1/2" Indexable Boring Bar

matthewsx

matthewsx

H-M Supporter - Diamond Member
H-M Lifetime Diamond Member
Joined
Jan 2, 2019
Messages
6,539
I have a project coming up where I need to bore ~2 1/2" deep into a ~1 3/4" hole. Just taking a few thousands off and not a critical application.

I am planning on using my Enco boring/facing head on my RF30 mill.

I've already found out I "need" a coaxial indicator to quickly position the workpiece but I'm trying to decide what boring bar I should use. I could get one of the cheap carbide tipped sets but for just a few ($40) dollars more I can get an indexable set from the usual suspects. I figure this is a better bet since I don't have carbide grinding capability and being able to replace inserts is probably a good thing.

Here's what I'm thinking of:


1673727330823.png
Any thoughts on this one or suggestions for better/less expensive tools? I see I can buy an individual USA made tool off eBay but not sure it'll be enough better for me to notice.

www.ebay.com

1/2" SHANK INDEXABLE BORING BAR-APT-MADE IN THE U.S.A. | eBay

1/2" SHANK INDEXABLE BORING BAR. 2-1/18 BORING DEPTH----3-5/8 0/A LENGTH. APPROVED PERFORMANCE TOOLING---MADE ING THE U.S.A.
www.ebay.com


John
 
I would use a decent cobalt boring bar instead of inserted carbide. It will cut cleaner, more accurately and finish much finer. Carbide needs speed to perform well and while a 1-3/4" hole is not too big, vibration becomes an issue as speed increases. I own and have used cobalt, brazed carbide and inserted carbide bars in boring heads and there is no question in my mind that cobalt is the way to go if it will suit your needs.

Another option is a Micro 100 solid carbide bar. Spendy but it will perform just as well as a cobalt bar. It is also stiffer if you need to go deeper.
 
The Amazon bars look like the bottom is full on, which means they're going to chatter like <insert favorite aphorism here> when you're not taking a reasonable cut - like when you reach the bottom. Maybe OK for a through-hole, but not for cutting to a blind hole or much of a shoulder. I'd second @mikey in suggesting a cobalt (or even HSS) bar. If you must use an insert, the CCMT bar that @davidpbest linked looks like a much better option.

GsT
 
This application is a through hole in cast iron, probably no more than .050'" to clean up a vise I bought a while back that's binding.

Of course I want to get tooling that will have other uses as well. Maybe a set like this?

www.penntoolco.com

Precise 10 Piece 1/2" Shank M35 Solid Cobalt Boring Bar Set - 1001-0036

Offering a huge selection of industrial tool sales online. Find over 100,000 metalworking products, precision measuring tools, power tools & accessories.
www.penntoolco.com www.penntoolco.com

I'd only need the longest one for my task, could buy a single but maybe I should be ready for future jobs....

John
 
matthewsx said:
I have a project coming up where I need to bore ~2 1/2" deep into a ~1 3/4" hole. Just taking a few thousands off and not a critical application.

I am planning on using my Enco boring/facing head on my RF30 mill.

I've already found out I "need" a coaxial indicator to quickly position the workpiece but I'm trying to decide what boring bar I should use. I could get one of the cheap carbide tipped sets but for just a few ($40) dollars more I can get an indexable set from the usual suspects. I figure this is a better bet since I don't have carbide grinding capability and being able to replace inserts is probably a good thing.

Here's what I'm thinking of:


View attachment 433623
Any thoughts on this one or suggestions for better/less expensive tools? I see I can buy an individual USA made tool off eBay but not sure it'll be enough better for me to notice.

www.ebay.com

1/2" SHANK INDEXABLE BORING BAR-APT-MADE IN THE U.S.A. | eBay

1/2" SHANK INDEXABLE BORING BAR. 2-1/18 BORING DEPTH----3-5/8 0/A LENGTH. APPROVED PERFORMANCE TOOLING---MADE ING THE U.S.A.
www.ebay.com


John
Click to expand...
matthewsx said:
I have a project coming up where I need to bore ~2 1/2" deep into a ~1 3/4" hole. Just taking a few thousands off and not a critical application.

I am planning on using my Enco boring/facing head on my RF30 mill.

I've already found out I "need" a coaxial indicator to quickly position the workpiece but I'm trying to decide what boring bar I should use. I could get one of the cheap carbide tipped sets but for just a few ($40) dollars more I can get an indexable set from the usual suspects. I figure this is a better bet since I don't have carbide grinding capability and being able to replace inserts is probably a good thing.

Here's what I'm thinking of:


View attachment 433623
Any thoughts on this one or suggestions for better/less expensive tools? I see I can buy an individual USA made tool off eBay but not sure it'll be enough better for me to notice.

www.ebay.com

1/2" SHANK INDEXABLE BORING BAR-APT-MADE IN THE U.S.A. | eBay

1/2" SHANK INDEXABLE BORING BAR. 2-1/18 BORING DEPTH----3-5/8 0/A LENGTH. APPROVED PERFORMANCE TOOLING---MADE ING THE U.S.A.
www.ebay.com


John
Click to expand...
Try this supplier. Meza tool in Eagle Point Or. I use them for my boring tools and am completely satisfied with with them. They use inserts. Prices are good and bars are nice quality.
 
mikey said:
I would use a decent cobalt boring bar instead of inserted carbide. It will cut cleaner, more accurately and finish much finer. Carbide needs speed to perform well and while a 1-3/4" hole is not too big, vibration becomes an issue as speed increases. I own and have used cobalt, brazed carbide and inserted carbide bars in boring heads and there is no question in my mind that cobalt is the way to go if it will suit your needs.

Another option is a Micro 100 solid carbide bar. Spendy but it will perform just as well as a cobalt bar. It is also stiffer if you need to go deeper.
Click to expand...
I quite agree with mikey on this, insert tooling, for the most part do not do well with very light finishing cuts, generally they are not sharp on the cutting edges, fine for rough cuts, not so fine for finish cuts. Personally, I like to use HSS Bokum boring tools.
 
matthewsx said:
This application is a through hole in cast iron, probably no more than .050'" to clean up a vise I bought a while back that's binding.

Of course I want to get tooling that will have other uses as well. Maybe a set like this?

www.penntoolco.com

Precise 10 Piece 1/2" Shank M35 Solid Cobalt Boring Bar Set - 1001-0036

Offering a huge selection of industrial tool sales online. Find over 100,000 metalworking products, precision measuring tools, power tools & accessories.
www.penntoolco.com www.penntoolco.com

I'd only need the longest one for my task, could buy a single but maybe I should be ready for future jobs....

John
Click to expand...
I like the look of that set. As long as your boring head will take a 1/2" shank, that looks like a nice assortment to have.

GsT
 
You must log in or register to reply here.
Back
Top