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skipd1
12-29-2011, 04:50 PM
I have a older 9" southbend lathe and although I have aquired some cutting tools and holders I have nothing for boring yet. I have a Aloris style (AXA) tool holder with several quick change tool holders and a couple of boring bar holders (1/2in.) I like using HSS tooling so I would lean towards those. I have also seen HSS inserts for boring and cutting tools. Is that a good solution? I don't plan to bore anything too large, but being I am just starting out with this machine, I don't really know where it will take me.

Regards
Skip

Boucher
12-29-2011, 05:23 PM
These Everede boring bars work well and are easy to sharpen due to the shape of the HSS bit.
http://i109.photobucket.com/albums/n50/boucherbyron/IMG_0135Small.jpg

There is not anything wrong with the cheaper bars that take the smaller square HSS bits.

The old HSS bars particularly the ones with cobalt alloy were very functional but they seem to be getting harder to find.

loose nut
12-29-2011, 06:43 PM
For shorter jobs the boring bars used in mill boring heads work great in a lathe, very stiff and easy to sharpen. Just grind on the end. Use the HSS ones not the carbide.

RussZHC
12-30-2011, 12:39 AM
Be aware of the Everede bars.

Not saying they are good or bad, I've only got a single unused as of yet 1/2 solid, insert style.

Just my opinion based on information I have found but some of the bars need inserts that seem very difficult to find (insert style) or are to some degree proprietary...just an opinion which I think has to do with the way the pocket is shaped but I'm not certain on that; the cutting bits used for a lathe are most often (?) square/rectangular, sometimes round (home made boring bars as its easier to make a round hole than a square one, ?) but the ones for Everede boring bars are triangular (these are not insert style).

I am by no means saying do not buy them, they are very good bars, everyone who owns and uses them seems very happy and I am still considering purchasing some. As far as I know there is no difficulty in finding those triangular bits and, I think, you only need 4 sizes to fit nearly all the most commonly used bars (they have a "micro" sized set that may use smaller).
They have great information on their website and another thing you should be aware of, they make 30* bars and 10*/15* bars (among others).
The 30* bars are designed for through boring but particularly boring to a shoulder. The 10*/15* bars are for through bores and not to shoulders but they also make inserts for threading for those bars (not 100% sure on that detail going by memory, I know they make pre-ground threading bits in both steel and carbide). They also make bars specifically for circle clips grooves etc.
Additionally, you will have a choice similar to other makers of solid steel, carbide and, I believe, both of those with cooling passages in the bars.

BadDog
12-30-2011, 01:01 AM
I have never fooled with the Everede bars simply because of the cost and/or hunt associated with the bits, not to mention the up front cost for the bars themselves.

For HSS I've always been a fan of the old-school type that take square HSS bits. I've got them from 1" dia down to a tiny little thing that takes 1/8" bits and can work in a min bore of about 5/16". Smaller than that I either use a purpose ground bar, or just find a way other than boring.

But my preference by far is for solid carbide bars. They make life SO much easier, particularly if you standardize on just a few common/cheap insert styles so you can keep different types (application/material) on hand. Did I mention being cheap? Well, taking some time to find used deals, these don't cost that much more than the Everede bars, and they can do things easily that the Everede will have a fit with. I don't mind paying for them a bit, and now that I have them from 3/8" up to 3/4", I almost never reach for anything else. Try boring a very precise hole that requires very good finish at 1/2" diameter over a 4" length in steel. I've done it with my 3/8" Kennametal solid carbide bars that uses common small triangle inserts (don't recall which at the moment). I think I paid less than $50 ($30 maybe?) for the bar, and the inserts I generally get for less than $0.50 each. You just can't beat it...

But I use the old school bars when I need specific ID profiles I can't afford to keep on hand in carbide insert tooling. Things like snap-ring or o-ring grooves, ID threads, and so on. Cut off short they also make great hand indexed broaching tools, for instance for my Bridgeport E-Head slotter.

Boucher
12-30-2011, 10:25 AM
The Everede HSS inserts are available from Enco for $2.21
http://www.use-enco.com/CGI/INSRIT?PMAKA=376-9020
By the time you wear one out you will have acquired a good understanding of boring.

The Everede bar is pricey but it works well and it meets the OPs quest for a boring bar suited for his 9 Southbend that uses HSS bits. You will never understand the good characteristics of these bars starring at it in a box. Try making some chips with it and you most likely will like it. They cut well and they are super easy to sharpen.

The plane old HSS boring bar like these are good but I only see them in sets.
http://www.use-enco.com/CGI/INSRIT?PMAKA=375-2100

Solid carbide boring bars are the ultimate destination but not necessairly the best place to start. The snap you hear when you break a carbide bar is enough to make a grown man cry.

loose nut
12-30-2011, 01:46 PM
http://www.use-enco.com/CGI/INSRIT?PMAKA=376-9020

If you read the fine print on that ad it says they are discontinued.

http://www.use-enco.com/CGI/INSRIT?PMAKA=375-2100

I buy this type from Wholesale tools individually around $9.00 ea I think.

BadDog
12-30-2011, 05:12 PM
Solid carbide boring bars are the ultimate destination but not necessairly the best place to start. The snap you hear when you break a carbide bar is enough to make a grown man cry.
Amen to that... <sniff>

Alistair Hosie
12-30-2011, 05:44 PM
I have a wide selection, mostly kennametal they work great. I would say that with those you won't go far wrong .Alistair

skipd1
12-30-2011, 07:06 PM
Anybody have experience with the A.R.Warner boring bars with their own HHS inserts? I see their sold on the Litttle Machine shop site!

Skip

PixMan
12-30-2011, 09:31 PM
When it comes to boring bars, for me it's been no "selection" so much as plenty of "collection". I've been buying bargains when I find one (if at the same time I have money in the hidden tooling account), and keep upgrading as solid carbide insert bars came along.

As of right now, I've got solid carbide insert bars in 5/16", 3/8", 1/3" and 5/8", one 1/4" steel below that and the 3/4", 1" and 1-1/2" above that, as well as a half-dozen Micro 100 solid carbide resharpenable. The solid carbide insdexable bars are a mix of Sandvik, Kennametal and Valenite.

http://img.photobucket.com/albums/v466/kenm10759/Dads%20shop/IMG_1251-r.jpg

It's taken a couple of years, but the total expenditure to get this far has been less than $170 for all of them. That's less than the list price of just the still-unused 5/8" Valenite VNCD-7462, the 4th one from the top. I do find a slight positive difference in the rigidity of the carbide ones when extending out, but I think more success in chatter-free bores comes from proper insert geometry selection and application than from the bars themselves.

The Micro 100 bars have no top form geometry, but I'm only using them for short bores and shallow counterbores. I also have (available) the 3/4" shank brazed carbide tipped bars that my dad bought from Enco years ago. The ones that still have carbide that hasn't popped off the bar can be used in the boring head on the Bridgeport, I no longer reach for them for lathe work.