Messages

2531

General Mach Discussion / Re: Circular pocket shout out

« on: June 15, 2006, 06:41:29 PM »

Excellent news Keith, theres hope for all.

Graham.

2532

General Mach Discussion / Re: Help with Write Wizard

« on: June 15, 2006, 02:09:56 PM »

Hi,

if you want lots of text have a look at this working demo, it outputs G-Code.

http://members.aol.com/m9685123/Mdemo.htm

Graham.

2533

General Mach Discussion / Re: Circular pocket shout out

« on: June 15, 2006, 01:39:07 PM »

Hi,

I have had great success with 60 and 75 degree cutters, they transmit the cutting force more in the Z then in the X & Y.

The only thing to watch out for is that you have a good hold on them or they pull down in the chuck.

Graham.

2534

General Mach Discussion / Re: Circular pocket shout out

« on: June 15, 2006, 04:22:46 AM »

Is the flat always the same length independent of the circle diameter, if it is then it sounds like backlash or movement in the gibbs, if it varies then it could be cutter pull/push.

If you use very high helix cutters this can help reduse pull.

Graham.

2535

G-Code, CAD, and CAM discussions / Re: Peck Drilling

« on: June 13, 2006, 04:12:13 AM »

Hi Kieth,

Peck drilling cycle works like this :-

Short retract type, just breaks the chip, drill stays down the hole.

G73 Z-1. R.1 Q.1 F3.

Z = final depth of hole
R= safe starting distance above job
Q= depth of each peck
F= feed rate

or

Full retract type, every peck the drill moves back to start position (R) and then rapids back to cutting depth.

G83 Z-1. R.1 Q.1 F3.

Z = final depth of hole
R= safe starting distance above job
Q= depth of each peck
F= feed rate

If you add a G98 to the line it forces the tool to rapid back the the safe start point.

If you add a G99 to the line it forces the tool to rapid back to the R point. You should then put a G98 on the last move 

If you have 4 holes to drill on 1" centers you would do something like :-

N1 (DRILL 1/4" * 2" DEEP)
G54 G00 G90 G43 X0 Y0 Z25. H1 S1000 M3
G73 G99 Z-2. R.1 Q.25 F2.
X-1.
X-2.
X-3. G98
G80
G91 G28 Z0
M30

Graham.

2536

General Mach Discussion / Re: Circular pocket shout out

« on: June 12, 2006, 06:14:27 PM »

Doing a normal circle you only have 4 direction changes,  with a spiral pocket this is multiplied by the number of arcs cut, so the backlash is highlighted.  Also the cutter can be pulling and pushing the table at varying amounts as the circle gets bigger.

Graham.

2537

General Mach Discussion / Re: Circular pocket shout out

« on: June 12, 2006, 05:47:25 PM »

Hi Keith,

The flat could be cutter flex or backlash.

For your information :-

Circular holes can be cut very easy with the following commands.

Hole is at X0 Y0 with a radius of 1.000"

G00 X0 Y0                   (move to start)
Z-.1                            (move to Z depth)
G01 G41 X1. D(offset number for tool rad) F5. (move X pos+radius and use compensation)
G03 I-1.                      (do a full circle cut)
G00 G40 X0 Z1.           (rapid to X start and Z safe)
M30                           (end)

Graham.

2538

General Mach Discussion / Re: Limits HELP!!!!!!!!!!!!!!!

« on: June 11, 2006, 08:06:27 AM »

Hi,

normally the Y axis zero point is to the front of the machine and the X is with the table to its left most point.

If you go to Homing/Limits in the config menu you can reverse the homing direction and set the G28 values.

If you set G28 as X0, Y0, Z0 you then use G54 to position your work zero, this is on offset form zero return to the zero point on the job.

E.g. If you clock a hole on a part and look at the Machine DRO and it says X-5.5000 and Y-3.000 these are the values you enter into G54 offset.

I hope this helps, come back for more if not.

Graham.

2539

Promote and discuss your product / Re: Scanned images to cad

« on: June 11, 2006, 05:16:23 AM »

Here is another that looks interesting.

http://members.aol.com/m9685123/index.html

Graham.

2540

Promote and discuss your product / Scanned images to cad

« on: June 11, 2006, 05:02:49 AM »

I came across this today, thought it may be of interest to somebody.

It converts images to CAD.

http://www.softcover.com/

Graham.