Aldi Calipers...

A few years ago, I noticed a discrepancy between my metric micrometer and the "slipstick" gauge I was using at the time. As a result I started comparing all my measuring things both amongst themselves and eventually against a 25mm, 50mm and 75mm Mitutoyo calibration thingy. (Sorry about the poor language - it's because I can't at the moment remember the corect terms and am too lazy to look them up!)

What I found was that of the 6"/150mm rulers I had, one by Rabone Chesterman was wildly out on it's metric range. "Wildly" is just a description to denote lack of precision in our terms. Unless, of course, the Rabone Chesterman was spot on, and all the others incorrect.

I had a metric and an imperial micrometer (25mm,& 1inch ) a 150mm slide vernier with a 0.05mm resolution, a 150mm dial caliper with a 0.02 resolution, a Ronson (??) 150mm digital caliper and an Aldi 150mm digital caliper. Both of the digital calipers measure to 150mm with a resolution of 0.01mm. The metric micrometer read slightly high, the slide vernier appears spot on, the dial caliper and the Ronson (??) digital caliper were both reasonably consistently low whilst the Aldi was all over the place, both high, low and inaccurate. So much for Aldi!

Regarding cells. Again I have suffered poor cell life, however I did make two discoveries. One was to use the correct cell. There two types of button cell which appear satisfactory being the same size and having similar voltages. They are often sold as being equivalent. They are not - the correct one being the one with the slightly higher voltage. The second point I discovered (from someone else actually) was that the "Off" button does nothing of the sort - it merely switches off the display and leaves the rest of the circuitry still active and draining the cell. The same article also did some tests and discovered that Mitutoyo digital calipers had the lowest drain of all when supposedly switched off. This was by a factor of 10 I think.

As a result, I have bought a Starrett 150mm dial caliper with a resolution of 0.01mm and only use the digital calipers if desperate. Furthermore, I never leave cells in them - this also applies to the Wixey digital angle measuring device I have.

I should point out that I am not an expert in any of this, merely someone who has discovered these problems, in effect by accident.

Furthermore, I have reported on this elsewhere on this forum.

Regards,

Peter G. Shaw

All edit to correct the text.

Edited By Peter G. Shaw on 13/02/2013 13:14:21

Edited By Peter G. Shaw on 13/02/2013 13:15:03

Edited By Peter G. Shaw on 13/02/2013 13:16:52

Dont realy know about the Aldi calapers, but have a couple of the ones from Lidl which have srrmed to be fairly accurat - but they are only used for the initial sizing - the final sizing being done the oldfashion way with a micrometer (both inperial & metric) Is it that the modern "swarf" makers dont know how to use a mic. and must rely on visual electronic displays

I know you are going to say that I'm old-fashon, but some of the old ways take a lot of beating.

I think the problem is that the newer ones are made with 50% horse meat

Regards,

Tony

Hi Tony, perhaps they have found that they could actually recycle all the redundant horse shoes.

Peter, your calibration thingy is called a standard, but you should avoid direct contact with them, because the heat from your figures can expand them. I found that out with my Strarrett ones when I was checking my Starrett No.224 0-4" mic.

Regards Nick.

My imported calibration standard has a thick plastic sleeve fited to it. I thought it was to stop me losing it thinking it was an offcut! Now I realsie its for insulation. Came with a 1-2"/25-50mm mike.

Neil

Nick,

Thanks for reminding me of the correct name for the standards. You see, it's been too darned cold & damp to do anything other than skulk in the house!!!

Anyway, what I actually did was to bring everything into the house and leave overnight so that they were all at the same temperature. Since we have storage heaters, the temperature is reasonably constant around 60 or so degrees F which is what the standards were marked as being correct at. As was the Rabone Chesterman rule. Everything was then checked as quickly as possible and the results recorded. Now ok it won't be up to laboratory standard, but at least it won't be at one or other unacceptable end of the temperature range.

I think I either placed then on something and relied on the jaw pressure to hold them or held them by the plastic bits in the nylon jaws of a small portable vice. Probably both as to measure 100, 125 & 150mm I used them in series. I also carefully wiped each measuring face before using them.

I've got to say that this experiment, as much as anything brought home to me the inherent inaccuracies of our measuring gear.

Regards,

Peter G. Shaw

This document has some interesting specifications and comments on calipers: **LINK**

Six inch calipers should have a maximum error of 30 micron ( just over 1 thou) for outside measurement and 50 micron ( 2 thou) for inside or depth measurement.

As they say, don't trust calipers with no maker's name on them.

Having said that I use Lidl ones for quick and dirty measurements.

Russell.

Cheap calipers make excellent back scratchers...

Regards,

Tony

sod's law!! dropped a good caliper at work last night. Lucky for me Mitutoyo coolant proof ones are on offer, still £100 i could have done without spending.......................

sod's alive and well, just bust the £100 caliper by dropping a gauge on the scale.

Back to cheapo ones for me!

Broke the scale on my first calipers, was using them on the lathe, and bumped them on the tail stock, cracking the glass cover, glued a bit of plastic over it and they carried on for quite a while till I bought a new set. Ian S C

the caliper loses/gains up to 8mm over the damaged part. Mituyoyo say it can't be fixed..........

Hi Jim,

I suspect most faile because of damage to the head not the scale. You might be able to get a scrapper with an OK scale of fleabay or thorugh a wanted ad?

Neil

I have used some black calipers from Aldi 'on-machine' for a few years, they've been dropped hundreds of times, been covered in oil, had smashed screen and they are only 0.02mm out.

The blue ones I've seen in Aldi recently were terrible though.

One morning last week it was a bit chilly in the shop, this makes my nose run, I was using my aldi caliper when said dew drop dropped on to caliper and it started to go hay wire, I was snot amuzed, I put them to one side and used my spare set, a couple of days later I tried the snotted up set and they were working fine.

So having tested them I can say they are snot proof.

Stew

I think they all work on a capacitive principle, so conductive fluid like snot would upset any make, until it dried up.

Neil

I have a few Aldi digital calipers, as they are cheap they can be left in various locations, and used for rough checking, eg odd bits of precious metal (otherwise known as scrap), preliminary measurements etc.

When it comes to the final measuring, it has to be the mike and the dials. Calipers, having a knife-edge on their legs, are prone to inaccuracy as they have to be held perpendicular to the workpiece. Mikes having a flat anvil naturally find the right-angle.

HomeUse....... there are old swarf makers who use digital devices, because they can no longer see the tiny engravings on the old-fashioned kind, without the use of a magnifier - which is where a 3rd hand would be useful.

Phil

I bought a relatively inexpensive 8" calliper recently which suffered an unfortunate accident, I smashed the screen! I had not even realised it was glass and a minor impact - the sort that can be expected in a workshop, broke it. It should not have been made of glass, and to make matters worse the screen is somewhat convex thus standing proud and the first thing that will make contact. A poor buy then...

A better purchase to help a pair of aging eyes was a new Mitutoyo mic to replace my 45-year old Moore&Wright imperial mic (which I bought new ) Not only does the Mitutoyo have a large, clear display, it converts between mm/inches, has 30mm capacity, and is very quick to operate - taking just 10 turns to cover the entire 30mm range.

I use a cheap plastic/nylon dial caliper for all "rough "jobs. These are very easy to read, don't have batteries and are accurate enough for stock measuring etc.. Resolution 0.1mm. and accurate.

The Mitutoyo will also have a glass display, although it may well have a plastic sheild in front of it.

Neil