MPCNC plasma cutter

[Shox Dr]

The extraction will work better if you cover up areas the worksheet area doesn't.

 

[chrisg3103]

Hello! Can you help? My MPCNC has a backlash of 2 mm axis z. If not laziness, share STL under the thrust bearing and the size of the bearing for ordering, as well as the blue T8 coupling, please.

Hi, try this - https://www.thingiverse.com/thing:4079935

Bearings are F8-M16 and coupling is just a 5 - 8mm

 

[Vlad]

Thanks! It looks like.

 

[thinfourth]

Hi, try this - https://www.thingiverse.com/thing:4079935

Bearings are F8-M16 and coupling is just a 5 - 8mm

OOOOOoooooHHHhhhhhh

This is exactly what i am planning on

Do you do phone a friend?

 

[chrisg3103]

Anything you want to know that I havnt posted here feel free to ask. Really need to update this

 

[Dev]

You don’t fancy sharing the files for the cable management mod do you? I’ve lifted mine onto the bench to try and motivate me to finish it and I think I’m going to have to redo all the cabling

 

[chrisg3103]

Can do, I'll see if I can locate the stl's and post them on thingiverse later when I get a chance. Any progress is progress!

 

[Dev]

Cheers that'd be great. https://www.prusaprinters.org/prints is a good alternative for thingiverse btw.

I've a leadscrew, coupler and nut on its way from amazon to finish the Z assembly (when I printed it all it was M8 threaded bar)

But now I've seen this: https://www.thingiverse.com/thing:3036995



And I remembered I saved a load of 4545 from the skip a while back so I'm printing new feet now too. Probably worth printing the mid-span supports as well. Gaaah it never ends

 

[thinfourth]

Anything you want to know that I havnt posted here feel free to ask. Really need to update this

What RAMPs board would you buy if you were doing this again?

My current plan is to get the tube first and then start printing the bits and building the machine

 

[chrisg3103]

Cheers that'd be great. https://www.prusaprinters.org/prints is a good alternative for thingiverse btw.

I've a leadscrew, coupler and nut on its way from amazon to finish the Z assembly (when I printed it all it was M8 threaded bar)

But now I've seen this: https://www.thingiverse.com/thing:3036995

View attachment 229229

And I remembered I saved a load of 4545 from the skip a while back so I'm printing new feet now too. Probably worth printing the mid-span supports as well. Gaaah it never ends

Looks interesting, think i have located all the files, if anythings a bit off it might be one of the development ones. I am quite bad for not deleting old versions when i find the final form so often have about 6 versions of the same part with imperceptible changes

https://www.thingiverse.com/thing:4356114/files See how this goes.

not used prusaprinters before but looks interesting, put it on thingyverse as i already have an account.

What RAMPs board would you buy if you were doing this again?

My current plan is to get the tube first and then start printing the bits and building the machine

I have been having lots of interference issues with the arduino resetting all the time, so ended up buying a genuine arduino! think it helped a little bit but might be a placebo thing
Think i have traced the worst of the interference coming from the power/air hose to the plasma torch, after may frustrating board crashes i inadvertently moved the hose out the way of something and tried again, worked flawlessly! working on a shielding type thing for the plasma hose out of metal kopex.
So i think the cheap ramps setup will probably be ok but if i were to do it again i would spend the extra for a better quality setup, failed cuts are incredibly frustrating

 

[chrisg3103]

So here is a bit of an update on recent(ish) stuff, one project i had for both the plasma and router functions was to make a control panel for my lathe.
Step one design layout of buttons and displays, then cut out of aluminium on the plasma.

Then simply load it into estlcam and make a CNC program, simple!

ehhh naw! i count roughly 10 failures here, faces are just tests to make sure the program wasnt corrupt.
after about 2 days of trying to figure out why it suddenly got so bad i had an idea, i had been running it from SD card and the little display on the ramps board. It sort of looks like the interference from the plasma was corrupting the data stream from display to main board it either crashed and just froze as the whole thing reset of got random movements as seem above.

So changed tact, a long usb cable, unplug the display and run the machine through repetier host.

And it worked! sort of, plate warped and the torch got stuck, lost steps and its a bit trapezoidal
but making progress.

tried again and was a bit preplexed why the plasma was cutting so rough, then i found the earth clamp sitting on the shelf very impressed it cut the entire plate on the pilot arc! needless to say the pilot arc wire was very warm after that.

3rd time lucky, earth clamp attached and plate clamped down!

step one done, could of easily cut it out by hand in half the time but it turned into a mission.

step two was cut out the front of the panel from engraving laminate, dont have any pictures of it engraving so here is the finished article

 

[chrisg3103]

Looking back at those pictures with new perspective i think this is the main culprit of the failures:

by the arrow is the ramps stack contained in what i was hoping to be a shielded box, but as you can see the plasma power cable is running right beside it....
After some other failed cuts a little while ago i found by moving this away from all those sensitive electronics it helps, that cable is probably spewing high frequency emf when the plasma is firing.
Probably common sense to some but we all have to learn somehow!

 

[rourkek4]

Well done! I really really want this to be a good, fiddle free machine for hobbyists so that i can follow you! did you engrave the laminate on it too?

 

[chrisg3103]

indeed, i have a spindle i can mount and clamp a board to the table.
I dont think anything like this will ever be fiddle free though, if you want reliable repeatable performance you need to spend some money i think! Its a fun little side project, dont have much time for it at the moment unfortunately but ill try to keep it updated if anything happens.

 

[rourkek4]

Completely understood. I'm not quite sure that will stop the tinkerer in me from following you down the rabbit hole either though!

 

[Munkul]

Excellent progress, following this with interest

 

[thinfourth]

Well mine moved under power for the first time today

but it is still very much in lash up stage as it was one servo on the X axis with movement being limited by the length of the cable on the stepper

And i might using string instead of cable ties

The other part of the project is getting a windows laptop up and running i forgot how annoying i find windows

 

[chrisg3103]

Any progress is still progress! Think you can get little velcro cable tidy things if you plan on cable tinkering?

 

[thinfourth]

Found a post saying to add the command G4 S0.7 to the cut start command, this is supposed to start the plasma and pause the program for 0.7 seconds to let it pierce, sounds good, didnt work! But think in hindsight its because i wrote g4 s0.7 think capitals matter

the G4 command

Are you adding that manually to the code or are you getting estlecam to add that?

What are you using to switch the plasma on and off?

As i have got to the stage where i can design something in Fusion 360 export it as a DXF and then draw it using a pen

So next is either a cheapo router or get the plasma to work

 

[thinfourth]

ALSO

if anyone wants the parts printed drop me a line and i can do a set for you