Missing Comm

[gsartor_1999]

New Desktop keeps dropping the connection to the machine and I get the "Missing Comm" error. How do I prevent that from happening? If it does happen, I have to re-zero everything when I get it back up, right?

[michael_schwartz]

what are the specifications for your control PC?

[MogulTx]

Make sure you are WELL grounded. Then start investigating what other programs might be on the computer (and take them off if possible). Then you need to disable all automatic updates ( Windows updates. Microsoft Security Essentials, etc., etc., etc.)

Then you will need to start checking on communications speeds and see if you have trouble there and if you will need a USB Hub... that is one thing I have not had to do, and so I can't help with the recommendations on that, too much.

[paco]

New Desktop keeps dropping the connection to the machine and I get the "Missing Comm" error. How do I prevent that from happening?

You probably need a new PC to test this... yeah, it suck... It's been a "classic" for awhile. I heard laptop are more dependable regarding this (still pending) issue.

If it does happen, I have to re-zero everything when I get it back up, right?

Correct. Just like whenever you suspect it to have lost "something". I hope you have accurate sensors...

[michael_schwartz]

Its advisable to start with a fresh install of your OS. XP Pro is recommended, but I have heard that people have been using 7.
I believe there are known issues with XP home.

Make sure you really are running off a USB 2.0 port. Dells are known to have USB com issues.

I just had a round of "major com issues" and I attribute them to the following. The problems were solved by replacing my control PC. So far I am back up and running reliably, and in some ways I am getting better performance from the shopbot.

#1 I had been running off USB 1.1 on a temporary basis after my USB 2.0 card went bad. This worked initially but I quickly started to have major problems.

#2 I was using a Dell. This worked well enough at first when upgraded with a USB 2.0 card, however there were some things that were never quite right.

#3 I had never truly disabled un necessary background services, etc...

#4 I am 100% certain that there were viruses, or other malware in the background, attempting to access the internet, or network, while causing other problems. Once XP gets infested, I don't care what any IT expert says, even the best antivirus software will not "sanitize" your pc.

I attribute this to the fact that I had numerous problems with viruses on my design PC, that I suspect may have made their way to my control PC via a thumb drive. I have since upgraded my design PC to windows 7 which is much more secure.

It is advisable to start fresh for this reason. Its a good idea to erase and reformat any USB thumb drives.

I also ran a bare copper wire through my dust collection hose, but I don't think my problems were related to static.

I am also using an uninterrupted power supply, and a powered USB 2.0 hub, dedicated to the shopbot connection. These are fairly important.

If you give tech support a call they can walk you through the process of checking your com speeds and troubleshooting the USB connection.

[gsartor_1999]

Thanks for all the info everyone! I am currently running a school environment off my school issued laptop which is running all sorts of other stuff that I probably cannot control. I may have PC at home that I can use as the dedicated machine.

Is it also common to have to force quit the program from the task manager after dropping the "comm"? That seems to be the way to at least get it running again. Thankfully the XY zero seems to have stayed (I was in the process of a bit change so I zeroed that) and what I was working on was still lined up perfectly. I was just cutting some cheap foam but it was nice to know.

[GDGeorge]

If you have a dust collector hooked up, it might be worth checking the ground on the collection hose. I'm having a very intermittent issue that I can't repeat regularly but am thinking along those lines right now. (Or maybe it went away... I haven't seen the error since I added the separator...)

Jerry George

[MogulTx]

Gina,

You are probably going to find that you need to fix the grounding AND that you have some other program searching and therefore interrupting the communications. Once you get a machine that is STRIPPED of other interferences, you will probably be fine. I have had 3 ShopBots and have fought comm issues on one of them ( HP machine, not Dell.) It was the grounding, not the computer... (but interfering programs are just as likely at this point.) I also don't believe you need a fresh load of XP to fix it. Go at this with a "test and eliminate" approach and you will be much more confident and accurate. --- And use ShopBot Tech Support. They are FAR better than we are!!!!

[myxpykalix]

Gina,
Here is a practice I started from the beginning that has saved me on more then one occasion. First i'm not familiar with the desktop but i think these procedures will work.

Ordinarily I set my x,y zero in the center of my material, so i measure and mark my center of the material with a pencil.

Then I do a C3 and it goes to 0,0 (lower left) of the table.

Now I manually move the bit over to the center of the material where i marked it and make note of the X and Y values on the screen and write them down on a sheet of paper.

Then I Zero my X and Y over my center of material. I do a C2 to zero my Z.

Now regardless of how much you cut from the center or if you lose comm and have to shut down or have to start over, to find your exact center all you have to do is do a C3 to go back to table 0,0 and then move your carriage back to the coordinates you previously wrote down and you can start from there.
Another tip is (this is mainly for 3d carving) is that if you are say an hour into carving and you lose comm if you can see the line you stopped at (or close to it) you can do a (F)ile (G)o to and input that file line number and it will get you back to the place so you can restart the file from there rather then starting all over.
HOWEVER, you need to make note where the carriage stops physically in relation to your workpiece BEFORE you do the above mentioned things and manually move it back to that location or the carriage will run right across your work and destroy it.
Another thing i do, especially if it is a several hour carving job, is i usually keep a running tab of the time, the line number and the percentage of cut every 5 or 10 minutes or so because if you lose comm or or problem and you lose your line numbers you can go back to the last written down numbers.

I'm sure there are other "nuggets" of wisdom and experience I can impart to you but those will cost you a nickel apiece!

[jTr]

Gina,
I played with speed settings while dry running my new machine this week. Started getting comm errors. Oddly, I could run small circles, but as soon as I hit 5" or larger, dreaded comm error showed up. I realized it was not likely a ground issue. Started to investigate diagnostic paths to find out if my USB port was up to performance levels in my brand new laptop. Then recalled I had adjusted speed of X/Y travel(wanted to see how fast it would go!!) Dropped back from maximum setting of 12 (!), back to initial setting of 4. Presto!
Will still test my USB, but at least won't be pulling wires out along with my hair!

Footnote: Why were only large circles a problem? Possibly because motors/data did not ramp up to high enough levels to drop comm(?)

Jeff

Roltgen's Woodworks
jeff@roltgenswoodworks.com