View Full Version : line boring, sort of

07-29-2012, 09:45 AM
Anyone use a rotobroach or mag base drill to refinish a worn bore [i have one on the end of a mini digger dipper arm], it seems workable but the dipper is 5" thick, and the bush i have made from a piece of steel tube is 35mmbore for the pin and 42mm or so outside dia.
can a mag base deal with a boring bar or do they only take shell cutters?
any ideas?

loose nut
07-29-2012, 09:51 AM
Mag drills come in different configurations, straight drill and sluggers are two. Most don't have the stroke you would need, maybe yours does but they usually are not considered a precision instrument. It would take some ingenuity to get it to work .You must have an idea in mind to do this, let us know if it works out.

J Tiers
07-29-2012, 10:14 AM
What loose nut said.....

My suggestion would be to make a couple of bearing plates to fit the bar, and run the whole deal with some form of portable drill motor if you have to, or any other available motor. That will get you better alignment, and a smoother bore.

Bar needs to be twice the length of the bore, plus two bearings and enough extra to "grab" it with the drive mechanism.

John Stevenson
07-29-2012, 10:30 AM
Take a look at this thread.


Which links to the original thread in post #10

07-29-2012, 10:34 AM
post #5 here


has a mag drill driving a cutter bar held in bearing blocks.


07-29-2012, 10:40 PM
thanks guys, i like the lineboring rig john and Robs shoptalk thread was what i was thinking, certainly not as elegant but get er done!