Today I am reviewing a Warren and Brown 1/4" (or 3/8") drive deflecting or split beam torque wrench, used for low torque fasteners. It’s model number 320510 or 320500.
If you’re looking for a torque wrench for small torque values a 1/4" or 3/8" drive model is often what you’re looking for. If you’re only needing to measure the torque on tightening bolts then a deflecting beam torque wrench is well worth considering as compared to the micrometer type, and it’s the deflecting beam sort I’m looking at today. This Warren and Brown split beam torque wrench comes in either a 1/4″ drive or 3/8″ drive model – model 320500 (eBay US, eBay AU, ) or 310510. The product page is here. The wrench comes in a plastic case:
The model number of the 1/4" drive wrench is 320510 – the 3/8" drive torque wrench with the same range is model number 320500. The model number of the wrench can be found on a sticker on the end of the plastic case:
The only other thing of note on the case is this number on the underside – presumably the model number of the case itself:
Open the case and we find:
Firstly, the little bar that clips into the end of the wrench to hold the sockets – this is the 1/4" drive variant, model 390090:
…and the torque wrench in question:
The little bar sits in this hole in the end:
The deflecting beam itself – with a sticker clearly showing which direction it measures torque in:
The trigger mechanism can be found on the end of the bar; you push in the black pin to prime it, and once the round trigger contacts the body of the torque wrench it clicks back out to let you know that the desired torque value has been reached.
The model number of the torque wrench can be found under the sliding scale where you set the torque value:
…the sliding scale itself. Measurements are available in inch pounds, kg cm and Newtonmeters. The wrench measures from 1 to 25 Nm, or 10 to 220 inch pounds. If you’re comparing it with a bigger wrench and are more used to foot pounds, that’s just under 1 foot pound to just under 20 (12 inches to a foot…).
You adjust the position of the sliding scale with this little thumb screw:
The handle is round:
The paperwork which comes with the wrench shows that it was inspected by "927":
The only other paperwork showcases Warren and Brown’s ranges along with providing a little bit of advice on how to use your torque wrench:
"927" is stamped under the head:
There are four little detents for holding the bar in – here’s a view of one:
Bar inserted:
Conveniently, the wrench has no trouble fitting back into the case with the bar inserted. Probably won’t fit with a socket attached, though.
In use the trigger mechanism is smooth and the click is easily audible above ambient room noise – depending on how noisy your workshop is, though, you may have to rely on the visual indication of it popping back out! The torque wrench is advertised as having all-steel construction and as “exceeding Australian standards”.
In terms of accuracy, this torque wrench is specified well above many of the other deflecting beam types available – it claims 2% accuracy over the entire range of the torque wrench, where others state 4%.
For some more details on why you might be considering the deflecting beam type over the micrometer type, read up on the differences here.
In terms of price, the Warren and Brown is more expensive than other brands at around $250 delivered on eBay – but the cheaper brands don’t offer 2% tolerance, more often 4%. One such example is the Kincrome K8032 at around $150 delivered. One thing of note, however, is that the Kincrome is not made in Australia.
If you’re looking for a torque wrench to deal with figures in the range of 1-25Nm this one is well worth a look.
Click here to find the cheapest prices for the 3/8" drive torque wrench or here for the 1/4" drive torque wrench!
For those interested in longevity in their tools, Warren and Brown have repair kits for the signal (part number 320398) and the wedge (part number 320595).
Warren and Brown’s available deflecting beam torque wrenches are as follows:
| Model | Range | Drive Size |
| 320500 | 10-220 in.lbs / 1-25Nm | 3/8-inch |
| 320510 | 10-220 in.lbs / 1-25Nm | 1/4" |
| 321500 | 4-90ft.lbs. / 5-120Nm | 3/8" |
| 322500 | 10-140ft.lbs / 10-185Nm | 1/2″ |
| 323500 | 20-220ft.lbs / 30-300Nm | 1/2″ |
| 324150 | 80-400ft.lbs / 100-540Nm | 3/4″ |
| 324500 | 50-300ft.lbs / 60-400Nm | 3/4″ |
| 325500 | 100-500ft.lbs / 140-680Nm | 1″ |
| 325510 | 100-500ft.lbs / 140-680Nm | 3/4″ |
| 325750 | 150-750ft.lbs. / 205-1020Nm | 3/4″ |
| 326500 | 200-1000ft.lbs / 260-1340Nm | 1″ |