My 4 x 8 Build

[SRdesign]

I’m almost done with my table. I’ve been working on it a few hours here and there since September. I don’t really have a lot of time right now with a new born and a 2yr old but I feel like I’m close to the finish line. I know it’s been said plenty of times, but there’s a wealth of knowledge on this forum. I can almost find any answer to any of my questions just by searching. I purchased the g5 bundle and Z axis from CANDCNC and I already have a pm85 with no cpc port. My machine torch and cpc port literally just arrived and my electronics should be here next week. Things left on my to do list are finish the plumbing on my water table, wire electronics, mount the z axis, enclose the area of the table with welding curtains and cut an exhaust fan in the wall of the shop to help extract any remaining fumes.
Some progress pics.

[SRdesign]

I guess the pics came in in reverse order

[SRdesign]

More pics

[SRdesign]

Sorry for some of the duplicate pics. I’m new to this. I did some engine turn design to the gantry plates on my cnc router just because they were plain aluminum and I thought it would look nice. At first I thought I would like the white water pan so I could see drops and see how dirty it was but I’m not a fan after painting it. But it’s not getting repainted until it needs it

[SRdesign]

Things I would do different:
1. I would do like some here have done and get a 5 x 10 sheet of 11 gauge and get it notched and bent to make the 4 x 8 water pan. I instantly regretted not doing it once I started welding the angle iron to the sheet metal. I would also make the pan 4” deep instead of 3”.
2. I would get a smaller piece of extruded aluminum for my gantry. I hope it will work fine, but we will see. If not I’ll have to modify it eventually. I didn’t stumble upon the light gantry info on this site until after I had already built it.
Other than that, so far I am pleased with the design. Gantry moves smooth and table is nice and square.

[RDillon]

That thing looks awesome. If it works as good as it looks, you've struck gold. Nice.

[acourtjester]

You may list that in the "Better Homes and CNC Tables", you sure put some work into it, very nice. It will take a while before you get the Big Smile off you face when you do the first cuts. These thing have a way of adding to your project list.

[SRdesign]

Haha, thanks for the compliments. I figured if I didn’t do everything that I thought of doing before the table was operational then it wouldn’t get done once it was up and running. Yes, I am more than anxious to get everything done so I can do some test cuts and make sure everything checks out, and I already have some “honey dos” assigned to me. A race car was taking up more dollars and square footage in the shop than this, so I sold the car and started building the table. Plus I’m the only person that can wreck the table haha.

[weldguy]

Hats Off

[SRdesign]

More progress. My plumbing is complete. I wanted to use air and drums to fill my table but I had some things laying around that would end up being cheaper and easier. I have a small transfer pump and a tank so I’m just pumping the water up to my table and when it’s time to drain I just open the drain valve. The table is full in about 9 minutes, empty in 4. I received my electronics and z axis and everything is now wired and installed. I temporarily rigged a diamond drag bit for my cnc router to the side of the torch. It basically does the same thing as the easyscriber but it’s meant for a router. I figured this would be the most accurate way to measure my travel. After calibrating the motors I was very pleased with the results. I drew a 24” square then a diagonal line from corner to corner and it is spot on. I’ll be picking up some 14 gauge sheets either tomorrow or the next day to do some test cuts. And yes, I was very excited once I got to see my table moving! I’ll be more excited when I see it cutting.

[acourtjester]

You ready for sparks good show.

[SRdesign]

More progress. Got my exhaust fan cut in the wall, no curtains yet but the fan moves air pretty good. Probably gets the curtains installed this weekend. Got my home made air dryer installed and put a motor guard filter after it. I just made one similar to others I’ve seen on here, with the multiple vertical pipe runs and a drain at each drop. Finally picked up some sheets of 14 gauge hr. They are selling for .99c a lb here in NE Florida, at least that’s the cheapest I’ve found (also not buying in bulk). Did a few test cut lines then cut a sign that I drew up

[SRdesign]

I have a few tweaks left to do on my cut speed. I had some dross on the back of that sign at hypertherm book settings. But I was pleased with how smooth the cuts were at 220ipm. I haven’t got around to using fine cut consumables yet, but I’d like to run the machine a little more and then check my consumables to make sure I’m getting clean dry air. They looked fine after that sign was cut so we’ll see.

[acourtjester]

Good Show, get yourself established with a steel supplier you will save money on metal. The place I deal with has a $50 min one sheet will cover that.

[SRdesign]

Thank you, yes I need to set up an account with that supplier, they have been the cheapest I’ve found so far. So I did notice something on my electrode when I was looking back through my pictures. I don’t know what caused it but there’s a small line going from the edge to the center. This is the same electrode that I had in doing my test cuts (which I made a few mistakes when doing, like clicking the “torch on” button instead of “disable torch”). I also did not have my home made dryer and filter installed when I was doing test cuts. I guess I could put new consumables in now and see if things look better

[SRdesign]

I keep getting a small mark on the electrode, not sure if it will show up in the pic but it’s smaller than the mark on the first electrode. Not sure what that is an indicator of but this was after cutting a few more straight line cuts and a few more of the same sign I already cut(I wanted to cut the same thing over and over so I could see differences in my settings and how they showed up on the sign).

[djreiswig]

Not sure if you're talking about the pit in the middle or something else. The pit is normal electrode wear. The center is made of hafnium. It will erode from the arc. If it gets more than about 1/16 deep the electrode is wore out. If you keep using it, the center will blow out and ruin your nozzle. I've only had it happen once, but it's pretty impressive.
If you mean the mark beside the center like in your first picture, it's probably contamination from the air supply.

[SRdesign]

Yeah the second pic isn’t as good as the first one. It looks similar to that mark beside the center but less noticeable. I probably shouldn’t have used the plasma cutter until I had all of my air setup properly(or so I think, we will see). I will keep monitoring it the next time I change the electrode to see if it gets better or keeps making marks. If so I’ll be buying a real air dryer. Thanks for your reply and info.

[djreiswig]

I've got an air drier from harbor freight. Used it from day one. I never have marks on my electrodes like that.

[SRdesign]

I think that will be my next purchase. Thanks

[Retro]

Hey man, can you tell me how thick the plates for the gantry are?

[SRdesign]

Hey man, can you tell me how thick the plates for the gantry are?

Yes, I used 3/4” 6061 aluminum plate

[Retro]

So roughly a 20 mm Plate will be enough. Is there any warpage sideways?

[SRdesign]

I placed a straight edge on my plate and couldn’t see any daylight, that’s close enough for me.
When you say warpage sideways, do you mean the plate itself being flat or when they are installed and the gantry is moving?

[Retro]

I meant the Last Part. When the whole Thing moves, does it wobble sideways or is it stiff?