MechMate CNC Router Forum

MechMate CNC Router Forum (http://www.mechmate.com/forums/index.php)
-   MechMates already cutting (http://www.mechmate.com/forums/forumdisplay.php?f=78)
-   -   Experimenting with options for vacuum clamping - Taibao, Taiwan (http://www.mechmate.com/forums/showthread.php?t=849)

Alan_c Thu 18 September 2008 11:36

Hey hey hey! what's the secret, lets see some pics as proof :D I am interested to see the completed machine and how that electrical panel looks now that its working.

Greg J Thu 18 September 2008 20:53

Congrats David.

Pictures Please. :)

It is a beautiful design, don't you think. The college of MechMate. :cool:

liaoh75 Thu 18 September 2008 22:41

I'll post some pics over the Weekend. It's still not 100% complete. It is just "usable" at this stage for testing. Push buttons and limit stuff are not hooked up yet. I am going to be mounting the computer and monitor in a console attached to the machine itself. This will come later. This software and spindle stuff has my full undivided attention at the moment.

If you guys really want to see some of the amazing rubbish I've been cutting, I don't mind posting the pics but it's nothing to write home about.

javeria Fri 19 September 2008 00:47

rubbish is what we like - clean machines are regular! :)

liaoh75 Wed 24 September 2008 23:39

5 Attachment(s)
Ok, here are the pics I promised to post. Any comments or suggestions would be greatly appreciated. I am far from finished so everything is not very organized and the wires are not very tidy at this point but I'm cutting away. I did not post pics of the computer stuff as that will be changing so that will be coming. I've got a custom made box on the way that is being fabricated as I am posting this.

I've got an idea for routing the dust hose and that will be coming also. I think I'll be borrowing an idea from a car wash. I'll explain that later when I post pics after it is finished.

I've been experimenting with all of the vectric demos and you may recognize a few of the items. I am in experimenting stage where I'm trying to determine what can be cut and with what cutting tools. I will also be posting the cutting bits I've been using. I am still playing with Ucancam and Type3 but find both to have a steep learning curve. I don't know if it's just me not being very CAM savy or the applications are not setup for the average Joe. However, I have to say that I'm leaning toward the Vectric products for their ease of use despite the higher price tag.

Has anyone used Type3 and if so how do you like it? The information I have is that it is from France and is highly respected but from my initial testing, I have to say that it is not very well documented and difficult to use thus far. Maybe I'll change my mind later. I'm using a borrowed security dongle for evaluation.

DMS Wed 24 September 2008 23:58

Really nice CB david. Good going.
How long, what tool and feed rate for Alu plate ?

javeria Thu 25 September 2008 02:59

David, I thought you were going to use the chinese spindle, is it still in your plan?

Gerald D Thu 25 September 2008 03:10

That is a neat location for the laser pointer

liaoh75 Thu 25 September 2008 06:50

Irfan, I AM going to use a Chinese Spindle. However, I had already bought a 3.25 HP Porter Cable production router motor, had it on hand, and couldn't wait so I designed a simple clamp and had it cut out of 12mm thick steel and mounted it to get some cutting action going. The time frame is about two to three weeks I hope. I got your address and will be going to check out the shipping rate to your location from here.

Sharma, the tool I used was a 6mm endmill for roughing and a 3mm ball nose for final but the 3mm ball nose was too short and I program it to run too fast so I gave up on it but will be repeating the same cut again using a 6mm ball nose for rough cut and 3mm extended ball nose for finishing pass going very very slowly. Part of the reason for giving up was the fact that I could not find a good way to clamp the piece down. No matter what I tried, the Big Blue Beast (as I have constantly see it refered to as) is so powerful that it just dug into the aluminium and moved the whole piece along with my crude clamping setup and messed up my 3mm ball nose in the process. Slow, Slow, Slow, as in 3-5 mm a second will be my next attempt. The rough was set at 10 mm a second with a 6mm endmill and that was even a little on the fast side. The aluminium is so soft and melts at such a low temperature, it gummed up the bit and I had to clean it off several times during the roughing pass. I hope I have answered your question.

javeria Thu 25 September 2008 08:43

Hi david thanks for your help! appreciate it. did you also check on what inverter (vfd) they are using?

certain grades of Alu are machinable at such high router RPM we have to select appropriate grade of Aluminium.

just my 2c.

liaoh75 Thu 25 September 2008 10:13

Irfan, the inverter they are using is made by a company called "Sunfar". I will get model numbers and specs later. When I had my lengthy conversation with Mr. Tzao, he indicated that the spindle I will get will be the same as the one that was mounted to his commercial machine but the inverter may not be the exact same one. I'll inquire more about why before I part with my 30,000NT (~$1000 U.S. dollars).

liaoh75 Thu 25 September 2008 10:19

Gerald, you really don't miss much. The Laser pointer is just experimental at this time. It is neither wired up or appropriate setting made in Mach3 yet. Still figuring that out. I have Mr. Tzao checking on the availability of bearing kits for the Chinese Spindle. Sorry it's taking so long as the day job is really getting in the way of all this fun.

BTW: The Module 1.5 rack is working out great without a hitch. Do you see anything wrong with the placement of any of my components?

Gerald D Thu 25 September 2008 11:09

David, no rush on finding out about the spindle bearings - we have 7 spindles lying around at the moment. But I think that other people should also be interested in the bearing aspects.

No, I see nothing wrong with your component placements. You have even got a tiny 0,0 written on the right corner ;)

DMS Thu 25 September 2008 13:05

David, thanks for your input. This is the problem with Alu I was thinking of. May be Onsrud Alu bits help https://www.onsrud.com/xdoc/metal
https://www.onsrud.com/xdoc/AluminumRougher

liaoh75 Sun 12 October 2008 03:36

HELP PLEASE!! + Picture Update
 
5 Attachment(s)
Last weekend, my computer wouldn't boot up. I took it in and they said nothing was wrong so I brought it back and the same problem occured. It freezes in the middle of a cut and the screen gets all blocky and patchy colors. The motherboard was an ASUS with integrated graphics. I did some research and read somewhere that integrated M/Bs are not good for running Mach3. So, I bought a new motherboard, memory, and reloaded everything thinking everything was going to be just like before. Was I in for a shock:eek:!!

Everything appeared ok until I started jogging the X and y axis. What's happening is so strange that it's hard to describe. If I hold down the left or right arrow keys to jog the gantry from one end of the table to the other, it seizes up after a few seconds and makes a strange whining noise. Initially I thought it was the pinion getting stuck so I removed the springs and let the motors hang and tried it again. Again I get the same noise. It seams as if the pulse stream is getting interupted but the strange thing is, it's not just one motor. If I hold down the arrow keys, X1 and X2 seizes up at the same time under absolutely no load. Now get this, the problem doesn't show up when I'm cutting something. It only shows when doing jogs on X and Y axis. Z axis seems fine at the moment. If I set the jog speed to 20% of full speed, it doesn't happen:confused:. Is there something going on with the pulse stream?? Does anyone think trying a PCI based parallel port would help?

My motors are tuned according to instructions, I'm fairly sure everything is grounded.

Any assistance on this would be greatly appreciated. I remember reading about a similar situation many months ago on this forum but, I can't find it. Please Help!!

J.R. Hatcher Sun 12 October 2008 06:14

David my guess is it's in the motor tuning setup. It sounds like you are over driving the motors and missing a lot of steps thus the "strange whining noise". We need more info. What type of motors, are they geared, what's the setup in motor tuning, how fast are you jogging when it happens. etc. etc. etc.

Gerald D Sun 12 October 2008 06:23

Have you tried another PC?

Roadkill_321 Sun 12 October 2008 08:18

Hi David, I think it was Doug's thread where he had a similar problem.

I also had this problem and it turned out that I was running the motors too fast.

Try this link http://www.mechmate.com/forums/showt...&postcount=140

Doug_Ford Sun 12 October 2008 19:35

You've got a good memory John.

David,

Same thing happened to me. I tinkered with the settings in Mach3 and if I recall correctly, once I slowed down the acceleration rate, it started acting right. Or maybe it was when I slowed down the jog speed. That was so long ago, I can't remember for sure. But I'd bet a six pack that it's just one of the speed settings in Mach3. Good luck.

Marc Shlaes Sun 12 October 2008 21:05

David,

You are an artist. Your machine is simple, elegant and beautiful. I love your pc box. Where did you get that industrial trackball??? Very nice.

Good job,

Marc

gmessler Sun 12 October 2008 21:44

David,

Your setup looks great. I like the way you have your computer mounted.

Marc,

Here is a site I found for track balls.

http://www.ikey.com/ProductsList/?me...id=11206&jt=1&

Hope it helps.

Greg

Gerald D Sun 12 October 2008 23:10

That "swinging" computer mount is strong enough to carry the control box as well. Nice job!

liaoh75 Sun 12 October 2008 23:46

Thanks to all who have made suggestions and compliments. I started out with the intention of making my build self contained.

Gerald, my intention is to try another PC tomorrow.

JR, Here is the detailed info on my machine:

Motor OM PK296A2A-SG7.2 geared motor
Motor Drives: Gecko G203V X4
B.O.B.: PMDX-122
Power Supply: Antek 35VDC 500VA

Mach Settings:

Metric Mode
Velocity: 17,000 units/min ~ 283mm/sec ~11.15 Inches/sec
Acceleration: 700

When I changed the computer, I didn’t change any settings. I just copied the configuration file over to the new computer. Just a note though, this problem did occur on the old computer as well, but once in a blue moon. The whining noises I mentioned earlier only occur when the motor seizes up.

Another observation: When I had the motors disengaged from the rack as I was doing slow jogging, I noticed that the sound of the motors is not smooth. It almost seems as if the pulse stream is getting interrupted somehow. Also when the motors seize up, they seize up at the same time. It doesn’t seize up one motor at a time.

I read somewhere a while back (not on this forum) that the parallel port that comes with the motherboard is inferior to PCI based add on boards. I remember reading about the fact that dedicated PCI parallel cards pulse smoother and takes some of the processing away from the CPU. Has anyone heard of this?

Marc Shlaes Mon 13 October 2008 06:59

JR has been using one that is integrated for about 7-8 months with no such problems. His motherboard is the Intel "Little Valley" mini ITX.

Richards Mon 13 October 2008 07:24

I'm betting that the problem is being caused by Mach 3 settings. The PMDX-122 break out board should "buffer" any substandard signals being generated by your computer's parallel port.

In your Mach 3 settings, reduce the top speed by 25% and see what happens. If that cures the problem, then play with some numbers between your current settings and the lower settings until you find a number that always works.

You may find that the acceleration needs to be reduced. The ideal acceleration for a stepper motor is not linear. If you plotted an acceleration curve, it would have a steep, almost straight portion, followed by a long curve that allowed the motor to get to its highest speed without missed steps; however, that kind of curve does not work in most CNC environments because you need to move various axes at various speeds. That means that linear acceleration is required. That also means that the acceleration "ramp" needs to be longer than optimum.

There is the possibility that you have electronic noise, but if the problem is repeatable, then electrical noise can usually be ruled out. Noise tends to be random.

DMS Mon 13 October 2008 08:00

1 Attachment(s)
Nice setup David,
Quote:
that the parallel port that comes with the motherboard is inferior to PCI based add on boards.
Have to disagree with that, as most of MM are running on onboard parallel card. Besides all printers are running fine on that port.

I took photo of my TFT with stone age voltage and current detectors - Red- current detector, black - voltage detector.
shows presence of voltage and strong current fields.
Do you have screen between monitor and motherboard ? I can't deduce whether this is the reason of your problem.May be other members may through some light on it.

ps - oops, while I was typing and loading image, Richard posted. Anyway this can be taken as information.

javeria Mon 13 October 2008 09:39

Hi Sharma, that might bee the cause - but usually not - manjeet on one of his plasma cutter had a problem where the problem was a parallel port cable with really thin wires inside and that caused a lot of problem for him - it was solved when thicker wired cable was use for the PP.

Sharma, where did you get the voltage and current detectors i need to get one.
I have high power cables running near my house and would want to see how much we are in the problem.

RGDS
Irfan

DMS Mon 13 October 2008 19:12

Quote:
where did you get the voltage and current detectors
In kabadi bazar:)

javeria Wed 22 October 2008 07:39

David did you solve your problem - if so can you share what had happened.

liaoh75 Thu 23 October 2008 22:34

I finally solved the problem. It had something to do with the computer. I changed it out to another motherboard with INTEGRATED video and everything is back to the way it was before I changed out the first time. I wish I had a better technical answer for those that have been tracking this problem.

Interesting observations:

1) The problem still rears it's head once in a blue moon when jogging, but usually for the first few minutes of powering on. It almost seems as if powering on is producing some ultra strong pulse of EMI that has an effect on the control system. Then as I get going, the problem goes away. It's almost like a capacitor that charges and discharges and after the (EMI "charge") fades away, the problem goes away. I will be moving the PMDX and Geckos to the other control box on the left (see pics above) and all high voltage stuff will be in one box and the low voltage stuff will be in the other.

2) I've lowered my settings in mach to 15,000 pulses per min from 17,000 and that has helped and my acceleration setting is now at 550 vs 700.

Any other suggestions would be more than welcomed.


All times are GMT -6. The time now is 13:30.

Powered by vBulletin® Version 3.8.3
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.