Re: [Emc-users] CNC and Delrin

2008-07-06 Thread Kirk Wallace
On Sun, 2008-07-06 at 18:32 -0600, John Thornton wrote: > Kirk, > > Any insert with a sharp edge and a high positive rake and with a good coating > for > aluminum will work well with Acetal, UHMW and other plastics. I've gone so > far as > to hone the edge with a super fine diamond stone on so

Re: [Emc-users] CNC and Delrin

2008-07-06 Thread John Thornton
Kirk, Any insert with a sharp edge and a high positive rake and with a good coating for aluminum will work well with Acetal, UHMW and other plastics. I've gone so far as to hone the edge with a super fine diamond stone on some inserts to get a better cutting edge. The profile might be accura

Re: [Emc-users] CNC and Delrin

2008-07-06 Thread Leslie Newell
Use the high positive rake inserts designed for aluminium, such as CCGT or DCGT. They work well on most plastics. They also work quite well on wood. As you are probably aware you will end up with long strings that get tangled up in the work. It helps to program in pauses to break the strings up.

[Emc-users] CNC and Delrin

2008-07-06 Thread Kirk Wallace
I need to machine Delrin on my lathe. I have had good results with hand sharpened HSS tools with moderate tip radius, and positive rake for my manual lathe. For my HNC, I would like to use inserts with an accurate profile. A brief search didn't turn up any inserts for machining Delrin. Anyone have

Re: [Emc-users] Lead screw comp

2008-07-06 Thread Chris Morley
What or how are you determining the corrections? If you are using a glass scale, one could write a program to move the axis slowly while recording 256 points of the motor encoder and glass scale encoder then moving in the opposite direction doing the same thing. The glass scale would be consi

Re: [Emc-users] Thanks and help with post processor

2008-07-06 Thread John Thornton
There is some info on this page for post processors. http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Cam John On 5 Jul 2008 at 19:43, aaron Moore wrote: > Hi All > > I have however acquired some rather good windows software, but its > long list of post processors does not include EMC (shame). Is

Re: [Emc-users] Lead screw comp

2008-07-06 Thread John Thornton
I'm not sure how it could be done like that unless I'm missing something. The comp file colums are nominal, forward, reverse. As I understand it you would have to move to a nominal position press the nominal button, move to the forward position and press the forward button then move to the rev