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View Full Version : Any machinists in here?



yohinan
01-31-2007, 12:32 PM
I am looking for some specific drill bits. I have found one company that sells them and I trying to poll the collective to see if there are any other makers of these drill bits that offer them at a bit cheaper prices.

Here are the details.

Right Hand Drill Bits
Carbide Tipped
145 degree negative tip

If you havent figured it out these are for drilling into broken easy out's. The easy out's were obviously being used to remove a broken stud/bolt unsuccessfully. The prices I have been quoted start at about 40.00 and go up from there. That is per bit. TIA

Gaslight
01-31-2007, 01:12 PM
Is the material aluminum that broken tools are in?

Jake

yohinan
01-31-2007, 01:18 PM
I am not buying this for a specific project. I am buying them for when they are needed. Could be aluminum, iron, SS, mild steel, etc...

Gaslight
01-31-2007, 01:25 PM
Got ya. Never had a need to go that direction. Sorry no info here.

Jake

pav8427
01-31-2007, 03:56 PM
I've had pretty good luck w/carbide masonary bits. There cheap and available almost anywhere in town.

Doug

B Schein
01-31-2007, 07:23 PM
I have removed more sheered, cross thread, bottom out twist off bolts that I care to remember and only every broken I easy out. That’s because I rarely use them they suck. Easy outs are hardened fist of all this makes them very brittle and easy to break. You also have to take a look at what you are doing with an easy out. This is a left handed tool which you are spinning into a right handed bolt that is broken with the hope that it will grip the broken bolt and back it out. The easy out itself is tapered and you are spinning it into a hole that you have drilled in a broken bolt, but when you do this the easy out is effetely acting as a wedge and making it harder to remove the broken bolt. When you do brake an easy out (I have removed lots of easy outs other people have broke that they have then brougth to my shop) its normally is a very rough uneven surface. Now if you are going to try and drill out a broken easy out with a carbide drill bit in a had drill you will probably chip the drill bit almost immediately, it will just walk of the easy out into the softer parent material. I have removed easy out with a carbide end mill in milling machine. But normally I just burn them out with a ram EDM. When in comes to removing broken bolts you need to take a look at what you working on and why it has broken. If it broke because it rusty I usually just drill them out. If they were bottom out I have had grate success with a spline style bolt removal set. The only time I will even attempt to use an easy out is a bolt that has been sheared off, but in that case I usually just try a left handed drill first that normally will back a sheared of bolt right out.

Sorry I don’t know any places to buy carbide drill bits cheap I just though I would share my though and experience with broken bolt removal.

BMF Machine
02-01-2007, 03:07 AM
I am looking for some specific drill bits. I have found one company that sells them and I trying to poll the collective to see if there are any other makers of these drill bits that offer them at a bit cheaper prices.

Here are the details.

Right Hand Drill Bits
Carbide Tipped
145 degree negative tip

If you havent figured it out these are for drilling into broken easy out's. The easy out's were obviously being used to remove a broken stud/bolt unsuccessfully. The prices I have been quoted start at about 40.00 and go up from there. That is per bit. TIA

The drill bits are outragious in price. Plus you need the strength and rigidity of a mill to keep the bits from shattering and causing more mess! Call some Machine Shops and find one with a hole shooter(they use spark like an EDM) We use one all the time at my day job to remove broken taps, carbide endmills,... etc. It will probably cost ya 40$- any headaches.

Just .02 cents worth

Kevin:smoke:

yohinan
02-01-2007, 09:07 AM
Here is the problem. I understand the cost ratio of sending this work out to someone. But I want to start doing this on a consistent basis in the future. This is not something that I broke and need fixed. Therefore, it would not be feasible to me to send something out everytime someone came in with this problem. 40.00 a pop to pay someone to do this each time equals one of these bits I am talking about. And these bits may at times see use in a hand drill but that would be on rare occasion. They would be used in a drill press or a mill.

Karch
02-06-2007, 09:35 AM
You actually want left hand drill bits, as right hand are standard.

Also, cobalt drills are not cheap, and they should be run at a relatively slow speed, but you should use the chips to tell speed/pressure.

The key is getting the hole started straight and centered. Use a center punch if possible, then start with a centering bit (solid carbide).

68sixspeed
02-08-2007, 07:47 PM
For what it's worth, I bought one of these for work and it's saved my butt a couple times already- it's made for removing broken drills and taps-- I have the whole kit, but they also sell individual sizes. MSC puts it on sale every few months too.

http://www1.mscdirect.com/CGI/NNSRIT?PMCTLG=00&PMAKA=77215606&partnerURL=http://catalogs.shoplocal.com/mscdirect/index.aspx%6Fpagename=shopmain%50circularid=9086%5 0pagenumber=370%50mode=