Barrel setup???
A few questions about barrel setup and reamers:
How do you cut 60 degree on the barrel blank when getting ready to thread between centers?
How do you indicate the bore for crowning?
Is it possible to convert solid pilot reamers to floating pilot?
Thanks
vr
MR
08 March 2003, 19:52
hornetguythe way I indicated my barrel for crowning was to turn a piece of brass down to a snug fit in the bore, and indicated it in. I had the end of the barrel about 4-6" out of the 4-jaw chuck, as I recall.
09 March 2003, 03:35
Jim KobeYou can buy minus guage pins from J&L industrial online for about $2 apiece. If you get a few assorted sizes, they will fit the bore of most anything you need. For instance, if you do a 6mm barrel, the bore size is somewhere around .236 or so. Get a .2355, .2360, or a .2365 minus guage which are about .0002 under nominal. If you use these in the bore and indicate off them you will be damn close. If you want to cut a 60 deg center, after you indicate in the bore, turn your compound to 30 deg (60 deg included) and use a single point tool to cut. As for the reamer question, Dave Kiff of PPG can re-do your reamer for you.
[ 03-08-2003, 18:37: Message edited by: Jim Kobe ]09 March 2003, 13:47
D HumbargerJim do you have the J&L website addy?
09 March 2003, 17:14
RobgunbuilderI indicate a barrel into a four jaw and spider on the back of the headstock.I do this using dial indicators on both the front and rear of the barrel simultaneously using a four jaw and spider with a piece of brass rod tightly fitted to both end of the barrel. I then use a 60 degree cutter from JGS#0-4 with a piloted insert held in a reamer holder on the tailstock. Turn the barrel around, re-indicate and re-cut the second 60 degree center.-Rob
Thank you for the valuble info for a beginner.
vr
MR