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Member postings for Sam Longley 1

Here is a list of all the postings Sam Longley 1 has made in our forums. Click on a thread name to jump to the thread.

Thread: Static balance gadget
28/07/2020 20:33:03
Posted by Dave S on 28/07/2020 19:35:40:

I made the ends of my grinding wheel balance arbour the size of the largest bearings I had hanging around, IIRC they were about 15mm ID/30mm OD

I flushed out the bearings with wd40 to remove all the grease and then set them into v blocks.
That is sensitive enough to detect a a small out of balance on an 8” wheel, such that the spindle weights moved together make it rotate quite quickly.

Can you make the ends of your arbour small and do a similar thing?

Dave

Actually that seems to be a good idea

Compared to the other option it does not need one to align & level 2 rails. With the rails I was worried about them being inverted "V" shaped & dead straight as well as in line & perfectly level.

To balance the prop I was going to gently abrade/grind the surface on the back of the heaviest blade.

Edited By Sam Longley 1 on 28/07/2020 20:41:11

28/07/2020 17:32:00

The next question to the above is - If the wheels are 3mm th I cannot just mount ball races into 3mm steel discs. So presumably I need to fit a boss to each disc because it would be too much steel to turn . So what is the best way to fit a boss & then get absolute concetricity on 100-125 diameter & press fit the bearings.( Warco 250MVlathe) The bearings can be any diameter but I would expect something to fit 10mm bolts so I can fit them to the frame

I cannot fit the bosses & bearings & turn the final radius on a mandrel because the bearings would just spin. But i need to make sure that the wheels are true to the bearings. I am assuming ball race bearings or would something else be OK, ie would oilite bushes run freely enough

 

Edited By Sam Longley 1 on 28/07/2020 17:35:37

28/07/2020 17:23:33

I want to balance a 16inch diameter 3 bladed propeller from a launch. I can only do a static balance as I have no equipment to do any other sort of balancing. I guess it weights several Lbs

I intend to take the prop off the boat & turn up a temporary shaft/ mandrel about 400mm long. It will be 25mm with a taper to take the prop so I expect one end will be about 18mm diam. I will not need to thread it if the taper is a fairly good fit. I have not done such a taper before but will search youtube for guidance. Does not need a key

To do the balance I want to make a frame with 4 wheels. 2 overlapping each end. Each one on bearings & as free running as possible. I reckon about 3mm th & 100-125 mm diameter.That should be easy enough on my Warco 240MV lathe

What I am not sure is how far apart to put the centre of the pairs. If they are close together such that the tangents are fairly horizontal they may not rotate. if they are too far apart with the tangents almost vertical they will put a lot of side pressure on the wheels & increase friction then just jam.

So there must be an optimum angle for the 2 wheels to meet so that I get a good friction free rotation to balance the prop.(I think)

What is it?

Does anyone have any experience of static balancing & is this infact the right way to balance the propeller. I know this is an engineering forum but presumably some forumites have had to balance equipment at some time in their careers

I guess that in the water it rotates at max 3000 RPM. At tickover revs (800RPM) it shakes the bearing violently, but begins to run smooth once the engine revs pick up. I expect this is because the diesel engine runs smoother plus the water has an effect as well

 

Edited By Sam Longley 1 on 28/07/2020 17:25:00

Edited By Sam Longley 1 on 28/07/2020 17:32:46

Thread: Carbon fibre pendulum rod
19/07/2020 07:55:25

In model RC planes I use arrow shaft blanks. Stiff, cheap & 1 metre long

Edited By Sam Longley 1 on 19/07/2020 07:57:33

Thread: Excellent Service
10/07/2020 15:17:54
Posted by ChrisH on 10/07/2020 15:13:44:

(Don't like having to phone orders in, others can hear what's going on, no need for Senior Management to know all that goes on and see every invoice that passes the door - married men will understand!)

Chris

How sad !

Thread: What Did You Do Today 2020
04/07/2020 19:16:00

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

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,

smiley

Dave

 

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

04/07/2020 14:43:58
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!

Dave

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

04/07/2020 08:59:50

At one of the companies I worked for as a consultant I was given the task of interviewing about 30-40 candidates for quantity surveying posts. over a 12 month period. Nothing to do with my job, but they liked my technique.

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?

Even those experienced applicants applying for managerial posts at £80K+ PA were often stumped for a while

The answers were amazing.

Thread: Yipee the F1 is back on
29/06/2020 17:43:52
Posted by not done it yet on 28/06/2020 21:51:26:
Posted by Steviegtr on 28/06/2020 18:56:06:

Austrian GP on next weekend for any motorsport followers. Having a T.V & maybe SKY. would help. I know some members do not so this will be of zero interest to you.

Steve.

Why? We might just have a radio, you know. Doubtless the highlights will appear on Youtube (possibly even the whole race?). There will be reports in the papers - for those that read them. So please don’t assume or state obviously untrue statements just because you think yourself, and others with goggleboxes, are the only ones interested!

F1 ON THE RADIO ???? Crikey it is not exactly football is it (not that I would watch/listen to that either) But on the radio!! What do you do? listen to the Vroom vroom as they wizz past??devil Do they sound different to an enthusiast?

I find the pre race chat with Coulthard & co the best bit, provided E Jordan stays out of it that is. Might record the start & the finish. Then flick through rest as it is usually just a procession.

Still that being said , many years ago a relation of mine was absolutely ecstatic when his wife gave him a long playing record of the Isle of Mann TT motorcycle racing. He knew every motorbike by the sound.

Have to say for excitement, watching a you tube vid of Guy Martin lapping the IOM TT circuit has to be a bit squeeky bum stuff. The sidecars put on a show as well. Certainly puts a lap of an F1 circuit to shame.

I keep promising myself that next time I sail round UK, I will time it so I can moor up at the IOM & go & watch some of it.

I did find the Jim Clarke memorial museum at Dunns interesting. Mainly because I used to go & watch him race several times. A really entertaining driver, who did his best to put on a show for the crowds at Brands Hatch in his Lotus Cortina & his F1 car.

 

Edited By Sam Longley 1 on 29/06/2020 17:52:03

Thread: Hermes Parcels
25/06/2020 15:30:46

One of the local DHL drivers was excellent, even managing to notice a parcel addressed to the next village was in fact meant for me. He is an RC model plane flier & I suspect that if he had more time he would love to  have a look at my lathe & mill. Have not seen him lately, but they are still the best.

I have regular deliveries by pallet & the local pallet delivery company has the same driver for this area. He is excellent & invariably goes the extra mile getting the pallets- weighing up to 1 tonne- right into my garage, or shed. the odd tip does help though.

One company delivered my life raft & the 2 drivers would only carry the parcel 50% of the way up the drive & then dropped it there. Said they had " Met me half way" & that was that.

Edited By Sam Longley 1 on 25/06/2020 15:36:43

Thread: machining acetal
20/06/2020 13:24:16

As a beginner--This might be a stupid question

--But- (Not knowing how long the piece is) would it not be just as accurate to put the piece sideways in a 4 jaw chuck in a lathe & turn a flat Then turn it over & do the opp face which would be easy to do accurately then repeat for the other 2 faces. Would it come out square & parallel etc? Easy & quick to set up?

Assuming of course the OP has a lathe sad

Or is that totally wrong

 

Edited By Sam Longley 1 on 20/06/2020 13:27:55

Thread: Concrete Garages, Shelving and Catastrophe
17/06/2020 13:36:33

Bison Concrete produced over a million concrete garages for local authorities & stopped making them circa early 80's. When they stopped production at Chadwell, They sold the moulds, for peanuts, to Thurrock Concrete Ltd. who rented part of my builders yard. They then made spare parts for damaged Bison garages for LAs, which was a clever move as it was cheaper than replacing a full garage.

They did not use rebar as such but prestressed the sections with 1/4 inch diameter HT steel "wire". the pre stressing operation was quite technical & the one operation that the owner himself always insisted on doing. A broken overstressed wire, or errant anchor collet, could fly out many yards like an arrow. with serious consequences.

They always advised customers NOT to cut any pre stressing wires because, although they were held in set concrete they could pull back a little causing pieces of concrete to shatter outwards. Drilling a concrete panel can sometimes result in a long crack along the line of the wire, resulting in erosion of the wire at some later date.

I imagine that modern garages are made using the same method

Edited By Sam Longley 1 on 17/06/2020 13:45:37

17/06/2020 07:42:45

I have fully lined my concrete garage & in doing so have made lots of fixing points. I obtained some 25*50 *2.400 battens & some binding wire. I have some 8 inch steel fixers nips to twist the wire. I replaced the bolts to the joints in the concrete panels with lengths of stainless studding such that the ends stuck out 25mm both sides. This gave an anchorage point for the wire. One could do it by just slackening the bolts & working the wire behind them, but I have lots of studding left from a job so i just swopped it.

I placed the battens up the face of each joint. I passed the wire from one end of the studding round the face of the vertical batten back to the other end of the studding & twisted it really tight. I cannot recall if I did 3 or 4 per length This holds the batten really tight. The wire started to cut into the batten.

This then allowed me to place 25 mm celotex between battens,& face the lot with 4mm ply, up to 6ft high ( 1.5 sheets of ply wide)

However, back to your point. I can now screw things like my shelving (which is still supported at the front down to the floor) to the battens which are at 600mm centres round the garage.

 

Edited By Sam Longley 1 on 17/06/2020 07:53:31

Thread: Bandsaw advice
09/05/2020 15:49:13

Try Tuff saws. They are happy to advise & have informative website

Thread: Quick setting nuts
05/05/2020 17:39:33

deleted

Edited By Sam Longley 1 on 05/05/2020 17:59:46

Thread: Warco WM250v VFD. Start problem.
28/04/2020 20:01:44

I know that this is an old thread, but has anyone else had this ? Same model lathe.

Did you ever find the problem, because mine has been doing this for ages, but it is now getting worse, requiring it to be switched on off for up to 6 times on ocassions. There is a loud click when the green button is pressed. Other times it starts OK. But it has now begun to stop whilst turning. Even when doing quite light cuts. I have permanently removed the gear cover & byepassed that interlock. (wired it with a plug & adjustable stop for threading on the carriage).The chuck guard has been removed & I have rotated the bar as far as it will go so I do not believe it is the locks.

Unfortunately the lathe is against the wall & bolted on the cabinet & then to steel supports ( to raise it 9 inches) then bolted to the floor. So to get to the back is going to be a major job to get it off the base then off the cabinet etc. It would be handy to have some idea what to expect before beginning.

Was it just a loose connection? I have looked using a mirror & cannot see one

Thanks

Thread: Fantastic British engineering
23/04/2020 13:15:00

I have a friend who started as an apprentice at an engineering company in the UK. For the last 14 years he has been MD. They sell a particular product all over the world & he goes to exhibitions regularly. He sells to companies ranging from the Belgian navy & shipping lines etc as well as leisure sector. The product he sells has to be carefully designed (his skill) & properly manufactured.

When I asked him why he has his designs made mainly in China, he said the high quality machining was available & at economic price. The quality was exceptional. I asked why he could not get in the UK. He said that for larger items there were no facilities. He did buy smaller parts in the UK but he said that he only did it to show a lip service to the UK.

Generally UK subcontractors were such a pain to deal with, quality & delivery times were unreliable & he had more trouble getting stuff in the UK that he really found it so much easier going to the large number of firms in China.

Aside from that subject I suspect that there is another reason that the govt would be happy to allow manufacturing to go overseas. We have a strong green lobby in this country. There is a strong lobby to reduce our carbon emissions due to global warming etc( I should not say so here, but it is a scam, but that is not the subject of the thread)

By exporting our manufacturing capability overseas we also export our carbon emissions. It is a false preconception to say that we are reducing our emissions when we are having stuff made by a country that is building dozens of coal fired power stations every year to produce our goods for us.

But lower emissions look good to the gullible. The left are quite happy to be out of work & live on the dole, paid for by others, provided they do not watch their kids coughing their guts up in the streets due to exhaust gasses

It is a difficult balancing act

Thread: Lawn weed and feed. How much is 35g?
23/04/2020 08:04:25

Ask the local drug dealer to do it for you. He will probably bag it up in nice little bags for you if you ask him nicely. You could let him have some to bulk up his ganga as payment. Just do not let the local plod catch you driving home with the bagssurprise

Thread: Advice on Building Powerful Toy Cannon
20/04/2020 13:12:52

When I was very young a crowd of us kids cut some large "Y" shaped sections of trees & dug them into the ground. We built corrugated sheet barriers round them & bound on lorry inner tubes to them to form giant catapults. For ammo we went to the local rubbish dump, which was an old pit that was being filled in & forraged 3 inch reject stones.

Then we fired them at each other in massive battles. One side was in an orchard & one side was out in the pit. We were about 50-70 yards apart. The noise when the rejects hit the iron sheets was enormous and always raised a cheer from the attacking side. Surprising no one was injured .

Proper kids games in those days.smiley

Edited By Sam Longley 1 on 20/04/2020 13:13:06

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