PHCad not processing a file.

[twehr]

Rich,

Post the file you are cutting that does inside cuts as individual strokes.

[baccus61]

Thanks Marco.
I have just made a couple of videos that are now uploading to YouTube and should be ready in a few hours. I will post the links when ready.
It will probably help others if they end up with the same problem I have and especially if it is their first laser build and wouldn't know whet happens if something goes astray.
I am trying to isolate every thing I can before I send it back for servicing as it is the 2nd one I have used and don't want to keep stuffing boards if there is something wrong at my end.
I may have noise as you suggest and it might be getting into the hardware and stuffing things up. I don't want to stuff any more up and as you said this one was tested before it left the factory but when I got it I still couldn't turn on and off the air assist. It has been the same with every board and so I think I might be doing something wrong.
I am trying to cover all bases before I do something drastic.

My work has finished now after 20 years and my employer doesn't have any more work for me and is hiring me out to whoever wants a Fitter and machinist or heavy Equipment Fitter. I won't have many days to myself over the next few weeks so it might be hard to get to the machine and test it.

I am sending my resume to people for a better alternative. So far I have had 5 job offers and that makes me feel a bit better but they all consist of doing 12 hour night shifts and I want to stay away from they if I can. All over $85K per annum. Not too shabby.

I am still in the process of setting up a test bench for the Yaskawa servo drives but that might be a few weeks away too before I get them turning. SO much information to remember. The servo manual is 1 inch thick.

Here's hoping for better times.
regards
Rich.

[baccus61]

Here are the 2 files I tried to cut in the videos.

A strange thing has happened in that I haven't been able to start the computer due to it being too hot in the shed and now that it is cooler I have been able to get it going and when cutting most of the lines making up the file are nearly all joined together .


They haven't got the 1-2mm separation they had earlier today as shown in the video.
The files still cut each individual line but at least they are joined or nearly joined.

Seems like the heat is getting to it as well.

I cut the original files this morning and it was about 25 deg C which should be OK for lasering but I still had the problem and it carried over to this afternoon.

here are the links to the new videos. I hope they turned out good enough to see what is going on.

http://www.youtube.com/watch?v=XrXl_sAtyg8

and just a small overview of what every thing looks like.

http://www.youtube.com/watch?v=L3pqASkeX3A

Rich.

[twehr]

Rich,

Thanks for posting the videos and files. I looked carefully at each and, after 35+ years of software development and debugging, and nearly 30 years of mechanical engineering, I may have an idea or two. Hopefully some of it will be useful.

Observations:

• 1. Aunty file looks normal to me.
  2. Aunty output - the gaps appear to be where the laser has stopped short of the end of the line segment. (All line segments - line between nodes - have to be treated by software as individual lines - has to do with sharp changes in direction. So each gap is where a line ends.)
  3. Aunty output - In the video, you say and I see that you have the overlap set to .05 mm. I believe the purpose of that setting is to tell the laser to stop short of the end of the line segment so as not to overlap a previous line. I have never needed to set this on any file I have ever run (current or older controller), so it may be that it is doing exactly as you tell it to - to stop short of the end of the line.
  4. Aunty output - The fact that it always comes back to the correct origin rules out skip or lost steps.
  5. Aunty output - The fact that it does not trace the exact same path says there is "play" somewhere in the system.
  6. Andrew file also looks normal to me.
  7. Andrew output - Still stopping short of the end of each line segment, consistent with other file. (More noticeable on the slower output - you can actually see the laser turn off short of end.)
  8. Andrew output - Regardless of the shortened lines, the vertical placement is not consistent - tops of letters are overlapping previously lased portions of the same letter. This indicates play in the vertical axis - horizontal appears to be OK.
  9. Squares output - all the mismatch of line segment joins (nodes) is in the vertical axis.
  10. Squares output - you can see the path of the red dot after the laser turns off - it continues on (to the presumed end of the line segment). It then appears to change direction and briefly go 180 degrees (opposite direction) of the NEXT line segment before again reversing to lase the next line segment. This is similar to the motion that the system makes when engraving - backing off of the start point far enough that it has time to accelerate to the correct speed before turning the laser on for the next scan line. Also similar to an anti-backlash move in conventional CNC.
  11. Squares output - At the very end, (7:59 or 8:00 into the clip), the laser completes the cut exactly where it started it, but then the head moves back to the right slightly. Don't know if that is springiness in the system or hitting your x 0 limit and resting - I suspect it is springiness.
  12. All three original art pieces seem to be very small (Andrew is 4mm wide x 1.5 mm high).

Thoughts -

• 1. Set the overlap to 0.
  2. Most of your play seems to be in the Y axis - the machine mass is much greater in Y than in X. Even with large belts, you can get a pretty good inertia going.
  3. Try a much larger test - something with 20+ mm line segments at slow speeds. See if the gaps and overlaps are the same or proportionately larger or smaller.
  4. Springiness in system can also be the cause of your misaligned output on scanning.
  5. To handle the end-of-line piece, you could set the laser delay (Close Delay in Cut Advance Parameters) to a small amount to delay turning the laser off at the end of a cut. (Never tried, but might help.)

Other than the possible overlap setting, I honestly do not believe this is a software issue. As for the controller itself, I doubt that it is a "faulty" device. I suspect that trying anther v2.x controller will behave the same.

I do believe the issues are directly related to the size of your machine. It is very large - lots of mass in both directions, but more in the Y. Getting it going and stopping it take time. It may be that fine movements (vectors) at very small sizes is not well suited to your mechanical setup. To work at these sizes, it may be that you would have to go to ball screws (expensive at that size). It is possible that larger motors with higher holding power may help with the inertia, but if inertia is causing slight belt stretch/contraction, then starting/stopping power may not help much. Don't know what size (in/oz) you are running but suspect you need something in the 400-500 in/oz range or higher.

Wish I had a magic bullet for you, but the year is young and I have already run out of my supply.

Keep us informed as to your progress (or any new developments).

[twehr]

A strange thing has happened in that I haven't been able to start the computer due to it being too hot in the shed and now that it is cooler I have been able to get it going and when cutting most of the lines making up the file are nearly all joined together .

If you really have a heat issue with the computer, it is even more likely that you have a heat issue with the controller. Make sure your enclosure is well ventilated and fan cooled, if possible.

[baccus61]

First off, thanks for the lengthy description Tim. I know it takes ages to type all this stuff up.

Now.......

I went through the computer and unplugged the disk drive control cable and replugged it in and I don't seem to be having the resetting problem I had before. I then went through and did the same to all the other computer cables to make sure.

I sat down and went through all the settings in PHCad to see what I could do to change things and found my problem with vector cutting.

In the Download Settings box is a check box for " Lessen Laser Power at Start ". I unchecked that and now the laser follows a continuous path around all vectors.

The problem I think is in the translation from Chinese to English. They are very close to what the language defines as a particular word but sometimes it just isn't close enough and means an entirely different thing. Now I would take this setting to be " Lessen Laser Power at Start OF VECTOR LINE ".

I also earthed the control board a bit better and checked the table was earthed properly and it was.

I am now going back out there and I will rewire it again for the last time just to make things look better. I notice that the manufacturers place all their wires together in cable track so it can't hurt to do this. I will just cable tie them together except for the AC power wires.
I have ferrite cores around the signal wires to try and keep the signal clean but I think it probably won't make any difference but I will leave them there for a bit of security.

I have had the laser head flying all over the place with the older Linkmotion software and also hardware option and never had any problems ( It just wouldn't do engraving the right size). I could push it so the table was almost falling apart and it was jumping all over the place (and it weighs about 200Kgs). I don't think the table size is an issue.

There is only so many times one can re-tighten the grub screws on all the pulleys and re-tension the belt. I know it seems like it is a mechanical fault with the engraving but I will be damned if I can find it. EVERYTHING is tight. I have even checked to see if the laser tube itself moves while engraving but the speeds I am going it doesn't cause any vibration to the table at all. 1 mirror assemble mount on the gantry is a little bit on the light side but it is hard to move it by hand and it only moves a few thou which wouldn't cause a 1mm distance between lines. I checked while moving it and it only causes about 10 thou deviation. The only force on that is in the Y direction so it would only manifest itself in the Y direction in the engraving, not the X and being at 45 degrees it probably would be a diagonal error anyway.

After the rebuild I have removed about 0.5 Kgs of plate from the gantry so it is actually lighter than it was before and the belt on the X axis is twice the thickness and width. Taking into account the THK rail slides added as well. The Y axis motor drive is twice the width and also a thicker tooth profile than before so slip isn't too much of an issue with that axis.

I'm getting there slowly.......but surely. Testing will continue................................................!!!!!

All the help is much appreciated.
Warm regards
Rich.

[baccus61]

I had another crack at the laser today and thought I would try the engraving and cutting processing on 1 file and it didn't come out too good at all.
I drew a simple vector heart and then placed some words inside and converted them to a bitmap and sent it to PHCad.

I checked the 2 boxes and arranged the different parts so it will engrave first then cut 2nd and sent it on its way.

The engraving lost steps 1/2 way through (set at 60mm/s ) and finished, and then when it came time to cut, it distorted the heart by squashing it sideways but the head came back to the start point about the same distance the lost steps were. The cutting was warped. I had a small hole to cut for a thread and this came out oblong shaped (oval) at about a 45 deg angle. It seems like it wasn't processed properly.

Tomorrow I will grind clean a piece of metal on the shed frame and attach a wire to it and ground the whole table and DSP board as well.

I haven't had this problem before because with this DSP as I have never tried to do the two processes at the same time with the PHCad . It's just one of the many in the long line of them.

I'm not finished testing it yet and the servo drives are on hold until I get my 60 hour per week job sorted out. Funny how the rest of the world are cutting back their working hours and we here in Aus are increasing them. Supply and demand I suppose. I will be applying for a job with Atlas Copco drilling services as their working hours are 7on and 7off 12 hour shifts which are a bit better than what I am currently on.

regards
Rich.

[baccus61]

I disconnected the 12 volt supply from the Computer power supply and replaced it with a Switch mode power supply and it has made a difference to the running of it.

I can engrave at 60mm/s without the 1mm offset

BUT

I can't go over 60mm/s as the steppers lose steps and the engraving comes out with a 5mm offset. This is a constant size at any speed over 60mm/s.

I still haven't tried engraving and cutting in the same file yet and I will after lunch today but at the moment it looks like a power problem.

I might even hook another computer up to it and try that as the computer I have in it seems to be getting a bit quirky.

Every step is a step in the right direction. At least I have seen a difference in what I have done this time.

Rich.

*** UPDATE ***

The computer hard drive crashed last night so that probably confirms that I have a bad computer so I've ordered another new moterboard and chip with cheaper DDR3 RAM and I will replace the offending HDD.
I hope this will make an improvement. Time will tell.
Rich.

[baccus61]

WELLLLLL,

I have updated the computer and reloaded all the programs back in etc etc etc. (I have ordered a solid state drive for it for some stability in the heat of the shed)
back to square 1 again.

I ran the programs again and still got the same speeds and I noticed that the X axis motor was cold.
NOW, typically, stepper motors run at around 60 - 80 deg C so I should have burnt my little scratchers on it so I realised that I didn't have enough amps going through the motors. There is no label on the stepper so I don't know how many amps I should use so I got a heap of resistors and went-a-changing the Gecko amp rating.
After about 4 different ones I have settled on 3.5 amps which makes the motor pretty hot to touch so it should be just right.
My speed then increased from 80mm/s to 300mm/s and just started to lose steps at about 320mm/s.
I still have the 1mm offset with engraving though and I think I will have to live with it. I can actually use it now but only in Unilateralism. I'm pretty much back at where I was 2 years ago with the software only Linkmotion but with a lot more functional piece of hardware and some clever software that does Vector cutting and bitmaps in the same job.
Speaking of which, I need to try that again as it wasn't so good last time I did it.

I'm pretty much back on track again for a while.

One other thing. Has anyone had any problems with the red diode pointer lenses cracking and being unusable. I have 3 gone to the dark side in the last month. I wish I could make them or buy a replacement somewhere. I might be getting some reflection from the 100 watt laser through the beam combiner and heating them up too much.

Rich.

[Russ]

Hi All,
Think I could be of some help here, after an afternoon of fun I was double checking stepper motor wiring and realised the "Typical minimum connection" schematic is just plain wrong..
Two +5v's can't make 5v, but it will have a go and drive you up the wall by nearly working properly..
If your common is +5v, Step and Dir pulses need to be at 0v or Gnd or -5v can't remember how the Chinese have marked it..
0v common +5v Step and Dir pulses is my normal way
Hope this helps all with this issue, if anyone can tell me how when and where I can get any sort of output to trigger Air and Vac it would be great, fiddled with "if blowing" but outputs remain high (5v ish)

Thanks to all posters, forum's very handy

x

[baccus61]

Thanks Russ.
I might have a go at that.
Strange how a lot of people have trouble with the air assist buy the manufacturers don't seem to have any problems when they build them. That's a conundrum I haven't overcome yet.

The past 2 weekends haven't been good to me as the laser is tripping out through earth leakage for some strange reason. Every time I leave it for a week it stuffs up when I go back to it.
I pulled all the positive wires out and replugged them and the problem went away for the day but the following day it tripped out again. I don't think it likes to be out in the cold on it's own and It seems to want me to be with it 24/7.

I've ordered a 48 volt power supply and will rewire it again and see how it all goes this time. I can do this in my sleep now.
Rich.

[baccus61]

Received the 48 volt power supply a week ago and wired it in today. The switches leading into the table were the culpret of the earth leakage so I just hard wired the power to the terminal strip to bypass eveything.
I did some simple tests to see if the table worked and it seemed fine after the initial problem of the computer monitor cable getting caught in the drive belt and having a splatter of solder drop into the HMI cable and short it out. I removed the cable and cleaned out the solder from the connector and every thing is back up and running .

Test number 1 was a simple square and circle and a wavey line.

I tried cutting this at 100mm/s and it went good. So far so good.

Then I set it to 200mm/s and it was fine with no loss of steps. The old power supply would have stalled at this speed. (It's a torroidal transformer that cost me $110 and is 8 amps @ 36 Volt)

I tried 400mm/sec and still ok.! This is GOOD!

I bumped it up to 600mm/sec and it cut but lost a couple of steps in the Y direction. This is a heavy gantry so that is also good. (I'm on a winner here after 1 1/2 years)

I loaded in a bitmap picture of a small girl and set the engraving speed to 400mm/sec and the motor stalled and squeeled.

I dropped the speed to 200mm/s and the X axis motor worked but lost steps all over the place.

I dropped again to 100mm/s and it engraved really good. My speed is now set at 150mm/s which I am relatively happy with. I will have to change some velocity settings to see if I can improve on this. I think I could probably push this out to 200mm/s in the end. It should be 1000 for this fairly heavy lens assembly but I will live with that.

I changed the X direction to "X-Swing". I haven't been able to use this setting due to the engraving having a 1mm offset which has been with me the whole time from way back when I built the table the first time and had to use the "Unilateralism" setting.

The 1mm offset is gone. (much clapping and rattling of tankards)

It looks like the power supply has been the problem all along. This is a simple set up of 1 torroid, 1 full wave bridge rectifyer and 1 really huge capacitor. ( The Cap might have been the problem)

I now have a 48 volt switch mode power supply for the grand total of $38. I feel cheated!

I hope I can now say that this saga is finally over and I can put the DSP to bed. I just need to change out the switches on the table and I am finally back to square 1.
Who would have thought, Eh!
Signing off for now
Rich "the winner" McMahon

[twehr]

Received the 48 volt power supply a week ago and wired it in today. The switches leading into the table were the culpret of the earth leakage so I just hard wired the power to the terminal strip to bypass eveything.
I did some simple tests to see if the table worked and it seemed fine after the initial problem of the computer monitor cable getting caught in the drive belt and having a splatter of solder drop into the HMI cable and short it out. I removed the cable and cleaned out the solder from the connector and every thing is back up and running .

I hope I can now say that this saga is finally over and I can put the DSP to bed. I just need to change out the switches on the table and I am finally back to square 1.
Who would have thought, Eh!

It's about time, Rich.

Like I always say, "the answer seems easy and obvious, once you know what it is."

[baccus61]

Short lived success.
I went into the shed tonight to do some more work and guess what????? The offset is back!!!!
The LCD screen is also playing up as it has done since new but it is doing it more frequently now and the menu items get scrambled and unreadable and when I process a file the screen goes blank.
I have disconnected all the cables and cleaned the terminals but still get the same problem.

I think I will order another DSP from Marco and try that and see if there is any difference and then send him the old one for testing. There isn't any thing else I can try. I need a new DSP for the other 30 watt RF laser anyway and I can still use the 100 watter for a while until the new board gets here. I can't take it out until I get a replacement due to getting a fair bit of work lately. (about 1 job every 2 days. )

Does any one have any info on why internal circles don't join up back to the start. The end of the line will stop about 1-2mm next to the start of the line on the RH side of it so the piece won't drop out. The outside seems to cut properly and I tried changing the circle settings but it didn't make any difference.
So many intermittent faults!

Rich.

[baccus61]

Well, I do jump to conclusions way too easily!
I went out to the shed yesterday and had another good look at the way the laser was working and found 2 loose screws on the secondary toothed pulley that drives the main belt for the laser head. 1 was stripped and the other was very loose so I tightened them up with a dob of Loctite on them this time just for good measure. I've had the tube of Loctite since 1988 and it still works fine. Good stuff that! I hope I won't need to take them off anytime soon as it is the old 601 super thread locker. 300 deg will break the bond or a very good gear puller will pull it off.
Now it works like it did before but I still get the LCD screen going blank or reverting back to Chinese language.
Rich.