Just a quick review of some cheap calipers I got from ebay recently. I hope this review is of use for other like-minded cheap-skates out there
The link is https://www.ebay.co.uk/itm/New-6-15...tainless-Steel-Measuring-Tool-UK/333273675716
Now, first of all, obviously I understand that for 4.99, including delivery, they are not going to be nice, but I wanted a set of cheapo calipers that I could throw about in the garage/shed. I also did not want digital calipers, as they seem to always be out of batteries when I want to use them (I have two pairs already).
Anyway, as expected,they are a bit rough and ready.
As they came:
Wiping the calipers with paper, there was black residue from the machining, and also the machined edges were all sharp and quite horrible. The sliding action was horrible, as it felt really "gritty".
I decided that they were simply too horrible, so set about trying to fix the issues.
Disassembly was very simple. Only the two screws on the right hand side needed to be taken out, which allowed me to clean the whole caliper with some soapy water, after which the parts felt clean.
The groove at the back was/is really horrible looking, although I don't think this is what causes the grittyness:
I used a bit of sand paper to dress all the machined sharp edges, which made the calipers slide nicely, and the gritty feeling was hugely reduced.
Next up, checking the accuracy of the jaws. No photo, but there is only the tinyest sliver of light coming through between the big jaws, which is probably down to the jaws not being lapped / ground, but rather machined "flat".
The smaller jaws, for measuring internal diameters is a different story. The overlap is about 0.5mm when the main jaws are fully closed:
Another thing that needed to be adjusted was the vernier scale itself. Out of the box, with the jaws fully closed, it read 0.20mm. Luckily the scale can be adjusted by loosening the three scews that hold the scale on, and re-positioning it before doing the screws up again.
All zeroed in:
Moving on to accuracy, which I checked with my slip-gauge-set. The columns below are: Actual (as per slip gauge), measured, error (up to the 0.02mm accuracy):
0.020", 0.510mm, measured 0.02mm too large
0.500", 12.68mm, measured 0.02mm too small
1.000", 25.40mm, no error
2.000", 50.80mm, no error
4.000", 101.60mm, no error
Not sure what I'll do about the internal jaws yet - maybe I'll just figure out how much I need to adjust the measurements by to get accurate measurements, but at the moment they're useless, at least if the measured value has to be used elsewhere with other measuring devices.
All in all, I am surprised by the accuracy. The calipers were quite horrible indeed when I first received them, but cleaning them and dressing the sharp edges have made them tolerable. They're never going to be as nice to use as my proper old ones, but on the other hand I don't have to worry about them in the same way either.
If I lost these, I'd probably buy another set the same.
The link is https://www.ebay.co.uk/itm/New-6-15...tainless-Steel-Measuring-Tool-UK/333273675716
Now, first of all, obviously I understand that for 4.99, including delivery, they are not going to be nice, but I wanted a set of cheapo calipers that I could throw about in the garage/shed. I also did not want digital calipers, as they seem to always be out of batteries when I want to use them (I have two pairs already).
Anyway, as expected,they are a bit rough and ready.
As they came:
Wiping the calipers with paper, there was black residue from the machining, and also the machined edges were all sharp and quite horrible. The sliding action was horrible, as it felt really "gritty".
I decided that they were simply too horrible, so set about trying to fix the issues.
Disassembly was very simple. Only the two screws on the right hand side needed to be taken out, which allowed me to clean the whole caliper with some soapy water, after which the parts felt clean.
The groove at the back was/is really horrible looking, although I don't think this is what causes the grittyness:
I used a bit of sand paper to dress all the machined sharp edges, which made the calipers slide nicely, and the gritty feeling was hugely reduced.
Next up, checking the accuracy of the jaws. No photo, but there is only the tinyest sliver of light coming through between the big jaws, which is probably down to the jaws not being lapped / ground, but rather machined "flat".
The smaller jaws, for measuring internal diameters is a different story. The overlap is about 0.5mm when the main jaws are fully closed:
Another thing that needed to be adjusted was the vernier scale itself. Out of the box, with the jaws fully closed, it read 0.20mm. Luckily the scale can be adjusted by loosening the three scews that hold the scale on, and re-positioning it before doing the screws up again.
All zeroed in:
Moving on to accuracy, which I checked with my slip-gauge-set. The columns below are: Actual (as per slip gauge), measured, error (up to the 0.02mm accuracy):
0.020", 0.510mm, measured 0.02mm too large
0.500", 12.68mm, measured 0.02mm too small
1.000", 25.40mm, no error
2.000", 50.80mm, no error
4.000", 101.60mm, no error
Not sure what I'll do about the internal jaws yet - maybe I'll just figure out how much I need to adjust the measurements by to get accurate measurements, but at the moment they're useless, at least if the measured value has to be used elsewhere with other measuring devices.
All in all, I am surprised by the accuracy. The calipers were quite horrible indeed when I first received them, but cleaning them and dressing the sharp edges have made them tolerable. They're never going to be as nice to use as my proper old ones, but on the other hand I don't have to worry about them in the same way either.
If I lost these, I'd probably buy another set the same.