Model Boat Mayhem
Technical, Techniques, Hints, and Tips => Other Technical Questions... => Topic started by: OMK on August 26, 2009, 12:43:58 am
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Same as that.
I bought me an el cheapo digital caliper, if only to keep abreast of things. Nine times out of ten I find myself invariably reaching for my old analogue/imperial one.
Incidentally, re: digi caliper -- I would gladly buy anyone a pint or three if you could tell me how to replace the battery in the damn thing.
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There appears to be a slidey cover thing with an arrow on it to the right of the screen, is the battery under it?
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Nah, the slidey thing only serves as a thumb grip. There are no visible screws or cover plates - not even on the underside. Since it cost just a measly eight quid I'm starting to wonder if it's meant to be binned once the battery is depleted. The measly price also reflects the build quality. Accuracy is fair to middling, but feels more like a toy rather than one of quality.
Although, I'd still like to find out if the battery is replacable before it gets relegated to the bin.
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The panel that he is referring to is the rectangular panel to the right of the digital display. Slide that panel to the right to access the battery. I have the same set of calipers,usually left on Imperial I have to say.
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Yep - I'm hearing you, but the panel you mentioned just won't budge. It seems to be devoid of any tell-tale seams. Further inspection reveals no indication of any panel/plate/cover allowing access to a battery compartment. It's totally hidden.
I'm brassed off with the thing. Watch this..... I'm gonna attack it with a pocket knife/screwdriver/hammer...............
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You were both right all along.
The cover needed a real hefty amount of persuasion with the blade. Talk about tight. A guilty-looking blob of snotty stuff held the thing fast.
Take a look. It even broke the tip off my favourite blade.
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They are fitted with a tiny Watch battery. Usually accessible from a sliding cover. Try sliding at the edge somewhere.
Hope this helps
Ken
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Handy tip - if you want to scale the measurement up connect it to a 6v gel cell........ %% %%
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<*< ...PMK.......these little L1154 disc batteries are only 1.5 Vdc
A digital caliper battery in good charge will display 0.00 mm when closed
A digital caliper battery in low charge will display 0.00 mm when closed
A digital caliper if connected to 6Vdc will display ........... mm when closed {-) O0 >>:-
Tis not worth the scaling concept...... as this :embarrassed: will only convert your caliper into an adjustable spanner with ZERO display in the TV screen..........
Tis also amazing how many degree engineers cannot read an older vernier calliper without that same electronic TV set in the corner
Tis also amazing how many young trades persons can read a conventional vernier calliper in mm & 1/1000 of a mm & nominate the correct dimension, however cannot understand & read the same dimension in the imperial [inches "] dimension at the same time
Bogstandard & I have discussed this on a number of occasions....... O0,
Naturally in OZ, current engineerings Drawings are ISO Metric, but many still current older Drawings are in their imperial dimensions
The simple example is a 1" shaft on the imperial Drawing is listed as 1" -.001/+.000 ... so the young trades person could report this as 25.40 to 25.3746 & both are correct...........
Talk about how thick........how thick is a sheet of paper?..........in my day [bond paper] was approx 0.0035" .....so 25.4 x 0.0035" = 0.0889 mm but that is a number I cannot visualize .........%% Derek
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You will find that even the most expensive digital calipers are not classed as a precision instrument. They should only be used for a guesstimation.
The reason for that is in the way it actually takes a measurement, plus the length of the measuring area. They are really only classed as being accurate to 0.002" (0.05mm). The internal nibs should really be ground off as they are no use to man nor beast, especially in the way they measure internal curves, like a tube or cylinder bore.
So really they are just an almost accurate form of adjustable spanner.
I have many sets knocking about the shop, just used for quickie rough measurements, and when the battery gives up after about a year, they are discarded and replaced with a new cheapie one from somewhere like Aldi. I always have a couple of spare new ones in stock.
There are very accurate digital scaled instruments, like depth gauges. But that is because they work on a different principle for measuring than the digivern.
Bogs
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I love mine. I use it every day. Not for the accuracy in readouts, but for comparisons between items. ie; noting the difference between drill diameters. It's also useful for marking out cutting lines on the old plasticard. ( much better than a ruler, at my age!!) When the display began to fade, I removed the battery and cleaned the terminals and replaced it and it came back to life. I would really miss this tool.
Anyone notice the timing of my last post with regard to the flow of the letters? Seems mine got lost in the 'ether' for a while. %)
ken
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No sweat regarding the timing, Ken. His Martinness had the good sense to shuffle this thread from an earlier one, hence the timing hiccup. My fault because I originally posted on the Springer pages and ended up veering slightly off topic.
You made a good point about the varying drill sizes. I bought me a set of Erbauer titaniums. Each one checks out perfectly on both the analogue and digi calipers. In comparison, a set of cheapo bits from the pound store all measure slightly larger than specified -- each and every one. Hardly surprising though.
Just for a giggle I might just well stuff six volts up the digital.... if only to satisfy Mr Bishop's sadistic humour! ;)
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I just had to be different. I bought a pair of M&W digital calipers (£Don't ask...........it wasn't cheap) and I use cheapo drills! It is useful for checking the thickness of styrene sheet, hole spacings for drilling heat-sinks and motor mounts, diameter of machine screws etc. An improvement on squinting at a metal rule with my slowly degenerating eyes.
For proper engineering then there's no substitue for the real Vernier stuff unless you're prepared to sacrifice limbs to buy lab-quality instruments and calibration. The measurement room at Loughborough University had a set of slips in it that were so accurate that the little cubicle was kept warm with a set of 60W bulbs to simulate the heat output of a human body when no-one was in there. That was nearly 40 years ago - I wonder what they have now?
BTW if you need new button cells then check out Component Shop's prices. You can buy a card of five for less than Craplins charge you for one cell. They're also good for those 12v batteries in door alarm/car remote zappers. "Just a satisfied customer", as they say.
FLJ
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You're right about the button cells from Component Shop Dave. I bought some for my remotes, Staples price £2 each, Component shop 10 for £2.50 + £1 p&p.
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FLJ.......here is a current "ish" nomination re standards for calibration.......but I am sure there are thousands of later documents {:-{
http://www.hn-metrology.com/isogum.htm
However it must be remembered to always nominate realistic tolerancing to suit the application... O0 ....Derek
Oh BTW...I am the owner of a number of Action Electronics bits & pieces which have never been commissioned due my conversion to steam.........but I may come back & advice some in the future...... :D
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Serves yer all right, yer should have gone to LIDL, their version has the CR2032 cell (Same as the memory battery in compewkters AND the ones I got as freebies from Messrs Morrisons two Chrissies ago) and LIDL's were only £7.99 as opposed to ALDI's £8.99 for the same thing a week later. O0
Regards Ian.
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I bought one from Aldi over 3 years ago, and it's still working fine. It cost me $20 Australian.....and it's easy to change the battery O0
Peter.
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hi mine is also from aldi and works as good as any other on the market :-))
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I recently purchased 10 of these batteries on ebay 10 X AG13 LR44 SR44 L1154 357 A76 LR1154 Button BATTERY for the princely sum of $2.99AU just over a quid for anyone interested the sellers ebay name is eshop724
Damien
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Hi all
I for one Loved my digital calipers. But, mine were the exspecive ones from Mitutoyo and I used them every day in the quality control deptment where i use to work. But alast I had to sell all my machining tools this last year for the money, I am one of the many ppl that lost their jobs when the big three US auto Manufactures lost there a ;Des.
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Sorry.....but one of the fundimental flaws in life >>:-( is when the battery in the vernier caliplier is dead
In OZ......young trades technicians are taught to read a vernier caliper [without the TV screen] in the corner....but only in metric units = OK
Ask the same young trades technician to measure ......determine then confirm the corresponding imperial dimension & they are lost <*<
Thankfully....calibtated micrometers are used for the final product.......
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I agree with you I learned how to read vernier calipers and mircometers before i ever bought my digital ones. but with the digital ones you can set them so you can read the tolerances insted of the actual size. I use to inspect large batches of parts and would set my mic or calipers with gage blocks and then read to the diff. +/- tol. O0
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In a nutshell it doesn't matter how accurate it (the measuring instrument) is so long as you use the same one for all your measuring. %) %)
For example let us say you have a measuring rule, steel, timber, tape, or whatever and it is inaccurate by 10%.
So long as you use that same rule, all your dimensions will be correct. For instance if you measure the length of the hull from a plan at 13 whatever and transfer the measurement to your material it will be 13 whatever and will accurately be the length of the hull as shown on the plan.
However if you want to give dimesions to a third party to make something to fit the hull or even make the hull, well then that's when there is a problem and standard accuracy is essential.
So for personal use keep using the cheapies they work. :-)) :-))
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An old topic but worth reviving.
I have an expensive digital calliper, which for some reason eats batteries, i turn it off and the display goes off but it seems to be still running! This means that a battery goes flat every few days, i have no idea why. The only recourse was to remove the battery after every use, because the batteries for it are expensive. The upshot was i bought a cheapo calliper from ebay for everyday use, the drawback being it only reads to 1 decimal place.
Anyway getting back to the expensive calliper i found that leaving off the battery cover i could in fact use any round battery of the correct diameter and voltage, ie 1.5volts. I can source these 10 at a time on a backing card for 1 euro :)
So the point I’m making is that any round battery will fit a calliper if you are stuck for the correct one.
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Try letting it turn off automatically , most do , the correct battery is an LR44 or whatever equivalent No. appears next to it on the cheapo battery pack cards ,AG13 / SR44 / A76 etc, other button cells are either too thick or to small in diameter . . .
For newbies . . . .
If you're new to digi's getting water inside the reading head causes all sorts of malfunctions , just leave it somewhere to dry out & the problems disappear . . .
As the caliper gets older the slide track starts to wear , giving different readings at the tip of the jaws from the ones close to the main frame , just reset the slide screws until you get the same readings at both ends of the jaws .
Bill
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I had a similar problem with mine. The problem was caused by the foam box lining pressing the 'On' button when I closed the case, or stored the case on its edge (caliper leaning on its side against the foam). Now the foam has flattened a little (I could have helped this with a knife) and I store the case flat on the shelf, the problem has gone.
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No that doesn't work Bill, even though the auto shut off works, the battery is still flat after 3/4 days, so it may be a short someplace?
But what I didn't make clear is that you can use any thickness battery as long as diameter is correct - just leave off the battery cover, which I had been doing because of the constant need to remove the battery.
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Same problem good point on the foam pressing the button. Will leave battery out from now on. Thanks
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I have a digital G Clamp.....alas a hunk of iron fell on the face & smashed the display <*<
On further inspection it was not the display as such but a piece of glass covering the actual electronic pad
The on/off button does not work >>:-(......but the display just blinks......2 seconds with mm......2 seconds with the dimension
The UOM [units of measurement] button between " & mm also works
That was about 2 years ago.......battery is still powering up the device......day in ...day out
Seems such a waste to condemn it to the bin :P
The image captured confirms the mm displayed but no digits...bit it's OK..... I know they will show up in a sec
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I just saved a lady of my acquaintance £480 pounds by being able to change batteries in her Honda car keys. Honda couldn't open them 'cause one had a rusty screw and one a damaged head. They wanted to charge her £240 each for new ones.Robbing swine.I drilled the head off one and will drill it out later The other one I got the screw out and drilled it out for a 7BA nut and bolt. Made the nut captive with Gorilla glue. Used plastic magic as a primer as it is an odd plastic but Plastic Magic seems to stick anything plastic except polythene types. The batteries? Well one was £2 but 5 for £3:66 Panasonic CR1616 should last a bit if she keeps them in the fridge. Slightly off topic but I thought it worth a mention
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The foam could have been shrunk with a quick flash of a lighter flame. Magic
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Use mine to measure thickness of mdf etc - ( produce laser cut kits etc so thickness is critical for joints). Bought from Maplins on special for 10 quid . batteries go flat in about 3 months so always buy packs of six - unused they store for up to two years and are the cheapest type of button batteries here. Unusual in that its a 4" model not the usual 6" . Better half is always trying to swop her standard type for mine. Would never part with it , most useful tool especially as one gets older and ordinary caliper markings become too small to read............
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Also, try buy better batteries, Duracell, Energizer etc, mine works MUCH better with good batteries! :-)
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I like the digital calipers due to the amount of stuff i have that the aliens came down and played with.
they miniaturised all the markings and lettering on every thing i own.
i am now wearing reading glasses and using a magnifying lens to stand half a chance of reading the digits.
now what i have found is that the wife bought me the cheapest digital caliper on the net, it was about £1.99 free post.
she got this purely as a joke. But i compare this to my Moore and wright micrometer and the cheapo is extremely accurate !!
i have also had it compared to a very expensive mitutoyo and was accurate until it got past 5 inches then lost 0.001".
The good thing is. i can actually see the digits. its a cheapo plastic carbon fibre lookey likey if you're about 10 yards from it.
But the digital readout being big just makes life so much better.
Now i am looking at getting an upgrade to the all stainless steel ones with fractions on them too.....
i am almost down with the kids ha ha
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I think the aliens came to me first.... I did as an experiment buy a set of digital callipers from a well know inter web site, £4-99 delivered...and wow, checked the accuracy and just about spot on, it reads in decimal and something called millimetres, not sure what they are and I don't suppose they will catch on {-) {-) {-) {-)
Much lees eye strain these days
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I find them millimetres are brilliant. the other day I measured something and it was 14 inches and 7mm.. so they are handy.
for the sum of £4.99 they should be spot on too.. that is a lot of wonger in proper English money £4,19.11 d :police: