OK. . . here is one for the experts

[CountryWoodCrafts]

I am cutting door panel inserts that I need to cut out of 1/4 oak.
I created the pattern and did a pocket cut-out of the squares and rectangles.

**Problem. . . .only one of the corners of each cut out is square. . .the rest round out.

I then created a profile tool-path so that I can tell it to start on the vector start point.

This now gives me that corner squared out. . . . problem is that you have to do this 4 times with different tool-paths.

And if you for any reason hit recalculate . . . then screw up the previous ones that were for the other corners.

I have tried every tool in the aspire to see if I can't correct this but can not.

****Real Problem**** All of you that (would have if this forum let files get posted) download it will not see the problem. . . you have to actually cut out the piece
to really SEE what the problem is. . . this problem is going to show up in everyone's project at some time. . . .

The only real solution I can see would be if they gave another tool in aspire the allows you to re-cut all corners to clean out where the mathematics failed.


Here is a link to the file I am talking about (that this forum won't let you post)
http://www.vectric.com/forum/download/file.php?id=23677

[kghinsr]

do you feel that this is a G-code failure
or do you think its a Mach3 failure
Ken

[Buc]

I tried running your .CRV file on my machine and I got simular results as you. I slowed the feedrate down to about 40" per minute and got better results but the corner radius' are much larger and uglier than they should be. I only tried profile cutting but I think I could get better results with a pocket cut. The vectric software is OK. This is just my opinion. The problem lies within the limits of the shark controlled and the shark machine itself. Tried adding a G61 to the post processor and editing the tap file by removing the G64 and adding the G61, no luck yet. I get an error when loading the .tap file into the contoller in line 9. The one good corner radius you get is where the bit plunges into the work piece. Also, I'm not an expert.

[CountryWoodCrafts]

I thank everyone that replied. I will be trying the suggestions. . . I also posted this on Vectric's forum and had good responses as well.

One gentleman actually did my cut and modified settings and posted them. . . below is an exert from his response and should be the fix

I selected the "use large area clearance tool" option and used the same setting as Country for a 1/8" clearance tool. I changed the finish pass tool to run 50ipm with a 10% step over. By selecting a 1/8" tool for both clearance and finish, you don't need a tool change. But you get a better tool path by including a clearance tool.

forum posting
http://www.vectric.com/forum/viewtopic. ... 83&start=0

[fison]

One of the things I've found is that the default precision setting is set to .1 inch. Its kind of like a 'how close is close enough' setting and allows the machine to transition smoothly but causes precision cuts to be off. There's a line in your G-code files that sets this value. You can change it by doing the following.

edit your G-Code file with notepad and look for an entry like this:

G64 P.1

You can do one of two things:

1. Change the entry to read:
G64 P.0001

this will force the machine to cut as close as possible to the points. Forgot what the absolute precision on the Shark is but it won't do any tighter than that.

2. Change the entry to read:
G61

this will force the machine to go exactly where you told it to go and it will be very jerky so watch the feed rate and slow things down if it gets too jerky.

I do #1 for most cuts and #2 when it really has to be on the mark.

Hope that helps.

[Buc]

Paul,

Are you running the shark control panel or Mach3?

Buc

[CountryWoodCrafts]

Shark Control panel

[fison]

I'm using the Shark control panel. If I was smart enought I'm sure there's a way to set this in V-Carve or Aspire.

[Buc]

I did some editting to the .Tap file and Post processor, but now I get an error while loading the .Tap file into the Shark control in line 9. Not sure what is up with that. I know it did help to lower the feedrate. Also been wondering if adding an outside radius to the rectangles, and squares would help.

Buc

[fison]

Just created a TAP file, made the edits I discussed in the earlier post, and it ran just fine.