|Thread: Lathe levelling|
As a non trained mech engineer, I was networks and telecomms, I do wonder if it's really necessary to have the bed level in order to turn parallel, unless we are talking large lathes.
I can obviously understand it on larger industrial stuff, where headstock and tailstock ends are on separate pillars; I've even read of very long dockyard lathes whose accuracy depends on the state of the tide.
For most smaller stuff, built onto a rigid cabinet, surely it's really twist in the bed which is important, along with tailstock alignment.
How could a ship's lathe turn parallel unless it were in dock or the doldrums.
|Thread: Record no 1 vice jaws seized - removal?|
Normfest Oxim Ultra seems to work as well as most things I've tried as a penetrating oil, as does the Lidl one, though the latter only turns up occasionally.
Also worth a try is a 50/50 mix of ATF and acetone.
One I've not tried it yet, though I now have some in stock, is tincture of iodine.
I saw that one advocated on a British Motorcycle group on Facebook.
I too used an impact driver bit, which I re-ground previously to have a shorter spade part, tightened in the jaws of the vice and with a large spanner.
If anyone is planning on replacing the jaws with new hardened ones, drop me a PM as I know someone who makes them to order. Record No 1s might be a bit small to be cost effective though
Edited By peak4 on 23/03/2020 12:54:47
|Thread: ventilator production coronavirus|
I would suggest it's not that easy, as modern ventilators are exceedingly complicated.
Germany ordered bucket-fulls some time ago, as did one or two other countries, and have allegedly managed to find some extra (Spanish) nurses from somewhere.
For some reason, we seem to be lagging behind many other governments in a variety of ways.
This Financial Times link contains an embedded letter which sheds some light on the more modern kit.
Essentially, as well as the kit, you need the staff who know how to use it.
I have no idea of the authenticity of Dr G's comments, but they do provide valuable explanation, assuming they are valid.
For the record, I am not an NHS ICU consultant in the South East of England... But if I were to imagine having done ICU since 1986 I might make some observations:
The old ventilators were essentially mechanical bag squeezers that inflated the lungs and then paused to let the gas out, before repeating the cycle. They had little sophistication, but meant that a person did not have to physically squeeze the bag, unlike the medical students who were enlisted to do this in 1952 during the polio epidemic in Copenhagen.
In the early 1980s we were ventilating patients after long operations, cardiac operations, head injuries, sepsis and the like. The key point is that the lungs were not the primary cause of the need for intensive care. Indeed, if the lungs started to fail, with Adult Respiratory Distress Syndrome, as it was called then, the patients usually perished. It was during the 1980s that more sophisticated ventilators were developed. We started to get Siemens machines which allowed alterations in the timings of inspiration and exhalation, they also allowed us to put positive end expiratory pressure into play. This meant that the patient would breathe out against resistance. The effect of this is to hold the tiny airways open and the alveoli, and to push fluid back into the circulation instead of having it sitting in the lungs and reducing oxygenation.
These machines are now the norm. They are smothered with sensors and we can measure most things and record changes that allow us to adjust the therapy. For example we can calculate lung stiffness and how it is changing with our therapies. We cannot do this with bag squeezing.
The sensors make the process less dangerous. If we get it wrong, the ventilator can cause barotrauma. At its most extreme we blow a hole in the patient's (diseased) lung and then we have a tension pneumothorax, which is rapidly fatal unless we stab the chest and insert a drain to allow the lung to re-expand. More often, the barotrauma causes microscopic damage that delays or prevents the sick lung from healing. The sensors also alert us if the tubing kinks or disconnects. Unchecked these simple things are quickly fatal.
So, to run a patient with acute lung injury/pneumonia as their primary diagnosis, to keep the oxygen going to the vital organs, we need all the sophisticated settings and sensors and alarms. We also need a highly-trained ITU nurse who can operate the machine, take the readings from it and alert the ITU doctor to adverse changes. When we introduce new ventilators, it takes several weeks for our nurses to become comfortable with them (think airline pilot and new aircraft type). We start them on simple cases where the ventilation settings are basic and the patient is not needing a variety of drugs by infusion and other time-consuming tasks. Once the nurses are happy with the new ventilators, we start to use them on the sicker patients; the nurses are, by now, more reflexive in their use of the ventilators.
So, imagine the perfect storm of non-ITU nurses being put in charge of a desperately sick patient who is attached to a ventilator that none of us has seen before! Mark my words, there are no spare ITU nurses. We will have to start using nurses who have not got the extra qualifications. They will need to be given reliable machines with good ergonomic fail-safe designs.
(I still remember two patients that we killed in the 1980s simply because their ventilators were not properly assembled; the modern machines would alarm and actually describe the fault on their displays.)
Currently all of our machines are German or Swedish. They have undergone years of development so that the alarms give us information according to urgency, the controls are intuitive, every kind of ventilatory mode is possible. They have been tested and CE marked and the companies take responsibility for their machines, through produce liability.
If the government introduces the Johnson Mk 1, or it arranges for a digger company to copy established ventilators, will Matt Hancock assume responsibility for any deaths due to malfunction, or due to our nurses not knowing about the machine's foibles? At present, we may get these machines (possibly) but we would be very unlikely to use them without assurances from the NHS that individual nurses and doctors would bear no responsibility if the machine malfunctioned and destroyed a patient's lungs, or simply failed to deliver 16 breaths per minute 24/7.
Without the nurses we are just window dressing. Sadly, many of our excellent and numerous Spanish nurses have left, because they only accrue seniority pay on their return to the Spanish system if they are working in an EU country. Our loss, Germany's gain apparently.
|Thread: Outside jaws for Pratt 160mm 3 jaw chuck|
Try Home and Workshop, I think they keep quite a few used sets.
|Thread: Hi from Sheffield|
Hello and welcome,
Not long retired and moved from Crookes to Buxton, in search of more affordable space and a decent workshop/garage.
Also a selection of bikes and a marlin kit car, though not self built.
I guess you already know good places to obtain materials over there, but ask away if I can be of (minor) assistance.
Edited By peak4 on 17/03/2020 14:09:38
|Thread: This is me...|
Hello, recently ex Sheffield and now retired to Buxton.
Posted by Nigel Bennett on 16/03/2020 13:56:03
Similar to Bill, I've used Unimat chucks in both Myford & Boxford lathes; I turned up a flanged mild steel spigot with M14 x 1 thread on it and the setup is excellent for gripping little fiddly things that can't easily be held in bigger chucks.
Yes I did exactly that, on spec, at Doncaster show a couple of years ago, got it home then realised mine's a Simat, so 14x1.4mm
Yes, I've now made one that fits, the main advantage for me is that the jaws are smaller, so they fit and expand into smaller holes.
Posted by Neil Wyatt on 16/03/2020 16:33:34
Chloroquine does show promise; it was sold out about a week ago...
Unfortunately as an old generic drug mass producing it won't make anyone rich, but hopefully someone, somewhere is ramping up production just in case.
I spotted this article yesterday, so maybe someone is thinking ahead, but not announcing it widely to save panic buying depleting national stocks.
I assume, as a generic drug, it should be easy to ramp up production though.
The Australians are doing clinical trials, but not heard about any over here.
|Thread: Slip gauges - dealing with patches of rust|
Before going as far as an abrasive like Scotchbrite, the motorcyclist's trick for removing rusts spots from polished chrome, is to use crushed aluminium foil and Coke ( or a brand equivalent that still has a bit of phosphoric acid in it.)
I've soaked rusty stuff in normal vinegar, which seems to turn the rust black, and soften it; might take several hours, or even overnight, so it will be hard to monitor for possible damage.
I've personally not had it affect the parent metal.
One than then just brush it with a soft stainless brush under a hot tap, and immediately spray with a water repellent such as WD 40
The hot tap means it will self dry after a wipe with a towel, as re-rusting starts very quickly.
N.B. I've never tried either of the above with slip gauges.
Posted by David Noble on 15/03/2020 13:04:52
Don't bank on me having any more experience than you! I suppose they took around 3 weeks but only a few hours each day in the workshop.
If I can help, feel free to contact me. Just start at the beginning and concentrate on one part at a time.
Cheers David, not one I'll be starting in the immediate future, as I've got a little surface grinder to get working properly. In order to do that, I need to make a bevel straightedge; in order to do that I'm on with making a couple of scrapers etc.
I'm sure you know how it goes.
I picked up one of the Hemmingway kits from John Moore (Bogstandard) in his workshop clearance.
Whilst I accept we have different machinery and you probably have more experience than me, how long do you reckon it took you to build it. (yes, I know it's not a race)
Also, any useful tips?
I also thank Raphael for an informed and non sensationalist opinion.
It's something of a shame that it has to come via a minority forum, rather than the mainstream media.
Keep up the good work, both on here and in your professional life.
(p.s. my previous post should of course have read as "I'll stand to be corrected, but I think we have a little over 4 high dependency beds + 2 ICU beds per 1000 capita.)
|Thread: Finally got the milling machine home.|
Posted by old mart on 14/03/2020 20:44:06
I notice that you have a Clarkson Autolock for the mill. ...........
Edited By old mart on 14/03/2020 20:53:16
It looks to me like Steve has a Clarkson S type chuck.
My MT2 one doesn't have the extra left hand threaded collar.
Also it's not suitable for plain shanked cutters, requiring threaded ones of the Clarkson style.
The C type (still a Clarkson Autolock) has a separate collar into which the collet fits, and also has the left hand nut at the top.
Mine works fine with plain shanked cutters, as the extra internal collar closes the tines of the collet.
On the S type, the cutter's shank needs to project backwards through the threaded portion and engage on the pointed centre to shove the collet forwards far enough for the nut to close it.
The C type has two little pegs on the back of each collet to drive it, whereas Steve's S type has two flats.
The similar Titanic, has a half cutout on the rear to provide the drive, but again, can't cope with plain cutters.
Fortunately, it looks like Steve also has some ER collets so he can use plain cutters OK; all carbide cutters I've seen have had plain shanks.
|Thread: £15,000 for a Bridgeport!|
It looks like many/most of his model machines are in the auction, but mainly with reserves of £2-3000.
Whilst the Bridgeport is more complex, I wonder if there is a typo, of the auctioneers already have had contact with some interested parties.
I've even done that on the Myford, using a Simat chuck, but I did at least use all the jaws on the big one.
Posted by Martin of Wick on 14/03/2020 20:43:26
Posted by Plasma on 14/03/2020 19:09:45
Am I missing something?
If normal seasonal flu kills 8000 people in the uk and this covid is not much worse why are we taking such huge measures to control it?
because it is 10 times more potent than the average flu and very serious for 15% of cases
Edited By Martin of Wick on 14/03/2020 20:44:35
Do a few quick back of the envelope calculations;
Currently UK gov are suggesting "Herd Immunity" if 60% of the population get infected, though that's a figure widely disputed by a number of other experts, who suggest a minimum of 70-80% and some say even higher.
Obviously there's no way of knowing currently if that percentage of the population are likely to get infected, so I'm not trying to be over-dramatic here, and just providing a possible illustration, which I seriously hope is wrong, but why even publicise this number as part of the strategy unless it has relavence?
Taking best case scenario on the 60% estimate/requirement with a UK population of 66 million approx.
60% of 66 million comes out at 39,600,000 infections.
Death rate is estimated at 1-2%, so again, taking best case, that leaves 396,000 predicted deaths, in order to achieve "Herd Immunity".
It sounds like a potentially dangerous strategy if it all goes per shaped.
From Italy, it seems that, of the small percentage who do require Critical Care & ICU intervention, of those who are on ventilators and receiving full support, there is about a 40% death rate for over 60s ( I assume that is all over 60s, so includes 70s, 80s etc)
Italy has about twice as many high dependency/ICU beds as us, and I think ours are already 80% occupied.
I'll stand to be corrected, but I think we have a little over 4 high dependency beds + 2 ICU beds per capita.
Italy has sent some military personnel into medical ventilator factories, to assist boosting production, and China has sent a large aircraft full of medics an 1000 extra ventilators to Italy, along with other medical supplies.
Some estimates suggest we are a couple of weeks behind Italy, as regards infection rates, though clearly I don't know the accuracy of that.
Here even hand sanitiser is virtually unavailable, Gov is woeful, and folks are stockpiling toilet rolls.
Without straying into politics on an engineering forum, we have no idea how many of the population are currently infected, as the advice at the moment is;
"You do not need to contact 111 to tell them you're staying at home.
Testing for coronavirus is not needed if you're staying at home"
So essentially, no-one knows who's staying at home, and of those who are, no-one knows how many are infected.
I'd best leave it there before I get grumpy and stray into politics
Edited By peak4 on 14/03/2020 21:30:45
|Thread: Finally got the milling machine home.|
Posted by KWIL on 13/03/2020 11:33:11
Bill make a "spacer" to sit on the table, of such a height that you can use the table to lift the head into the correct position?
Cheers, that's what I did in the end, with a large block of wood. I probably should fabricate a clamp to make it all a bit safer.
|Thread: A free ride to hospital|
Folks, don't forget, that when some folks talk about "grinding" aluminium or steel, not everyone is thinking of a bench grinder with a wheel.
Knife makers for instance often use a 2"x72" (or 48" belt "grinder"
Other engineers may consider this as a linisher or belt sander.
When I was writing articles some years ago for a specialist motorsport safety newsletter, I did mention a particular accident where someone using a linisher had ended up with burnt fingers due to some sort of exothermic reaction when he's swapped from "grinding" aluminium to steel without cleaning the machine first.
I vaguely remember reading about it originally in the model engineering press, but this is some 20+ years ago.
|Thread: Finally got the milling machine home.|
Posted by not done it yet on 13/03/2020 10:36:33
Good British Engineering. Tom Senior was on my original list, but I really wanted both a vertical and horizontal mills. The Centec fitted that bill, in one machine, perfectly for me.
Have you come up with a way to lift the vertical head into place without getting a hernia.
I used the horizontal arbour for a job last week for the first time in a couple of years; I then promptly realised how much my current viral infection has sapped my strength, as it was all I could manage to put the head back in place.
I'm not really in a position to make a movable crane due to the workshop layout, though I might be able to come up with something attached to the trolley on which the mill resides.
Best solution would be a long riser block, but no longer available from any of the previous sources, so I may have to come up with a way to machine one on the Centec itself.
My Centec has a captive drawbar; I don't know about your new toy.
If it is similar, then the bottom end of the drawbar will preclude the use of a plain shanked drill chuck arbor.
I just set up in the lathe and drilled the ends of my arbors and tapped 3/8" BSW. (Your's of course my be a different thread.)