Mitutoyo'ising' cheap Aldi Calipers

I bought one of Aldi's current offers for £9.99 unseen. Frequently in Aldi someone has already unsealed the packaging which is handy as its lets you the item in advance. This time I waited until I got home.

As with many products these days the manufacturers are constantly finding ways to cut the cost of making the articles and whilst these calipers look very similar to the last ones I bought the 'fit and finish' have suffered. One big improvement though is the Lithium coin cell.

The feel and action of these calipers is a long way behind Mitutoyo and other quality calipers but a few minutes work transformed my purchase to a really usable tool. I prefer their easy zero facility to the default 'absolute' of the Mitotoyo ones. Power off seems to work (no idea if it actually extends battery life) but for me the main thing is that it remembers the value when its switched on again.

The actual sliding action was horrible! it felt rough and jerky and even with the thumbwheel it was hard to creep up to a set value. The surfaces of the beam were really very roughly ground, it looks more like a 'brushed' decorative finish that is put on kitchen equipment rather than a surface ground machine surface.

I used a diamond hone, hand held to carefully remove the crests of the rough grinding. Once the very tops are removed the grinding marks are a very good guide to where the highs and lows are and by holding the diamond file flat to the surface its possible to smooth the surface without destroying its basic 'accuracy'. I dont know the grade of grit I used but its Arc's yellow coloured diamond file (the finest of the set of four).

Of course dismantling and fettling the calipers will negate the guarantee but from my point of view they would probably have lain unused because of the rough feel (and sharp edges).

Ian P

+1 for using a diamond hone to improve the feel of a cheap digital calliper. Mine is now silky smooth and I doubt there is any significant dimensional change.

Mike

Cheap modern tools can often be as accurate as more traditional ones but the finish!!!

A real life example:

Lost 1960s Moore and Wright 1-2" micrometer.

Bought replacement Moore and wright 1-2" micrometer. Pleased with purchase.

Moved workbench and found original micrometer. Difference in feel is bigger than the whole world!!!

The feel of the old one is so much nicer. But then, out of curiousity, I tried them both on a some of slip gauges and the new, rougher feeling ones seem to be more accurate, not an error that can be adjusted out either, but different across the range.

If this was an exam question it would be followed by - Discuss!!

Discuss:- The rubbing surfaces will bed in over the first fifty years or so, so they feel smoother, but get less accurate. See if it's changed much in another fifty years...

Shouldn't laugh. My favourite micrometer is the 0-1" M&W (965b) that dad bought in the '50s. it still lives in its original wooden box when it isn't in use.

Edited By Mark Rand on 23/08/2018 22:15:24

I agree with Mark.

Neil