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td9clyde
11-18-2010, 07:45 AM
how do or can i get a 3/32 drill bit out that is broken off down in the hole?

dirtpusher9
11-18-2010, 08:09 AM
If it isn't to far down in the hole I take something, sometimes my scribe, and drive it down into the bit and break it up. It usally works.

9W Monighan
11-18-2010, 09:01 AM
Can you drill another hole from the other side. The bit will push the broken one out if done carefully.

grumpygrady
11-18-2010, 10:48 AM
what kind of metal is the hole in
if it is alumium you can use acid to dissolve the tap or drill bit

pugs
11-18-2010, 11:44 AM
Drill bits should be fairly easy to get out (taps are a biotch). Like was said try and poke at it with something or possibly even turn the piece upside down and bang it against the bench to get it to fall out.

ihbuilder
11-18-2010, 12:17 PM
what kind of metal is the hole in
if it is alumium you can use acid to dissolve the tap or drill bit

this is a good 1 to try all the hubs I have sitting in the scrap with a broken tap in them :mad:

td9clyde
11-18-2010, 01:09 PM
carbide bit in hot roll steel about 3/16 ths down in the hole can't drill from the other side i am afraid i might break something else off in it it's the roller bolt holes i hate to trash a whole side frame lol

ihbuilder
11-18-2010, 01:33 PM
carbide bit in hot roll steel about 3/16 ths down in the hole can't drill from the other side i am afraid i might break something else off in it it's the roller bolt holes i hate to trash a whole side frame lol

don't trash it for a broken bit . just work at it you should be able to get it out . I know it's frustrating as all heck . heat it if you have to , to expand the steel and bang it upside down on something . If your careful , you can drill from the other side enough to push it out . I've only been trashing my aluminum hubs with broken taps :(

Bodyman
11-18-2010, 02:14 PM
ihbuilder,
they make a tap removal tool. i have one. its has 3 prongs with a band
and it slides in the section of the tap that doesnt have any cutting bits.
steve

pugs
11-18-2010, 02:18 PM
If you had a broken tap or drill in an aluminum part (or brass or other non steel) you can use Alum, aluminum sulfate (dissolved in water) to dissolve the steel and not the aluminum, it's slow going. Nitric acid works faster but is not always easy to come by.

If you have taps or drills that are plugged up with aluminum you can use Red Devil Lye (dissolved in water) to dissolve the aluminum and not harm the tap.

pugs
11-18-2010, 02:30 PM
Being a carbide bit in a steel part I would go with heating the part up. The steel should expand alot more than the carbide, and hopefully then a good whack upside down on a benchtop will send the bit falling out.

ihbuilder
11-18-2010, 04:01 PM
ihbuilder,
they make a tap removal tool. i have one. its has 3 prongs with a band
and it slides in the section of the tap that doesnt have any cutting bits.
steve

I didn't know if they work for 2-56 or smaller

If you had a broken tap or drill in an aluminum part (or brass or other non steel) you can use Alum, aluminum sulfate (dissolved in water) to dissolve the steel and not the aluminum, it's slow going. Nitric acid works faster but is not always easy to come by.

If you have taps or drills that are plugged up with aluminum you can use Red Devil Lye (dissolved in water) to dissolve the aluminum and not harm the tap.

thanks Jeff this is very useful :)

Lil Giants
11-18-2010, 04:32 PM
So what kind of lubrication are you guys using while drilling or tapping?

Local machinist gave me a blue colored liquid (forgot what it was called) that worked great, till I ran out of it. Now I'm using Sulflo cutting oil, which is alright for aluminum cutting/threading, but the blue liquid worked much better.

ihbuilder
11-18-2010, 05:51 PM
So what kind of lubrication are you guys using while drilling or tapping?

Local machinist gave me a blue colored liquid (forgot what it was called) that worked great, till I ran out of it. Now I'm using Sulflo cutting oil, which is alright for aluminum cutting/threading, but the blue liquid worked much better.

Joe ' I use WD 40 , it works well . The reason I brake taps is the same reason I can't take good pics when holding the cam. . I found ATF works great on alum. when turning on the lathe , just gets a little pricey if you have to buy it just for that . Being a self taught machinist I've never herd of the different typs of lubes to use with what metals

Steve

calm n sedated
11-18-2010, 05:59 PM
Clyde, is it full carbide or just carbide tip? If it's a tip and the shaft is hss, grind it or bore a flat surface on the fractured end. Next tap it or just drill a smaller diameter hole with a full carbide bit and lubrication. Now back it out with an extractor. Worse comes to worse you may have enough space to spot weld a rod to the flattend end of the bit or the hole that you drilled into the fractured bit and crank it out.

Iron Art
11-18-2010, 06:20 PM
Clyde, As a last resort, befor starting over, if its one of the verticle holes in the track frame, take a cutoff wheel or grinder and excavate it out, could use a burr, weld up the damage and grind the area smooth or set it up in your mill and finish the repair, redrill and retap. Steel and small taps are not real easy to work with. Fred

fhhhstix
11-18-2010, 06:42 PM
since it is carbide in steel heat the hec out of the steel and the bit till they are both red hot and hit the bit with a punch and hammer the bit should break up and turn mostly to dust carbide becomes real britle when it is heated. I learned this trick from an older gentlman at work.

Travis

td9clyde
11-18-2010, 07:34 PM
thank you all for the great quick responses i picked up a new drill bit and drilled the side and dug it out it was stuck pretty good in there took a lil bit to get it to even move around but when it came loose i got it pushed up and pulled it the rest of the way out with needle nose pliers and yes it is very frusterating when that happens but i kept drilling the rest of the holes and when i got them done i drilled on it and worked it out

grumpygrady
11-19-2010, 08:44 AM
here are a few posts from the anodizing group about broken taps
i hope this helps
my tanks are not set up yet or i would try it and see


I've read that a steel tap that's broken off in a part will dissolve away during
the anodizing process. One of the larger parts I need to anodize does in fact
have a broken 4-40 tap stuck in it, but I don't want to contaminate the
anodizing bath. Can the tap be dissolved just by soaking the part in non-diluted
battery acid? Or is the electrical process of anodizing necessary in order to do
this in a reasonable amount of time?


Re: [anodizing101] Re: Dissolving a Broken Tap


..I have also used the nitric acid to dissolve thread forming taps from aluminum. The stuff I used was a kit called 'Tap-Out' sold in machine tool shops...it had the acid, some clay to build a 'dam' around the top of hole, and some pieces of stainless steel wire, used to agitate the acid every few minutes..
The acid is a mixture of Nitric acid and alcohol...called nitol...it's only about 20-30% acid. You can buy nitric acid at a laboratory chemical store, but it will be a solution of nitol...nitric aid is very corrosive....even at the 20-30%...and cannot be mixed with water as a storage ...
I don't know the why of how it works, but doesn't attack the aluminum to any degree.
Nitol is very slow to dissolve tool steel, which is why it's not usedin machine shops in lieu of EDM....and hole must be sealed at the bottom of course for nitol.


Jack,
I have anodized a bunch of taps out. I have never tried it with just acid. What I would suggest is to setup as small a tank as you can to get the tap out and keep that acid separate from your anodizing bath.
Regards, Ray

grumpygrady
11-19-2010, 08:47 AM
sorry just saw that the tap was in steel
thats what i get for not reaDING EACH POST UNTILL THE END OF THE THREAD LOL

ihbuilder
11-19-2010, 09:39 AM
sorry just saw that the tap was in steel
thats what i get for not reaDING EACH POST UNTILL THE END OF THE THREAD LOL

no you are right , I'm always braking taps in aluminum . mainly 2-56 . I sorta hijacked :o when trying to help Clyde with a broken drill bit in steel . this getting broken taps out of aluminum is a big help . :)

Espeefan
11-19-2010, 04:47 PM
Hi guys. Regarding what oil we all use when tapping smaller holes in aluminum, I've been having really good luck, so far, with Rigid's Nu-Clear thread cutting oil. I've been tapping a lot of 3mm and 2mm holes lately, into aluminum and stainless steel, but and haven't broken or plugged up any of my taps yet. Previous to using the Rigid oil, I tried a few different brands and noticed the smaller taps would plug up a lot sooner and easier in aluminum. I pretty much swear by the Rigid Nu-Clear oil now and will probably stick to it from here on out.

td9clyde
11-19-2010, 07:29 PM
yep i now have a tap broken off in the side frame lol and yes it is a 4/40 lol 45 holes done and the last 3 to go and it snaps lol i am tryin to figure out a way to do this when i get them all tapped out and all the other caps on and bolted down i might even just weld that cap on lol

Espeefan
11-19-2010, 10:29 PM
It figures that you would break a tap on the last couple holes, rather then the first few! If you can't get that tap out, just cut the material away from around the tap, and section it. You can always weld up the oversized hole, replace an entire section of metal, (like a small square) grind it flat, and drill a new hole. That's the beauty of metal working. If you take to much off, or drill to big of a hole, you can almost always fix it up again with a welder.

td9clyde
11-20-2010, 05:28 AM
yea thats what i was thinkin i would have to do lol

td9clyde
11-20-2010, 05:30 AM
no you are right , I'm always braking taps in aluminum . mainly 2-56 . I sorta hijacked :o when trying to help Clyde with a broken drill bit in steel . this getting broken taps out of aluminum is a big help . :)

It's all good we all or at least both of us learned something lol

Izzy
12-01-2010, 05:17 PM
for threading or even cutting soft copper - I was told to use "crisco"

For years they were using animal fats instead of oil based lubricants....

Bodyman
12-01-2010, 10:23 PM
ihbuilder.
regarding the tap removal tool.the smallest my set goes to is 3mm so it most likely
wont work.
steve

Bodyman
12-01-2010, 10:32 PM
i found this site. it has a tap stand. suppose to help keep taps straight
and keep from breaking. i bought one.when i get it ill let you know how it works.
www.LittleMachineShop.com

pugs
12-01-2010, 11:10 PM
Another option is a tapping block. holes sized to just allow taps to slip through, faces are perpendicular to the holes thus holding the taps straight.

This was one of the many tools I had to build back in machine tool school. This one is sized up to 1/2" taps, could easily build a smaller one for the little stuff. I had to make it on a jig borer but I think if you were careful and took your time you could do it on a regular mill as well.
http://i839.photobucket.com/albums/zz317/JPMach/Misc/DSCN0503.jpg
Was made from O-1 and hardened IIRC, but for the small taps you guys are using a softer steel would probably work fine

Izzy
12-03-2010, 07:46 PM
for all those novice types - always use a tap handle - and as a "T" handle, not an "L" unless you have to (tight spot) - using a common wrench will almost always cause trouble......

Lil Giants
12-03-2010, 09:06 PM
I put my 3mm tap in a 7.2v reversable cordless drill, keep the tapp well lubed and clean the tap constantly with a brass brush. Barely pulling the trigger, when it stalls, back it out, clean/relube the tapp, blow out the hole with pressurized air and go again. Haven't broke a tap yet, wore a few of them though.

That tap guide you show Jeff looks to be the cats meow, very simple & effective. :cool:

pugs
12-03-2010, 11:56 PM
The tap guide works great with a cordless drill. Just have to watch out for taps that have shanks larger than the thread portion. I should really build a smaller thinner tap guide for the little taps.