Can one buy pliers with parallel jaws that lock like mol

Hi John, putting the locking mechanism aside, I've used many of this type of adjustable spanner very many times in various sizes in my day jobs and have only ever experienced one failure many years ago (apart from wear through use) and that was on the moving jaw, shown by the red line in the photo below. This failure was probably due to a flaw, as no extension tubes etc. were ever used on that spanner and a replacement jaw was fitted, and I still have and use this spanner. Further more, I think you will find the major moments of force on these types of spanners, are shown by the blue and green arrows, so beefing up the area you suggest will probably gain very little more strength. Many manufacturers have been designing and producing this type of spanner all my working life (locking mechanism excluded) and are a very successful tool (cheap versions not counted) I think the main principal of the locking mechanism is for locking the jaw at the desired width so that when in use, the adjusting screw doesn't unwind, which happens to the best of them when used, during putting on and taking off a nut on an adjuster, for example.

Regards Nick.

ChrisB - Laugh all you like.... Then read the reviews of some actual customers:

1. "When I first got my hands on this tool I thought it'd soon become my favourite spanner to have around as the locking function eliminates the inherent flaws with adjustable spanners, and it would also be excellent for gripping stubborn bolts on my old car.
Unfortunately after attempting to loosen one particularly stuck bolt one of the pins in the linkage deformed and now it's nearly useless. Seems that it's fallen for the Stanley tools staple of poor manufacturing quality and cheap materials."

2. "With so much steel, I would have thought "solid". No. Mine arrived, I unlocked the mechanism, and it did not lock back again, ever. Lots of steel, yet, weak. Furthermore, there was no indication of the steel type (not Chrome Vanadium steel, then)."

3. "The disadvantage of an adjustable wrench is that it is not stable enough, so that it may slip around a bolt or nut, resulting in damages to the parts or even to the operator. This item has been designed based on an intelligent idea, locking the adjustable jaw in order to solve the problem. Happily ordered one, just when I found it on the Internet. When repairing my bicycle, I used this wrench for the first time and I realized some deformations on its jaws. The applied materials in the tool are of such a low quality that the wrench was damaged by a bolt under a moderate torque. It is really disappointing. I do not recommend it at all, if you are looking for a durable wrench."


So the above is evidence that all my instincts are absolutely correct.
I am curious enough that I may possibly buy one anyway, but I'm not exactly rushing...

@ Nicholas - It is clear from the design that in use, a huge about of force will now be being taken by the locking mechanism itself. i.e. The jaws will start with a large amount of force due the jaws being locked together, before the additional force caused by the user turning the wrench (i.e. to move say a nut or similar).

The good thing about a Mole wrench is that it is fully adjustable. So if you really force something and end up bending the jaws slightly, you will barely notice because you can just wind in the adjustor thread as much as is required.

However as other reviews have pointed out it isn't all that difficult to bend the mechanism slightly and once that happens the locking mechanism will no longer lock!
 

Edited By John Smith 47 on 26/05/2021 11:19:24

How about one of these old style wrenches with a fine enough pitch thread that you don't have to worry about it loosening? A DIY project...

pgk

The theory is good, but I do want something that has an aggressive actual lock. Just moving your thumb over a thread ain't gonna create and very aggressive lock. A super-fine thread either won't lock very hard or will be so fine that it might get stripped!

What you need is one of these. A King Solomon's Miner's Wrench/Hammer. You can hammer the bejillikers out of any rusty nut with the hammer part before undoing it with the toothed jaws that never let go. Can be used as a pipe wrench too. Failing all else, you can hook a hex drive socket up into the ratchet on the handle and use that too. As the wedged toothed jaw section is self tightening it locks on to the job under pressure of rotation. The harder you yank it, the tighter it grips. And made by Proferred for the mining industry so you CANT break it. Four foot of pipe on the handle will not faze it.

Either that or cut the rusty nut off with the oxy torch. Angle grinders work well too.

A clash of cultures! Engineer's shouldn't have 'instincts', and - because engineering is all about compromise, it's unlikely that anything will ever be 'absolutely correct'. Expectation management is always required.

Adjustable spanners are good example of a design compromise. Strength and reliability are reduced in favour of adjustability. Adjustable spanners are a convenience, not best practice. In many workshops adjustable spanners are forbidden, locking or not, because they are so likely to chew up nuts and bolts. Otherwise, useful in their place, but no-one has ever invented one that's entirely trustworthy.

Open ended spanners are better, but they're inferior to ring spanners, and not all ring spanners are equally good. Still much preferred to any adjustable. Engineers generally prefer single purpose to combination tools of any type, because the latter are rarely fully satisfactory. Not many workshops choose Swiss Army knives!

Dave

Personally, I think this guy is a wind-up merchant who's extracting the urine. He has come up with objections for every sensible suggestion made by people on this forum. If he's that desperate and genuine about what he wants, he should design something himself. How about this?

If he replies, there's bound to be something wrong with it.

lol

I really don't know why people bother to get involved with this guy.

Andrew.

So true!

To be honest when this thread came up again after almost a month, I thought he finalised his super unbreakable parallel jaw locking pliers....but he didn't, he came back with reviews to prove us wrong

Yes, it is rather odd, it’s as if he had not read my post at all.

And I thought he was a genius inventor on the brink of a world-changing patent from one of his other threads.

Make it up with a conventional, say m8 thread and I don't believe it's going anyhwere. Want it tougher? Then stick 6 holes around the circumference of a chunkier thumb wheel and use a bar to graunch it tighter. Want it more lockable? Stick a threaded hole in from the side for a locking set screw. Still not strong enough? make the back end of the head with a countersunk sliding hole through to a threaded hole and a selection of bolt lengths and lock it off there as well. Still not secure enough? Extend the thumbwheel thread all the way through the back of the handle and add a nylock.
This is a tool you can make yourself - the pic was pinched from a youtube vid where the guy builds up the handle from 3 layers of plasma-cut sheet brazed together. It could just as easily be make from 3 handcut sheets and soldered or screwed together with whatever additional fancies you want to add - tungsten jaws, hardened threads etc.

I'm out of this thread.

pgk

Edited By pgk pgk on 27/05/2021 07:26:41

I'm thankful for this thread as I got some Knipex AND Maun gripper things for my birthday!

Here's one from way back. I've had it a while and mounted as it is on a ball swivel it's very handy.

It carries UK Patent Nos 776142 and 731736. The tool itself proffesses to be a SPEETOG Plier Clamp and the swiveling base is marked as SPENKLIN Miniclamp manufactured in Horsham Sussex. Fully adjustable via the knurled thumb screw. The Pliers itself is welded onto the ball swivel spigot in a very neat fasion so unless the marriage was carried out by our workshop which is where I acquired it I would suggest that it was manufactured as a complete unit by SPENKLIN.

Googling Spenklin shows a number of the bases with different devices attached and the pliers as a separate unit can be seen here:-

**LINK**

I'm sure if you keep your eyes open for Speetog Plier Clamp on eBay one will come up eventually.

regards Martin

Edited By Martin Kyte on 27/05/2021 12:10:13

Edited By JasonB on 27/05/2021 12:20:53

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Forgive me, Martin ... but I think the first patent number should read 576142 not 776142

MichaelG.

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Edited By Michael Gilligan on 27/05/2021 13:27:21

@SillyOldDuffer - Yes, all design is a balance compromises. In this case I just wanted a 'design compromise' that locks. I already own various ones that don't.

@Anthony Knights -
1. I thought we were having an interesting conversation about tools and engineering, not attacking people's motive. If you don't enjoy the conversation please don't engage in it.

2. That little vice looks interesting. With its sharp edges, it's is obviously hopeless as a hand tool so of no use compared to this thread, however I might have a use for it as an actual vice to fit within a vice. Is it commercially available?

@Andy Cawley - No disrespect, but other users have had other experiences, that's all.
As I have said, the design of Mole vice grips looks like it would cope well with minor damage to the device in a way that the Stanley thing would not.

@pgk pgk - No, I don't have time to make my own tools. I find it extremely interesting to see what tools exist and this thread has certainly helped un-earth some exotic specimens. If exactly what I seek already exists, at a half-reasonable price, and there aren't a number of people screaming that the product is deeply flawed, then I'll buy it immediately. In this can I am about to buy one of the Stanley tools.

General comment:
Nobody is forcing any of you to read this thread!
All your criticisms about me/my motives are worthless.
I repeat: If you don't enjoy the conversation please don't engage in it.

@Martin Kyte - Self-evidently the jaws are closing around a pivot point and as such will not close in a TRUE parallel fashion, (with the result that by definition as you tighten the thing up, either one or the other end of the jaws will be more compressed than the other end). Interesting design, though.

So why do you like the one posted yesterday and the one from the first page of this thread you did not like?

So what? It's a pliers not a precision collet chuck. I defy anyone to close a toolmakers clamp so that it has exactly even pressure both ends of the jaws. The best milling vices hold work tighter at the bottom than the top. However there will be a position in the swinng that is correct and if the tool has been made correctly it will close to parallel. The pivot point is the adjustable bit rather than the swing of the jaws so unlike the mole wrench the jaws stay parallel in the closed position throughout the range of opening. Who cares what the angle is when it's not holding the workpiece. Not done any measurement of error due to moving the pivot point but by eye its not discernable. Solid works it yourself if you want to find out but there will be slop on the pivot by neccessity in any case.

Michael. You are right it's a 5 not a 7. The stamping is a little obscured.

regards Martin

Edited By Martin Kyte on 27/05/2021 15:18:27