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Joseph Hebert
04/26/12 14:11
Read: 1178 times
Okemah, Ok
United States


 
#187249 - tools
Responding to: Mahmood Elnasser's previous message
Hi Mahmood,

I'm afraid I can't speak to the details of how to operate your machine. But the zeroing techniques you describe are similar to those I use on my CNC machine (in my shop, not my LPKF). But instead of a sheet of paper, I use a feeler gauge to set a precisely known gap between the tip of my bit and the z = 0 plane.

So your friend says the smaller the bit the better? Sorry, but I couldn't disagree more. The angle of the cutting tip of your bit allows you to set the width of the cutting path by setting the depth of the bit. Mine have 90 angles and allow me to set the cutting path width from 0.008" (0.2 mm) to 0.012" (0.3 mm). I can use smaller bits that go as fine as 0.004" (0.1 mm) cutting path, but I never use them. If I needed to I would, but frankly I've never needed to.

Since yours are so acute, you won't have much variability. You'll cut through to the other side (or at least to the next layer) first. That's the first reason I would take exception to your friend's claim that smaller is better. It really isn't. It's just more expensive. Smaller bits not only cost more to buy, but they require higher spindle speeds which means they wear out much faster (my second reason), contributing to their higher cost. You should never use a smaller bit than your job requires.

There will be times when you need to clean out the extra copper from a large area of your board (e.g. resonant circuits, controlled impedances). With the tiny bits your friend recommended that's going to take a lot of cutting. You should have some end mills (flat bottoms and vertical sides) for cutting wider paths.

As for your particular machine/software, I'm sorry but I can't really speak intelligently about either.

Good luck,

Joe

List of 74 messages in thread
TopicAuthorDate
CNC      Mahmood Elnasser      04/14/12 10:43      
   Enjoy :)      Oliver Sedlacek      04/16/12 04:14      
      Having fun      Mahmood Elnasser      04/17/12 13:53      
   Congratulations      Joseph Hebert      04/16/12 09:42      
      We looked at buying one of those      Jez Smith      04/16/12 14:09      
         Me Either!      Joseph Hebert      04/16/12 14:17      
            We use a variety      Jez Smith      04/17/12 00:50      
               do not be lazy,Mr.Smith      Stefan KAnev      04/17/12 11:28      
               prototype cost and turnaround      Joseph Hebert      04/17/12 13:31      
                  I'll find the ads      Erik Malund      04/17/12 14:14      
                     googled      Erik Malund      04/17/12 14:22      
                        Ebay deal      Steve M. Taylor      04/17/12 15:08      
                           What about this one then...        Robert Revens      04/25/12 12:59      
                              Follow up on prototype board shops      Joseph Hebert      06/22/12 08:41      
                                 international pcb houses      Mahmood Elnasser      06/22/12 14:13      
                                    PCB Houses      Joseph Hebert      06/22/12 16:55      
            working out of town      Erik Malund      04/17/12 07:20      
      CNC bits      Mahmood Elnasser      04/25/12 06:37      
         answering      Joseph Hebert      04/25/12 11:38      
            it happens      Mahmood Elnasser      04/25/12 14:51      
               what other tools required?      Mahmood Elnasser      04/25/12 15:00      
                  a new trick zeroing Z axis      Mahmood Elnasser      04/26/12 12:26      
                     Z ref      Steve M. Taylor      04/26/12 13:10      
                        Collet type      Mahmood Elnasser      06/22/12 14:27      
                        Z axis reference      Mahmood Elnasser      07/02/12 01:40      
                           Vacuum      Per Westermark      07/02/12 02:35      
               this sort of thing happens often, from my experience      Richard Erlacher      05/01/12 07:38      
                  ctrl+A, crtl+C, submit      David Brown      09/19/12 01:34      
         tools      Joseph Hebert      04/26/12 14:11      
            holding the PCB      Mahmood Elnasser      04/27/12 00:27      
               Holding the PCB      Joseph Hebert      04/27/12 14:06      
                  Carbon steel?      Per Westermark      04/27/12 20:16      
                     Not tungsten carbide      Joseph Hebert      04/28/12 16:37      
                        Just carbide is a bit lazy slang for tungsten carbide      Per Westermark      04/28/12 21:41      
                           If you say so.      Joseph Hebert      04/28/12 22:30      
                  Plate through holes      Mahmood Elnasser      04/28/12 11:05      
                     plating holes      Joseph Hebert      04/28/12 16:46      
                     plated through holes cont.      Joseph Hebert      04/28/12 22:37      
                  2 point registration system      Mahmood Elnasser      04/30/12 14:27      
                     Need not be exactly in middle.      Per Westermark      04/30/12 16:05      
                        is it that simple?      Mahmood Elnasser      05/01/12 00:27      
                     2-pin registration      Joseph Hebert      04/30/12 23:40      
                     Fine pitch milling      Joseph Hebert      05/01/12 23:54      
                        Solder Mask      Mahmood Elnasser      05/02/12 10:28      
                           solder mask and legend      Joseph Hebert      05/02/12 11:47      
                              too much work      Mahmood Elnasser      05/02/12 15:54      
                                 Much work      Joseph Hebert      05/06/12 15:50      
                                    My CNC      Steve M. Taylor      05/07/12 06:57      
                                       Is That...      Michael Karas      05/07/12 10:30      
                                       which cad did you use?      Mahmood Elnasser      05/07/12 15:58      
                                          Limit Switches      Michael Karas      05/08/12 00:22      
                                             Will do      Mahmood Elnasser      05/08/12 10:55      
                                                Little Plates      Michael Karas      05/08/12 16:40      
                                             MEchanical limit switches      Steve M. Taylor      05/11/12 12:50      
                                       Your project      Joseph Hebert      05/10/12 06:18      
                                          This:      Steve M. Taylor      05/11/12 12:38      
                                             very cool!      Joseph Hebert      05/11/12 13:29      
                                             Funnel      Michael Karas      05/12/12 12:37      
                                                Funnel !      Steve M. Taylor      05/13/12 13:04      
                                                   Lawyer or Solicitor - Not ! !      Michael Karas      05/13/12 15:43      
                                                      RIght      Steve M. Taylor      05/14/12 12:16      
                                    vacuum pick and place tool      David Brown      09/19/12 01:29      
            90 degrees bits      Mahmood Elnasser      09/14/12 04:22      
               Z-axis depth control      Joseph Hebert      09/15/12 22:53      
                  stepper       Mahmood Elnasser      09/16/12 06:34      
                     z-axis control      Joseph Hebert      09/16/12 15:37      
   oiling      Mahmood Elnasser      09/29/12 14:49      
      lubrication      Joseph Hebert      10/01/12 10:41      
      Lube      Steve M. Taylor      10/05/12 14:47      
         ballscrews      Mahmood Elnasser      10/06/12 00:21      
            Ballscrews      Steve M. Taylor      10/06/12 14:00      
               Sometimes it's useful for controlling dynamics      Richard Erlacher      10/06/12 14:08      
            ballscrews & table slides      Joseph Hebert      10/06/12 15:15      
   LINUXCNC      Mahmood Elnasser      10/19/12 02:08      

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