Messages

1

Building or Buying a Wood routing table.. Beginnners guide.. / Re: Working router table, options to increase travel speed ?

« on: December 17, 2016, 05:42:02 PM »

If you have followed the progress of industrial routers you would have noticed a change several years ago as speed increased.  Indexing speeds are up I use one machine that indexes at 3100 ipm and cuts 3/4 plywood at 1200 ipm all day long.  That's not the fastest machine out there either. In getting to these speeds the manufactures found that the screw would whip and we are talking about 50mm screws, their answer was to hold the screw stationary and turn the nut. But before you get there I think you will run into issues getting enough pulses from a PC controller.  A Windows PC spends a lot of clock cycles doing house work, you do not notice these small inturuptions but they are there and the faster you go the more pulses you need in a given time.

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Building or Buying a Wood routing table.. Beginnners guide.. / Re: shared home and limit switches

« on: December 17, 2016, 05:33:37 PM »

Not sure how Mach 3 or 4 is configured but my experience on industrial cnc routers is that each axis has a home limit switch.  Usually there is an additional switch just past these that is the soft over travel. Usual procedure is to jog the machine away from home position in all axis then set the controller to reference and then this is where Mach is screwed up, you really need to jog all three axis at the same time as it is much quicker.  Anyway jog back until each axis hits its home switch and stops.  The machine is homed,  The machine position DRO should read the same exact numbers as what you have entered in G54 which it will. Load your program and push start. The only time the soft overtravel switches are used is when either the operator or programmer has made a mistake, the keep the machine from going into hard overtravel which is more difficult to get back out of.

3

G-Code, CAD, and CAM discussions / Re: New user can't get a simple circle to cut???

« on: December 17, 2016, 02:08:45 PM »

Rapids or index moves are G0

4

G-Code, CAD, and CAM discussions / Re: How to automatically move to a coordinate after G-Code is done?

« on: December 17, 2016, 02:06:52 PM »

Can you not set a work coordiante for that?  G54 should call the distance from parked or home to the 0x, 0y corner of your table. I have noticed that a lot of home builds do not set a home position and use no work coordinate offsets.  Why is that?

5

Show"N"Tell ( Your Machines) / Re: High feed speed on router results in rounded edges

« on: December 17, 2016, 01:14:47 PM »

The manufacture of the machine did not do their job.  You are experienceing issues with acc/dec, acceleration and deacceleration.  The manufacture should have delivered the machine with these already set. I don't know how far ahead Mach reads the code but on a Faunc 0 controller that I use it is 20 lines.  We have an Anderson Exxact in the shop that is very fast. Indexes at 3100 ipm and will cut 1.125" particlle board at 1200 ipm the controller handles the acc/dec to keep the tool where it should be.  A CNC router should never shake, ever.  when I visit a shop and their router is running I like to touch the machine and see if I can feel it change direction, you should not be able to feel any change when the machine changes direction.  I just reread and you mentioned the gantry shakes, wow!  If the gantry shakes any at all for what ever reason that machine will not give any dependable accuracy.  

6

Mach4 General Discussion / Re: Does Mach4 have "Formula Axis Correction" like Mach3?

« on: December 17, 2016, 11:25:34 AM »

Pedio
Our standard practice is to flycut the spoilboard every shift, this would be your 1.5 MDF table in your case, and then touch off the tools in the changer. this way the operator knows where the machine is at.  It takes us about 2.5 maybe 3 minutes to flycut .015 off the spoilboard and another 4 or 5 to touch off the tools. This is on a 63x145 inch table.  If flycutting is not possible then I would recommend scrapping the MDF and laminating 2 pieces of .75 Baltic Birch and finishing the bottom and edges.

7

Mach4 General Discussion / Re: Does Mach4 have "Formula Axis Correction" like Mach3?

« on: December 17, 2016, 11:21:56 AM »

Bumped the  gantry and now it is out of square?  Need a formula to correct for that?  Never in my 20+ years of working with CNC routers mostly Fanuc controllers have I ever heard of that. New one to me.  I would say that rather than try to correct it with software the construction should be changed.