By continuing to use this site, you agree to our use of cookies. Find out more
Forum sponsored by:
Forum sponsored by Allendale Jan 24th

What Did You Do Today 2020

All Topics | Latest Posts

Search for:  in Thread Title in  
Sam Longley 104/07/2020 14:43:58
796 forum posts
28 photos
Posted by SillyOldDuffer on 04/07/2020 10:14:27:
Posted by Sam Longley 1 on 04/07/2020 08:59:50:


One question I sometimes posed to degeree students was:-

I have to dig a hole of volume 1 million cubic millimetres. My lorries carry 8 cubic metres of earth. Allowing for earth bulking 25% when dug, how many lorry loads will I need?


A very odd question to ask either Quantity Surveyors or £80k Managers. What was your purpose in asking it?

Look at it from the point of view of the poor old candidate. He has to decide if the question is:

  1. testing mental arithmetic with an artificial problem using wildly dissimilar metric units, or
  2. deeply subtle needing careful analysis, or
  3. looking for a robust response to daft questions, as might be needed to rein in a bumptious apprentice, or
  4. seeking a polite response, as when dealing with a naive customer, or
  5. testing his negotiating skills.

Did getting the answer right or wrong make any difference to getting the job, and if so why?

I'm genuinely interested because selecting candidates is remarkably difficult and error prone: most methods don't work well. Fortunately, most people most of the time are adequately competent however they got the job!

The worst performers are untrained interviewers with no criteria - they look for Old School Ties, firm handshakes, and warm feelings. Assessment Centres are most effective. At them candidates are carefully put through several scenarios by a team over a few days, and assessed continually - even at lunch. Assessment Centres are very expensive, and although better on average they're far from perfect. They still miss exceptional talent and select men of straw for top jobs!


I was watching to see how they went about solving the problem & if they actually listend to the question.

I had a student who dwelled on it for a short while, then said "I know this seems funny, but I reckon that hole is only a few inches big" . He did not know the answers to several other questions but did not let it phase him.That I liked. I gave him the job. It was not long before he got promoted.

Another move was to sit by their right hand. Open a tape on the table across the front of them & slide it to 900mm look at briefly but obviously, it then extend it to 1200mm approx. lock it & lay it in front of them, then say " put your thumb nail on 90mm. 90% put their thumb on 900mm So you ask them how many mm in a metre. Then you ask the same question again & they still get it wrong

Bearing in mind they are asking for jobs as quantity surveyors they should be able to read a tape.

Another move was to show them the meeting room door & tell them the fire officer had condemmed it. The buyer was in an office 10 miles ago. Fill in an order form for an identical door but to be a fire resisting one.It was amazing how few could actually measure the door & get the size right. Some would forget the thickness. some would not  get the size right or  say it had to be F/C etc

I introduced this because I believe that managers should have the mindset to do practical things

The company MD interviewed a chap (wage £80k) & asked that question & he guessed the size. When asked what would happen when it was found that he had guessed wrong he shrugged & said " order another". The MD suggest that he not bother wasting time on further interview

I show them a picture of a dilapidated set of 8 store sheds & ask them to list the work items against a schedule of rates needed to repair up to a working standard. Most miss 30% of the items. Some could not work out the area of the roof.

No average human resources interviewer has the practical knowledge to ask those questions, so they never get asked, yet they are a major part of the job. I like to see how the applicant reacts. We need people who can solve problems on the fly not those that can just crunch numbers all day without knowing why

You have suggested that most applicants are competent. I beg to differ. I found many who simply do not tell the truth. One, for instance claimed to have a working knowledge of Excel spreadsheetd. But ask them what a macro is & the answer was " That is when you press some keys & things happen". I have tales of many similar replies.

I was looking to see if they understand the job & if they show that they have actually had the experience they say they have. If they can respond to the unusual & if they show the sort of confidence that is needed to work in a team. You can do an initial interview in an hour, then have a second one to meet senior management for the higher paid ones. Up to £45K it was just down to me. Followed by a job offer


Edited By Sam Longley 1 on 04/07/2020 15:08:22

SillyOldDuffer04/07/2020 16:31:31
6331 forum posts
1389 photos

Thanks Sam. I guess we were looking for different things in different contexts. I mostly recruited for the long term with an expectation that development would be needed. The main exception was contractors, who were expected to know their stuff.

Depends on the job, but when interviewing I didn't weight basic practical skills that highly. Most people can pick them up with training and experience; for example tape measures and photocopiers are both easily learned on the job. A Quantity Surveyor not remembering everything needed to survey a shed off the cuff wouldn't necessarily phase me either. Evidence people know how to find out and make progress is usually more important in thinking jobs than memory tests.

I'm amazed an £80k Management candidate was expected to order a Fire Door. That's emphatically not a management skill! Good managers rarely need practical skills, their job is to coordinate and organise the do-ers, not to sink into technical details themselves. Management involves a lot of guess work and accepting risk, which your chap demonstrated. Better to ask managers about Priorities, Resource Management, Strategy, Effectiveness and Organisation etc. Same is true in reverse: it's not a good idea to recruit Welders by asking them to explain a Discounted Cash Flow!

Leaders are another case again. Being a Sociopath is an asset! The bigger the lie the more people fall for it!

By the by, after a long career in IT, I'd have to think about what a Macro is, and would probably take a couple of pages to define them thoroughly. Beware of experts: I might find your answer in the "That is when you press some keys & things happen" class too. Is Excel VBA Turing Complete? Discuss. (Interesting question that might be asked in an IT Job, but mostly irrelevant, even to Excel Power Users!)

Glad I'm retired



Martin Kyte04/07/2020 18:01:17
2065 forum posts
37 photos

If they get as far as being asked to an interview they have the qualifications for the job. The interview seeks to find out what they are like as a person.We were looking for an instrument service engineer once. Short listed 4 out of around dozen. One of the practical things we did was put a 13Amp plug on the table along with a screwdriver and ask thenm what they made of that. One and only one picked up the screwdriver and took the plug to bits. He got the job. They all knew about electrical safety but that guy was confident enough to be curious.

regards Martin

Sam Longley 104/07/2020 18:19:22
796 forum posts
28 photos
Posted by SillyOldDuffer on 04/07/2020 16:31:31:

I'm amazed an £80k Management candidate was expected to order a Fire Door. That's emphatically not a management skill! Good managers rarely need practical skills,




I take your point but disagree in the context that we were looking for managers.I was actually retained by the company because of my high degree of practical knowledge. Even though most of my work involved contractual claims, I did spend a lot of time training, because they wanted me to take some of the trainees out on site to give them practical experience, which others could not give them.

I wonder what some of our older forumites might think about your comment about managers not needing practical skills!!!


Edited By Sam Longley 1 on 04/07/2020 18:20:12

Sam Longley 104/07/2020 19:16:00
796 forum posts
28 photos

I would have deleted my post when i realised the extended thread drift but the edit does not work. Is there anyway to correct that?

Sam l

Ian Johnson 104/07/2020 19:56:57
288 forum posts
82 photos

Have you ever made something for your workshop which took half an hour to make, and looks as rough as a bears backside, and then used it for years and years? I made a clamp for a small surface gauge/pointer

This is the old clamp. I made this for a small magnetic base out of a scrap piece of brass, a 1/4" unc bolt and a mystery knurled nut from somewhere. Using a file, a junior hacksaw and a hand drill. Works okay but It is sloppy and rough. I use it regularly on the manual mill, because I don't have digital read out, it comes in handy to remember where my datum points are.

pointer holder old img_4883.jpg

The day finally came when I just had to make a new one. One that looked pretty and worked like it should do. So I found a piece of 3/8" x 3/4" mild steel bar for the main body, and used silver steel for the nut, sleeve and bolt.

This is the new one. I prefer straight flutes for the grippy bit, I think they look better than a knurl, this was done with a handwritten program for 18 flutes on my KX1 CNC.

pointer holder img_4882.jpg

I think this new one will last just as long as the old one, and is much nicer to use. Just mulling over whether to chemically blacken the pieces or leave them blingy?


BCPROF04/07/2020 20:08:46
141 forum posts

Does the lack of a requirement of practical skills by management and the appreciation of what is needed to complete a task go some way in explaining why so many of out civil engineering projects are way over budget and fail to be completed on time ?

martin perman04/07/2020 20:08:58
1876 forum posts
78 photos
Posted by Sam Longley 1 on 04/07/2020 18:19:22:
Posted by SillyOldDuffer on 04/07/2020 16:31:31:

I'm amazed an £80k Management candidate was expected to order a Fire Door. That's emphatically not a management skill! Good managers rarely need practical skills,



I wonder what some of our older forumites might think about your comment about managers not needing practical skills!!!

Edited By Sam Longley 1 on 04/07/2020 18:20:12

+1 for the above, I served my time on a maintenance dept where the management were all ex fitters, electricians etc when you got given a job you knew they knew what they were talking about and they helped you through if you had issues, my last job was made difficult because my educated manager had no idea what the problems were and didnt want to know and only wanted to take the customers side to keep them sweet and I and others were only lambs to the slaughter if we couldnt sort the problems in an impossible time.

Martin P

IanT04/07/2020 22:11:28
1614 forum posts
151 photos
Posted by Ian Johnson 1 on 04/07/2020 19:56:57:

Just mulling over whether to chemically blacken the pieces or leave them blingy?


Most definitely leave them Blingy!


Ian Johnson 104/07/2020 23:57:56
288 forum posts
82 photos

Yep I agree, I'll leave them blingy! Good job my workshop is relatively rust free!

Bazyle05/07/2020 11:57:20
5479 forum posts
206 photos

Why not make a knew nob for the old one? cheeky

Ian Johnson 105/07/2020 12:52:33
288 forum posts
82 photos
Posted by Bazyle on 05/07/2020 11:57:20:

Why not make a knew nob for the old one? cheeky

Aha! Good idea! But then all the other pieces would look rubbish and for the next 20 years I would be looking at them wishing I had made something that looked pretty laugh

Henry Brown05/07/2020 18:13:35
296 forum posts
83 photos

Nice job Ian, great knob disgust


I have been given 6 used heavy duty rubber mats from a stable, about 6' x 4' each. My workshop floor has been made up of odds and ends of various rubber mats so far, today I took the old ones out and with a little help from "The Enemy" we managed to fit two of them. They are very about 3/4" thick and very heavy, I found the best way to cut them was with a jigsaw with a very coarse blade. I'm quite pleased with them now they are down despite the slight aroma of horse...

20.07.05 new floor mats.jpg

Iain Downs05/07/2020 18:28:59
688 forum posts
622 photos

I have had a cracking weekend and a particularly good Sunday. Something bad is due to happen ...

First thing this morning, I found out why my Arduino power feed code wasn't working - after quite some time puzzling. It turns out that Aaduino interrupts and float point don't play nicely. Migrated to long integers and it just worked! I now have all the bits I need for the power feed, though sadly, I found I had no heat shrink when I came to solder up the motor connections. Amazon prime to the rescue. Perhaps tomorrow.

Next an old client came round. He's had this idea for a product and had 3 goes of getting hardware which worked - I first wrote some software for him in 2012. This time was the 3rd time of asking and we managed to get a good result for the first time! Software again, I'm afraid, but that's actually my competency!. Those of a similar disposition will be thrilled to know that it was about dealing with raw input with USB HID devices. Ugh.

Finally, and this is closer to proper engineering, I finished off fitting the newly received DRO on my mill. And it actually worked!

to be fair, I've only put X and Y on and am waiting for a bit of ally for the Z, but that shouldn't give me any problems. In truth the spindle DRO is of much more use.

I will report on that in more detail in one of my other threads.

I did think about trying to mount the power feed tonight, but two things put me off. First (and most important), if things seem to be going well, stop. It's just the universe's way of setting you up for a fall!

Secondly, I decided that some celebrations were in order and I've made it a rule not to mess with rotating machinery after a glass or two (wimpy, I know and 20 years ago. I wouldn't have cared).

So still a happy chappy and REALLY looking forward to working out how the hell I can use the DRO (the manual is close to English, so I reckon I can interpret).


Paul Lousick07/07/2020 11:18:48
1544 forum posts
579 photos

The antique engine and model clubs that I am a member of are still closed because of the lock-downs and it's getting a bit boring at home on my own so decided today to go on another One Man Rally with my traction engine.



SillyOldDuffer07/07/2020 12:26:40
6331 forum posts
1389 photos
Posted by Iain Downs on 05/07/2020 18:28:59:


First thing this morning, I found out why my Arduino power feed code wasn't working - after quite some time puzzling. It turns out that Aaduino interrupts and float point don't play nicely. Migrated to long integers and it just worked! ...


Probably not simply that floating point and interrupts don't play nicely as such, more likely it's a timing issue. The thing about interrupts is they suspend whatever the processor is doing, jump to new logic, and then restart the original process. If the original process remotely time sensitive, then it can be severely disrupted if whatever the interrupt routine does takes too long. Particularly confusing when an interrupt takes so long it's interrupted itself!

The general rule is to ruthlessly minimise the work done during an interrupt, getting out of it as fast as possible, ideally within microseconds. One way of doing this is to have the interrupt set a flag telling loop() to do the work outside the interrupt.

Floating point is done in software on an Arduino and - in computer terms - it's painfully slow. Arithmetic done with integers is much faster, but adds other booby traps like overflow. Floating point can be used in interrupt service routines, but keep a close eye on how long it takes. Same is caution with any other time consuming logic like waiting for serial input or a device to respond.

Good job solving it. Interrupt problems are very hard to debug because they're usually time related and the code looks fine. Event relationships are wrong rather than the program logic. One way of pinning them down is to put an oscilloscope on an output pin (or two) and toggle them with debug code when things are supposed to happen. If the oscilloscope shows toggling unexpectedly, suspect something taking too long in the code is disturbing the 'when' rather than the 'what' logic.

One advantage of the Nucleo compared with Arduino is they do floating point in hardware, pretty much as fast as integer arithmetic without the booby traps.


Howard Lewis07/07/2020 12:56:35
3615 forum posts
2 photos

One thing that no one seemed to mention in the discussion about managers for a practical environment.

If the manager does not have an appreciation of the process, he is a lamb to the slaughter with anyone keen to swing the lead..

"Can't do that, the toggle won't clear the widget arm" and he doesn't know enough to say "Stop talking nonsense. Do it this way. Shouldn't take you more than twenty minutes" BUT it has to be correct!

The word soon goes round that the boss knows his stuff, (even if it really isn't in detail ) So fewer try it on with him, because they are not sure just how much he does know..

And if he keeps his eyes and ears open, he will learn lots more useful stuff for the future.

Once I had a boss who, among many other things, didn't know what the function of bearing was. Full of management speak, but practically useless. He was a nice bloke, but an embarrassment!


Paul Lousick07/07/2020 14:22:25
1544 forum posts
579 photos

"If the manager does not have an appreciation of the process, he is a lamb to the slaughter"

I worked for a company that enlisted a manager like that. It was a successful multi million dollar business but because of bad decisions and not knowing what he was talking about, sent the company broke.


Emgee07/07/2020 15:02:41
1725 forum posts
232 photos

Nice running engine there Paul, not a lot of traffic to contend with.


Iain Downs07/07/2020 17:12:07
688 forum posts
622 photos

Dave - After working out that it was the floating point, it still wasn't quite working and I ended up creating a new sketch and mucking around with it - with a scope attached to one of the pins.

I was surprised at how poor the timing was. From memory (it was last night now) with nothing happening apart from an interrupt on a timer (PORTD ^=D00001000 or something) I couldn't get more than about 250kHz or so as the blink - so 500K calls to the interrupt per second. 32 clock cycles. Hmm. Not that bad, I suppose, when you do the sums.


All Topics | Latest Posts

Please login to post a reply.

Magazine Locator

Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!

Find Model Engineer & Model Engineers' Workshop

Support Our Partners
Eccentric July 5 2018
Eccentric Engineering
Subscription Offer

Latest "For Sale" Ads
Latest "Wanted" Ads
Get In Touch!

Do you want to contact the Model Engineer and Model Engineers' Workshop team?

You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.

Click THIS LINK for full contact details.

For subscription issues please see THIS LINK.

Digital Back Issues

Social Media online

'Like' us on Facebook
Follow us on Facebook

Follow us on Twitter
 Twitter Logo

Pin us on Pinterest