"bare"

[bambuko]

What does "bare" mean when applied to dimension, please?
I guess it is peculiar model engineering lingo? (never recall seeing it on another drawing? but I could be wrong...)
I suppose it means +0

[Roger]

I guess it means +0 and -whatever you like! It's a term that belongs in the bin along with the other vague expressions used in the past before proper tolerancing became universal. I doubt if you'll find it anywhere else in use today, but it lingers on in Model Engineering, as do Imperial measurements, because almost all of the UK designs date back to the 1940's

[bambuko]

I know where it belongs...
I was hoping for "translation" (I am looking at some old ME drawings).

[ettingtonliam]

I recall it being used by LBSC, among others. He used 'bare' meaning slightly less than the nominal size (i.e 1/8" bare) together with'full' meaning slightly more than the nominal diameter (i.e 1/8" full). Don't forget that back then, many people at home probably didn't have access to precision measuring equipment, so no good saying 0.120" or 0.130", as we'd have no way of measuring that.
OK, so even then, Rolls Royce wouldn't have used that sort of measurement, but whether industry pre WW1 would use 'full' and 'bare', I don't know.
My favourite, for a small dimensional change remains that allegedly used at Inchicore Railway Works in Ireland 'The black of me nail'. I wonder how many microns that translates to?

[jma1009]

Inchicore - Maunsell and Joynt! wonderful stuff!!

i agree with richard 'bare' equals minimum fit ie push fit so perhaps 1/2 thou. others may have different views!

cheers,
julian

[ettingtonliam]

I translated bare as 'easy running fit' so maybe a couple of thou under, rather than a push fit, and 'full' as being a tight fit, not quite a press fit.
It obviously varied depending on the nominal diameter, the amount under or over for full or bare being much more for a 1" component than for a '1/8" component.

[Jim Woods]

My father was a carpenter and used "Bare" and "Full" measurements. as those above have said, Bare is an Infinitely varible amount short or under the given size and Full being the same amount over the given size. As a toolmaker I used them to confuse the drawing office lot when updating the drawings they did after the tool or machine was finished. Graduate "engineers" are easily confused with old fashioned terms and bad spelling like I use :-)

Jim

[Roger]

Feb 3, 2016 2:13:10 GMT Jim Woods said:

My father was a carpenter and used "Bare" and "Full" measurements. as those above have said, Bare is an Infinitely varible amount short or under the given size and Full being the same amount over the given size. As a toolmaker I used them to confuse the drawing office lot when updating the drawings they did after the tool or machine was finished. Graduate "engineers" are easily confused with old fashioned terms and bad spelling like I use :-)

Jim

Ah yes, Graduate 'engineers', that old side swipe at those who study Engineering to a level that the old hands haven't. Some of us have done both apprenticeships and a Degree, so can appreciate both the practical and theoretical aspects of Engineering. Don't assume that having a Degree means that you can't wield tools just as well as anyone else.

[Tony K]

Feb 3, 2016 8:05:23 GMT Roger said:

.....Ah yes, Graduate 'engineers', that old side swipe at those who study Engineering to a level the old hands haven't. Some of us have done both apprenticeships and a Degree, so can appreciate both the practical and theoretical aspects of Engineering. Don't assume having a Degree means you can't wield tools just as well as anyone else.

Mmm! sensitive subject then - nerves being touched here.

[Midland]

That is the trouble with graduate engineers, they cannot think of beautiful 'full' things when they are 'bare'! My mind just wanders, ah Sofia Loren!!!
D

[Roger]

Feb 3, 2016 9:36:53 GMT Tony K said:

Feb 3, 2016 8:05:23 GMT Roger said:

.....Ah yes, Graduate 'engineers', that old side swipe at those who study Engineering to a level the old hands haven't. Some of us have done both apprenticeships and a Degree, so can appreciate both the practical and theoretical aspects of Engineering. Don't assume having a Degree means you can't wield tools just as well as anyone else.

Mmm! sensitive subject then - nerves being touched here.

Not particularly, but a lot of 'Old hands' have a chip on their shoulder about these things, and make assumptions that aren't justified. There are many Graduate Engineers, young Adam for example, who are skilled in the workshop. I think there's an inverted snobbery from the 'craft' side of the fence for some reason, where respect for Academic knowledge would be more appropriate. Much of the knowledge of the craftsman can be picked up by the Graduate Engineer even if he doesn't have those from his education. The reverse is not the case, and I suspect that ignorance of what goes into an Engineering Degree makes them feel inferior. It's an attitude I've come across a lot in my career and it doesn't hurt to face it down when it emerges. Pretty much all the advances in modern Engineering have come from Graduate Engineers, not from craftsmen.

[bambuko]

Look guys, you want to discuss your chips on your shoulders ... go somewhere else :-)
Rest of you - thank you for constructive and interesting replies. I even enjoyed small detour to Ireland :-)

[Rob]

Feb 3, 2016 10:21:18 GMT Roger said:

Feb 3, 2016 9:36:53 GMT Tony K said:

Mmm! sensitive subject then - nerves being touched here.

Not particularly, but a lot of 'Old hands' have a chip on their shoulder about these things, and make assumptions that aren't justified. There are many Graduate Engineers, young Adam for example, who are skilled in the workshop. I think there's an inverted snobbery from the 'craft' side of the fence for some reason, where respect for Academic knowledge would be more appropriate. Much of the knowledge of the craftsman can be picked up by the Graduate Engineer even if he doesn't have those from his education. The reverse is not the case, and I suspect that ignorance of what goes into an Engineering Degree makes them feel inferior. It's an attitude I've come across a lot in my career and it doesn't hurt to face it down when it emerges. Pretty much all the advances in modern Engineering have come from Graduate Engineers, not from craftsmen.

To add some balance to this discussion; it's often the experience of being 'on the job' that counts rather than theory learned from a degree. For example, production is down costing a million an hour. The graduate uses their education to study the problem, work through the options and come up with a solution using all the techniques they have been taught, and quite rightly so. The guy without the degree that's been doing the job for the past 30 years has seen it all before and knows what to do immediately in a way that would never have been considered by the graduate because it wasn't part of what they were taught, saving vast sums of money.

There's often a good reason why 'old hands' don't view fresh faced graduates in a wonderful light, and it's not just jealousy or a feeling of inferiority. I also think it's a little unfair to suggest that a craftsman couldn't learn the theory.

I say this as a holder of a degree who has learnt far more 'on the job' than I did at university. So much so that I could happily have gotten by without the degree at all if it was possible to get the job without the piece of paper.

As always, two sides to the argument

[jackrae]

Definition is quite simple - it's exact dimension minus a midge's dick

[steam4ian]

Feb 4, 2016 8:45:03 GMT jackrae said:

Definition is quite simple - it's exact dimension minus a midge's dick

Or a condom.

[ilvaporista]

As they used to say where I worked. The only thing smaller than a midge's wotsit is the hole in the end.. And that is your 'bare' measurement

[pault]

But is a gnats dick bigger or smaller than a midge's

[ilvaporista]

Feb 4, 2016 14:46:17 GMT pault said:

But is a gnats dick bigger or smaller than a midge's

Now we are getting in to the grounds of micro-metrology. A term I have often heard is 3/5's of a gnat's d... to relate to a small unit of measure. At the other end of the scale we have the 'kin which is the standard unit of excess. As in it's too 'kin big/heavy etc.

[ettingtonliam]

On one construction site I worked on in the 1970s, the pipelaying gangerman's terms of measurement were 'a big bit' (about a metre), 'a bit' (about half a metre), 'a small bit' (about 100mm) and 'a small little bit' (about 10mm)

[Midland]

I think this thread ought to self destruct as there is no competition between the craftsman and the academic. The purpose of a university education is to teach people to 'think', as in theory, concept and discovery or invention, (or of the architect designing the unbuildable). The craftsman is first of all trained to craft as in potter, sculpter, author, artist and perhaps even a maker of things out of metal. As they age each of the two acquire the skills of the other because they work together. So, I have two degrees that took me six years but I have yet sharpen a drill that can drill a round hole. But I can read Don's book and grasp the complexities of the Stephenson's valve gear quite quickly. So I have a deal. If you come and sharpen my drills, I will translate Don's book into an improved gear for you but you must accept that I cannot draw it as I am not craftsman, yet!!!

Lets move on, Cheers David