PDA

View Full Version : Boring Bar Design Advice



Nate Davey
07-14-2011, 6:17 PM
If you were given 12' of 1" bar stock, what lengths would you cut it too? Already have some hand held hollowers. Looking down the road a bit to making a captured or articulated set-up.

Curt Fuller
07-14-2011, 8:41 PM
I would cut one about 18" and try that for a while. I'd the rest of the bar in one piece until I decided what you want if the 18" bar was too much. I don't turn anything much larger than 12" diameter and usually even shallower in depth so 18" is plenty of bar for me.

Harry Robinette
07-14-2011, 10:42 PM
If your looking at making a boring bar and a trap you want to look at about 3' to 3 1/2'. That should give you about a 10" to 14" in depth of cut. A 1" bar starts to flex at around 13" and gets pretty iffy at about 14".
Just my $.02

Jeff Nicol
07-14-2011, 11:11 PM
Nate, It all has to do with what you want to build, if it is a articulated hollower it will much different than a captured system. I would decide what you want most and then come up with a design that you like and get all the materials needed to complete it. Do some research on the other shop built units and some of the commercially available ones and come up with the one you want to build. Since I have been designing and building things for 35 years I guess I have an advantage over a lot of folks who want to build their own tools. So far I have not made a captured or articulated system as I like to use hand held hollowers, I like the connection and feel of the wood as I cut away the layers of wood and it gets thinner and thinner. Some day I will get one made of some sort, good luck with your project.

Jeff

Eric Gourieux
07-14-2011, 11:19 PM
I recently make one out of 3/4". It measures about 12 1/2" tip to tip. I use it in my Sorby handle or attach it to my home-made articulated rig. Works great for me. I use carbide tips with it. Sounds like you may be making deeper HF's that I.

201921

Bob Haverstock
07-15-2011, 5:52 AM
If your looking at making a boring bar and a trap you want to look at about 3' to 3 1/2'. That should give you about a 10" to 14" in depth of cut. A 1" bar starts to flex at around 13" and gets pretty iffy at about 14".
Just my $.02

Nate,

From my experience with my shop made captured bar, Harry is right on the money. I made mine out of 1 inch diameter cold rolled with a max depth of 16 inches. At that depth, a bigger stronger heavier bar would be a major improvement.

Bob Haverstock

Rick Markham
07-15-2011, 2:30 PM
Just out of curiosity do you know what type of steel the bar stock is?

Nate Davey
07-15-2011, 5:34 PM
Rick, it's cold rolled,

Thanks all for the advice. I think with twelve feet I may be able to do a captured and an articulated system. My plan was to make the cutter end removable for various different heads.