redneck welding wire method either.

Ran some more 11 gauge test cuts in manual THC mode with a 65 amp nozzle and it's cutting well. Tomorrow I'll try out the 45 amp and fine cut nozzles that were delivered this afternoon. I'm still a little off square but less than 1/64" over 6". Should get that dialed in in the next day or so.

Do you see anything I should be concerned about with the cut pics? The dross looks pretty reasonable for an air table in my limited experience. I ran this at 1/2 the recommended travel speed just to check voltages for Hypertherm. The corner shown is the lead in / lead out.

Thanks for the feedback. It's been really helpful.

 

[lt1yj]

I honesty don't use the arc voltage feature all that much, I use "manual mode" .....torch comes down, touches, retracts, pierce, moves to cutting height and stays there.
Personally I seem to get better parts this way BUT, I run a water table so the parts don't get as hot, and warp I bring the water right up to the plate
full disclosure, I hardly ever cut less than .25 also, but I treat 10Ga the same way

If you can get cutting good in manual mode, then I would go chase the auto voltage adjustment AFTER you know your height/speeds/table setting are correct

When you are in auto, it will want to dive at the ends of cuts searching for the voltage that it lost, and it happens around corners too if it is set to slow the cut in the corners. Mine doesn't have a corner lock out like some tables do, but my equipment is considered old by today standards

edit:
sounds like your air supply is good, so cross that off the list

We've been playing with the manual torch settings and are making progress.

A water tray is in the future. I have a backlog of stuff to make for my wife and daughter, as well as a bunch of stuff I want to make for my Jeeps.

I'm sure this will change but I'm planning to run 11gauge to .25 mostly in the short term.

 

[SomeGuyFromOlympia]

Do you see anything I should be concerned about with the cut pics? The dross looks pretty reasonable for an air table in my limited experience. I ran this at 1/2 the recommended travel speed just to check voltages for Hypertherm. The corner shown is the lead in / lead out.

If it were me, I would step down to 45A, set it to what the book says

I know the bigger gantry's don't like the fast directional changes,(mine doesn't anyway)

You got it, just give it time

 

[AK_F250]

Those cuts look great, you’re just going through the usual growing pains. Shoot me a pm if you want my number to chat, chances are I’ve been through anything you might come up against.

 

[lt1yj]

If it were me, I would step down to 45A, set it to what the book says

45 amp nozzles and fine cut nozzles should be here tomorrow (USPS is holding them hostage). I only had 65 and 85 amp on hand and wasn't thinking about using thinner material for the test cuts.

Waiting to hear back from CandCNC. I got a very confusing message from them last night and I'm hoping it was in error and we can work it out today. I've heard good things about their customer service but haven't personally tested it out.

Probably doesn't help that I'm not very familiar with their hardware and probably interchanged Hypertherm terms for CandCNC terms and that threw another layer of confusion into the mix.

 

[lt1yj]

The cable above is not the right cable for the DTHC I have. CandCNC is sending me the correct cable with pins 5&6 added. Probably won't get it for a week or so. We played with squaring it some more and got bored and wanted to run some test runs for actual parts.

Made a license plate holder for my trailer. The holes turned out really bad. no pics. Second run got better but still pretty bad. I ended up reaming them to size. The outside profile was really nice.

I had to run an errand and when I got back my son made these. The holes are still a little rough. Hopefully we can get the fine cut nozzles tomorrow to test out on Sunday and work on feeds and speeds as well as lead ins.

If you look close there is a wobble in the first smile and around the bottom of the face. I've noticed it in a few sample cuts. Is this table related or electronics? I'm leaning towards table. I'll have to check the rails and racks for issues.

Any advice on how to improve the cut in the small holes?

 

[ThePanzerFuhrer]

If your smiles were cut with the y axis running up and down through the face and x axis across the face left to right it looks like you have some backlash in the y direction. The wiggle looks like it occurs when you changed the y axis direction.

 

[lt1yj]

If your smiles were cut with the y axis running up and down through the face and x axis across the face left to right it looks like you have some backlash in the y direction. The wiggle looks like it occurs when you changed the y axis direction.

That's exactly how it was cut.

I reset the rollers when we were setting the gantry perpendicularity. All four seemed to be pretty snug. I'll have to check the rack to see if the spur gear is fully engaged along the travel.

 

[arse_sidewards]

Choose a different font for your emojis so you don't need the stupid hole at the end.

Any idiot can design parts that work. It takes a brain to design parts that can also be manufactured.

 

[lt1yj]

I think I found the Y axis problem but won’t know for sure until Sunday.

The spur gear on one side rubs against the beam in a 12” long section. I spaced it out so it sits in the outside 1/2 of the rack. Hope it’s this simple

 

[SomeGuyFromOlympia]

I think I found the Y axis problem but won’t know for sure until Sunday.

The spur gear on one side rubs against the beam in a 12” long section. I spaced it out so it sits in the outside 1/2 of the rack. Hope it’s this simple

any idiot that hasn't been though the process of getting a new table set up will have opinions on stuff that they clearly don't understand what they are commenting about

little adjustments, you will get there

 

[lt1yj]

any idiot that hasn't been though the process of getting a new table set up will have opinions on stuff that they clearly don't understand what they are commenting about

little adjustments, you will get there

Thanks. It’s rewarding and frustrating at the same time. I’m still at the bottom of the learning curve but it looks like a lot of fun when we get to the first peak.

 

[ThePanzerFuhrer]

I think I found the Y axis problem but won’t know for sure until Sunday.

The spur gear on one side rubs against the beam in a 12” long section. I spaced it out so it sits in the outside 1/2 of the rack. Hope it’s this simple

Good deal, you’ll get it figured out. Once you learn the specifics of your machine it becomes super easy

 

[lt1yj]

So.... It wasn't that easy.

I've been tweaking and adjusting and fine tuning and have most of the wiggle gone. It still pops up in random places and I haven't found the culprit.

Here's the final cut for today. Old smiley on the right. Fine cut consumables with 150ipm feed rate. I'm pretty pumped about everything except the wiggle on the left side of the tongue. We cut two others and the wiggle was in a slightly different location in the smile itself. The outside looks perfect. The right eye has a very slight wiggle that is hard to see. The left eye is really clean (it looks wonky in the pic but not in real life).

Hard to believe I was happy with the one on the right last week.

Tomorrow we're running holes. Lots of holes of different sizes trying to dial in the settings and to find where the wiggle is coming from.

 

[SomeGuyFromOlympia]

So.... It wasn't that easy.

I've been tweaking and adjusting and fine tuning and have most of the wiggle gone. It still pops up in random places and I haven't found the culprit.

Here's the final cut for today. Old smiley on the right. Fine cut consumables with 150ipm feed rate. I'm pretty pumped about everything except the wiggle on the left side of the tongue. We cut two others and the wiggle was in a slightly different location in the smile itself. The outside looks perfect. The right eye has a very slight wiggle that is hard to see. The left eye is really clean (it looks wonky in the pic but not in real life).

Hard to believe I was happy with the one on the right last week.

Tomorrow we're running holes. Lots of holes of different sizes trying to dial in the settings and to find where the wiggle is coming from.

how big is your table? Or did I missed it somewhere posted already ?

150 is fast for the bigger tables, big gantry's anyhow

but looking good

I used mine yesterday, and I have a loose something starting to happen, I need to track it down

 

[lt1yj]

how big is your table? Or did I missed it somewhere posted already ?

It's 5'x10'

We ran a series of smaller holes from 3/4" dia down to 1/2" at 90 ipm and 60 ipm and the cut quality started to fall aprt at 9/16" and was pretty bad by 1/2". Goal was 1/4" but we aborted at 1/2".

More test cuts tomorrow. Looking forward to more progress. I'm probably running a few 3/8" thick chain hook plates for my trailer tomorrow. I want to test them out while the trailer is apart and it seems like a good time to start dialing in the thicker materials.

 

[SomeGuyFromOlympia]

grab your torch with your hand and try to wiggle it
if there is any play it will show up in circles. You are looking pretty close

I have the same size table, I run the slowest settings that I can find, that is a lot of weight to be changing directions at 150 ipm

grab the book, and set it by the book for your cutting parameters and run with it

I wouldn't get your hopes up for 1/4" holes though

 

[lt1yj]

grab your torch with your hand and try to wiggle it
if there is any play it will show up in circles. You are looking pretty close

I wouldn't get your hopes up for 1/4" holes though

That's how I found my X axis belt wasn't tight enough.

I also found a loose bolt in the Y axis rack that I thought could be causing backlash. It's getting better but not quite there yet.

For smaller holes I'll probably just pierce the center and step drill to size. It's not like I'm doing production, this is just for my own use.

Thanks for the feedback.

 

[SomeGuyFromOlympia]

For smaller holes I'll probably just pierce the center and step drill to size. It's not like I'm doing production, this is just for my own use.

On the little stuff this is how I do it

on that note Cobalt bits deal with the nitride hardening better than plain ol bits

 

[Dethmachinefab]

on that note Cobalt bits deal with the nitride hardening better than plain ol bits

Car reamers work well to finish out plasma holes. Fast and last longer.