Which Rounded Nut/Bolt Remover
 

Looking for a good set of the spiral type nut/bolt extractor sockets for rounded heads.

Seems even the US made ones can break or wear badly on first use. Also the sizing of the small sets tend to have sockets which are supposed to fit both SAE and metric but some of the sockets apparently don't.
The cheap sets from you know where are often cast so poorly that you cant even get them on the ratchet.
Searched for made in Japan and Taiwan but not finding anything.
I'm beginning to think, just get the cheapest and hope for the best.
Prefer the spiral type as opposed to the straight flute type as the former seem to grab better.

Anyone found a set which don't break, are machined properly, don't wear significantly, have a decent range of sizes and which won't break the bank?
Thanks

Re: Which Rounded Nut/Bolt Remover
 

Think I found them.
Traced them back from locally available, re-branded but very expensive, to the manufacturer in Taiwan, Cosda Manufacturing. https://www.cosda.com.tw/1-2-dr-twis...-sd-1030p.html

Manufacturing process: https://www.youtube.com/watch?v=7H-ETs3oq6c&t=7s
They appear to be machined rather than cast.

19 sockets, so even though they state metric, if the head/nut is rounded, it's moot which size will fit so a large range of sizes seems sensible. Most sets are usually only 8 or 10. Use of a hammer would seem to be the answer. And this is where it gets tricky for the cheap/less strong ones, for breakage.
These are made from SNCM 439 with a hardness of HRC 50-53 which I have no idea what that means but it sounds impressive.
Minimum order direct from Cosda on Alibaba with Fedex shipping, is 1 set:
https://www.alibaba.com/product-deta...006464020.html

Re: Which Rounded Nut/Bolt Remover
 

HRC 50-53 = Hardened to Rockwell Scale C 50 to 53.

Domestic kitchen knives are 52 to 54 and will bend rather than break. The professional knives are 56 to 58.

The hardness is measured by how far an indenter goes into the steel with a given force.

Re: Which Rounded Nut/Bolt Remover
 

According to Google HRC 50-53 is relatively soft. However SNCM 439 seems to be quite strong. Coupled with being machined rather than cast, I'm assuming they chose this as the best combination for the intended purpose.

Re: Which Rounded Nut/Bolt Remover
 

I use metrinch sockets and wrenches, they grab the flats and not the corners of nuts and bolts, one size fits many different sizes ! I have metric and us standard sockets and wrenches that stay in my toolbox

Re: Which Rounded Nut/Bolt Remover
 

I have this set: https://www.lowes.com/pd/IRWIN-BOLT-...or-Set/3732937

To tell the truth, I haven't used it yet, but it looks good.

Re: Which Rounded Nut/Bolt Remover
 

The Irwin are made in the US from global components, whatever that means. You might want to wear eye protection. Here being demo'ed. Starts at 8:10
https://www.youtube.com/watch?v=EWLxzuDMuhk

Re: Which Rounded Nut/Bolt Remover
 

My first car was a 1927 Chevy. I was 14 at the time and the first thing I did was to take it apart and paint everything and put it back together. All the bolts in the body were rusted solid and I used a nut breaker to split them or a metal chisel to cut the bolt in half. The nut breaker was a device that gripped the nut and had a sharp point that was pressed into the side of the nut when a bolt on the nut breaker was turned with a wrench. I don't know if they are still made. That was a lifetime ago.

Re: Which Rounded Nut/Bolt Remover
 

Yes they are still made but not very well, at least in my experience. He demonstrates a couple in that video above. I have the Teng set which he tests but it's so beefy, it gets in the way of itself so it can't actually do what it's supposed to do.

Re: Which Rounded Nut/Bolt Remover
 

I have a manual impact wrench that exerts torque when struck with a hammer. Would that be useful or a mistake when used on head bolts/studs?

Re: Which Rounded Nut/Bolt Remover
 

Never tried one but I have tried to remove screws with a manual torque screw remover and have never managed to get a single screw out with it.