A lot of people don't use a metal enclosure so in which case the single point ground is the best option, but a grounded case is the safest option.

something that just occurred to me also is its worth buzz testing the ground terminals and case of each component before bolting into your enclosure, if you find an already grounded case on a component and bolt to an enclosure, you need to either not attatch a ground as it grounded already through the case, bolt to your enclosure and test between the terminal and enclosure.

Ultimately avoiding any component having two connections to ground.

 

could you draw me a diagram on what your talking about

 

this is the diagram they gave me now on the dotted lines from the driver to the breakout board do i hook them all to gether or run jumpers

 

I'm afraid I'm a bit busy at the moment to do that but it's real simple mains ground to case, psu ground to case, driver ground to case etc etc and ox frame to case. Job done

 

So, there I am starting a new project, the demolition and rebuild of a National Guard Readiness Center. Meanwhile, on my own time, I'm looking into suppliers of Garolite (XX phenolic sheet) so I can give my OX a workout.
My electricians demoed the existing electrical panels and this was inside one of the larger panels. Is it garolite or phenolic sheet? The piece was 24.5" x 48" and measures exactly .2500" thick. I cut 8 inches off one end to make sure it wasn't particle board or Masonite. I don't believe it is as it is too hard and didn't
de-laminate when I took a vise-grips to the corner, it kind of shattered a bit. The first picture is of the edge that I cut with a circular saw. The last picture is where I used a pliers to break a piece off the corner.
I've never seen phenolic sheet or Garolite so I'm not sure if that is what this is. If it is then that's just awesome! If not, well I'm still on-site and I have a large dumpster. Can anyone tell me if I hit the jackpot please.

Josh

 

OKY FELLOR THIS IS THE HARD PART FOR ME can you guys check the wireing for me and see if you see any thang wrong lol go easy on me

 

https://www.google.com/search?q=gar...oTCJrBl7XTqccCFc9_kgodWKgOMg&biw=1920&bih=933

Garolite pictures

I think yours is phenolic. Garolite usually has a fabric in it.

Thurmond

 

An interesting read, thanks, not heard of bonding but if that is what its called then yes, doesnt have to be the same point, shortest point is fine if it passes the induction test.

Keep your mains earth cable larger diameter than your component grounds, current is going to flow toward earth and your grounds will stay at 0v

Oh and yes please dont confuse earthing grounding or bonding with
Neutral. Only talking about earth. Not a genious at this but I have taken apart some pro mills and have a father who is a great help with this kinda stuff, currently managing the electrical design and construction of a probe thats going to mercury for the European space agency tho hed probably call tell me theres some things I havent explained well, but this is how he helped me set mine up and how Ive seen it done on big mills.

 

Thanks Thurmond. Have you milled any of this? I did a Google search on milling/cutting paper phenolic and came up with very little.
Mark Carew, didn't you use some of this for gantry plates? If so, do you recall what type of end mill you used? I guess I should ask you if it looks like paper phenolic sheet.

Josh

 

Mark, Thank you Sir.

 

Hello Chris,

I recently discovered the Open Build site and am very intrigued with all that is possible here. I also saw the parts you offer on Ebay as well. You have so many comments on the quality of what you produce that I feel very confident if I should use your parts.

I was just wondering what machine you are using to produce these wonderfull parts. Also what software you use.

I have built 3 CNC router machines now and recently finished my "Big" machine. Constructed of 8020 extrusions it's a wonderfully accurate machine and has given me the ability to make parts of big proportions.

Now I would like to build a machine of smaller proportions and am looking here for the parts to do it. I am needing a smaller machine with a cutting area of 20x30 just to pick some numbers. Primary purpose is to machine plaques and projects using non ferrous metals. Protecting the wheels would be paramount I believe and I would use acme screws.

With all you've seen and done here is there a machine that's already been constructed that would be fit my needs? You've been exposed to so much here that I was hoping to get focused alot sooned than trying to sort out all the wonderful machines that has been built by others here on this site.

Regards,

Lee

 

We are working on a bigger Ox variant and would love your feed back on the design before we cut the first prototype.

Head on over this forum post to check it out!

http://www.openbuilds.com/threads/skateboard-shaping-machine.3058/

 

Hi Lee,

Yes, I have a chrisclub1 store on Ebay. It sounds like you have read some of my Ebay feedback

I have a Mori Seiki CNC and use 10+ different tools to make my gantry plates, router mounting kits, dust collector kits and custom parts. I have also made dozens of custom parts for people making variations and enhancements to the OX.

I am currently working with a builder in Austria to make a C-Beam version of the OX, starting with Rick 2.0's design and adding some enhancements. It should be done and tested in a week or two. So far, Rick's design looks pretty good.

I am not sure the smallest OX made, but you could go through the OX type CNCs listed here: http://www.openbuilds.com/forums/cnc-mills-routers.32/

Mark Carew recently released a C-Beam machine for small applications. You can see it here:
http://www.openbuilds.com/builds/c-beam™-machine-plate-maker.2020/

Best regards,

Chris Laidlaw

 

What kind of repeatable tolerances does a stock ox achieve?

 

oky guy i got cnc machine all wired up and now were do i go from here to test it plz help me lol

 

Yay!! Congrats.

Mind if I answer this one.

First things first. Set up your ports and pins for motors switches etc. once done set up your steps per unit. If not I suggest using an online calculator over the inbuilt calculator of control software.

Next set your motor tuning, I recommend for x and y 400mm/min 100 volocity. 200mm/min and 50 for the z. This will get you moving . Jog around the table get a feel for the jogging.

Next increase your mm/min for x by 100mm/min. Jog around, if it's ok. Repeat. Do this until the axis stals. Then back off by 30%. This is a rule of thumb optimal speed of the axis and you shouldn't have to change again.

Do the same for the y and z only with the z only increase by 30mm/min each time.

Now test your limit switches by manully switching and monitoring the LEDs of the control software diagnosis tab. If all are working correctly you can now home your machine. Once homed zero all the axis.

Now it's a good idea to check the axis are travelling the correct distance, jog away from the switch by say 100mm, then plunge down to the bed, and slowly step until by spinning the spindle by hand you can leave a mark on the bed. Now lift the z to a safe height, and zero the work coordinates, now type the axis Letter plus a dimension into the mdi eg x200 this will make the machine travel the dimension in the x direction. Now measure from the mark to the bit. It should corespond to the dimension. If so try again with larger dimensions until you have travelled the length of the axis. if you have a dti with a stand, bolt the dti to the bed, step the spindle holder into the dti so it compresses the dti by a few mm, twist the dti dial to zero it then zero that axis, type x with the largest dimension you know works ok into the mdi then once its done type the return move x0 into mdi. Now it should travel back to the dti and measure near 0. If it is within 0.3 mm chances are your steps per are correct.

If so Now re zero the dti. Step 1mm and then 1mm back, repeat this a few times if the results are consistently the same this is your backlash, enter the difference into your controller software backlash compensation for that axis and Repeat for all the axis.

If all is well Your now ready to try cutting. For your first cut I recommend a soft material, like foam or softwood with a 6mm bit. Set the toolpath depth of cut at 2mm federate of 1000mm/min and spindle at 10000rpm. Before you start the cycle set the feedrate override to 30%. Once the cycle has begun the bit will most likely be screaming, slowly up the fro until the screaming dies down, right up to the point it stops. If it sounds clunky you have gone to far, slow back to a whistle and you should be making chips not dust.

Enjoy.

 

First thang first thank you for helping me ...... Oky i did not get limit switches i will get them . the setting they gave me for my
Driver: DQ542MA is below . But it say for mach3 but i dont have mach3 3 can i use one of the free ones on this site for now . my breakout board is DB25. o i am useing windows xp.

 

oky thanks just down loaded it (mach3)

 

i cant get the machine to move lol

 

http://www.machsupport.com/videos/

All the help you need from the source!

 

guys i really need help here i have tryed every thang to get mach3 going cnc machine dosent repond at all
but looks like every thang is wired up rihgt and all lights come on may be my dip switches are set rong this is what they tell me to set them at sw1 on sw2 on sw3-off sw4 off sw5- on sw6, 7 off sw8-on

 

These are the dip switches on your drivers? Or elsewhere.

You need to initially determine that the bob is outputing steps, does your bob have an led to show PC signal state?

If so and its on. Aim to get a single driver powering a motor, once you figure one out its a lot easier to figure the rest.

Process I would go through is as follows:

1) check Mach 3 kernel speed, if set to an incompatible speed you won't get anywhere with it.
2) open ports and pins, check port number is correct.
3) pin out diagram of your bob, make sure the axis you have chosen to diagnose is set up with the correct port and pins. Active low doesn't play a part just yet.
4) is reset logic active? Set estop to an unused port and active low for now to stop it interfering. Just be aware of the location of your power off button instead.
5) using a multimeter, test the direction pin, you should see a voltage of 3-5v when changing direction of jog. Alternatively if you have an oscilloscope you can see the steps on the step pin as a series of blips.

I think you will find regardless of the dip switches of your drivers, the driver at any setting will move your motors so it sounds to me as your not getting any steps from the bob. Most likely you have a setting wrong in Mach 3.

 

what r BOB lol and thanks again

 

Bob = Breakout board, what one you using?

 

this chinness one lol

 

Okay so let's dignose x, you have Mach 3 set to x step/pulse to pin 2? And x direction to pin 3? Both the same port? Either 1 or two and it enabled? Most likely port 2

 

Also in open device manger and go into properties of your Parallel port and go to resources tab you should find the ports address. Make sure this corresponds to the port address that you have assigned to x ie port 2 on first tab when you open ports and pins

 

puls - is on pin 2 dir- is on pin 3