Frustrated PR96 User !!!Please Help!!!

[mfaris]

I am having a persistent problem with my PR96 that I hope someone out there can give me a hand with. Before I get into my problem, let me first describe my setup. I am currently using both Vcarve and Vector 9 to design and create SB part files for fairly basic signs with v-grove lettering. I then use a 400 MHz AMD K2 machine to run the Shopbot software in MS DOS.

The problem that I am having is that the machine is acting like it has a mind of its own when it is cutting (especially when doing the lettering produced by VCarve). More specifically, the machine will start making unexplained cuts in the wood. Sometimes it just makes stray marks around where it should be working, and other times, it drags right through the piece. I first suspected that the problem laid in either Vector or VCarve, however, I believe I have ruled this out in two ways. First, I have painstakingly reviewed the part file codes around the area where the errors are being made, yet I never find anything which can explain the cuts. Second, the preview mode never shows the errors.

This is becoming a real pain since it is ruining my projects, and I have no idea what is causing the problem. If you have any ideas (any at all!) please feel free to email me or post a reply.

Thanks in advance,

Michael
michael@utk.edu (mailto:michael@utk.edu)

[Mayo]

This will sound fairly basic and obvious but sometimes it's the simple things we overlook.

I would recheck all your connections to your motors - at both ends of the cables. Also make sure there is good grounding.

Blow all the dust out of the control box.

Make sure nothing is preventing your Z axis from moving freely - clean any accumulated sawdust out.
It may be loosing steps from debris causing it to hang up.

Try cutting the same problem wording in a different typeface (in scrap wood or foam for testing purposes) and see if the problem goes away.

[gerald_d]

In addition to what Mayo said;

You may be getting electrical interference from other equipment on the same power circuit or from other equipment in the shop (I seem to recall that someone even had a problem with rogue fluorescent lights). Seperate your circuits. Check brushes on motors (router, shopvac, etc.) for getting too short, losing spring tension, and starting to arc excessively.

(The reason for VCarvz files showing up problems is that all 3 axes must run simultaneously for 3D moves - your other work is probably mostly 2D stuff)

[artisan]

Hi Michael. I feel for what you are going through....you are losing confidence in your machine. These guys on the forum will help you ferret out the problem, but I have one major suggestion to point you in a direction. Run one of your part files in foam....like the half inch stuff at Lowes or Home Depot. When you see an error.....pause the Bot and note the line number. Then...using the FG command, try and re-create that move by returning to a line number, say...10 lines earlier. If you can recreate it... or if the Bot simply does the same errant move everytime you run the file....then you know it is a software issue and not a mechanical-electrical problem. Conversely, if you can't recreate the error and it's random....then it most likely is an interference problem or something mechanical. I'm betting it's in your software...either way, it's better to know. Good Luck....D

[mssignbuilder@charter.net]

mike look at your steper motor make sure your gears set screews are tight i had that hapen
to me it will just lose control some times
hop it helps mike

[kerrazy]

Here is a real simple suggestion, that caught me a couple of times.... make sure your safe Z is in place all throught the file. Something commonly overlooked by newer users.

in the beginning, I created a few scraps by overlooking this part of the program.

a good height is .20 and ensure your surface is level, as this will effect all your cuting hieghts.

And again ensure all your cables connections are secure, I would even consider redoing them to ensure that use has not pulled them apart some. it may look fine but may only be making a small amount of contact or may have been pinched over the course of use.


Dale

[Dan Hofer]

I wouldn't rule out the possibility that your control PC is faulty. You described your PC in generic terms - is it homemade?

I manage systems for a contemporary steel mill. We never, never, never (did I say never?) deal with any older or questionable PC's for this reason.

If your machine is expecting a certain signal on one of the ports on your PC and it's not getting it, your results will be questionable at best.

[mfaris]

I just want to say thanks to everyone who either posted here or sent me emails. Your concern is greatly appreciated.

Now after trying or considering most of the ideas which people sent me, the files were still cutting wrong. Frank Smith from Shopbot was nice enough to examine one of my problem part files with the new Windows version of preview mode, and found some irregularities. As a result, I started rexaming all of my procedures for making the files.

One of the things which tried was changing the way in which I brought the toolpath data over from Vcarve into Vector (so that I can generate my part files). In the past, I have used the "Copy to Clipboard PLC" and then used Vector's Edit->Paste Special->PLC Text Data. However, I instead tried saving the toolpaths in Vcarve as a DXF and then reopening the files in Vector. The files appear no different as a result of this, however, I have found that it now cuts perfectly.


I have no idea why the copy and paste process is creating faulty SBP's, but I can only assume that it is a result of a bug in either Vector or Vcarve. In either case, I can deal with it for the time being as long as I know how to get around the bug.

Anyways, thanks again to everyone who either wrote or posted!

[artisan]

I have encountered these DXF "Ghosts" in the past as well. Only yesterday I emailed a file to an engineer who could not read it properly because some of the lines were hidden after the "translation" on his end....and yet it printed just fine. Congrats on figuring out your problem and thanks for updating us....D

[gerald_d]

Darrel, I think that you are talking about something quite different to Michael. Michael is finding that DXF is curing his problem, not causing it.

But you have touched on an interesting phenomena; dxf files (and dwg's too) can get corrupted during e-mailing. The best way to mail them is to zip them first.

[artisan]

You're right Gerald.....I wasn't very clear. I was actually commenting on the translation or moving of information from one program to another. Most times the data translates flawlessly between the programs I use....but there are special circumstances....usually when I am importing data from another source...that require detective work to find the "Ghosts". I've since learned to almost always build things from scratch in my software....rather than rely on someone elses work. The files are much cleaner and there's usually no detective work unless I've fallen asleep at the wheel....zzzzzzzz....D

[sndwestlv@yahoo.com]

I don't own a shopbot yet, I do however own a laser, I ran into this problem, and found that there were nodes in the file that were no connected this ,made the laser cut from this node back to the first node to finish the loop, maybe the problem you are having.

[magickeith]

Mike,

It's not that there is a bug in either Vector or Vcarve. When you copy an object in one program, you are picking up all of the attributes that your source program uses to define this object. When you paste it into your target program, all of these attributes are pasted with it and the results could be VERY unpredictable as the target program may not interpret these attributes correctly. Actually I'm supprised anything recognizable pastes at all. What you are doing now, exporting to a format that both programs are designed to interpret would be correct, Copy and Paste would be.. well.....bad. But you've really already figured that out.