# Which Boring Head To Get For A Mill?



## Alittlerusty (May 18, 2015)

Hi all, I need(want) to purchase a boring head and boring bar set for my mill. Can anyone recommend a decent mid price brand with some insight . I can't see buying high end for my farm shop and don't want junk that will ruin my parts. The first project for the head will be to enlarge pin  bushing seats on my mini excavator( bucket links, stick, boom etc) the kubota parts r priced insane so intend to resize to common size pins and bushings which can be bought at 1/7 the price of oem. I will be boring steel not alum or brass and don't know the hardness yet but figure replaceable carbide inserts on the bars would be a good idea . Thanks in advance for your help!


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## kingmt01 (May 20, 2015)

I bought a kit off eBay for $80. It has the carbide brazed on but you could make your own indexable or buy them later. It being the only one I've ever used I don't have anything to compair it to but the screw seems a little slopy to me but works just the same.


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## Uglydog (May 20, 2015)

In addition to considering a purchase, consider making your own. I've posted some links below.  Based on the low cost heads that are available it may be cheaper to buy one. However, there is a thrill associated with building your own. Note I am not necessarily recommending any particular one of these links nor would I limit you from looking for other plans.

http://www.projectsinmetal.com/free-metalworking-project-plans-adjustable-boring-head-mill/

http://homepage3.nifty.com/amigos/boring_head/boring_head-e.htm

http://home.kleppnett.no/thorhansen/m/BoringHd.pdf

http://www.deansphotographica.com/machining/projects/mill/boring/boring.html

Regardless, happy chips!
Daryl
MN


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## Alittlerusty (May 20, 2015)

Thanks for the replies! Barely have time to wipe the sweat off my face most of the time. So I will be buying one at first , guess I'll try one of the import ones and see if it holds up as King said I can always go big later if necessary.


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## kingmt01 (May 20, 2015)

Are we talking hard bushings or soft bushings? For hard you will need the carbide anyways. For soft you should be able to use a hand reamer & HF has those for cheap. I've been eyeing them for a few years.

Warning with the boring head. I calulated the spindle speed fo the hole sive I was boring & probably not more then .02" in the hole it started screaming like it was going to fly apart. I guess these need turned much sloer because of the offset rocking the machine. IDK


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## Alittlerusty (May 20, 2015)

I will be buying hardened greasable bushings but will be resizing the bores they sit in for a press fit.i don't think the bores are hardened just the bushings are.kubota makes theirs an odd size so u have to buy from them.


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## Alittlerusty (May 20, 2015)

I've never used one yet but I'll definitely let it spin slooow.


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## kingmt01 (May 20, 2015)

Oh. I read it as you were boring the bushings. Your boring before pressing the bushings in.

How many do you have to do. Are they going to fit in your mill?


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## Alittlerusty (May 20, 2015)

I've got about 20 to do but will be doing 4-6 at first on the worst ones. The machine is tiny ( will fit thru a 3 foot door). The stick or arm is only 3 feet long or so and the boom is maybe 5 feet long. Pretty sure I can get either on the mill.


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## Alittlerusty (May 20, 2015)

My mill is a t- head bridgeport so I can slide the head left or right but there isn't any nod on the machine


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## Alittlerusty (May 20, 2015)

Will be abit b4 i start this job and hopefully i figure out how to post picks by then


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## kingmt01 (May 20, 2015)

Depends on where the pictures are at. Most sites want you to host your pictures somewhere else like Picturebucket or somewhere. You should be able to click that icon that looks like mountain & sun to enter the url where the picture is stored. Or you can use embeded code from the site & just copy & past that into the box your typing at what ever point you want the picture to show. If your doing full images I'd suggest hitting enter/return before pasting the hotlink & again after to keep the format a little nicer.


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## pineyfolks (May 20, 2015)

Holes can be bored by making a boring bar and simply sliding the tool out taking measurements from the tool tip to the bar. I have different sets made up that I run through in a series, just switching bars and keep one set for the finish size. I still use them today even though I have boring heads.


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## 18w (May 20, 2015)

A mid priced boring head can be had through Enco when they have a sale. APT is mid level and price.  It is not a bad boring head but not at the level of say a Criterion. I have no experience with the cheap Asian brands. Just be sure and try and find one that the adjustment is direct reading. Also the typical cheap boring bars will cause you grief. Look at Borite bars or HSS or Cobalt bars. Better to spend your money on good quality bars, even if you only buy one at a time.A 2" boring head will do a lot of tasks and is a bit cheaper than the 3". The question is how deep are the bushing bores? A 2" head uses 1/2" boring bars while a 3" uses 3/4" bars typically, although a 3" Bridgeport head uses 5/8". The 1/2" bars limit your depth of cut without fighting flex.
 A lot of equipment manufactures offer hardened bushings with seemingly odd bores. If you are using new hardened or chrome pins, make sure your new bushing I.D.s will be the correct dia. after allowance for press fits. You do not want to have to bore those hardened bushings. You can get by with some honing but when they say hardened they are not joking. This apples to OEM heavy equipment bushings. YMMV.

Darrell


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## Andre (May 20, 2015)

I made one, but then got a lathe...... (easier for me to bore on a lathe...)


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## gwade (May 21, 2015)

I went through the same thought process when looking for a boring head for my Bridgeport Mill.  I elected to get a used criterion head on eBay and then a borite ½" boring bar kit with inserts (IB-500) from Kahn Tools. No complaints and I would do it again.


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## Doubleeboy (May 21, 2015)

I always wondered why my boring bars screamed like a banshee until I read in a book about grinding extra relief on your boring bar tools.  What a difference, so if using hi speed steel or brazed carbide, give your self some more relief , like about 5-10 degrees more relief than the bar came with.  Cheap Chinese boring heads suck, plain and simple, ya you can use them, but the screws are junk, they are not direct reading, basically a kit that will always remind you that you were penny wise and pound foolish.  Get a Wohlhaupter or Criterion and cry once.   Enco in the old days had some nice Enco branded heads that were made in USA and also  France, the french one has the auto facing feature, they both show up on ebay from time to time.

michael


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## kingmt01 (May 21, 2015)

I think I was just insulted & called foolish. Lol

I don't mind my boring tool. If I bought the high dollar tooling is only have a tool or two & couldn't use it because I couldn't afford the other tools to go with it or even the material to make anything out of. I'll make my own boring head & bars later. I'm already working on my own tooling instead of buying. Even "the cheap stuff" isn't cheap.


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## rick9345 (May 22, 2015)

I was just counting I have 7 of them. 
Tool junkie,never enough.


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## mainspring (May 25, 2015)

rick9345 said:


> I was just counting I have 7 of them.
> Tool junkie,never enough.


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## mainspring (May 25, 2015)

Gents,

    I've used Criterion for 45 years and never had a problem. I also use the chinese carbide boring
     bars as they are adequate for most things. For hardened work i use the Micro 100 bars.
     Good tools last a lifetime.......


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## GarageGuy (May 31, 2015)

I have 2" and 3" import boring heads from CDCO.  The shanks are separate, so I bought MT2 and MT3 shanks that I can interchange between them so either can be used on all of my machines.  They are low cost, but sturdy and reliable.

I think the most important part of the boring head is the cutter.  I haven't had much luck with the cheap brazed carbide boring bars... they seem to be hit and miss as far as durability goes.  I bought a nice little indexed carbide boring bar from Shars for a specific boring job, and it works great.  

CDCO, Shars, and many others all carry the exact same boring heads.  I would save money on the boring head, and spend it on the cutting tool.  An import boring head with an Iscar, Walter, or (insert your favorite insert here) is a good usable tool.  Just my $.02

GG


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## ezduzit (May 31, 2015)

Just recently I did my first project on my ancient Index mill. One of the few pieces of tooling that came with it was an early Criterion square bodied, offset boring head, which only goes to 1-1/2" dia, and I needed >2". So I have ordered a (supposedly) NOS 3" offset boring head by Mesa Tools. For both heads I've ordered stubby and short, brazed carbide-tip bars by Criterion and Borite, to start.


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## Alittlerusty (May 31, 2015)

Picked up a used wohlhaupter upa-3 today so just need some boring bars  now


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