Boring head

[Mr Ron]

I have a Criterion 2" boring head and would like to use it to bore a 3-1/2" diameter hole on my vertical mill. I'm not acquainted with the boring bar that fits the head in the horizontal plane. I'm thinking a straight boring bar with a 90° offset is needed. The setup would look like a fly cutter; am I right?

[warmstrong1955]

Check these guys out.
I have attachments for my 2" and 3" boring heads. I also have some bars & threading bars I picked up from them.

http://www.mesatool.com/products/boring ... tachments/

Bill

[johnfreese]

You can use a square tool bit through the cross hole. Depending on the size of the bit you may need to chamfer the corners for it to fit the hole. Alternatively, you may want to start with a piece of 1/2" round with a piece of carbide brazed to the end.

[Mr Ron]

Check these guys out.
I have attachments for my 2" and 3" boring heads. I also have some bars & threading bars I picked up from them.

http://www.mesatool.com/products/boring ... tachments/

Bill

Thanks; exactly what I was looking for.

[warmstrong1955]

Thanks; exactly what I was looking for.

I bought the Mesa two pin attachments for the 2" & 3" boring head back when I was still milling with a 3 in 1. Needed all the rigidity I could get, and that they are. I have all three on the left side of the page, plus the two bars at the bottom.....and several others.....
Nice that you can spin around the two pin attachments, and bore larger holes too. More rigid than just a bar.

All his stuff is hardened steel. His carbide isn't bad either!
If I'm boring...chances are I'm doing it with a Mesa tool in the boring head. I like 'em!


Bill

[pete]

There a bit tough to find on the Criterion website but they do make a proper 1/2" shank boring bar designed to fit that cross hole in the DBL 202 heads. Very nicely made and works really well. I think if my memory is right you can bore with through holes up to about 7 1/2" in diameter. Obviously slow speeds and light cuts at that size because of the tool tip speed and possible chatter. But the cross hole boring bars are pretty much like a right hand lathe boring bar.

[GlennW]

But the cross hole boring bars are pretty much like a right hand lathe boring bar.

Left hand if you use a threaded shank boring head, Pete.

I like SCLCL bars

[pete]

LOL, busted, your of course 100% right. The excuse? It was late and I was tired and that's the one I'll have to stick with since I've nothing else even semi believable I could use. Thanks for correcting that Glenn. I really like the Narex shank to head attachment design except for the price of the Narex shanks. Imo it's far superior to the more normal threaded attachment like Criterion and all the offshore clones use. The heads can be swung in either direction with no chance of them unscrewing.

[GlennW]

The old, well used, Walhaupter above has an integral Moore shank, and Moore Jig Borers only run in one direction. (hence the left hand bar) My Criterion DBL202 also has an integral Moore shank. I have a basically new Walhaupter that has a removable Moore shank, but I find the slight difference in overall length to be quite noticeable as far as rigidity, which was a discussion in a different thread somewhere, so it lives in it's nice wooden box while the old, shorter, integral shank model sees all of the action.

[pete]

The Narex heads use a precision ground short but fairly large bore in the top of the head and a short ground stub shaft on the shanks end that fits the head bore with maybe .0005 clearance Glenn. The shanks have a flange just above that stub shaft and the shank gets attached to the head with four 6mm? allen bolts. Like your integral shank it's noticably more rigid than the threaded attachment Criterion uses even though Criterion do a very precise thread fit. I looked for over 2 years for a good used Walhapter R8 B & F head at a semi resonable price before finaly giving up and buying the Narex. Have never seen a Walhaupter never mind use one, but I've heard there even better made than the Narex. I haven't been paying proper attention and didn't know you had a Moore jig borer. I'm envious. Too tall and heavy for my shop though.

[Harold_V]

and didn't know you had a Moore jig borer.

Heh! If memory serves, he has three of them. Talk about envy!

H

[SteveHGraham]

I hate to sound like someone's wife, but why would one person need three jig borers?