They are not intended for drilling, only enlarging existing openings. Mill a rough hole 1st, using a helical path and a sharp up spiral bit, then finish it off with the boring bar. (Although in wood I'd probably not bother with the boring bar at all and do it all with a sharp carbide two flute endmill designed for cutting wood aka a router bit.)
Todd Zuercher P. Graham Dunn Inc. 630 Henry Street Dalton, Ohio 44618 Phone: (330)828-2105ext. 2031 -----Original Message----- From: gene heskett <ghesk...@shentel.net> Sent: Tuesday, September 20, 2022 5:35 AM To: emc-users@lists.sourceforge.net Subject: Re: [Emc-users] boring bar in boring head advice? [EXTERNAL EMAIL] Be sure links are safe. On 9/20/22 05:06, andy pugh wrote: > On Tue, 20 Sept 2022 at 09:48, gene heskett <ghesk...@shentel.net> wrote: > > But the head offsets in a kit of boring bars are such the a 1/2" wide >> bar, while boring about the >> size hole I need, is also leaving about 3/16" in the center as an >> uncut post sticking up. So I assume that proper orientation of the >> boring bar in the head might assure its cleaning out the center. > > I would typically imagine a boring head to be used to machine a > pre-drilled hole to size. Are you actually trying to plunge-cut with a boring > head? > Yes, the material is hard maple. In metal, yes, I'd bore a starter hole. I probably need to make a jig to hold the workpiece high enough to let this plug drop free, but I don't have, in the go704, enough head room for that, the boring heads length for a 3 incher, take up too much room to allow that. Needless to say, the carbide bar has been re-sharpened until you could shave your arm just trying to get a clean exit hole. 2000 grit CBN is handy for that. Cheers, Gene Heskett. -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author, 1940) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fgeneslinuxbox.net%3A6309%2F&data=05%7C01%7Ctoddz%40pgrahamdunn.com%7C9fa52842cf5845890bf208da9aeb91cd%7C5758544c573f47cebee96c3e0806fb43%7C0%7C0%7C637992633803991090%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=1O%2FWVNE7hQecOB99mShEZxeqPWBWgtwODp2KTehezAg%3D&reserved=0> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.sourceforge.net%2Flists%2Flistinfo%2Femc-users&data=05%7C01%7Ctoddz%40pgrahamdunn.com%7C9fa52842cf5845890bf208da9aeb91cd%7C5758544c573f47cebee96c3e0806fb43%7C0%7C0%7C637992633803991090%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=NeYH6VrmbuoPauf0VQfazNg%2Bs8GwZ77%2FOIBXSnHkXyI%3D&reserved=0 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
