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Roy Andrews
01-20-2009, 12:30 AM
the three steps of most projects (good days). follow picture right to left.

1.rough out hole till it looks close. oops 1.420 i wanted 1.345.
2.with the new lathe and no threaded chuck decided to thread in reverse to cut down on drama. first time cut perfect threads wrote down data and bored second sleeve (needed two) get bore right and set up for threads. wont cut, right grinds like dull tool, ugly cut. stone tool. first pass sounds a litle better and looks smoother second cut back to crap. i'm at my target for compound so i do a test fit. not even close, wont start. start to have dejavu (sp) check things and sure enough never put lathe in reverse. have now pressure formed a 1 7/16 16 left hand thread.
3.third time is the charm.

the second photo is the arbor they will go on. it came with my m head and i had nothing to put on it so the two sleeves will be made into a boring bar and a slitting saw arbor.

third is the threading setup.

http://i460.photobucket.com/albums/qq329/joshuaz223/machining/threesteps.jpg
http://i460.photobucket.com/albums/qq329/joshuaz223/machining/arbor.jpg
http://i460.photobucket.com/albums/qq329/joshuaz223/machining/reverse.jpg

will post more pics when done.

wierdscience
01-20-2009, 12:35 AM
Don't feel bad,I single pointed three threads.....of the wrong pitch the otherday.Perfect they were,just couldn't use any of them sniff sniff:(

J Harp
01-20-2009, 12:54 AM
For inside right hand threading in reverse you need to grind the bit like for outside left hand threading. also swing the compound 29 1/2 deg toward the chuck. See if that will help.

Roy Andrews
01-20-2009, 01:37 AM
j harp, i had the right relief ground on the tool and if you look at the bottom of the tool holder you can kinda see that the compound is turned toward the chuck. the threads didn't cut bad but they didn't press well.:confused:

J Harp
01-20-2009, 11:23 AM
I guess I used the wrong wording for the setting of the compound. Your picture shows the compound turned counterclockwise from 90 deg to the bed. For left hand threading or right hand internal threading in reverse the compound needs to be turned clockwise from 90 deg. In other words you want the compound pointing in the direction the carriage will move to cut the thread.

Some time ago someone posted a chart showing various ways to set up for threading, left, right, forward or back rotation, tool right side up or upside down etc. I don't know where to find that chart, couldn't find it with the search feature here. Maybe someone will know where it is and can post it again.

tiptop
01-20-2009, 09:39 PM
Roy,
Good to see you posting, I have not heard much from you lately. Nice looking arbors. Jay

Roy Andrews
01-20-2009, 11:55 PM
j harp, thanks for the input. after thinking about it it made sense to turn it the way you say so that the pull wouldn't be trying to take the play out of the compound.

tiptop, not to be negative but with the cancer induced disability and the forced move and lifestyle changes it is taking a while to get back going. i have some of my machines in my very small garage and am starting to do quite a lot. i hope to post more and give back for all i have learned here.

tiptop
01-21-2009, 12:07 AM
Roy,
Glad to see you back and working. Keep it up and have some fun. Remember we like pictures. Jay