Which Stud Extractor

I have one of this type but have never been able to get it to work, always slips. I’ve had much better luck with the eccentric type like this one. I’ve only twisted one stud off, but it went so easily that I think it was ready to go anyhow. Had to weld on a nut to get it out.

Induction heater would be nice, but I think for the number of times I’d use it, overkill. Torch works just fine for applying heat when necessary.
 
I use the collet-type extractor as others have recommended. First I try each stud with a moderate amount of force. 30-50% of them usually come out that way. I then heat the remaining studs with an induction heater for 30-60 seconds, after which I spray penetrating oil at the base. After letting them cool completely, I use sandpaper or a wire wheel to remove all gunk from the middle of the stud where the collet grips it. I then attach the extractor again and I also put vice grips around the base of the stud if there’s room. Then I carefully pull on the extractor and the vice grips simultaneously, very slowly increasing the torque, until the stud starts to move. I then spray with penetrating oil again, then back to the extractor. This has worked every time, knock wood.
 
I then heat the remaining studs with an induction heater for 30-60 seconds

Induction heaters can now be found relatively inexpensively and seem to work very well. Thought about AliExpress, cheap(ish) yes but reviews on Amazon for the same items are mixed...they either fail quickly or work great. Little to no warranty re-dress at Aliexpress, so probably better to buy locally for a bit more. PayPal will only help if it's DOA or not received.

On Model A studs. Starts at 2 mins in: https://www.youtube.com/watch?v=GGn-5VoS-m8
This guy is using a USA made heater (much better quality).
 
What about using jam nuts with lok-tite applied?

The reason I don't do double-nutting (though double-nutting would work as a first-pass method) is my hypothesis that one of the determining factors for whether the stud breaks is the surface area over which the torque is being applied. Using the collet extractor and vise grips on a clean surface means I'm clamping down on a large percentage of the total surface of the stud, whereas if you use double-nutting then all of the force is being applied onto a fraction of the upper threads. It's the same amount of force coming from your wrench either way.

My intuition, which I have no evidence for, is that distributing that torque over the maximum possible area reduces the risk of breakage because the torsion forces within the stud are more evenly distributed across the cross-section of the stud and because it's harder to put off-axis stress on it (i.e., rotating the wrench in a plane that's not quite perpendicular to the stud).

I paid $200 for my Chinese-made induction heater, which is a lot less than the $600 they want for the nice ones, and it works almost as well. It's large and bulky and it takes longer to heat up, but for a hobbyist garage that's fine. Several times I've used it to safely extract studs on friends' engines.
 
Can someone post a link to these heaters, so that we can see what they look like?


From what I found, you can either go for the Vevor brand with some hope of a warranty: they promise 12 months or no brand on Ebay, Amazon or AliExpress (search term is mini induction heater) or the US made ones https://www.theinductor.com/induction-heater-tools/mini-ductor/models

This is on the Vevor AU website, I can't find it on their US site but may be available elsewhere in the US, just make sure it's the 110v version (we are 240v)
https://www.vevor.com.au/magnetic-i...motive-flameless-heat-10-coils-p_010918601085
 
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My comment from 2019

https://www.fordbarn.com/forum/showthread.php?t=264957&highlight=stud+extractor
The extractor WILL mark up the side of the stud, but this is hidden by the head should you re-use the studs.
Joe K

Thanks to you guys, I ordered the Ares that you mention in that post, earlier today.
There are a lot of these type of extractors available but this one is made in Taiwan, looks well finished and seems to be generally well liked. Trouble is, that I had a difficult time finding one, they seem to be out of stock at most places.

Various nut and stud removers put to the test, the Ares comes out well: https://www.youtube.com/watch?v=EWLxzuDMuhk Stud extractors start at 10:55 mins
 
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Off topic, sort of.

My daughter has an induction heating cook top. It heats the pans and not the top of the cook top. Seems to work great and the top keeps clean.
 
Off topic, sort of.

My daughter has an induction heating cook top. It heats the pans and not the top of the cook top. Seems to work great and the top keeps clean.


Unlike oxy or propane, the induction heater seems to only (or mostly) heat the object within the coil not whatever surrounds it. I think this is helpful for removal because it creates a difference in heat between the two. Not an expert but that is what Youtube is telling me.
Clean as much rust off as possible, it will help the conduction.

Also it's apparently not necessary to get the stud or nut red hot, just starting to get that way.
Also, once it's heated, put a little oil or candle wax which will get sucked into the thread helping the release.

Never touch the coil to the object within it or the cover will get damaged and once that happens, if you touch it to the object again with it being bare wire, your heater will apparently fry.
Replacement coils are easily and relatively cheaply available.


That's it, that's all I know!
 
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I use to use Oxy Acetylene torches to heat the studs. Now I use an induction heater by Bolt Buster and the collet remover Bruce listed in his video.

This method works so well, I don't use the torch for this job any longer.
 
Off topic, sort of.

My daughter has an induction heating cook top. It heats the pans and not the top of the cook top. Seems to work great and the top keeps clean.

It won't work with aluminum pots and pans, they must be magnetic.
 
You need to buy an EDM (electrical discharge machining) machine. The run about $100K but you could probably find a used one for less. They are great for removing broken studs. If you don’t anticipate a lot of use for the machine you can go to a shop that has one and have it done. I had two broken studs removed from a Model B engine. It wasn't cheap but when I picked up the engine the studs were gone and the threads looked undamaged.

Charlie Stephens
 
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