Nightmarish Surfacing Issues

[sevans]

I was surfacing today and my bot was possessed or something. Take a look at the photo to see where it dove in deeper. What Tha? Any suggestions would be most appreciated. Over, Sarah
3804

[harryball]

Routine stuff to check would be pinion, bit is tight etc...

I can't tell how far it runs in the photo but it looks like something similar that happened to me. My PC would get an interrupt while surfacing at high speed, it would slow down or stall sharply creating deeps cut spots in the table as the gantry flexed. It happened ever so often and I finally discovered my PCMCIA network card was dropping and coming back. I now eject it before doing any cutting.

Hope that helps...

/RB

[Brady Watson]

Sarah,
There are a few things that can cause this:

Hardware:
Make sure that your v-roller bearings are in contact with the the rails completely. Grab the router and wiggle it in all directions, listening for any noise that might indicate that they are non completely seated. If you here or feel anything, adjust the v-rollers so that they are seated on the rail.

Grab the Z-axis/router and push/pull it up & down. Do you hear any 'ticking' or feel any movement when you do this? If so, your Z axis pinion either needs to be adjusted or replaced. Is it greased?

Software/Computer:
If you surfaced the table at a high rate of speed (greater than 6 IPS), and your computer is not up to par, the tool can 'choke' because it cannot get fast enough communication, causing erradic movement or errors in position. Run the 'SpeedTest.exe' in the C:\Program Files\ShopBot3\Diagnostics folder and see what your communication efficiency is. If it is below 75%, I would recommend plugging a USB 2.0 hub into your USB port and then your SB USB into that. If running a Dell brand computer, buy a Belkin 4-port 2.0 USB PCI card & install it in your computer. Then plug a 2.0 USB hub into that. I have found that Dell USB interfaces really leave a lot to be desired, and often cause issues with ShopBots when it shares a USB mouse or keyboard on the same BUS as the ShopBot.

-B

[sevans]

Hey. Thanks for the response. I noticed earlier this morning after I posted this that the front v roller on the left side of gantry, as well as the back roller on the right side of gantry were not seated properly on the rails. I tried loosening the rails and riding up and down, then the front roller on left was not riding at all on the rail. Now I'm really frustrated trying to get this alignment correct. Any suggestions on this? Thanks much, Sarah

[Brady Watson]

Sarah,
What model machine are you running, a PRS or PRT? The trick is to get the Z-axis perpendicular to the table 1st, but you must make sure not to have the gear rack to pinion clearance too loose or too tight...and since it is a pretty involved (but not too hard) process, explaining it over the net is a tough one...You don't really want to mess with the v-rollers that are on the same side as the gear rack (PRT models) since they affect how the pinion & rack mesh. If you tighten up a bottom v-roller, you want to move the top the exact same distance or you will wind up making your z axis ride on an angle.

-B

[carvingartists]

Sarah, about two weeks ago i was running the shopbot
surfacing program and WHAM!!!! same thing that happened to you... I figured it was something I did wrong so I ran it again this time it hit so hard that i could feel it in the floor!!! Go back and look at the surfacing program to see if there is a line telling it to slam into the table....I would check that out before adjusting the whole machine..
from what i can tell our machine is pretty true,and i had the same exact problem as you,but only when running surfacing program

Blair

[sevans]

Yep! The surfacing program could be to blame. I know that the surfacing program in my Shopbot software is tweaked. You have to do a comma 1 comma 2 comma 1 thing in the program to get it to drop the z. Brady, I am speaking of the v rollers on the X axis, you may know this already but I wished to clarify so as there would not be a misunderstanding. I have worked quite a bit to get the z axis perpendicular, however, it seems I'm off in the x direction about 2 thousandths of a inch or so. I wonder if it is worth it to shim or un-shim the z??????

[Buckeye Don]

QUOTE "If running a Dell brand computer, buy a Belkin 4-port 2.0 USB PCI card & install it in your computer. Then plug a 2.0 USB hub into that. I have found that Dell USB interfaces really leave a lot to be desired, and often cause issues with ShopBots when it shares a USB mouse or keyboard on the same BUS as the ShopBot."


Brady,
Can this set up be installed in a Dell laptop? Is there enough room to do this or is there a way to do it externally?
I'm only getting 53% on the test and was hoping this would help.
Thanks, Don
C

[Brady Watson]

Don,
It sounds to me like you need to re-load the firmware in your control box. You must do this anytime you upgrade the SB3 control software. Just type in UI in the yellow command box in SB3 and follow the instructions carefully.

To answer your question...sorta. You can buy a PCMCIA to USB adapter from Quatech. They are the best...but try re-loading firmware 1st.

-B

[Buckeye Don]

Brady
I have reloaded the firmware in the past and tried it again. The most I can get is 53%.Is the PCMCIA to USB adapter a card that slides in the side? And will this speed it up considerably?
My Dell laptop is only 2 months old.
Thanks for your help. Don

[Brady Watson]

Don - Yes, it slides in the side & the card is about 1.5 X 3" in size.

-B

[jerry_stanek]

Your laptop should have usb 2 on it check in your device manager and see if under your usb there is a listing for enhanced. Also your laptoip most likly has the new pc express slot and not the older pcmcia slot they do look alike but you will not be able to plug those cards in.