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View Full Version : Slow cuts revisited



jTr
05-28-2012, 01:32 PM
As concluded in original thread, seemed as though reinstall of SB3 took care of USB problems and all other issues, but this one is back:

Slow cuts.
First pass in pocketing or cutout now. Straight line cuts from 24-30" length dropping to about 1/4" per second cut speed. Last sheet was on table over 45 minutes for 8 cabinet sides.

Here are absolutes I can define from a closer study and noting of code lines:

ONLY happens on first cut of a new toolpath.
ALWAYS snaps back to full travel on next line of code and for remainder of cut.
NEVER slows over same section again.
CLIMB cut will be slow for first side of rectangle in clockwise direction
CONVENTIONAL cut will be slow for first side of rectangle in counterclockwise direction.

Does NOT happen on every cutout on toolpath, except this last sheet, which happened on all 8 pieces for final cutout pass (they were identical size cutouts).

Just verified again in partworks - no open vectors and no duplicate vectors in drawing.

Anyone have a clue at all?

jeff

michael_schwartz
05-28-2012, 01:35 PM
Did you load the correct settings for your machine?

jTr
05-28-2012, 01:52 PM
Michael,
Ran setup routine, which had retained my machine's original setup data.
Verified ramping values, which reflected my initial adjustments as well.

jeff

garyc
05-28-2012, 03:31 PM
Jeff...
Can you save a copy of your current settings and install the OEM settings to see if the problem persists?

I can remember something from the past where certain speed and ramp setting combinations caused initial vectors to run at ramp speeds.

jTr
05-28-2012, 05:16 PM
Gary-
looks like I did this at wrong time.
While cutting current sheet, I stopped when it hit a slow spot. Quit program entirely, then reset VR values to originals.
Re-loaded file, selected line to re-start/run file.
Machine proceeded to ramp into cut 18 inches prior to plunge point, resulting in large gouges across ajacent pieces.

After all this, none of it corrected the slow initial vector issue.

What next?

jTr
05-28-2012, 05:42 PM
In an effort to pin this down, I'm re-running file with known instances of slow down, having reset ramp SPEED settings back to factory spec. Each run produces different results.
Appears machine will do a long slow ramp to start point when prompted to "run from here" vs "continue" cutting due to unexpected termination.

1st dry run: Grinding/buzzing sound as motors drive to start of cut, and immediately into slow motion.
2nd dry run: Grinding/buzzing sound as motors drive to start of cut, and this time proceeding at full speed....

By the way - cannot warm up spindle anymore, as USB PROBLEM has decided to rear it's head again.

Didn't the last poor guy with this set of issues cure it with an installation of the new alpha control software?

Just seems the further I go, the more lost my bot and I become...

Time to tell me where the big red reset button is on this thing.

garyc
05-28-2012, 05:59 PM
Jeff....
To avoid an accidental erroneous setting, please save your current settings [U][S], (if you wish) and install the default settings (not just the VR) for your machine by typing in [U][R] and accepting the dialogs with yes or OK. Then select your machine from the list.

In some cases, stopping a file can cause a crash or an erroneous ini write. IF you do stop, reboot SB3 AND the operating system to eliminate a corupted .ini as a problem. If the spindle control is inoperative, unplug it. Work on one problem at a time.

You should be able to air test this, so zero above the table far enough so that the bit will not touch at max depth.

jTr
05-28-2012, 07:06 PM
Gary,
Chris @ support just called and we walked through reinstalling SB3, drivers and firmware, as well as factory settings.
Air cutting suspected file - Chris ran fine @shopbot - still unable to get mine to run same part file without the slowdowns.
Chris thought excessive decimals in code (6 places) were causing a rounding issue, but edited down to 4 places on known problem lines (before and after as well) and still slowing...

Perhaps another cable or entirely different computer?

Thanks!
jeff

ron_moorehead
05-28-2012, 09:45 PM
Hi Guys,

Thanks for the information here. I have been fighting a problem that the software would not find the control box on startup each time. I went as far as reloading the computer back to factory setting with a reformate for the hard drive. I loaded the control software and reloaded my custom settings and the problem would not go away, I tried my computer that is working fine on my desktop and had the same problem, I tried my laptop and had the same problem. The software would not find the control box. So after reading this post I cleared the settings in the control software and did a factory setting load and everything started to work fine the software would find the control box just fine on each start up.

The other problem I found was I had the usb hub plugged into the back of my UPS for the computer and once I moved that to be plugged into the wall things started to work better. Thanks for the idea to try loading factory settings. Who would have figured.

garyc
05-28-2012, 10:13 PM
Jeff...
Does the problem still exist when air cutting?
Is the spindle on? How about when off?
Dust collection on or off?
Have you tried it with the spindle control USB converter unplugged?
Have you done a speed test to see what your comm rate is?

One more thing to try:
Make a rectangle in PartWorks that is the same size and position as your problematic part. Toolpath it using the same parameters. Aircut and see if that file cuts full speed all the way. The DXF import from Sketchup could be funky.

jTr
05-29-2012, 12:17 PM
Does the problem still exist when air cutting? Yes

Is the spindle on? How about when off? Both on or off

Dust collection on or off? Both on or off

Have you tried it with the spindle control USB converter unplugged? Yes

Have you done a speed test to see what your comm rate is? 67.7% - Chris dismissed this as an issue


One more thing to try:
Make a rectangle in PartWorks that is the same size and position as your problematic part. Toolpath it using the same parameters. Aircut and see if that file cuts full speed all the way. The DXF import from Sketchup could be funky.
Already did that several sheets ago and had a purely partworks vector do the same thing. Since I set up new machine in March, have experienced mild forms of this behavior and chalked it up to my inexperience. I've increasingly suspected Sketchup may be introducing issues, which is why I tried that very thing.
Again, Chris has run one of my problem files on a machine at factory with identical hardware to my new machine and had no issue.
BUT - he did qualify this AM that he's running the beta version of control software...
Now analyzing my toolpathing methodology, trying to see if there's a catch there, but Chris and I are suspecting my computer. Have 4 yr old laptop with XP-Pro at home, so may be trying that soon.

andyb
05-29-2012, 08:07 PM
Jeff,
I have almost the exact some problem if I'm reading your post right. I see the problem when it first starts to cut a part but not always on the first part. It can cut several part normal speed and then in the middle of a job will move very slow even though the speed in the SB software shows normal speed until it hits another move command then the speed is back to normal. I haven't had the problem is a long time until a couple weeks ago then it happened one time but not again. Back when it was happening on a regular basis, if I was cutting the same file it would happen in the same point every single time.

I was tell that this is a known issue that doesn't happen on all machines and that SB was looking into it but didn't have a solution.

Andy B.

jTr
05-30-2012, 12:07 PM
Andy,
Thanks - began to think I was all alone in this issue.
At this point, Chris in tech support is leaning towards a Sketchup hangup. Where do you start with drawing vectors?

At this point, I've run out of time to play much with this issue, but I am having a difficult time believing this is a remnant from 3 programs of workflow ago. Machine is not looking at the "brand" of vectors. Once processed through Partworks and converted to lines of code, it's just numbers.
If these numbers look acceptible to partworks and SB3, it seems to me it is an inability for the machine to properly process code or a glitch in software on that end. Uncertain why I'm not being told to run beta version, as my drawings work fine with it at factory.

Trying an older computer next that has windows XP Pro - hoping for best.

I can deal with an incident or two of this on occaision, as machine is wonderfully accurate - just not certain why I have both this and USB issues...

ssflyer
05-30-2012, 01:00 PM
I had this issue once, about 5 or 6 software revisions ago. It cleared up when I updated (or maybe downgraded) the SB3 version. It would seemingly randomly slow way down in a cut, then speed up sometime later, when it changed direction.

srwtlc
05-30-2012, 01:50 PM
Jeff,

You've already tried and stated that it behaved the same way with a rectangle drawn and processed in PartWorks, so it's not a SketchUp issue.

Your speed test is border line to below.

jTr
05-30-2012, 03:27 PM
Scott,
I agree speed test seems slow. Tried a hub directly on laptop to no avial, but again, support team not concerned in the least about that number, probably as it pertains to this issue (may still be pertinant for other symptoms).

HOWEVER - Frank and I just had a moment of clarity.
Noticed Z plunge rate was @.50. Why? because one of the defaults for entering new bits is that rate. As a newbie, defaults rule until further enlightened.

PROBLEM: known bug in SB3 - sometimes issues occur when plunge rates are slower than .6 ips.
Frank had me manuallly edit part file to 1ips plunge rate for all tools in file.

RESULT: I am unable to get machine to slow on lines that consistently slowed in all previous tests!!

I am cautiously optimistic that we have exorcised the ghost from my machine.

Obviously, anyone else with this issue should look @ plunge rates. I will be erradicating all decimal points from my tool database.

Simple solution, steep curve. Hope everyone else has realized some benefit from this thread !

jeff

bleeth
05-30-2012, 08:29 PM
I'm glad that worked for you but there are many materials that must be cut with fractional plunges and even many wood products that a plunge move that fast will dull a bit very quickly. This is the first time I have heard of this one and I am curious what version SB3 you are using as the fastest normal plunge I do is .5 IPS

andyb
05-30-2012, 10:53 PM
Jeff,
I don't think it is Sketchup. I use Aspire. Most of my files that is happens on are imported DXF files to cut cabinet doors.

I use a plunge rate of .5 also. Some of my tooling have a .75 plunge and I never go faster that .75 except on some 3D. The next time it happens to me I will try to remember to look at my plunge rate. I agree with Dave. A .5 plunge shouldn't be the issue.

On a lot of the files I cut I do a ramp and it normally happens on the ramp until it get to the bottom then the speed is back to normal.

Andy B.

jTr
05-31-2012, 12:04 AM
Dave,
I agree, I'm more inclined to be gentler to my machinery - perhaps I'll simply adhere to .65 to .75.
My machine is 3 months old from factory - latest SB3 software loaded/re-loaded numerous times during this process.
Almost went to beta until we found this.

Note: this is what cured my issue, and as I understand, it is not an issue with all machines - I evidently had the right combination for this to occur.

By the way Dave, Frank relayed a story of a gentleman running 10 ips plunge rate:eek:

jeff

jTr
05-31-2012, 12:20 AM
I don't think it is Sketchup. I use Aspire. Most of my files that is happens on are imported DXF files to cut cabinet doors.

Andy,
I've been fairly certain of that assersion for a day or so now as well. In fact, I've gotten quite comfortable with the whole conversion process lately, but had quite a struggle finding a smooth path from Sketchup to SBParts.

Evidently the slow plunge rate lingers from the plunge into next movement.

jeff