Extractor overview (pic heavy)

[garfunkle24]

I see a lot of repeat questions on here regarding broken bolts, extractors etc. For the benefit of the newer guys I thought I'd post up pictures of the various types of extractors (the ones I have any way).

By doing this it will it least help guys know what their choices are and will hopefully create a forum for people's opinions of the various types.

Just to be clear; I hate all extractors. I just hate some less than others.

First and foremost, this is the best extractor known to mankind:


If that doesn't work, most likely you're screwed and none of the following will work either:

Left-hand drill bits:


If you're very lucky and the screw/bolt isn't 'stuck' you may get it out with just a LH drill bit. Most of the extractors below require a hole to be drilled anyway. Drill it backwards and you might just get lucky! These are Mac cobalt bits, but you have a ton of choices in this area.

Long spiral:


My most hated variety of extractor. Note the gaps in the set....they're there for a reason....These ones are Hanson/Irwin.

Short spiral:


These aren't too bad IMHO. These ones are labelled Mac, but are made by a different OEM and sold through Mac, Snap-on etc

Square taper:


These are joint personal favourites, along with my Rennsteig "cross-taper type" (I just made that term up). These are Proto, but I have seen them labelled as Armstrong and others. Snap-on also makes some similar ones with a twist in the end and they work equally well IMHO.

Cross taper:


These are made by Rennsteig and I've had very good luck with them. Unlike the Protos above, these work in both directions.

Screw-type:


I just recently got these from Wurth. As I haven't used them yet I can't comment on their functionality.

Spline-type:




These are middle-of-the-road for me, functionality wise. I don't use the extractors much anymore, but the drill guides from the set get a lot of use. These are sold as Blue-Point through Snap-on. I'm not sure if they're sold through anyone else.

Hex extractors:



These are basically a tapered (beat it in) type extractor for stripped out hex (allen) head screws/bolts. They have worked great for me.

Screw or "Grab-it" type extractors:

These are sold through many common hardware stores; Canadian Tire, Sears, HD, Lowes etc. I bought them when I was stuck on the road somewhere. Just needed them for some woodscrews with stripped phillips heads. Not sure how well they work on anything beyond that.

External extractors:


These ones are Snap-ons but I've also seen Mac, Proto, Lisle etc. Unlike some re-labelled stuff, I know these aren't all created equal. My Snap-ons have been good, YMMV. Of course on external applications, you have a lot more options (vise-grips, welder, stud puller) before you need an extractor.

External extractors (2):
I just found another type of external extractor from Lisle, part#19250:

http://www.lislecorp.com/divisions/products/?product=67
I have no experience with these.

I don't keep up with external extractors so much as a I rarely need them and when I do, they typically work very well.

Well guys, that's all the extractors I have lying around here. Anybody who has pics of different types, please post them up for all to see.

 

[stricht8]

you have an awful lot of extractors for an extractor hater! Thanks. Very informative.

 

[garfunkle24]

you have an awful lot of extractors for an extractor hater!

Yes I do. I work out in the field a lot where I don't have any access to a welder. Because of this I've tried every kind I've ever come across and hence my hatred of all of them....

 

[Bull]

I like this. It would be even more awesome to show them in action.

 

[jeepnut24]

Nice, this needs to be added to the hall of fame threads in the sticky.... Plus some demo on using the welder to get the job done.

 

[Bull]

Nice, this needs to be added to the hall of fame threads in the sticky.... Plus some demo on using the welder to get the job done.

If he adds some "how to" stuff for the extractor noobs like me, I will add it to the HOF sticky.

 

[DHCrocks]

how does that square taper one work? is it just a matter of pounding that in with a BFH. They look huge, what size bolts would you use that on?

 

[hammergodthor]

I see a lot of repeat questions on here regarding broken bolts, extractors etc. For the benefit of the newer guys I thought I'd post up pictures of the various types of extractors (the ones I have any way).

By doing this it will it least help guys know what their choices are and will hopefully create a forum for people's opinions of the various types.

Just to be clear; I hate all extractors. I just hate some less than others.


Cross taper:


These are made by Rennsteig and I've had very good luck with them. Unlike the Protos above, these work in both directions.


Well guys, that's all the extractors I have lying around here. Anybody who has pics of different types, please post them up for all to see.

Where did you get those Rennsteig's? Their website isn't much help.

Rennsteig.US:

http://www.rennsteig.us/products-overview/usa-special/205-double-edged-screw-extractors.html

 

[hammergodthor]

HaHa, nevermind. D'OH!

Amazon:


http://www.amazon.com/Rennsteig-RNSE5-Screw-Extractor-5-Piece/dp/B001DZ6YR4

 

[BanjoSavesTheDay]

Great idea for a thread! I've always wondered about the different kinds of extractors. Thanks for the information!

 

[arkangel06]

Everone look at those chinese mac tools!!!


Man you really do have alot of extractors do you even use all of them?

 

[garfunkle24]

how does that square taper one work? is it just a matter of pounding that in with a BFH. They look huge, what size bolts would you use that on?

Please see attached shoddy picture to give you an idea of the cross-section of that extractor:

The taper helps it 'bite', but also, as with all tapered extractors, can work against you. The harder you beat them in, the more they expand the bolt into the housing/flange/whatever.

Everone look at those chinese mac tools!!!


Man you really do have alot of extractors do you even use all of them?

Use them all? No. Tried them all? Yes.

 

[Monte]

nice writeup !!!!

but you forgot these:

a Torx bit
e.g. to hammer them into damaged cross head screws

 

[garfunkle24]

nice writeup !!!!

but you forgot these:

a Torx bit
e.g. to hammer them into damaged cross head screws

Actually I did think of Torx sockets! I just decided to stick with the 'intended use' options. When I've had to get ghetto I've used them on stripped hex screw, but good to know they work for cross head screws too!

 

[garfunkle24]

If he adds some "how to" stuff for the extractor noobs like me, I will add it to the HOF sticky.

I will happily add more to this thread and expand it's scope. I am very busy though, so it may be a little....episodic.

I am a little wary though of doing the "how-to guides". Seems it often descends into a ******* match of people's time-proven/infallible/pure-frickin-magic techniques that were bestowed on them by some genius old mechanic, of a kind no longer found....

 

[joenero]

So I'm not the only one that beats torx bits into stripped screws because they're right there and convenient

 

[garfunkle24]

Here are my 5 hot extractor tips:

1. Extractors are hard!

This means that when you break it off (if you use them, you will) you're more screwed than you were to start with. At this point you can probably go on any garage forum, share your woe and receive genuine sympathy without fearing the wrath of even the repetition police.

Now begin researching the properties of diamond, cobalt, carbide......

This is probably a good time to mention that once mechanical means have been exhausted, there are alternative options, including EDM machines. So all hope is not lost!

The subject of extracting extractors is a whole other topic that will have to wait for another day

2. Tapered extractors are..........tapered!

Most extractors are of a tapered design. Typically, a hole is drilled down the centre of the broken bolt (or whatever) and then the extractor is tapped gently or beaten savagely (depending who you are) into the hole, providing a positive interference fit and allowing you to turn the bolt out.

You should, however, keep in mind that this further expands the broken bolt into the work piece, making it even tighter to get out. You should tap it in as lightly as is necessary for the extractor to "bite" when you turn the fastener. You don't have to beat them in so hard if you buy some.......

3. Tap sockets!

Because most extractors are of a tapered/wedge design, they will try and "cam-out" when you turn the fastener. By using a ratchet and tap socket, rather than a wrench, you can apply an axial load at the same time as turning the fastener. Here's a link for those not familiar: http://www.lislecorp.com/divisions/products/?product=398

4. Drill a good hole!

When working on a tough extraction, it is very important to get a well centered hole. How well centered the hole is directly limits the size of the extractor you can use in relation to the work piece.

For example, if you are drilling an 8mm bolt out: If you have the hole centered, you can pretty much drill a 7mm hole no problem, leaving 0.5mm on all sides. If you are off 1mm to one side, you can now only drill a 5mm hole, leaving 0.5mm clearance on the closest side.

You want to use the biggest extractor possible. One of the fundemental flaws of 'internal' extractors is that the extractor is inherently narrower than whatever it is removing...

Of course once you have a good centre, keeping the drill square is the hard part. This is where a drill press/mill on small componants and mag drills on everything else come in.

5. Extractors are not the whole solution.

TV commercials and tool catalogs like to imply that their extractor is a one-stop solution to your problem. They aren't. IMHO, extractors already have a pitiful success/failure ratio, but it would be much worse if I was trying to use them alone.

Extractors are just a small part of the solution to your PITA extraction scenario. I will talk about these more later (if you'll put up with it) but just as a primer, the 3 other most important things needed for a successful extraction are:
1. Heat
2. Vibration
3. Penetrants

 

[Danglerb]

Friend of mine likes a tile cutter bit on a dremel. A little slow, but you basically remove the bolt from the inside out until the threads start to show, then use a pick and it peels right out.

I'd like to see how a disintigrator works too.

 

[garfunkle24]

Friend of mine likes a tile cutter bit on a dremel. A little slow, but you basically remove the bolt from the inside out until the threads start to show, then use a pick and it peels right out.

I'd like to see how a disintigrator works too.

Disintigrator would be sweet! A small, hanhheld unit that runs off AA's lol

 

[Mickey O]

The square tapers are the best in my experience, I have Proto (recently picked up 2 sets for $3) and Craftsman, not sure if Craftsman still has them but they used to warranty them when you broke them.

 

[Teken]

Here are my 5 hot extractor tips:

1. Extractors are hard!

This means that when you break it off (if you use them, you will) you're more screwed than you were to start with. At this point you can probably go on any garage forum, share your woe and receive genuine sympathy without fearing the wrath of even the repetition police.

Now begin researching the properties of diamond, cobalt, carbide......

This is probably a good time to mention that once mechanical means have been exhausted, there are alternative options, including EDM machines. So all hope is not lost!

The subject of extracting extractors is a whole other topic that will have to wait for another day

2. Tapered extractors are..........tapered!

Most extractors are of a tapered design. Typically, a hole is drilled down the centre of the broken bolt (or whatever) and then the extractor is tapped gently or beaten savagely (depending who you are) into the hole, providing a positive interference fit and allowing you to turn the bolt out.

You should, however, keep in mind that this further expands the broken bolt into the work piece, making it even tighter to get out. You should tap it in as lightly as is necessary for the extractor to "bite" when you turn the fastener. You don't have to beat them in so hard if you buy some.......

3. Tap sockets!

Because most extractors are of a tapered/wedge design, they will try and "cam-out" when you turn the fastener. By using a ratchet and tap socket, rather than a wrench, you can apply an axial load at the same time as turning the fastener. Here's a link for those not familiar: http://www.lislecorp.com/divisions/products/?product=398

4. Drill a good hole!

When working on a tough extraction, it is very important to get a well centered hole. How well centered the hole is directly limits the size of the extractor you can use in relation to the work piece.

For example, if you are drilling an 8mm bolt out: If you have the hole centered, you can pretty much drill a 7mm hole no problem, leaving 0.5mm on all sides. If you are off 1mm to one side, you can now only drill a 5mm hole, leaving 0.5mm clearance on the closest side.

You want to use the biggest extractor possible. One of the fundemental flaws of 'internal' extractors is that the extractor is inherently narrower than whatever it is removing...

Of course once you have a good centre, keeping the drill square is the hard part. This is where a drill press/mill on small componants and mag drills on everything else come in.

5. Extractors are not the whole solution.

TV commercials and tool catalogs like to imply that their extractor is a one-stop solution to your problem. They aren't. IMHO, extractors already have a pitiful success/failure ratio, but it would be much worse if I was trying to use them alone.

Extractors are just a small part of the solution to your PITA extraction scenario. I will talk about these more later (if you'll put up with it) but just as a primer, the 3 other most important things needed for a successful extraction are:
1. Heat
2. Vibration
3. Penetrants

That was a fantastic write up, loved the humor also!

 

[garfunkle24]

That was a fantastic write up, loved the humor also!

Thank you vrery much for the kind words!

NB What would you guys like me to cover next???

 

[garfunkle24]

Heat

In simple, general terms, heat makes things bigger. For example it is typical for a ring gear to be baked in an oven before being installed on a flywheel. Once the ring gear cools it is a press fit.

There are several techniques using heat to help in the extraction process:

Thermal Shocking

This is where you heat the whole boken bolt and attached part through several very rapid heat cycles. The idea is that because the two materials expand and contract at different rates, this helps break the bond between them. Quenching with water is usually fine, or you could even use this stuff on the bolt:
http://loctitefreezeandrelease.com/

Thermal Expansion/differential

This is based on heating up one piece creating thermal expansion (eg a housing) so it less tightly grips the broken off bolt etc. For this you will typically be heating an external piece to release an internal piece. This is also true for pins, bushinngs etc..

You want to keep the internal piece as cool as possible.

Now I have a question for the physics gurus:

The pictures are of a pulley on a shaft. I commonly use heat to help pull these off. Now in the first picture, I can understand how the heat expansion (red arrows) make the pulley come off easier. However, if the pulley expands in all directions, why doesn't the centre expand outwards too (into the shaft, grabbing it tighter)? This is shown in the second picture.

What am I missing?: A is shaft, B is pulley.

NB:Loctite has a product called "Freeze and Release". It is basically a supercold liquid in spray form. You could, for example, spray a bolt with it and it would shrink away from the housing making it easier to remove.

 

[tatra]

i have used the fluted style myself with the most success...........course a mig is my first choice...........if not available, i tend to take a break before i attempt an extraction..........going at it pissed off just compounds the problem.........and the centering is paramount.........good write up........

 

[Arne73]

Any pic of tap extractors?
I broke a tap off the other day, another mechanic had a set that saved a lot of time.

 

[Monte]

The "Spline" type seems to be popular over here:

"Belzer"

"Hazet"

"Kukko"

"Gedore"

"Stahlwille"

The "Wiha" ones look like the "Hex extractor" type

 

[Shadowdog500]

Ive had some luck with these collet type extractors. Bought mine off of a Mac truck about 10 years ago.

Chris

 

[woody 73]

Garfunkle Hi,

Very nice job,I liked seeing all the sets. Over the many years I received my best education from an older neighbor who was a very successful automotive engineer,(at the time he went back to law school).

To make a long story short he would fire up his small torch,hit the offending screw till it got cherry red,then he would work his magic! I don't think that man ever met a screw that he could not break free.

Well you did a very nice job! keep them coming.

Woody.

 

[lilredex]

Thanks to all for the informative write-up.

I too have had the best results with the tapered square type of extractor.

If possible take the time to make a drill guide to get your hole centered. A piece of 1/4" plate (or thicker) with the guide hole centered over the stud and anchored using adjacent tapped holes. Try to use a guide hole that is close in dia. to your stud dia., that way you can see that it is perfectly centered. Use a "center drill" to get the hole started, and centered. Those are the ones that come with the big fat body and the reduced size drill on the end, normally used in a lathe. They come in various body diameters.

Have also seen guys take a torch and cut out the stud...........just leaving the threads to clean up. But that one takes real talent!

 

[64merc]

Are the drill bits that come with the "spline" type extractors and guides left hand?

I think I actually have a partial set of those somewhere...

 

[dede2897234]

The "Spline" type seems to be popular over here:

"Belzer"

"Hazet"

"Kukko"

"Gedore"

"Stahlwille"

The "Wiha" ones look like the "Hex extractor" type

Monte,

How do you like using the Belzer "spline" type extractor set?

Are they the most effective bolt extractors you own or used?

If not, which bolt extractor type is the best you have used in automotive work?


Thanks,

Dave

 

[garfunkle24]

Any pic of tap extractors?
I broke a tap off the other day, another mechanic had a set that saved a lot of time.

This is one of the better quality tap extractors, it is made by Walton:

http://www.waltontools.com/products/extractr.htm

To be honest, I haven't found tap extractors to be very useful. If you broke a tap off, it's for a reason. Usually accidently bottoming out or otherwise hitting something in the hole (welding slag etc) means the tap is stuck in there pretty good. In my experience tap extractors cannot exert enough torque to remove a tap in this situation.

Broken tap removal shares a lot with broken extractor removal and I had planned on talking about both later in this thread.

 

[gorgbroza]

Heat

However, if the pulley expands in all directions, why doesn't the centre expand outwards too (into the shaft, grabbing it tighter)? This is shown in the second picture.

What am I missing?: A is shaft, B is pulley.

A wire gets longer when you heat it. Now bend this wire into a circle... the wire gets longer, so the circle expands. Now imagine the pulley as a bunch of concentric circles of different diameters... each one expands and grows in diameter.

 

[rsanter]

I have used the trick of welding a nut onto the top of a broken bolt and then backing it out.
I think its partly the applied heat that helps.

sometimes you cant do this so you have to drill.
the worst. what I think is the worst extractors is the long spirialed, screw type extractors. my experience says they are junk.

if you are going to drill, for sure use a left hand drill bit. over half the time I have had to drill, the left hand bit had backed the bolt out without the need for an extractor.
this is generally true for a bolt that was sheared or overtightened. if its rusted in this is not as likely to work.

I have used the square tapered extractors with some fair luck. they are my preferred ones to use. I also like the short spiraled ones as they have worked for me as well


external extractors
I have the sears set and they have been completely worth their money. I have used them on rusted, rounded off and chewed up bolt heads. have yet to have one not work for me.
I have not tried these on broken off fasteners

bob

 

[Monte]

Monte,

How do you like using the Belzer "spline" type extractor set?

Are they the most effective bolt extractors you own or used?

If not, which bolt extractor type is the best you have used in automotive work?


Thanks,

Dave

Hey Dave,
until now i only used the screw type extractor (1 broke off...), pliers, welder and Torx bit as well as drilling out the complete screw. No hands-on experience with the spline type. I bought it because i got it for just 10.- €. Maybe later this year i can tell you something !

It depends on the broken bolt/screw which is the best method. A small, soft crosshead screw can be removed with a Torx bit where the splines of the bit can cut into the screw, on harder bolts this is not possible (grade 10 or 12 etc.) so the spline type with a prior drill hole might work. On a exhaust system heat could be used e.g. so a heated exhaust flange and a pair of pliers might work or a welded on nut. A stud puller might work sometimes too. But heat cannot always be used. So it´s the best to have several options. A welder, oxy torch, and extractors like the "spline type" or the Facom type makes the most sense imho. Conical "screw type" extractors can widen the bolt and press the bolt into the thread make it harder to remove and can cause the extractor to break.
So i would try out the spline type and/or the Facom type.

Facom drill bit

Facom extractor

or try these out: Schröder "Hi-Trac" with extra cutting edge. (in combination with the Facom drill bit)

 

[scbird94]

i just bought thouse rennsteig extractors- thanks for the heads up they look beefy

 

[Tom2]

I've spent so much time on broken bolts.

What I've learned:

The screw type extracters are pointless. They will break on anything that requires more than a couple pounds of torque to remove (which is going to be any broken bolt).

The spiral type are slightly better..

I have had much better luck with the square type. I have a set from Pepboys. I use the largest one all of the time to remove broken spark plugs. I've put TONS of torque on it. Never broke it - always worked. Same with the medium sized one. The small ones will likely break on anything with more than several pounds of torque. If I see the extractor start to twist - It's time to stop and do something different (usually just drill it out and helicoil). The Pepboys close to me has quite a good selection of helicoils. About $20-$30 for each set. Just use the correct size drill bit, and a sharp bit..Only takes a few minutes to do, and you have a good quality repair.


I also have a set of the external type extractors for rounded bolts or broken bolts sticking out. If the bolt is sticking out, I use WD40 + a propane torch + vice grips.

The external extractors I have are Craftsman. I think the set was around $20. They work really well. I actually just used one the other night to remove a severely rounded and overtoqued motorcycle filter bolt. Worked perfectly.

Also, as mentioned, welding a nut on is great. I've done that before with success - but currently don't have a welder.


Hadn't seen some of the other types listed. Great tutorial.

 

[jeepnut24]

The 1/8" carbide bit I got for my Dremel ATE through the broken extractor like butter....

 

[metal1313]

one question about the spline type. after you've gotten the broken bolt out, how do you extract the extractor from the bolt?

 

[Tom2]

That happens to me all the time.. I use a cut-off wheel on a dremel to cut off the bolt.