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User avatar
By bugbear
#1194290
Bodgers wrote:
NickN wrote:I'm cursed to be old enough to have been influenced heavily by imperial but young enough to have been taught metric at school, and it does my head in, I end up using both most of the time as I cannot VISUALISE anything in metric, but I struggle to CALCULATE anything in imperial... Grrr.. (hammer) :oops:

I'm glad I've never had to deal with imperial measurements (with the exception of miles - which also needs to go so we can work out fuel consumption more easily). It's the fractional maths that's the killer.

I recently acquired a vernier gauge with both imperial and metric scales. A normal engineer's vernier reads in 1/1000 of an inch, and is fine.

But the one I just got read is coarser - reading to 1/128".

Which ought to be easier, right?

Try this, if you love imperial, and deem fractions convenient:
http://www.stefanelli.eng.br/en/use-ver ... onal-inch/

BugBear
User avatar
By NickN
#1194323
"In the topic vernier scale: simulator of reading and interpretation in fractional inch resolution 1/128″ we saw how each division of the main scale represents 1/16 (one sixteen avos) of inch. We saw also that this space is divided by the vernier by eight and that the value of the measure is obtained by the sum of the integer, the fraction of the main scale is the fraction of the nonius. However, the measurement value is obtained by adding the whole, the fraction of the main scale and the fraction of vernier."

:shock:

That noise you thought was a sonic boom was my head exploding...
User avatar
By NickN
#1194327
DBT85 wrote:You planning to do the same for the others now that you've got it down?

Have you decided how to do the tenons? Will you try splitting?


Yes, I think I will do the remaining six by hand too, it's good practice anyway and quite enjoyable.

The tendons, hmm, I think looking at the grain of the rails I could do, but will use a hand saw for the first one at least, as I don't have a bandsaw yet, and plus this is an ideal hand tools project anyway.
User avatar
By bugbear
#1194330
NickN wrote:"In the topic vernier scale: simulator of reading and interpretation in fractional inch resolution 1/128″ we saw how each division of the main scale represents 1/16 (one sixteen avos) of inch. We saw also that this space is divided by the vernier by eight and that the value of the measure is obtained by the sum of the integer, the fraction of the main scale is the fraction of the nonius. However, the measurement value is obtained by adding the whole, the fraction of the main scale and the fraction of vernier."

:shock:

That noise you thought was a sonic boom was my head exploding...

But imperial is so much more natural:

Add these values to the whole of the main scale, (7/16 = 14/32 = 28/64 = 56/128 + 5/128 + 1 = 1 61/128)

What could be easier than that? (*)

BugBear

* rhetorical AND sarcastic :D
User avatar
By Tasky
#1194392
DBT85 wrote:Great start there Nick. Nice and neat.

I agree... and am somewhat jealous!

DBT85 wrote:I'm one of the few in my age group (32) it seems that can deal with both.

I can, but it's a royal pain in the backside.

DBT85 wrote:I wonder what the govt will do when 100% of the people alive in the UK were only ever taught metric at school.

Stop selling things with the imperial measures in smaller text beneath the metric ones. Not much else.

NickN wrote:That noise you thought was a sonic boom was my head exploding...

This bit is the easy part - He's taking one 16th of an inch and further splitting it into 8 - which is where 128 comes from. In other words, a quarter of a 32nd, which is the smallest bit on a standard tape measure or ruler.
Younger folks should recognise these from using computers, with 4, 8, 16 and sometimes 32 gigabytes of RAM being quite common. 8, 16, 32, 64 and finally 128GB of data storage are common USB flash drive and SD card sizes, so even mobile phone users can probably cope up to this point.

bugbear wrote:* rhetorical AND sarcastic :D

Yeah, they said that about imperial money... I remember "quick ways with money" was anything but - All about adding pennies and calling them shillings, before subtracting another amount of pennies from those shillings, and then dropping the remaining shillings back down to pence for counting, before adding the remaining pennies back up to make shillings again... or something weird like that. Oh, and shillings often had a variety of sub-coins that represented sort-of fractions of a shilling, but ultimately were allowed to be considered as pennies because there are 12 pence to the shilling, but a penny is more than 1/12th of a shilling... or a farthing, or a thruppunce, or a happunce, or a Newpunce even...while a shilling was actually worth two shillings after 1967...

Yeah, sure, easy as pie.
I know what it means when someone is thrupenny-bitting round a corner on a motorcycle, but damned if I know what thruppence would've ever bought you. Ninepence would get you an intermission albatross, but you don't get wafers with it.
User avatar
By DBT85
#1194418
NickN wrote:
DBT85 wrote:You planning to do the same for the others now that you've got it down?

Have you decided how to do the tenons? Will you try splitting?


Yes, I think I will do the remaining six by hand too, it's good practice anyway and quite enjoyable.

The tendons, hmm, I think looking at the grain of the rails I could do, but will use a hand saw for the first one at least, as I don't have a bandsaw yet, and plus this is an ideal hand tools project anyway.


Sounds like the next project is building Mattias Wandel's bandsaw :P

Hoping to get cracking on mine in the new year as the last large obstacle has been removed from my would be workshop. Now I just need to have a tidy, a bit of paint and I can get going!
User avatar
By El Barto
#1194521
NickN wrote:So, amidst all the chatting about chisels and metric stuff, I actually spent some time in the workshop working on my first ever mortises today... and have to say I'm quite happy with the result. First one took about an hour, second one about half that, and I'm in no rush anyway, for me the hobby is as much about simply relaxing and doing something practical as it is about actually finishing anything.

Now the hardened old-timers may chuckle, but I was ridiculously happy when the reverse side 'tunnelling' of that first mortise actually met up dead straight with the face side excavations! Such simple pleasures but for me it's what it's all about, particularly having got to middle age and never having had the chance even while at school to try woodworking.


First ever mortise well underway:

Image


Breakthrough - it lines up!

Image


Second mortise - already looks much tidier than the first:

Image


And a finished first leg, with haunch housing also created:

Image


Bloody hell those mortises are brilliant. Mine were positively hideous by comparison. Good job.
User avatar
By NickN
#1194601
Haha, I must admit I did reflect to myself afterwards "that wasn't bad for a two quid chisel"!

Thanks for the encouraging comments though, all, nice to know that I don't seem to have made any major mess ups (yet). Second leg is in progress, hoping to get the four done before I am unable to move for over-eating on the 25th... :lol:
User avatar
By DBT85
#1195090
Bodgers wrote:
DBT85 wrote:Same difference!
The Lidl chisels have hornbeam handles ;)

Sent from my MI 3W using Tapatalk

Weird, the 5 sets I have here bought a few months ago are all European Beech! Guessing it's whatever is available at the time of the production run.
User avatar
By NickN
#1195123
Until this year the Lidl chisels did indeed have Hornbeam handles (Aldi use Ash I believe) - but they changed them this year to European Beech, and bumped the price up a 'lidl' too I think.

I've only got the one set, figure that should last me a good few years and by then wood will be a thing of the past in a Britain covered by shoebox houses...