Koken Nut Grip Sockets - Suitable for Daily Use?

[The Critic]

I recently purchased a few 1/4" dr Koken Nut Grip Sockets and are finding them to be more useful than anticipated.

I would like to replace my "daily-use" 3/8" dr standard chrome sockets with a set of Nut Grips.

Are there any concerns with using these sockets for daily use, or should they be reserved for specialty situations? Size range would be 10-22MM, but will most likely be using 10-17MM regularly.

 

[mike93lx]

What kinds of concerns are you thinking of? Are they damaging fasteners?

 

[The Critic]

What kinds of concerns are you thinking of? Are they damaging fasteners?

Socket longevity. Wasn't sure if these sockets are designed to withstand constant use - those retention balls look like a wear item?

 

[toddmorr]

I sure don't use them in every case, that ball can wear and I guess the spring tension could theoretically weaken also but no data to back that up.

On the other hand if there were a legit concern koken would surely mention it, that's just how the Japanese roll

 

[demarpaint]

I consider them a wear item and use them only I need them.

 

[mike93lx]

Koken warranties them like any other socket. I'd have no qualms with using them daily, but if you are worried, why not call koken and get it from the horse's mouth?

 

[Dave455]

The ”nut grip” sockets are seriously useful. I only have them in 3/8” drive, but they excel when you are working with small fasteners so I’ll probably add 1/4” drive at some point.

I don’t generally use them unless I have to, partly because I have other sockets as my first choice, but mainly because the nut grips are harder to clean. If you don’t keep them clean you get dirt and grease mixed with the ball bearings and they don’t work so well.

 

[neophyte]

Oiling the spring and ball would help with longevity, but not completely.

 

[Draftpick1]

think they have repair kits for the nut grip sockets

 

[Draftpick1]

Koken warranties them like any other socket. I'd have no qualms with using them daily, but if you are worried, why not call koken and get it from the horse's mouth?

how many sockets has koken replaced for you?

 

[mike93lx]

how many sockets has koken replaced for you?

Why? Do they deny your warranty claims?

I don't own any koken. Just citing that as a likely indicator of their expectations for life.

 

[The Critic]

Why? Do they deny your warranty claims?

That is my concern. Judging from this thread, their approach is far from the typical "no questions asked" policy of SO and other brands:

Hows Kokens warranty policy?

Broke/cracked my wheel nut socket today. Has been in service about 3 months now. I use them every day, is this the kind of thing Koken would warranty? Or you figure theyd just say the useful life of the product? Before I bounced this off Koken Usa and however much back and forth that would...

www.garagejournal.com

 

[Dave455]

This question of warranty seems to come up regularly.

I have a good deal of KoKen, and I have no doubt that they, or my dealer, would replace any item that had a genuine manufacturing defect.

That is, in effect, an identical warranty to Snap On. The difference is in the interpretation. Snap On generally seem to be prepared to replace any tool that has been broken, or even worn out.

That’s an expectation that’s almost unique to the U.S. and just about unique to Snap On. Of course, if I’m paying three times the price for a Snap On tool than I am for a KoKen tool, I’d probably expect that too.

In probably 20 years of buying KoKen I’ve never had a tool with a defect. Have I worn out or broken any, sure (a couple of hex and torx bit sockets), but they weren’t defective - and spare inserts (effectively a consumable item) were a phone call away.

Given the quality of the tools, I’m happy with KoKen, and I wouldn’t want them to change their business model to one where I’m paying upfront for someone else's breakages!

 

[Pexto]

...
Given the quality of the tools, I’m happy with KoKen, and I wouldn’t want them to change their business model to one where I’m paying upfront for someone else's breakages!

This is exactly how I feel. I purchase tools from companies who I know make quality products. The warranty is secondary.

I use my tools responsibly, and I don't expect companies to replace tools that I abused or wore out. Like Dave455, I don't want to pay for someone else's abusive practices.

Edited to add: I would not use a NutGrip socket to break loose a tight fastener, as I would expect them to be weaker than a standard socket.

 

[Draftpick1]

Why? Do they deny your warranty claims?

I don't own any koken. Just citing that as a likely indicator of their expectations for life.

Not everyone is no questions asked, and you acted like they would so I thought your were knowledgeable and had been through a warranty process with koken

 

[2ndGearRubber]

I believe the nutgrip universals are specifically listed in the catalog to.not be used for breaking free or final torque.

I have used my standard socket style nutgrips for tightening and breaking free, both 3/8 and 1/4. Generally speaking, I would say this is not ideal. Imagine just drilling a hole in two of the flats of a socket, then using that socket as your daily driver. That's essentially what nutgrip is.

 

[Steve_P]

I believe the nutgrip universals are specifically listed in the catalog to.not be used for breaking free or final torque.

I have used my standard socket style nutgrips for tightening and breaking free, both 3/8 and 1/4. Generally speaking, I would say this is not ideal. Imagine just drilling a hole in two of the flats of a socket, then using that socket as your daily driver. That's essentially what nutgrip is.

Yes, this is what I also recall- not for breaking free or final torque. I have the nut grips and use them only when necessary. The problem is more from the spring groove than the hole; the groove reduces the wall thickness at the corners where the stress is high, and the thickness is minimal.
The obsession with warranty here is just crazy. Any tool can be broken if you try hard enough, and expecting it to be replaced is just not realistic- unless you are buying it from a tool truck and paying the 2-3X premium for that up front. Put yourself in the manufacturer's shoes- companies like Koken, Wiha, Knipex.... are pricing items to stay in business, and not marking up to replace every broken or worn-out item like Snap On does.

 

[2ndGearRubber]

Yes, this is what I also recall- not for breaking free or final torque. I have the nut grips and use them only when necessary. The problem is more from the spring groove than the hole; the groove reduces the wall thickness at the corners where the stress is high, and the thickness is minimal.
The obsession with warranty here is just crazy. Any tool can be broken if you try hard enough, and expecting it to be replaced is just not realistic- unless you are buying it from a tool truck and paying the 2-3X premium for that up front. Put yourself in the manufacturer's shoes- companies like Koken, Wiha, Knipex.... are pricing items to stay in business, and not marking up to replace every broken or worn-out item like Snap On does.

I looked through the catalog and the Koken USA website, zero mention of torque limits "meets DIN/ISO standards".

I can't remember which site I read that on. Obviously the design has less metal, and thus less tolerance to use/loads. I just bought a koken 3/8 6 point set for about $60, 8-19mm. Hard to to justify exclusive use of nut-grip only if you can have an extra set of regular sockets that cheap. Now I get the convenience factor of having one set. IMO if you're not cranking on rusty stuff, hammering them onto fasteners, etc you'd be fine using them every day. My 1/4 8mm and 10mm have been used on M12 ratchets and hex drivers a good amount.

 

[threewood]

I have a newer set of these in 3/8" drive and would not hesitate to use them as often as needed. They are very nice to have. The only issue is that if you are removing a nut it will stick in the socket if you take it all the way off. Normal use on a 3/8" drive shouldn't stress them to failure.

 

[tamaraw]

Koken warranties them like any other socket. I'd have no qualms with using them daily, but if you are worried, why not call koken and get it from the horse's mouth?

Good luck with that if you don't speak Japanese.

 

[Jack_K]

Koken do not specify them as being weaker in the catalogue and they usually specify if something is a weaker design.

 

[tamaraw]

Socket longevity. Wasn't sure if these sockets are designed to withstand constant use - those retention balls look like a wear item?

Ball bearings are pretty hard wearing and you wouldn't do much simply sliding stuff in/out. Plus there is no reason you couldn't replace them.

I would be more concerned about sharp/pointy foreign objects snagging the spring (probably not a big deal for most environments) or the socket failing under excessive load since it does have a groove machined around it and those extra holes.

Less of a wearing out issue, more of a limited max force thing, imho.

 

[Zewnten]

I'd think small dirt build up will cause the nut grip to lose tension unless you're good at cleaning the moving parts out every so often.

 

[Black300zx]

Just wanted to chime in and thank the OP for posting this. Not because I can offer any guidance, but because I didn't know these existed and now they're added to my tool wish-list I definitely see myself grabbing for one of these when I need to install/remove a stainless fastener in the bilge of my boat.

 

[turninwrenches396]

I'm just not sold on these sockets yet I fear the spring won't survive long when they get packed full of dirt and corruption id say they may be a useful backup to get a fella out of a jam but 100% not for everyday heavy duty use

 

[dchawk81]

I'm just not sold on these sockets yet I fear the spring won't survive long when they get packed full of dirt and corruption id say they may be a useful backup to get a fella out of a jam but 100% not for everyday heavy duty use

That's what brakleen is for.

I talked to the inventor of brakleen personally and he said yes indeed he had Koken nut grabbing sockets in mind when formulating the product.

If you don't believe me, just ask me.

 

[turninwrenches396]

That's what brakleen is for.

I talked to the inventor of brakleen personally and he said yes indeed he had Koken nut grabbing sockets in mind when formulating the product.

If you don't believe me, just ask me.

Yea at $150 an hour I cant see washing down every bolt before I remove it but thats just me.

 

[dchawk81]

Yea at $150 an hour I cant see washing down every bolt before I remove it but thats just me.

The brakleen is for Koken maintenance, not your nuts.

 

[turninwrenches396]

The brakleen is for Koken maintenance, not your nuts.

Thats less likely to happen...nice tool for a collector not so much a worker

 

[dchawk81]

Thats less likely to happen...nice tool for a collector not so much a worker

Woosh.

 

[Spacey_G]

How many $150 hours have been collectively wasted, I wonder, because of fasteners dropped in unfortunate locations?

 

[dchawk81]

How many $150 hours have been collectively wasted, I wonder, because of fasteners dropped in unfortunate locations?

Billions of dollars for sure. Especially searching for lost 10mms.

 

[turninwrenches396]

How many $150 hours have been collectively wasted, I wonder, because of fasteners dropped in unfortunate locations?

Ohhh no question its a real problem but the koken solution is simply not gonna hold up in the heavy duty world i think they are a great company and have some great tools these sockets just aren't quite the solution thats good long term in my opinion

 

[noid]

There is nothing inherent about the design that will make the spring loose tension over time. It just no where near expands enough to take a set, or otherwise deform.

It is possible the ball will gunk up, but a cleaning once a year should do plenty.

There are a couple other options also available:

Wera:


Tone:

 

[Draftpick1]

There is nothing inherent about the design that will make the spring loose tension over time. It just no where near expands enough to take a set, or otherwise deform.

It is possible the ball will gunk up, but a cleaning once a year should do plenty.

There are a couple other options also available:

Wera:


Tone:

The wera is retention is plastic while I like the double ball I don’t like the plastic and cold and heat effects plastic worse than metal.

 

[Draftpick1]

Ohhh no question its a real problem but the koken solution is simply not gonna hold up in the heavy duty world i think they are a great company and have some great tools these sockets just aren't quite the solution thats good long term in my opinion

Have you used these? We use them regularly mainly 2 sizes for for line work to hold bolts 75’+ in the air, been using them for 3 years now and have not had to replace any yet.

 

[threewood]

Just wanted to chime in and thank the OP for posting this. Not because I can offer any guidance, but because I didn't know these existed and now they're added to my tool wish-list I definitely see myself grabbing for one of these when I need to install/remove a stainless fastener in the bilge of my boat.

So far so good. I'm very happy with this purchase. I use to dip my sockets in grease to get nuts to stay put while I snaked them up behind the dash. Got messy lol

 

[Steve_P]

I looked through the catalog and the Koken USA website, zero mention of torque limits "meets DIN/ISO standards".

I can't remember which site I read that on. Obviously the design has less metal, and thus less tolerance to use/loads. I just bought a koken 3/8 6 point set for about $60, 8-19mm. Hard to to justify exclusive use of nut-grip only if you can have an extra set of regular sockets that cheap. Now I get the convenience factor of having one set. IMO if you're not cranking on rusty stuff, hammering them onto fasteners, etc you'd be fine using them every day. My 1/4 8mm and 10mm have been used on M12 ratchets and hex drivers a good amount.

I'm 99.9% sure that I read somewhere what you said about not for use for breaking free and final torque; there is no way both of us imagined that . It may have been a slip of paper in the package, dunno. Or it may have been on the website 2 years ago and not there now. But anyone that thinks these sockets are as strong as a normal Koken socket needs to look at the pictures above. There is a groove that is cut in the OD of the socket for the spring to rest in. I mentioned this in my original post. This reduces the effective OD, especially at the recessed points - where sockets break. This means it's not as strong as a socket that doesn't have the groove cut into it. You shouldn't need a mechanical engineering degree to recognize this. This doesn't mean you can't use it every day, but it does mean that you shouldn't expect it to be as strong as a normal socket, and you shouldn't expect Koken to warranty it if you break it.

 

[turninwrenches396]

Have you used these? We use them regularly mainly 2 sizes for for line work to hold bolts 75’+ in the air, been using them for 3 years now and have not had to replace any yet.

Have used them yes couple fellas in the shop have them they used them for a while had a few failures they are great for a clean environment but when dirt and corruption is in the picture they have their downfalls again for some applications yes they are great but like anything else have their issues

 

[dchawk81]

I'm 99.9% sure that I read somewhere what you said about not for use for breaking free and final torque; there is no way both of us imagined that . It may have been a slip of paper in the package, dunno. Or it may have been on the website 2 years ago and not there now. But anyone that thinks these sockets are as strong as a normal Koken socket needs to look at the pictures above. There is a groove that is cut in the OD of the socket for the spring to rest in. I mentioned this in my original post. This reduces the effective OD, especially at the recessed points - where sockets break. This means it's not as strong as a socket that doesn't have the groove cut into it. You shouldn't need a mechanical engineering degree to recognize this. This doesn't mean you can't use it every day, but it does mean that you shouldn't expect it to be as strong as a normal socket, and you shouldn't expect Koken to warranty it if you break it.

Aren't they pretty much just for holding the fastener so you can fish it into an awkward location and get it mostly in place before locking it down with a proper socket?