The Cheap Boring Bar Sets

AR. Hillbilly

Registered
Registered
Joined
Apr 9, 2016
Messages
120
I ordered a cheap carbide tipped boring bar set from Shars. I ordered the 5/8' Shank. I needed to use one to bore out a pulley center. I unboxed my AXA boring bar holder and the hole is way too big for the boring bars. I didn't measure the shank yet to see how big they really are.
I had to get this done so I installed one in one of the tool bit holders and used it with great success.
Can I get a different bushing or do I have to buy different boring bars? I don't want to keep using them in a tool holder designed for square tool bits.
This was my first boring project and I needed it done to fix a tool to get a job done. I can't believe how well it worked even though it ws the wrong way to do this. The pulley center had a keyway which made me nervous. I took very light cuts and measured often until it was the right size.
I don't want to create a habit of doing things wrong as a beginner but this did keep 3 men working for the rest of the week.
 
I ordered a cheap carbide tipped boring bar set from Shars. I ordered the 5/8' Shank. I needed to use one to bore out a pulley center. I unboxed my AXA boring bar holder and the hole is way too big for the boring bars. I didn't measure the shank yet to see how big they really are.
I had to get this done so I installed one in one of the tool bit holders and used it with great success.
Can I get a different bushing or do I have to buy different boring bars? I don't want to keep using them in a tool holder designed for square tool bits.
This was my first boring project and I needed it done to fix a tool to get a job done. I can't believe how well it worked even though it ws the wrong way to do this. The pulley center had a keyway which made me nervous. I took very light cuts and measured often until it was the right size.
I don't want to create a habit of doing things wrong as a beginner but this did keep 3 men working for the rest of the week.

My Grizzly QCTP AXA set took a 3/4" boring bar. It looks like the Shars set is similar. If you have an AXA set, the primary diameter should be 3/4" with an adapter sleeve to take it to 5/8".

Unfortunately, the best way to make a sleeve would be to use a boring bar. Catch 22. ;) However, If you get a short nipple of schedule 40 black pipe from your local hardware store, it has a nominal *I.D. of .622" and O.D of .840. If you turn the O.D. the O.D to something like .753" and slit it lengthwise as boostin53 suggests, you should be fairly close to a workable sleeve. I would machine a short length, say 1/2" for a trial fit and adjust my O.D. for a close slip fit. then cut the full length sleeve.
 
Thick bushing; I recently made a bushing for the same purpose (mount 1/2" boring bars in a 1" holder). The wall thickness is 1/4" so I wasn't sure if it would compress enough because of the thickness. Surprisingly, it works great. I was going to cut 2 other slits part way through if it would not compress enough to hold the boring bars but didn't need to. (I used a reamer to finish the I.D.)
 
AR
Pinching the bar, as you did, is not "wrong". It is not as fast or convenient, but there is nothing really wrong with it.

Make your self a sleeve, as others suggested above. You can purchase adapter sleeves, but they really are nothing special to make (perfection I'd not required, as long as it holds the tool securely it does not need to be perfectly straight or concentric). A square holder for that bar is also easy to make, just some square stock, hold it in a regular tool holder, then use the lathe to drill the main hole, swivel the tool post and drill/tap some set screw holes.

Having a square holder is handy for when you need to sharpen that boring bar.
 
I have some round carbide bars that are oversized standard sizes and I make boring bars out of them all the time by silver soldering carbide tips to them. They make super boring bars. Then I hold them in holders made for square tools. And I have been doing this for over 50 years.
jimsehr
 
Some of my AXA holders have a V notch in the bottom for holding round material

Sent from my SM-G930V using Tapatalk
I use the V notched tool holder for small boring bars. I found that the set screws bite into the soft shanks of my bars so I made a cap to fit over the top of the boring bar to keep the boring bar shanks pristine. I did have to machine some extra clearance in the tool holder though.
Boring Bar Cap.JPG
 
Thanks to both of you. I'll do just that. I went to the shop and measured the shank. The boring bars are 1/2" and the tool holder is 3/4" with a bushing that's 5/8" I dug through my plumbing box and found a 6" piece of pipe that the 1/2" shank would not quite go in to. I reamed it to 1/2" and started turning the outside to 5/8" to fit in the existing bushing. When I was done the boring bar shank wouldn't go in the pipe so I slit it full lingth and chucked it in the lathe until the slit was closed and ran the reamer through again. This time when I took it out of the chuck the shank would just slide in. I stuck it in the other bushing and clamped it down. I haven't used it yet to know if it will hold well. Thanks for the idea. I plan to look at more tool holders soon. I get tired of switching out tools in the holders when I could just switch holders with the twist of a lever.
 
I ordered a cheap carbide tipped boring bar set from Shars. I ordered the 5/8' Shank. I needed to use one to bore out a pulley center. I unboxed my AXA boring bar holder and the hole is way too big for the boring bars. I didn't measure the shank yet to see how big they really are.
I had to get this done so I installed one in one of the tool bit holders and used it with great success.
Can I get a different bushing or do I have to buy different boring bars? I don't want to keep using them in a tool holder designed for square tool bits.
This was my first boring project and I needed it done to fix a tool to get a job done. I can't believe how well it worked even though it ws the wrong way to do this. The pulley center had a keyway which made me nervous. I took very light cuts and measured often until it was the right size.
I don't want to create a habit of doing things wrong as a beginner but this did keep 3 men working for the rest of the week.

Just wanted to point out that the square shank tool holders can hold round tools if you machine a small V groove in the center of the bottom face of the tool clamp. All of my quick change tool holders have this groove from the factory, yours may also. I have never had problems with holding on to round shanks with these style of quick change clamps, and I take some large cuts when roughing out projects from castings.
 
Back
Top