I could use some help solving some problems.

[knight_toolworks]

This is on a prt alpha a little over 2 years old.
I posted last month about some problems I had with connection issues. Removing the USB hub helped but the problems are there but not as bad.
Since I changed the hub and rewired the dc grounding wire the problems don’t happen as often.
I tested two older dell computers both run around 73 on the USB test. I only tested them before I discovered the hub problem. But at the time both computers running the same almost newest (one version below the newest right now) the problems were the same.
The problems now are once in awhile loosing the machine connection. This happens pretty much only when I use the keyboard to move manually or type in a jog command. Two different connection issues one that causes the software to crash and close down. That one I just start the software again re zero and off I go. The second causes the software to crash and I need to use CAD to close the software down and I have to turn off the machine and start it again.
I have had the first problem through three different computers one that was far faster then the others.
Sometimes when I use a jog command the machine moves about the speed of a move command then it looses connection and the machine needs to be turned off.
Since I redid the dc ground I have not have had a problem when running a toolpath file.
Well I have but not the extreme ones above.
The problems I have had running files and some seem to do it worse then others are these. The problem is I get the machine dialed in so the cuts are right on then I run the file a few times and the cut can be off a bit in the x (never checked the y as it was not as critical. This problem was far worse when I had the USB hub hooked up. The cuts were very light and I don’t think it was a hardware issue.
Like a few holes would end up as slight ovals. I was cutting some mdf Friday and the parts were .03 undersize in the y and a little less in the x.
Most of the stuff I make this is not critical and in this case the parts looked fine but I thought I would check them. I tried another bit and it was the same a slower cut speed the same.
Right now the machine has the dc grounded with a wire through the hose to the 6” hose it has a built in wire so I soldered the ground wire to it. Then at the other end where it connect to my main dc I soldered another copper wire and ran that to the black pipe used for the sprinkler system and then to one of the electrical junction boxes. The machine I ran a wire from the rail to the control box and the control box to the power strip my computer is on. I never noticed any difference from that setup.
I am pretty well out of idea’s to try now. But I need to solve this issue.

[Brady Watson]

My recommendation & prescription if I had to solve this would be as follows:

Completely wipe the current hard-drive or buy a new one. Install a fresh copy of XP PRO and only install the minimum of components. Do not install any other type of software, aside from SB3, or Vectric products. Do NOT install ANY software that requires a dongle or auto update. Turn off Windows Automatic Updates, Security Center (do this via Services under Administrative tools). Turn off Sleep, Standby and make sure the hard-drive and monitor will not shut down within 5hrs or your longest running file.

Then install a USB 2.0 card AND a USB 2.0 self-powered hub. You should have communication speeds of around 85% and eliminate much of the nonsense you are dealing with now. All of the goofy stuff you are mentioning I have heard of, and resolved using the methods described here. If you have good grounding & and you are sure you don't have a ground loop (via Wikipedia (http://en.wikipedia.org/wiki/Ground_loop_(electricity))) - then you should be good.

-B

[knight_toolworks]

I was debating on getting a usb card. both of these computers only got to 72 and 73.
both of them had a clean xp install when I bought them about 6 months ago and I turned everything off right away. I can't remember if they came with a copy of xp or not. but I know how to get the key from them. I will try the card first since it is fast.
I don't think I have a ground loop the bot is on it's own circuit that was installed just for it. most of the wiring from the main box is new in this old building.
but I am no electrical guy for sure.
I debated on getting a no0n dell computer though they are harder to find that run xp.

[knight_toolworks]

I jsut tried taking the small extension usb cable off since I was here and no change. here is a wierd one I made 2 circles and a squares cut one of each on the inside and one each outside. the inside cuts were right on the outside .03 too small.

[knight_toolworks]

I will install the card and the new hub tomorrow.

[hespj]

"Right now the machine has the dc grounded with a wire through the hose to the 6” hose it has a built in wire so I soldered the ground wire to it. Then at the other end where it connect to my main dc I soldered another .........to the black pipe used for the sprinkler system and then to one of the electrical junction boxes. The machine I ran a wire from the rail to the control box and the control box to the power strip my computer is on."

I would echo Brady's point about a ground loop. Draw your grounding system on a piece of paper, including the ground wires of the supply system. Grounding in two seperate places could make a loop.

"This happens pretty much only when I use the keyboard to move manually or type in a jog command."

Hmm. Check, check, recheck, check, as Mr Lainchbury our old electrical engineering lecturer used to say. Sounds like your body is having an effect. Static not grounding properly?

[benchmark]

Steve,

What is your ducting made from ? From Shopbot to DC.


Paul

[knight_toolworks]

the building is an old industrial building. the electrical is pretty crazy and there is no real way ti know where the ground is. the junction box that my power box is hooked to and all my power is new and done right.
I know I have had a ground loop issue in my manufactured home and it was hell getting my wifes subwoofer to work.
my hose is all plastic up to the metal ducting for the dc. the metal used to be grounded but i need to check to make sure. then to a plastic cyclone.
I am not worried about the software crashes thats not a big deal but the parts getting cut wrong. I know they both go together. I have had the basic software crashing for almost 2 years now.

[knight_toolworks]

shopbot thinks it is the serial to usb cable on the control box.
I tried the pci card and without and I can hardly run the speed test today on either computer. when it runs if it will it is only at 15.
now if i can only find the cable locally.

[knight_toolworks]

replaced the serial cable 3 hours to fetch it and pay too much at best buy. now I can connect again.
the new pci card did not make a speed difference. but a new powered up got it from 73 to 83.

[Brady Watson]

Steve,
A PCI USB card may or may not make communication better. In fact, in some cases, communication speed, via SpeedTest.exe, may actually slow down. The real value of the PCI USB card is the fact that it is completely separate and distinct from any other USB channels on the computer. This eliminates hiccups caused by some USB mice and keyboards, and this is especially true in my experience on Dell brand computers. If you want a rock solid USB, leave the card in.

-B

[knight_toolworks]

I planned on it.
Now to see if the hiccups are over. may take a bit.
I did another cut test and it is better bit still a hair off. I made a 2" and a 4" square cut the 2" with a outside profie and the large with a inside cut using a 1/2" bit. I checked the bit size and it was .497 or so the outside cut came out to 1.98 per side. the inside cut was right at 2"x2" I got the same thing with a 1/4" bit. both cuts were conventional direction and only 1 ips at .5" cut depth.

[knight_toolworks]

now I am wondering if there is more wear on the pinions then there should be. I got about 400 or so hours out of the first set and I am only at about 150 hours on the new set.
thinking about the outside/inside cut is only really cut direction to the machine.

[knight_toolworks]

replacing the serial to usb cable a new hub and network card has seemed to have taken care of my connection issues.
I still get a glitch here and there. like when I run a c9 command it just lift up the z 3" and jogs to the back of the table once in a while it will not job but move at move speed. when this used to happen I would have to turn off the control box to get the connection again sometimes. now I just stop it and do c9 again and it works.