What's causing this?

[srwtlc]

David,

If you air cut this part, can you see any indication of a dwell at that point? If it pauses at all at that spot, you could get those marks from deflection in the gantry when it takes off again.

Try cutting at a different location on the table. Maybe you have a slight divot/nick in one of your rails.

VectorCam, not the fastest tool in the tool box, but if you learned how to use it well, there wasn't much you couldn't do with it. I still use it from time to time when I need a custom toolpath that can't be done with anything else.

If you can't find a mechanical reason, I can take a look at the file for you Dave.

Scott

[meatbal80]

I had a similar problem due to my PC router. I found that the speed up ramp was to fast and did not alow for my PC Router to speed back up from in time.

[dhunt]

Try cutting at a different location on the table. ===> Further 'out' in Y...hmmmm...
Maybe you have a slight divot/nick in one of your rails.

If you can't find a mechanical reason, I can take a look at the file for you Dave.

I had a fairly intensive look at the numerics of the cut-file myself.

Because the file has radiused corners, it's easy to ID the turning-the-corners lines of code
and therefore the straight bits too, between the corners.

I've identified the straight bits -per plunge- as it goes deeper and deeper over 6 passes, down to -1.80 inches
and there's no visible reason in the numbers, for this groove!


I've always suspected a physical,mechanical reason for this problem
and think your suggestion re. a nick in the Y rails is getting close!

Will check that out tomorrow, definitely.


Given that the rails on this machine are "only" ten years old
and have suffered abuses at the hands of 'local' guys put to run the machine
i.e. total indifference to maintenance,adjustment,tightening,lubrication and other such 'bothers'
nothing surprises me or the boss, any more!

You should see what came out of the little grooves in the stainless wheels that run on the rails!!

[gene]

I cut some doors , 3/4 mdf and noticed that there were marks exactly like what is shown here , I used a 3" ramp and the marks were at the spot where the file ended . can you add a lead out without adding a lead in ? I am using aspire 2.5

[ken_rychlik]

Gene, The first thing I would do is tune up the machine and get rid of all mechanical slop that you can.

If you can't help it that way, you can create you own tails on the part to enter and exit with. The software will do lead in, but not lead out.

[dhunt]

- first thing I would do is tune up the machine and get rid of all mechanical slop that you can.

Mechanical slop is probably half the problem with this (Yr.2000!) PRT-96 I'm using
particularly after a Cuban guy has been using/misusing it for the last 3 yrs.
I say no more. Machine rehabilitation continues...

[tmerrill]

Ken,

Gene said he had Aspire 2.5 and it WILL do lead-outs, however it will only do a lead-out if you have set up a lead-in.

Same is true for V-Carve Pro/Partworks.

Tim

[bleeth]

Can you select the lead in toolpath and delete it?

If not you can modify the code by taking out those lines and substituting it with a plunge at the right point.

[ken_rychlik]

Tim,

Now I have to go back and look at those again. lol

[dhunt]

If you can't find a mechanical reason, I can take a look at the file for you

Let's have a look at the latter section of the .sbp cut file
that liberates the box from the surrounding material.



After initial plunge to depth -0.3017 ......

CG,,3.5000,-0.2500,-0.6250,0.0000,,1 <=== turning the corner code
M3,0.3750,-0.2500,-0.3017 <=== short leg of the box
CG,,-0.2500,0.3750,0.0000,0.6250,,1 <=== turning the corner
M3,-0.2500,5.2500,-0.3017 <=== long leg of the box
CG,,0.3750,5.8750,0.6250,0.0000,,1 <=== turning the corner
M3,3.5000,5.8750,-0.3017 <=== short leg, across the top..
CG,,4.1250,5.2500,0.0000,-0.6250,,1 <=== turning the corner
M3,4.1250,0.3750,-0.3017
M3,4.1250,0.3750,-0.6033 <=== Second plunge depth begins here
CG,,3.5000,-0.2500,-0.6250,0.0000,,1
M3,0.3750,-0.2500,-0.6033
CG,,-0.2500,0.3750,0.0000,0.6250,,1
M3,-0.2500,5.2500,-0.6033
CG,,0.3750,5.8750,0.6250,0.0000,,1
M3,3.5000,5.8750,-0.6033
CG,,4.1250,5.2500,0.0000,-0.6250,,1
M3,4.1250,0.3750,-0.6033
M3,4.1250,0.3750,-0.9050 <=== Third plunge depth begins here
CG,,3.5000,-0.2500,-0.6250,0.0000,,1
M3,0.3750,-0.2500,-0.9050
CG,,-0.2500,0.3750,0.0000,0.6250,,1
M3,-0.2500,5.2500,-0.9050
CG,,0.3750,5.8750,0.6250,0.0000,,1
M3,3.5000,5.8750,-0.9050
CG,,4.1250,5.2500,0.0000,-0.6250,,1
M3,4.1250,0.3750,-0.9050
M3,4.1250,0.3750,-1.2067 <=== Fourth plunge
CG,,3.5000,-0.2500,-0.6250,0.0000,,1
M3,0.3750,-0.2500,-1.2067
CG,,-0.2500,0.3750,0.0000,0.6250,,1
M3,-0.2500,5.2500,-1.2067
CG,,0.3750,5.8750,0.6250,0.0000,,1
M3,3.5000,5.8750,-1.2067
CG,,4.1250,5.2500,0.0000,-0.6250,,1
M3,4.1250,0.3750,-1.2067
M3,4.1250,0.3750,-1.5083 <=== Fifth..
CG,,3.5000,-0.2500,-0.6250,0.0000,,1
M3,0.3750,-0.2500,-1.5083
CG,,-0.2500,0.3750,0.0000,0.6250,,1
M3,-0.2500,5.2500,-1.5083
CG,,0.3750,5.8750,0.6250,0.0000,,1
M3,3.5000,5.8750,-1.5083
CG,,4.1250,5.2500,0.0000,-0.6250,,1
M3,4.1250,0.3750,-1.5083
M3,4.1250,0.3750,-1.8100 <=== Sixth and final plunge
CG,,3.5000,-0.2500,-0.6250,0.0000,,1
M3,0.3750,-0.2500,-1.8100
CG,,-0.2500,0.3750,0.0000,0.6250,,1
M3,-0.2500,5.2500,-1.8100
CG,,0.3750,5.8750,0.6250,0.0000,,1
M3,3.5000,5.8750,-1.8100
CG,,4.1250,5.2500,0.0000,-0.6250,,1
M3,4.1250,0.3750,-1.8100
J3,4.1250,0.3750,1.6000
'MOVE TO X-Y HOME POSITION & THEN RAISE TO Z HOME
JH,
'DONE

...............................

Those lines of code in bold purple are the lines on which the groove is happening.

This is a simple rectangle being cut, with radiused corners.
Two long legs - in and out
Two short legs, one across the top ..the other at the bottom, near to me the operator

Looks like fairly straightforward numerics to me...
What do you think?