Why so much variation in beam torque wrench handles?

jeejay · Jul 3, 2016

I'm looking around at these "beam types" and some handles tilt, some are ball shaped, some pear shaped, some knurled, some wavy, etc.

I don't know about the tilting ones, especially plastic (they disturb me)...

Otherwise I gather the higher end brands are Sturtevant Richmont, Seekonk, and Tohnichi, while the rest are rebranded or unbranded Chinese variations (or extinct on the market, and they no longer make them without stick on measurements for less than the cost of any other torque wrench, that's the other variation I noticed). Not complaining, just wondering what happened to this statement from the article: "This type of wrench is simple, inherently accurate, and inexpensive".

Anyway I've attempted to order a couple of high capacity ones from China to see if that's infallible...

wholesale-price-BOSI-great-1-2-Dr-socket-torque-wrench-tension-wrench-0-300N-m-BS365330.jpg

Kind of a unique handle on this one... :question:

Yes and no, there are a few alternate colored lookalikes with different brand names (but most are wholesale imports, orange, green, etc). The other one I found with a fixed knurled handle says it's 0-500 newton meters, if that's even possible (3/4" drive though, might be, if they send it to me).

Oh, here's a pic of those types side by side.

TB1kchJLpXXXXXUXVXXXXXXXXXX_!!0-item_pic.jpg

Looking to get one of each to distinguish between them (or maybe I'll start a collection with different colors •••)

pepi · Jul 3, 2016

Nice LOOKing tool but becoming extinct as has the slide ruler.

jeejay · Jul 3, 2016

Yeah (this appears to be), and they seem notoriously difficult to read while pulling down on them (I got a smaller one which was more widely available to try). Now I'm thinking about comparing bigger sizes to verify calibration in a simple way on modern torque equipment (it seems these are used for that too, being inherently accurate, as they say). I just have to be standing over the top of their scale to read them agreeably, and of course it's difficult to torque the small one slowly sideways throughout its range, without moving myself (I suppose some of the handles out there wouldn't help in the matter, or that's just me).

As it were, I'd say they are inherently oxymoronical, accuracy wise as they're peculiar to read (perhaps not so much in a limited fashion by chance). Tohnichi say "although axial tension is really what needs to be controlled and measured, it is very difficult to do so, therefore torque is used as a substitute characteristic for administering and controlling tightening operations". Sort of a novelty still (sounds about impossible to be a torquing purist). Well, I'd imagine back when these were used exclusively, it was a two person operation, one to man the wrench, and one to read its scale straight on (maybe that's what they do with high end ones to date, or have some kind of laser tilted mirror apparatus in place). One was called a "bunker tool", so standing in a pit could do? :headscrat

Treeman · Jul 3, 2016

So, you are ordering some junky Chinese wrenches to see if they are infallible regarding "simple, inherently accurate, and inexpensive". Isn't that what they call an oxymoron?

You are completely wrong about avoiding the pivoting handle style. The top of the line Sturtevant Richmont has the pivot point handle to make sure that the length of the beam is assured. Any solid handle adds even more variability depending where you hold it.

It is already known that the down side of beam wrenches is reading it. I put a piece of electrical tape on the desired reading to help a bit.

You also know that the torque process is +/- 25% accurate to begin with, right? So, debating about 1-5% error from reading the scale is rather moot.

But, to answer your question (in the title), the reason for different handle styles is that the ball and/or pivot styles better guarantee the correct beam length. The solid handles will tend to appear on the cheapest, junkiest ones.

T45 · Jul 3, 2016

"The operator must use caution to apply loads only at the floating handle's pivot point"

The wrench is calibrated in a certain way, so the handle needs to be accurate for length. The 1/4 versions have a ball, but the effect is the same. The 3/8 version has a more proper handle with a pivot so you can effect more purchase. But if it was just a handle, you choke up or down you can (presumably) mess up the way the steel bends and the measurements. :dunno:

T45 · Jul 3, 2016

On a side note, there are many NOS versions around from USA oems. No need to buy chineese imports on this tool. The only time they are a hassle to use for common tasks is if you are working upside down, without a lift for example. For use on motorcycles or bicycles they are quite effective. They have alot of value as a bakcup and a sanity checker even if you have clickers around.

jeejay · Jul 3, 2016

Thanks for explaining about the tilting handle. The one I got without it seems be right on according to two digital adapters I checked (so a Chinese version of a simple beam type isn't necessarily problematic, unless the sticker falls off). Maybe they're hard to hold wrong, as long as you use whatever handle is there (that's wavy by the way), and my regular torque wrench says to torque from the middle of its handle for best accuracy.

What's an NOS version? Would that be like this Proto (looks like one made in China, just a little lower range than those above)... I considered used/antique and smaller Sturtevants (somewhat junky looking, at least the scale was etched), but even those tend to cost more than new so-called junk, or what they might have cost originally (I imagine new metal is in better shape for torquing, come on). The high end ones cost twice as much as my truck torque wrench (which isn't el-cheapo), and still have lower range (about half that).

Anyhow I'm just looking to test this concept for limited use, whereas the costly ones are used for aircraft they say (and don't see how looking at tape from an angle would be much different than the scale for general purpose use, so if torque itself is +/- 25 when lined up, maybe that's +/- 50 when not... or why even use a special wrench, well it's kind of critical for trucks since big wheels fly farthest and cause the most damage if grossly under or overtorqued). To me this is merely like measuring twice with a couple different types of rulers, to be sure I'm looking at the marks correctly when dialing my other wrench in.

jeejay · Jul 5, 2016

Ah, NOS means New-Old Stock. Wouldn't know where to find it though if that's never been offered at retail (seems more obscure than a Chinese website).

ibedayank · Jul 5, 2016

why so many options?... well why are there so many cup sizes to a womens breasts... not everyone likes the same thing.

jeejay · Jul 5, 2016

That's sassay... one is being sold on ebay by someone who offers various wigs for hairstyling practice (and one torque wrench). :headscrat

Packard V8 · Jul 5, 2016

My first torque wrench was a Craftsman round beam and I still have it in the original, somewhat grimy box.

Out in the country, in 1966, the old pros claimed owning a torque wrench meant you hadn't tightened enough bolts "Or you'd know how it's supposed to feel when it's right."

FWIW, the local large engine rebuilder spent big bucks for a computer-controlled torque-ing machine because they can no longer find workers who want to pull 100 lbs/ft all week long.

jack vines

jeejay · Jul 5, 2016

That's neat, I doubt the sticker on mine will last as long (and last time I checked they sell ones with stick on scales too, or don't make them like they used to, or they're made in China). I just find it a little strange that something which was supposedly cheap to manufacture in the first place had to be made that much cheaper by everyone, or extremely expensive. I don't see anything in between like other torque wrenches.

jeejay · Jul 16, 2016

Okay, going back to these, the first one I ordered has arrived, and I'm pretty sure its scale is painted, not a sticker (wouldn't want to scratch it to be 100% certain, or actually there's a miniscule peice of wood embedded in the paint, so now I'm positive). Only problem is, the handle stinks (literally, it's that harbor freight rubber smell from hell)! I thought it looked like nylon/plastic in the picture. Slips right off though, so I'll try to replace that part (with some other type of rubber I guess)...

The other thing is, it's the same length as my 150 foot pound one, but has a 220 foot pound scale (at 300 Nm). Not sure about that, unless I'm doing a handstand. Could be longer, but for what these cost it's pretty good, with thicker steel (should outlast its counterpart with a sketchy scale), and the 3/4 drive wrench with a knurled metal handle would be closer to what I was going for, above and beyond that.

What else? The 13mm (1/2") steel rod extends 3.25" past the scale attachment for that handle to fit over, which is 4" long, and maybe I can extend it for higher torque. No wait, then it wouldn't be very accurate. I guess it's the Bruce Lee model... :ninja:

Gonna have to do some serious kung fu to slo-mo 300 Nm laterally (torque chi).

2oolhound · Jul 16, 2016

As freeman said the pivot ensures the applied force is always at the appropriate distance to produce accurate deflection of the needle. This type is great for setting bearing preload as you can watch the force build up as you approach your settings.

jeejay · Jul 16, 2016

That's good to know, I think gripping the middle of the handle is close enough for what I'm doing with it though. How far off could that possibly be, since the pivot is essentially doing the same in applying pressure there? Not too much... more like an inch-pounds or lower range proposition for that type, I presume.

jeejay · Jul 16, 2016

It's just that no other torque wrench bothers with a pivoting grip. I guess it could be tested by hanging a weight off a rope over different spots on the handle to see what happens along the thing (vs several smaller weights across it at once), I'd just have to use the same number of clamps to keep the rope from sliding, for the sake of sameness (or use smelly rubber straps that don't slide).

This gives me another idea though, I could use a ratchet strap hooked up somehow to torque it higher, while being able to read the scale for other testing (without having to lean into it myself), and if the strap was narrow, that would be a more exact application of pressure than a palm grip, perhaps. In this case you could maybe do more with a fixed handle...

Then again, without getting too involved, I checked it with a digital torque adapter attached, and used a finger in different places, torquing to the 50 Nm line. Seems to agree closest at the end of the handle nearest the scale (in other words, where the handle would start if I had the grip on there). It's really touchy though, I mean the amount it was below 50 from farther back would also spike above it from close up, so, as a rule of thumb, you could go a little past the mark, or not, depending on where you held it, for that to be just as accurate (since it changes every split second while I'm trying to hold it steady). I'd want to use a ratchet strap or something similar for careful work, because a hand applying variable pressure (with or without a pivot point) isn't as exacting, especially at higher torque. I'm sure some of this is due to me using it laterally, but at least it illustrates that your arm alone will potentially eliminate any advantage of the different handle designs (maybe if you hold your breath though, speaking of smelly handles, ah... so that's their angle).

jeejay · Jul 20, 2016

Got the unscented one with a solid handle, now that's the way to go with these. May want to wear gloves with that though, the knurling is very pronounced.

4x4_G30_Sportvan · Jul 20, 2016

I have 2 Craftsman beam types, one is 1/2", the other is 3/8". They work well for me.

jeejay · Jul 20, 2016

That's good. The 3/4 drive chinormous one is only 2" longer for an extra 200 Nm on the scale, so yeah that's another Bruce Lee edition.

jeejay · Jul 29, 2016

Here's the FooBar edition...

Also from China, but no stinky

Why so much variation in beam torque wrench handles?

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