Thread: CNC Gantry Router #A

Hi Rod, you should be able to use Greg's opto board with your BOB, I would have to have a look at the schematic but it shouldn't take much altering if any.

I had the same problems and fixed it by using the motor supply voltage for my limits (in my case 30V) and a little opto board. I got lazy and used the perforated hole type board instead of making a board. My home made drives are noisy enough to kill the shed radio when they are on but I don't get any limit/estop trips any more.

The higher the voltage the better the noise immunity, if you can use 12 volts that should fix the problems.

Oh yeah, forgot to mention my limit switch cabling is unshielded and runs alongside the motor cabling for almost the whole distance.

Russell.

Thanks for all the help - it is really appreciated and will also give some insight for others to follow.

I should have been clearer about my posts. My main goal is to get the machine cutting at the moment. I have been building on and off for seven months and want to see it work. I don't run a machine until all the guards and frilly bits are fitted otherwsie they never get finished.

The electronics is another issue and something I struggle with constantly. Big hands, poor eyesight and lack of knowledge makes it difficult and frustrating. I have put in four eight hour sessions at night with my head inside that box fiddling with the electronics. I am at a stage where I need to eliminate some of the variables and the SS is the first to go. The way I have it hooked up it is easy to connect it back in and have another go down the track but I will not be in a hurry to do that.

The VFD was not causing any problems with the SS but it is with the parallel port connection. The limits were also not causing any problems with the SS as Greg's board was able to be used and works at 12 volts. Why I don't like the SS is that if it disconnects you have to shut down Mach3, disconnect the USB and then fire it up again - result would be all references lost in Mach3 and job ruined. If the parallel port triggers then you simply hit the reset button and can continue with the job - fail safe.

I have taken on board all the suggestions and this is my plan of attack.

Remove all the high voltage from the electronics enclosure and install it in another switchboard on the machine. Greg has very kindly offered to make another 12 volt board for the limits that I can connect to the parallel port and I know this works so that will overcome the false triggering. I have only ground one end of the shield for the VFD/Spindle so will ground the motor end.

Let me know if I missed anything there.

So all this is not going to be an overnight fix but I think it is better to start again. Will keep you posted on the progress. If I make this through with a full head of hair and only a few barked knuckles I will be doing well.

Hi Rod

I believe moving the noisy stuff into another housing will certainly help...But if you do still have problems may i suggest also installing a filter on the supply side of the vfd...

Many moons ago when i worked for a company which built cnc Laser cutting machines,they decided to install vfds on their transfer tables as it would allow them to ramp up and down the speed as required in both directions.(instead of DOL fwd/rev contactors).....anyhoo while commissioning the first install of the new vfd (SEW brand) i noticed everytime i initiated a transfer via the console the screen would go blank...while transfering..after a lot of hair loss ;-) which im sure your now familair with...we added a 3 phase filer (SEW brand whicn mounted under the drive) and all was well....A common brand of filter that i have used in the past is Westek...check out link
http://www.westek.com.au/index.html
Good Luck
Frank

I am smiling and laughing at myself at the same time.

When I was struggling with the smoothstepper many posts ago Greg mentioned about fluros triggering problems.

Well I have been working at night on this and I have a portable light with not one but three fluros and to fall into the trap a bit deeper this has been connected to the same power lead as the computer and the machine. Something as simple as that looks like it has been my problem all the time. The hint was there and if I had slowed down and thought about it I would have been running with the SS way back. Do I feel like a knucklehead - you bet ya

So I am running the CNC4PC board in parallel mode and have set the debounce in Mach3 to 1000 and been running the machine for a couple of hours, turning on and off the VFD, vacuum and air pump with not even one false trigger.

Thanks again to all for your suggestions. This forum is great for getting past these types of problems.

Been running the machine for about eight hours and not one false trigger. I think that is as good a test for reliabilty that I need to do. It has been a roller coaster ride at the end but pleased with the final result.

Reclaimed the table top - read cleaned all the tools and materials off it.

I also made the touchplate and hard wired it into the machine so it is 100% mechanically and electrically complete now and I will dial the table in tomorrow and take it for a test drive.

If all goes well I will post some photos and maybe a video of it in action. I am going out tomorrow so time might be tight to get it all done but there will be something this week to show the air spindle in action. Looking forward to that.

My head is already thinking about the mill I am going to CNC so it doesn't stop here.

Rod,
I have been following all of your trials and tribulations with great interest and I must say a degree of trebitation in that all of my electrickery stuff is still ahead of me. I did get into the workshop for a bit yesterday and am working on my Y axis, so am starting to see some form coming out of the piles of components.

Glad to see that your tabletop has been cleared.

Cheers,

Alan

Hi Alan,
I would not let my experience influence your thinking as I got too focused on the problem and had I stood back and seen the light I would have been running a lot earlier.

Some pictures to show you how it ended up. Covers installed over the linear bearings, emergency stop installed, perspex covers on all the pulleys, air pump with outlet at the spindle and touchplate ready for action.

Hopefully I will get home early enough to dial the table in and give it a run.

Good thing now and I won't mention that other thing..

Be good to see what you think of the spindle when it has cut a bit.

Thanks Bob,
Consistency is good and when it comes to electrickery I am certainly consistent.

Got the table dialed in but didn't have enough time to give it a test run. Maybe tomorrow night.

I will give feedback on the spindle as I know there is a bit of interest with them.

A very hastily put together video of Morph's first run.
The spindle noise is an improvment on the router but there is still a lot of cutter noise at that speed and feed. I didn't take much notice of the setting but it was around 3m/min and I did crank it up a bit as it was handling it well. I think I could crank it up more when I get used to the machine.
Anyway for a first run it is doing everything I wanted it to do

Amazing stuff as always.
It's great to see the progress from a bunch of bits and pieces to a finished, almost living machine (I'm sure I heard it bark...)

And much better watching than anything that's on TV at the moment!

Very Nice

Does a beaut job.....

Rod,
Great movie after all your trials and tribulations it's great to see the beast dance like a graceful dancer.

Cheers
Steve

Great movie Rod. Great machine. Congratulations on Morphy's first steps.

What hp is that spindle?

Greg