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Sorry should have stated that, all limits were checked manually and all seem to correspond to the correct input. Soft limits were turned off during the troubleshooting process.Quote:
Originally Posted by Chaz
Jazz, system jogs great, homes correctly on all three axises. I tried MDI commands and get the message "Move off Limit before MDI command". Whats puzzling to me is that Mach says this even with all limits turned off.
thanks for the quick replies
Actually thinking about it I've had this before but can't remember what caused it.! . . . Got feeling it's something silly and obvious like a setting but can't for the life of me remember what.? . . . . . Nearly bed time so I''l sleep on it and get back to you.
I took a little break from the machine and came back to it. Ended up being a debounce issue, it looks like my cable grounding wasnt as good as I thought. I doubled the debounce to 8ms and the MDI and Gcode both ran....Quote:
Originally Posted by JAZZCNC
Pretty darn cool to see it run on its own, I am so close to cutting...
Here is a pic of the CSMIO-IPA Config window for setting debounce for anyone in a similar situation.
Attachment 20304
Not good idea to use de-bounce because it affects all the inputs and slows down re-action time. Find the problem and fix asap, esp if using servos because want any inputs to re-act fast.Quote:
Originally Posted by Scott Damman
Edit: Actually I see you only have set to 2 which isn't so bad thought you'd set it to 8 which would have been 32ms.
Jazz, good point either way, I think I will dig into the shielding a bit more on all of the control wiring. Would like to get it back to 4ms. Like you said fix with hardware, totally agree.Quote:
Originally Posted by JAZZCNC
thanks again, more to come
Have you Earthed the Frame.? Common cause of troubles like this.Quote:
Originally Posted by Scott Damman
No I hadnt, I added a separate ground for the frame and grounded each part of the machine, i.e. Gantry and Z. Thanks for the suggestion.Quote:
Originally Posted by JAZZCNC
I learned some hard lessons last night while continuing to tune the servos.
1st, make 400% sure that the ballscrew mid-supports can not get hung up on a sudden change of direction.
Attachment 20317Attachment 20318
This bent back pretty easily but I will need to make some modifications to make sure it cant happen again. Basically the machine stopped before the support flipped and on change of direction it caught on the ballnut mount. No other damage observed which is good.
2nd, and this is the big one, when butting linear rail together remove the lead in on each rail. I had known this was the case but being that I got the rails for cheap and not having a way to accurately grind the rails I chose to try it.... bad choice.
Attachment 20319Attachment 20320Attachment 20321Attachment 20322Attachment 20323
What the pictures show (or what I assume happened), as the block went past the joint a ball dropped into the joint, caused alot of extra force and blew the end of the block off. At lower speeds it seems to be fine, but I was running past it at ~1000 ipm. I think the block counldnt handle it I was able to stop it before the other 2 blocks hit the joint. I have 4 extra blocks that came with the used rails so I can put it back together for now but I need to make a plan for future.
I think my options are
1 - remove rails and have them ground and put back together - this is a no go as the cost would be more than just buying Hiwin rails
2 - buy Hiwin rails and blocks - definitely the best option but costly
3 - try to fill the groove/lead in
- Im thinking of trying this method, couple options, epoxy, babbitt, other options?
- I think I just need to keep the balls from dropping in there, I think there shouldnt be too much stress on the fill otherwise.
4 - just use the 8ft of full length rail for now???
Any thoughts are appreciated...
Ouch.!! . . . Bad luck. That's difference between Servo and steppers. They take no prisoners! . . . Stepper would have stalled before bending that bracket or possibly ripping the bearing end cap apart.!
1st Choice is no brainer new Hi-win rails.
2nd Choice new Hi-win Rails
3nd Short term Choice fill with Metal Epoxy. Think it's called JB Weld in states.
No other choices IMO.!
Short term I have moved the entire machine to the other side of the joint and moved my X home switch. Gives me 6.5 feet in the x and 5.5 feet in on the Y and gets me going with making parts. I have ordered machinable epoxy to do a pour to try to fill the joint. Long term after a few paying jobs, probably going to order some new full length rails. This will unfortunately require some modifications to the machine as the rail height will be different.Quote:
Originally Posted by JAZZCNC
Im still waiting on my spindle cooling fan adapter so I cant cut anything yet. So I put a sharpie in the spindle and made a drawing. Pretty geeked that it actually made something, even just a drawing.
Attachment 20335
https://youtu.be/J3Nyo5k5jGg
While still waiting on the fan adapter so I can cut with the machine, I decided to draw up a dust collection adapter mold to lay up fiberglass in. Video shows the machine running this code.
Attachment 20339
https://youtu.be/KvlEG_NkDNg
I put the X and Y to 1000ipm as 2000ipm scared me and while I am learning about this machine I wanted to be a little safer.
I also have a question about what a ballscrew/ballnut should sound like. I have never been up close to a ballscrew before so I wonder if these sounds are normal. The sound I am referring to sound like bearings circulating through the ballnut but just doesnt sound real smooth... Sorry pretty hard to tell on the video I guess but if anyone has insight please let me know.
https://youtu.be/64T4WCVUdHk
I have seen dust collection but your blasted me from my chair :encouragement: If thats not OTT, i dont know what is. May be what once i have seen the whole spindle in the dust tract.
I helped someone with a kneemill yesterday. Not a new machine but still in good condition. I could also hear balls recirculating when we were moving the Y Axis. I *think* its normal but wouldnt mind the guidance from those more experienced on the forum.Quote:
Originally Posted by Scott Damman
My 1605 screws make a Shhhhhh noise when doing rapids, they get a bit quieter after a grease.
Looking good Scott coming along nicely.
The bearing noise is quite normal for that class of bearing at those high speeds. It won't be just the ballnut your hearing either, the linear bearings will make noise also.
Boyan, thanks I think it might be a little much and also Im not real sure how it will work but I run 6inch to all my machines and have a 10hp cyclone dust collection system so I thought it would be better to have 2 4 inch tubes down to the bit rather than just one 6 inch. I will make an update on how it works once its all hooked up and the dust shoe is made/installed.Quote:
Originally Posted by Boyan Silyavski
Thanks for the comments on the ballscrew/nut the sound just didnt sound great but like I said I havent ever been close up to a machine. Of course once it is cutting those sounds cant be heard.
So I decided to make a temporary spindle cooling fan adapter and get this thing cutting. So the first thing I wanted/needed to make is the dust collection adapter mold.
Attachment 20377
Heres the machine cutting for the first time.
https://youtu.be/H3z2QBAujfE
https://youtu.be/pZp9UeCNjcE
Turned out pretty good for the first cuts, here is a final picture and the first 1/2 of the dust collection adapter laid up in fiberglass.
Attachment 20378
Attachment 20379
I learned a few things on my machine, first one was not to difficult, I needed a better tune on the Z axis. I think you can see in the movie that the Z actually moved up and down slightly through its pass, for this part it didnt really matter so I let it run and played with the tuning a bunch more and I think I get it pretty good.
The other thing is I was making ellipses instead of circles. Again this part didnt matter that much so I let it run to look into it after. So after confirming gantry to X squareness I started looking into what else it could be.
Heres what I found and looking for a little help on this, I also want to say that I really appreciate all the help the experts on this forum give and I hope this build helps others with theirs..
I put the machine on a 10 inch X movement back and forth at a moderate speed, while watching the gantry I could see a noticeable racking of the gantry. Upon stopping, the gantry comes back to square. It looks like to me that X axis slave motor/ballscrew is noticeably slower at starting. I tried to use the motor delay setting in Mach, I moved the milliseconds up (delaying the master motor since the slave seemed slower) but I could not see a noticeable change. So for all of the experts out there, is the motor delay something I should be adjusting? Or is there something else I should look into? I have confirmed all the settings in Mach on both motors are the same. I also confirmed the settings in the servo drives are the same. Any thoughts are appreciated.
Thanks
Scott
EDIT
I just looked closer at the delay, I had assumed that it was a signal delay, but as the manual says (which I should have looked at first) the motor delay is for delaying the enable signal for that output. So now I really dont know what to do.
The reason I say the slave axis seems delayed is the gantry racks as if the master motor is the only one driving it. I thought maybe the slave motor was/is not running but the fact that the gantry gets to square when it stops I think tells me the slave servo is running (resolver is bringing the system back to correct position). The servo drives output for speed match when running as well. Hope there is a good way to adjust for this delay?
Make sure both servos have exactly the same settings in the servo drives themselves. I do that by copy-paste-upload from one servo to the other in the servo tuning program. So i am 100% sure they work the same. Do so in mach 3 in motor tuning tab and make sure to hit "apply". Close. go out of mach 3, then do check again the result. Then make sure the direction of motors is set right before you rip your gantry.
Then test.Now all must work normal
About the dust, i see. You are right that dust extraction better not be choked down. I assume you will fit a kind of shoe there. Or you will extract only the fine dust not to float around in the air? I use sometimes my dust shoe only like that, without the brush attachment. Chips stay on table but no fine dust in the air.
May sound obvious but if you are using pulleys are they the same size.?
If this was Step/Dir setup I'd say the Step pulse was on wrong edge but with Analog IP-A then can't happen.
Does it look like it's running out over time while cutting or is it off straight away.? . . . . It could easily be electrical noise inducing voltage on the signal lines.
This would have the same affect has being told to move fractions of inch more than should. The encoders will always bring it back to zero when homing so very difficult to see.
Does it do it without Spindle Running.?
Do you have any Line filters on the Drives or VFD.? . . . If not fit some because Servo's, esp Analog don't tolerate noise in power line very well.!
Boyan, I went through all the parameters manually as the drives from BST Automation dont have a computer hookup. But I was able to confirm that all parameters are the same in the drives.Quote:
Originally Posted by Boyan Silyavski
Thank you for the thoughtsQuote:
JAZZCNC
Re: First Build 5 x 12 Steel Frame CNC router
May sound obvious but if you are using pulleys are they the same size.?
If this was Step/Dir setup I'd say the Step pulse was on wrong edge but with Analog IP-A then can't happen.
Does it look like it's running out over time while cutting or is it off straight away.? . . . . It could easily be electrical noise inducing voltage on the signal lines.
This would have the same affect has being told to move fractions of inch more than should. The encoders will always bring it back to zero when homing so very difficult to see.
Does it do it without Spindle Running.?
Do you have any Line filters on the Drives or VFD.? . . . If not fit some because Servo's, esp Analog don't tolerate noise in power line very well.!
Both sets of pulleys and belts are the same and came from the same supplier.
It is more of a delay to start, i.e. the master motor starts moving and the slave starts up just slightly after (which racks the gantry). When it comes to a stop the master stop slightly before the slave bringing it back into square.
Happens whether the spindle is on or off.
One thing to note the cables are 1meter longer to that motor than the master motor. I wouldnt think that should cause this but maybe?
I think to your point it is likely noise, I found yesterday while cutting some other parts that my Y is undershooting its commanded position. I was cutting a part that was supposed to be 8 inches in Y and it is 7.85inch. When I run the Y without the spindle on and a dial indication its within 0.001inch... So I am going to have to dig into the noise.
When you say line filters on the VFD's you are talking input line filters correct? I will see if I can come up with some input line filters. Also want to dig into the grounding more and confirm that everything is hooked up correctly. I have everything grounded back to a single point in the cabinet and then that run to our homes earth ground. I am thinking of driving a separate ground rod for the machine to give it a shorter path to ground, good idea? The spindle is run with triple shielded continuous flex VFD cable, the cable shield is connected to the chassis of the VFD using a VFD cable connector, i.e. the shield is connected 360 deg to the chassis of the VFD. The VFD is then grounded back to the single point ground in the cabinet. Open to help on this!
Made some progress on the dust collection adapter first picture is the first half out of the mold and the second is the second half laid up in the mold.
Attachment 20388
Attachment 20389
Also worked on a support arm for dust collection tube. It bit overkill but it was fun to make...
Attachment 20386
Attachment 20387
Again another obvious suggestion but got to be said to eliminate. Not got loose Pulley.?Quote:
Originally Posted by Scott Damman
Yes Input line Filters.Quote:
Originally Posted by Scott Damman
Did you Earth the Frame.?
Re: Separate ground rod then I'd say not because want to use the same ground that mains supply does so don't introduce ground loops. However I'm not expert on this and don't know the differences between American and UK electrics other than frequency.
I appreciate all of the "obvious" questions as it is easy to overlook items when troubleshooting... Yes confirmed no loose pulleys, I also have been watching the actual belts on the servos on X (hard to watch both of course) but it looks like the master is moving before the slave. I plan to swap cables to those motors and then swap drives and find where the issue follows. I can then hopefully pinpoint, cables, drive, motor being the culprit. (or still noise)Quote:
Originally Posted by JAZZCNC
Frame grounded and I have a ground going to the gantry and to the Z axis to make sure each part is grounded in the frame.
So the separate ground would need to be bonded back to the ground ref in our house (as I believe this is code). My thinking here would be that this ground rod would give a much shorter path to earth for the Hf noise. Not sure it would make a difference or not just something I was thinking of trying.
One question I have is about running cables in the same drag chain, I had assumed that having good shielded cables that I could run all of the cables together in the same chain. Is this a No/No?
I have been looking into line filters to try to get some ordered for the servo drives and the VFD for the spindle.
Not good idea unless you know they are isolated. It's little things like this that can easily introduce ground loops. I would remove the Gantry and Z axis earths and check again.Quote:
Originally Posted by Scott Damman
Also don't Earth the PC chassis to the Star point. This can cause all sorts of strange happenings. The PC PSU will have it's own path back to earth so adding another affectively creates G-loop.!
If all is correct regards Grounding etc and with good wiring practices then shouldn't be problem. I do this all the time and don't have any issues.Quote:
Originally Posted by Scott Damman
However it's always good idea to keep some seperation of high power/frequency cables like VFD or Mains voltage in respect Signal wires. Esp if the wire runs are long which guess may be on your machine.
This is a major one - spent weeks debugging a plasma table build just because i grounded the PC case to the table, disconnect it and instant fix!Quote:
Originally Posted by JAZZCNC
Have you ever check your belts(tooth size, tension)?Quote:
Originally Posted by Scott Damman
Also are your motors and ballscrews bases tight enough?
Gantry have to be grounded to frame on Plasma otherwise you can weld the Hiwin balls together :hysterical: I believe that is correct to connect gantry to machine body whatever the machine, to avoid that bearing fault, it had its own name, but i forgot it...
Yes to the machine frame but not back to the Star point. Only one Earth cable should go back to this point.! Scott is runnig separate cables back to the Star point which Can/does create Earth loop.!Quote:
Originally Posted by Boyan Silyavski