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Messages - GuyFawkes

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1
General Discussion / Re: High end Flashlights/torches
« on: June 20, 2009, 03:18:39 PM »
Let me know when you start shining it on the moon, I'll set up the telescope and watch for it  ::)
Stan

If I get one, and if I point it up, look for me in Gitmo, not the moon.

3
General Discussion / Re: The Crash Course
« on: June 20, 2009, 02:37:04 PM »

Promoting the general welfare didn't start as welfare payments. General Welfare means to benefit the entire nation. It was intended as a limit to prevent 'specific benefit to a certain group' Building roads or dredging a canal was prohibited for the federal Gov't because the benefit was for that region, not the nation in general. National health care would be specifically prohibited because it benefits individuals at the expense of tax payers.


Bzzzzt.

Wrong.

Social Security has nothing to do with providing financial security to individuals.

Social Security has everything to do with providing Society with security from individuals.

Here in the UK Social Security means nobody has to starve, nobody has to live in a cardboard box, nobody has to sell their liver to pay for their kids insulin.

As a result, nobody has any legitimate excuse to prey on other individuals, eg society, to live.

Social security makes stealing food from your plate a morally justifiable punishable offence.

Since then of course there has been mission creep.

4
Engines / Re: Lister-Petters TR2 or Changfa clone?
« on: June 15, 2009, 03:02:55 PM »
The TR2 is a modern engine design and being twin cylinder the bores are smaller so burn more efficiently  , this means that it will run at part load without any issues.

smaller bores more efficient?

Load of tosh.

The relationship between swept and head volume and swept and head surface area is not linear.

Volume of a cylinder is piR2H
Area of the sides of a cylinder is 2piRH
Area of the flat piston top is piR2
Area of hemi head is 2piR2

Let's take a 10 cm bore and 12 cm stroke

Swept volume is 3.14 x 5 x 5 x 12 = 942
Swept area is 2 x 3.14 x 5 x 12 = 376.8

942 / 376.8 = 2.5:1 volume to area ratio

Lets take a 5 cm bore and 6 cm stroke

Swept volume is 3.14 x 2.5 x 2.5 x 6 = 117.75
Swept area is 2 x 3.14 x 2.5 x 6 = 94.2

117.75 / 94.2 = 1.25:1 volume to area ratio

Plus, the smaller bore with a smaller swept volume will require 942 / 117.75 = 8 cylinders to develop the same swept volume.

So you can have your smaller bore with far lower swept volume to swept area ratio, far higher piston ring / liner friction length, far more journal friction, and you think this is somehow going to be more efficient than the larger bore.

Never, not as long as you have a hole in your ass.

The ONE advantage of the smaller bore as in this example is your 8 cylinder engine COULD be made, not WILL, but COULD be made with lower total piston and con rod weight than the big single of the same swept capacity.

The ONE advantage this gives you is you can rev the tits off it, pump more air in any given unit of time, thus burn more fuel, this achieve higher specific BHP, this WILL NOT equate to greater efficiency.

Even at partial load, a worst case scenario, the big single will hammer the 8 cylinder engine working at peak efficiency, when it comes to efficiency alone.

Small bore engines NEVER beat big bore engines of the same capacity and similar design for efficiency, to claim otherwise is to simply ignore Physics and invoke greater than unity efficiency or zero point energy of some other bollocks.


---------------


forgot to do this sum.

big single 10cm bore x 12 cm stroke = 8 cyl 5cm bore x 6cm stroke in swept volume.

quite apart from area losses.

PiD = length of a circle, eg piston ring.

Single has one 3.14 x 10 = 31.4 cm length of top scraper ring

8 cyl has 8 x 3.14 x 5 = 125.6 cm length of all 8 top scraper rings

repeat and rinse for all rings, then add 10% frction due to extra losses in a small bore vs big bore engine, small bores start to burn oil at low hours...

5
Just picked up a genuine Lister manual for SOM sets dated 1969 covering 6/1 & 8/1 sets. There is a comment stating that the radiator cooled versions are rated at 5% less output at the generator then the tank cooled version. Must be that the 70 gallon tank cooled version has more heat removal capacity than the rad version.

6 bhp x 746 watts = 4,476 watts

5% of 4,476 = 223.8 watts

200 watts / 1/3rd hp is about right to drive a fan at 1,000 rpm.

6
General Discussion / Re: Way off topic Mini bike Discussion
« on: June 12, 2009, 09:13:44 AM »
Go down to the A&E (ER in american) and ask them what they think of mini-bikes and quad bikes.

There was a recurring theme in the accidents involving quad bikes. One 48-year-old employee was killed when the ATV he was riding overturned. He lost control of the vehicle as he approached the farmyard. The front tyres were worn and were about to be replaced during a vehicle service, though the worn condition of the tyres was not thought by the vehicle examiner to be a significant factor in causing the accident. The driver was not wearing any form of protective headgear and sustained fatal head injuries when the vehicle overturned.

A 52-year-old self-employed farmer died when his quad bike ran head-on into a wall. He was riding a quad bike loaded with fencing posts across a slope. It is assumed, since there were no witnesses, that the posts moved, causing the farmer to lose control of the vehicle. He was not wearing any head protection. A 61-year-old self-employed farmer was killed when he fell from a quad bike, which overturned after he rode it up a steep field and accelerated over cattle ruts. The front wheels lifted and the acceleration caused the bike to rear up and overturn. He was not believed to be wearing a helmet and suffered head and neck injuries, as well as a broken elbow.

A 43-year-old farm worker was discovered underneath a quad bike. He was using a quad bike to bring in cattle for afternoon milking and was not wearing a helmet. He died from head injuries.

A five-year-old child was hit and crushed against a gatepost by an ATV. Her mother was tending a horse in a field, accompanied by her two children. She entered the field with her youngest child, leaving the ATV's engine running. It appears that her other daughter may accidentally have lent forward and operated the accelerator, causing the ATV to drive forward, hitting the youngest child and trapping her against the gatepost.

Fortunately, not every quad bike mishap ends in a fatality, but statistics show that minor injuries have also risen exponentially with the popularity of the ATV. In 1998, 1,200 patients visited Accident & Emergency centres across the UK because they had hurt themselves on a quad bike. By the turn of the century that number had reached 3,200, and by 2002 it was more than 4,200.

"The HSE does not release A&E figures any more, but it makes sense that the number will have grown since then," said Roger Vincent, a spokesman for the Royal Society for the Prevention of Accidents. "The greatest problem with quads is that owners will drive them too fast on uneven terrain without first learning the basic skills on flat, open terrain. Drivers must remember that this is a professional piece of equipment, rather than a toy to tear about on with a friend on the back as though they are on a fairground ride."

Roger quoted the example of Thomas Crombie, a father of two, from Lanarkshire, who died in an accident on a quad bike bought only two hours earlier. The 37-year-old suffered fatal injuries when the 200cc machine struck a brick pillar. He was driving quickly around an industrial yard when he attempted a tight turn. The bike turned over and he was thrown head first into the brick pillar. He was not wearing a helmet.

ATV manufacturers recommend that their customers sit an EASI (European All-Terrain Vehicle Safety Institute) test when they buy a quad bike. For more information, visit www.quadsafety.org


7
General Discussion / Re: GM bankruptcy !!!
« on: June 11, 2009, 06:55:24 PM »
I'm afraid you are all right where it doesn't matter, and all wrong where it does matter...

I've blogged about this, but the basic points are these.

The 4th estate (look up Louis XVI) is the Press, things went wrong when the mechanical governor of the government machine, namely the 4th estate, started to abandon their posts and take up roles within the 3rd estate, government.
(1st estate is clergy, 2nd is nobles)

Now the 4th estate in the UK has maybe 12 actual journalists, but that job is now called "investigative journalist" and those 12 or so stand zero chance against the barrage of flacks who simply wait in line for the PR handouts and print them verbatim.

differentiating "investigative journalism" from "journalism" is EXACTLY like saying this city has 2,488 detectives, and 12 "investigative detectives" and wondering why you have a crime pandemic, with 2,488 detectives just sitting in the precinct waiting the criminals to turn up with ready prepared pdf documents and power point presentations and signed confessions.

the 4th estate abandoned its post because we the people prefer fantasy to reality, and it doesn't matter how rich or powerful you are, you still prefer fantasy to reality, had a girl here last week being offered the career break/opportunity of her lifetime, and she starts wittering on about how so and so in reality tv programme the apprentice would handle it.

told her straight, what the fuck are you doing wasting your time on that shit and in doing so GIVING THEM A JOB when you have this opportunity in your fucking face right here and right now.

nobody held a gun to anyone's head and made them build, or buy, a hummer.

in a way it sucks, I was always an olds man myself, delta 88/98 was it for me (old man liked buicks) when it came to yank metal, but it's gone, dead, let it die.

don't kid yourself that the economic bomb has dropped and now all we have to do is survive the fallout, that isn't what happened, like the 4th estate abandoning its post what happened here was a sea change, as big as any of the big changes in the past.

You think the people living through the Industrial Revolution in England realised they were living through the industrial revolution? No way. That shit is only visible with 20/20 hindsight maybe 50 years later.

Only two words you need to know

"indentured servitude"

190 years ago an hours drive from here we had the tolpiddle/tolpuddle martyrs, in 1834, George Loveless, a FUCKING FARM LABOURER, long before anyone had heard of modern education, upon being sentenced, wrote;

"God is our guide! from field, from wave, From plough, from anvil, and from loom; We come, our country's rights to save, And speak a tyrant faction's doom: We raise the watch-word liberty; We will, we will, we will be free!"

I don't know many Managers in 2009 who could be so eloquent, which says a LOT about the lower working class stiffs, which explains why the 4th estate was allowed to abandon its post so easily... we have systematically and deliberately been driving down the level of education (reeding and riting ain't the same thing as being educated) of the common man.

There is NO DIFFERENCE, intellectually, between a nigerian 419 scam and a sub prime mortgage, and frankly there is no difference in the level of stupidity and lack of common sense that it takes to enter into either one... either way, you richly deserve to lose everything including your shirt.

the cheese eating surrender monkeys, without whom the USA as we know it would not exist, were the last people to effectively make these scams carry a suitably deterrent price, and put large parts of whole classes to madame guillotine.

existentialism is another good word, everything material is an illusion, a concept that those carry debt will become increasingly familiar with in the coming years, as they find that there is not a single thing that they own that will not be taken away as soon as they default on their tithes and taxes.

8
General Discussion / Re: GM bankrupcy !!!
« on: June 01, 2009, 12:12:09 PM »
Just heard the news here in the UK of GM filing for bankrupcy ! That is truly shocking ! Out of all the bad news during this global financial crisis that has had more impact with me than anything else. I'm aware that they were in BIG trouble and this was almost expected but to actually hear of the one time biggest auto manufacturer in the world collapsing into a worker / government coop is epic !!

Whats the mood over there guys ?

Biggest auto maker in the world? At one time they were the biggest company on the planet.
Total assets last year were 91 trillion US$

Don't be fooled by the dead cat bounce, the economy has a long way to go yet.

9
Everything else / Re: Pulling a pulley
« on: June 01, 2009, 02:08:44 AM »
ignore this at your peril.

pulleys are cheap and easy to make, shafts are not.

bent / damaged shafts are easy to repair

cut the pulley off, save the pieces.

disassemble the head

repair the shaft as required, then do what is required as far as bearings / bushings replacement pulley

this is a piss easy but time consuming job to get RIGHT, and piss easy to get wrong and make a mountain out of a molehill by trying to save a fucked pulley on a riveted shaft end.

engineering principle, until you extract the bare shaft, you cannot measure it for deflection, damage and wear.

engineering principle, until you can measure something, you are throwing sticks in the dark.

engineering principle, to get from throwing sticks in the dark to knowledge, perform as few irreversible actions as possible, and any you do do, make them cheap and easy to replace with new.

HTH

10
Everything else / Re: Lathes and stuff
« on: May 30, 2009, 11:27:34 AM »
About '85 I saw a guy dragged into a (ship) shaft lathe running at 12 rpm, synthetic (not cotton) overalls so they didn't tear, thing was, it was powered by a big geared down flywheel weighing mebbe 5 tons, to get perfect steady feed RPM, so you couldn't just stop it in microseconds.

That's where I learnt the principle that while "accidents" may take several seconds to run their course, there is literally one thousandth of a second to change state from avoidable to inevitable. Once that thousandth of a second event has come to pass nothing can stop it.

To the OP, if you are in the UK I have those videos on DVD, mill and lathe sets

11
Everything else / Re: Lathes and stuff
« on: May 30, 2009, 11:02:20 AM »
It looks like I've scored a nice Harrison L5A lathe from the workshop next door, for reasonble money (they only use it for winding reels of welding wire!) - so now I'm looking forward to getting into a whole world of machining ;D

First job will be to do something with my extremely dodgy exhaust system which is currently held together with an oily rag... but I'm hoping I'll be able to use it to renovate the bore & crankshaft on my 2nd engine (both are rusty), and I'll probably need to machine an entire new shaft for the startomatic alternator, as the current shaft is badly bent.

Also, as it's a fairly old machine ('50s to '60s vintage), I'm hoping I can cut Whitworth screws/nuts with it, if needs be...

So... I'm looking for a good "learn to lathe" resource - any recommendations from the panel?

come into this late, and been busy elsewhere...

basically a lathe is a machine that rotates the work while keeping the tool fixed, and basically a mill is a machine that rotates the tool while keeping the work fixed.

Before you go any further, take a look at
http://picasaweb.google.co.uk/fasand.words/LathesCanKill#
make yourself look at it at some length

now, a small hobby lathe or mill can't do that to your body, but it can do it to hands, fingers and eyes.

spend an hour or two with thumb and first two fingers of your main hand gaffer taped to the palm to simulate losing them.

*EVERYONE* who has NOT had or been present at a machine tool "accident" will think I am exaggerating the safety aspect.

OK, that out of the way.

1/ carbide / HSS debate.

Carbide is for production environments with very rigid machines, loads of spindle torque, where high material removal rates are the difference between trading and going bust.

HSS can cut anything carbide can, plus you can sharpen or harden it at home, it is NOT great for high material removal rates, but so what in a hobby environment. HSS can be posted out and CNC sharpened and posted back for a couple of bucks a tool if you don't have a suitable tool grinder and skill.

HSS is homogenous, the whole thing can be ground to be a tool, no brazed tips, no screwed in inserts, nothing to break and fly off, nothing to buy, nothing to go wrong.

2/ the lathe chuck key is something that exists in one of two states, it is superglued to your left hand, or to the tool rack, it is never, ever, ever left in the chuck.

3/ emergency stop bar triggered by your hips, plus the button.

4/ never ever ever do any chuck adjustments when the lathe is rotating OR has power going to it.

5/ set up the things that can go wrong FIRST, eg the trip to stop the tool feeding into the chuck.

6/ don't forget on a lathe the crossfeed is adjusting radius, not diameter, if the object is 4mm too large you only need 2mm of cross feed radius to get 4mm diameter.

7/ ensure the cutting edge of the tool is bang on centre height, and at the right angle to the work.

8/ if you get juddering "more feed, less speed" eg slow down the RPM and / or up the feed rate.

9/ go and look at that video again

I *HIGHLY* recommend you splash the cash on these
http://smartflix.com/store/video/574/Professional-Machine-Shop-Course-Vertical-Mill

HTH etc

12
General Discussion / Re: Cars again.
« on: May 27, 2009, 12:43:46 PM »
Reminds me of the old saying.

"You buy the horsepower, and drive the torque"

My old citroen might do 100mph, but you wouldn't enjoy it. But it will do 80 all day and night, and it is possible to do 80.

I don't "get" owning a 160 mph vehicle unless I could actually do 140 mph at least 10% of the time.

In bikes, because it is doable, anything over 110 mph gets geared down at the back sprocket to get longer legs and more mpg, makes em slower off the line and slower top end, but far nicer to ride, far more reliable, and far more mpg.

100 mph here is an automatic 12 month ban.

90 is likely 6 points (get 12 in 3 years and automatic ban) or maybe 9 and a fine.

80 is potentially 3 points.

This is all in NSL (national speed limit) 70 roads.

On other roads with lower speed limits it gets worse, 40 in a 20 is a lot lot worse than 90 in a 70.

speed limit on 6 foot wide country road with stone hedges and cowshit not otherwise limited is 60

13
General Discussion / Re: Cars again.
« on: May 27, 2009, 12:04:06 PM »


I wasn't talking about a bike I am talking about my Daily Driver an Infiniti G37 coupe with a six speed manual transmission

Carl

just had to google that, trust the nips to put a 6 speed in a car, notice you don't mention mpg tho...

Back around 85 I drove a vette with a hopped up big block 454 and 4 speed manual from germany to spain, on the autobahns that bitch came in to its own, held it at over 150 mph for over an hour, it would have gone faster but the chassis / my nerves weren't up to it, got to france and spain and it was raining and wished it has the auto trans, way way way too easy to light up the back end and skid, had to stick it in a high gear and pull between 500 and 1000 rpm, way below the power band to control is safely.

reminded me a lot of the early porsche 911 turbo, great on the autobahn, complete fucking crap on twisty wet stuff.

Fact is I've found long distance is all about average speed, drive from here to greece and (quite apart from the weird tarmac they use in greece, no grip at all) when it comes to cars a decent pug 400 series or merc 300 series diesel is as fast as anything, and when it comes to bikes a shovel with a decent seat and 5 gallon tank is as fast as anything, stopping for fuel or to stretch your legs really kills that average speed number.

Boats teach you that I guess, you'd be surprised how far you can go at 8 knots if you're doing 8 knots 24/7... you think, pah, 8 knots, I can walk at 4 or 5, that's pathetic, but it works out at 1,344 nautical miles a week just by not stopping or slowing down.

For those that say 470 miles in a day is no big deal, much of the a30 / a 303 is not dualled, single lane each way, twisty roads through villages and up and down hills, then m3 for a bit, roadworks and 50 mph average speed cameras, then m25 for a bit, always accidents or something to slow you down, then m26, all the dover traffic, then cut across the 299 etc back roads again, then do it all in reverse.

it is a LOT harder work than sitting on a genuine motorway / autostrada / autopista / etc.

dunno what the 0-60 time is for my 1.9 diesel, but I don't cane things, change up at 1500 revs, so prolly something stupid like 45 second, also don't brake hard, brake soft and early, fast ain't fast, smooth is fast, and smooth is where you get your mpg from.

I see it all the fucking time, people will charge across town because fuel is 2 pence a litre cheaper, with a 40 litre tank that just saved you about 60 p assuming you fill up at a quarter tank, and you can save four or five times that amount by driving smoothly....


14
General Discussion / Re: Cars again.
« on: May 26, 2009, 02:10:39 PM »
Guy,

Great fuel mileage numbers, don't take offense, but, I had to chuckle a little when you said it was pegged at 85. Normally I am just shifting into 4th gear at 85, and still have two gears left.


Carl

1/ yeah, I've got bikes too.

2/ the national speed limit here is 70 mph, it is flatly impossible to sustain any speed much in excess of that for any reasonable period of time, you lose your licence, I have found that if you drive carefully and steadily and transparently and leave plenty of room etc etc etc you can push the speed limit by 10 mph and cops won't pull you, but they have to see you and think "he is driving safely"

3/ that mpg figure is at that AVERAGE speed of 78mph... had a 74 shovel that would do 70 mph @ 70 mpg with a 44t rear sprocket, current bike (also a v twin) will do similar, the old Z1 and XZ11 would do mebbe half of that.

15
General Discussion / Cars again.
« on: May 25, 2009, 04:26:18 PM »
Just done some driving, Exeter in Devon to Canterbury in Kent and straight back.

Total distance 470 miles.

Total journey time inc stops 6 hours.

Average speed 78.3 mph, actual speed mostly pegged at 85 mph.

Total fuel consumption in money £40

@ £1.04 a litre that is 38.46 litres.

That is 12.22 miles per litre.

@ 4.54 litres to the imperial gallon that is 55.48 mpg

@ 3.785 litres to the US gallon that is 46.35 mpg

These mpg figures are at 80 mph on A roads and motorways, up hills and down dales, oh yes, drivers window and sunroof wide open which doesn't help the drag any.

Car is a 1995 Citroen Avantage estate with 4 pot naturally aspirated 1.9 litre diesel, I paid 400 quid for it.

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