Johns 4x4 Plasmabot 4.0 Build Thread

[jeepsterjc]

Hi John. How's the bed liner working out? I'm almost to closing the corners on my water bed and still undecided what to finish coat the thing with.

[johndjmix]

jeepsterjc: AMAZING. Cant even be compared to paint. In fact, its working so good i might find myself using it on other things. It does seem to take a few days in the sun to dry real well so it doesnt chip off though so make sure you put the table outside to dry for a few sunny days.

ajclay: I would think to agree on the chart, but ill tell you right now, for this machine...no way. Max I can cut 1/4" at is ~30ipm.....any more and i lose penetration (Or was that what my girlfriend said? -).

And voltage seems to be happy ~80. According to everlast my machine should be at 88-100V.

--John

[jeepsterjc]

jeepsterjc: AMAZING. Cant even be compared to paint. In fact, its working so good i might find myself using it on other things. It does seem to take a few days in the sun to dry real well so it doesnt chip off though so make sure you put the table outside to dry for a few sunny days.

ajclay: I would think to agree on the chart, but ill tell you right now, for this machine...no way. Max I can cut 1/4" at is ~30ipm.....any more and i lose penetration (Or was that what my girlfriend said? -).

And voltage seems to be happy ~80. According to everlast my machine should be at 88-100V.

--John

Hey John. That's good to know that the bed liner is working out. What brand/product did you use? I may as well go the same route. I had been worried that the plasma arc might get into it along the edges of the table... , but that would be really rare, and the smoke cloud would be extra toxic. My lungs are more important than my water bed!

I'll be shopping for liner I guess! 2-part stuff?

BTW- you're doing a an awesome job.

You're weeks ahead of me. I'm all the way up to pg 60 in the candcnc manual!! Oh yeah!

[johndjmix]

jeepsterjc: Give me a call tonight (ill be up till at least 3AM EST playing with the table). I have a few things that will save you TONS of time and wasted material.

ill PM you my cell...

--John

[xalky]

John: I've seen your posts over at the CandCNC yahoo group, I'm assuming it's you. because they're almost identical to the posts and issues you posted here here. I know you're running an Everlast machine. I'm running a Longevity machine which are similar...almost identical actually. I'm not clear on how the THC works when pilot arc is on, or does it. In my mind it seems that the voltage would be steady as long as the pilot arc is engaged seeing as the gap between the electrode and pilot ground on the torch are consistently the same regardless of distance to the material being cut...What am I missing? Should we be using pilot arc with THC?

[johndjmix]

xalky: Fron what I understand, not too long ago everlast switched their company direction, as they were basicly coming out of the same factory as most chinese plasma cutters. Now they say customers wanted a more "comercial" unit, which is is. Looks way different than the older ones and seems to work good....except for that arc-ok.

You would think as long as it has a good arc to the material it would stay on...but it doesnt...it flickers. You can watch it durring the cut flicker, sometimes it wont be off for long enough for the machine to see it and stop, other times it will. Now, if it loses arc i simply go press the torch button in mach3 off and then on, and it gets the indicator back and continues cutting. I can tell you this, since i jumped it...no problems. This proves to me its somthing in the everlast and not in the computer/candcnc. All candcnc wants to see is a contact closure!

A few nights ago after having to turn the torch on and off 8 times in one cut i gave up. I jumped the "ac-ok" wires that go into the DTHC together. That gives me arc-ok at all times. So far this works fine. I dont see any downfall to it, except that the torch will keep moving if it was to loose arc...but, lets face it, that shouldnt happen ever unless you screw up. And if it does, big deal, edit some g-code and continue where you left off.

Im planning to get a Hypertherm45, but until i have an extra 2k to spend it wont be happening.

--John

[Torchhead]

xalky: Fron what I understand, not too long ago everlast switched their company direction, as they were basicly coming out of the same factory as most chinese plasma cutters. Now they say customers wanted a more "comercial" unit, which is is. Looks way different than the older ones and seems to work good....except for that arc-ok.

You would think as long as it has a good arc to the material it would stay on...but it doesnt...it flickers. You can watch it durring the cut flicker, sometimes it wont be off for long enough for the machine to see it and stop, other times it will. Now, if it loses arc i simply go press the torch button in mach3 off and then on, and it gets the indicator back and continues cutting. I can tell you this, since i jumped it...no problems. This proves to me its somthing in the everlast and not in the computer/candcnc. All candcnc wants to see is a contact closure!

A few nights ago after having to turn the torch on and off 8 times in one cut i gave up. I jumped the "ac-ok" wires that go into the DTHC together. That gives me arc-ok at all times. So far this works fine. I dont see any downfall to it, except that the torch will keep moving if it was to loose arc...but, lets face it, that shouldnt happen ever unless you screw up. And if it does, big deal, edit some g-code and continue where you left off.

Im planning to get a Hypertherm45, but until i have an extra 2k to spend it wont be happening.

--John

A couple of things here: I have seen the voltage being off from what it should be in other Everlast and Longevity units....I suspect the internal divider is done different than the Hypertherm and TD units we work with. If it bothers you then find the section in the manual on calibrating the DTHCII module at the 127 to 128 range and raise that point with the calibration pot so the reading is closer to the values in the chart when you are cutting. Just figure what the ratio of increase should be and then apply that to the test voltage value. Make sure you are using the right consumables and using the the right arc gap (standoff) or the voltages can vary. You just end up rescaling the readout. Should be enough adjustment to move it up to the right range. You can easily put it back with the built in calibration test if/when you get the 45.

Another suggestion: Get our DCP-01 Digital Current Probe and put it on the workclamp lead. Slides on the wire. It will then readout the actual cutting current on the MACH screen AND you can use it for ARC OK. It will let you know what is going on with the current. Make sure you have the workclamp to the material you are cutting, not just clipped to the table.

If the unit is not holding constant current then it's not ever going to cut right. the current on my 65 is within an amp of the setting on the machine and stays rock solid.

[johndjmix]

Thanks Tom. I've just really played with it enough to mess up. I think I have the voltage at a spot where it seems to be dead on. Maybe it's me, but when the tip starts going bad on the gun, things go all over the place.

Any disadvantage to keeping that "arc-ok" jumped?

--John

[xalky]

Thanks for the reply John. And Tom.
Tom will a regular wrap around amprobe work to get an amperage reading. I have one kicking around here somewhere.
The CandCNC setup is a really nice well thought out system and the user manual is the cats meow. I really feel sorry for some of these guys that are trying to save a few bucks and engineer the electronics themselves. It makes no sense to me. The user support and user manuals and macros are are well worth the few extra bucks not to mention that these systems are all tested before they're shipped.

Tom:You guys are putting out a great product, I wish you lots of success.

John: Didn't mean to hijack your thread

[johndjmix]

I look at it this way. If you have a crazy amount of free time, are real real good with electronics and want a fun project, go for it and make it yourself.

For the rest of us candcnc is the way to go. There are so many things to learn and setup, i can't imagine the time it would have taken me if I didn't go with the candcnc product!

--John

[johndjmix]

Got my table painted and wired everything up nice. Note the DB9 plus hanging just under the candcnc. I didnt like the way the limit switchs connect to the candcnc box, since basiclly you need to cut off the connectors to remove the box, and connecting each is a pain. So... i wired them from candcnc into a DB9 port and wired the table limit switchs into a male db9.

Tom, if you read this....curious....why not have one of those little green connectors on the outside of the box for the limit switchs?

[jeepsterjc]

Wow John. Your table looks awesome. Way-to-go!

I've got to drill my Y-rails down and am already things about how numb my hands and arms will be before I'm done. What size were your pilot holes?

Thanks,