Here is a list of all the postings Nigel B has made in our forums. Click on a thread name to jump to the thread.
|Thread: Does this count as a manual tool?|
You wouldn't want to startle the operator and have him turn quickly..
This is, apparently, why you don't see hand-held waterjet cutters any more
(not that I ever saw one in the first place !).
|Thread: 4 Jaw Chuck clean it or not?|
You have no need to remove it from the back plate. Doing so will not show any innards of the chuck and there will be nothing to clean or lubricate
By the look of it, you may need to remove the backplate to remove the jaw screw retainers ?
Can't see for certain from the photos, but many 4 jaw chucks have the jaw screws retained axially by a thrust "plug" that engages with a groove in the screw. These plugs are inserted from the rear of the chuck body & removal (to allow removal of the screws) will require the removal of the backplate.
But it's nothing to get worked up about - it was made as individual parts, should dismantle back to those same individual parts for cleaning up & then re-assemble again.
|Thread: Squeaky 7x12 bearings|
Roiller bearings need very little preload.
Depends on the application. Timken used to (maybe still do ?) make a taper roller bearing called a Hydra-rib that allowed the preload to be changed "on the fly" using hydraulic pressure. De Vleig borers used them - in low range (where heavy loads could be expected) the pressure was increased to run a higher preload. In high range a lower pressure was used so bearing heating was reduced at higher speeds & higher stiffness was not required.
You should only fill the bearings about 40% with grease.
Doesn't matter as much with taper rollers. Unlike ball bearings, which "churn" excess grease within the bearing causing overheating, taper rollers "pump" from one side to the other so the grease gets expelled in normal operation. More of an issue with taper rollers is keeping them greased - hence the usual provison of some form of re-greasing arrangement on TR applications where many BB applications are greased-for-life.
I would expect over tight bearings to start to get warm quite quickly, getting uncomfortably hot at higher speeds after longer running. Some MTBs use the headstock temperature after running at a particular speed for a particular time as the method of setting optimum pre-load - too cool, increase - too warm, decrease.
|Thread: Motorcycle General Discussion|
Nice job there TG.
My brother-in-law had a late model "pink" TY250 when they were current.
I started with a twin-shock SWM (280 Rotax), then a monoshock Armstrong (280 Rotax), followed by a JCM 240 Europa & finally a twin-shock Honda TLR 250. My wife had a Fantic 300 twin-shock & a Beta 240 mono. Trials used to be very popular in Yorkshire, but I don't think it is as much these days - finding suitable land & getting permission to use it was always a problem, which has only got worse.
After 5 years or so competing at club level, I gave up trials when the Honda was stolen some 20 years ago.
|Thread: "Vintage" CNC|
Anyone remember plugboard capstan lathes. They always looked like black magic to me
Oh yes - very profitable for me as an apprentice was a Hepworth plugboard capstan lathe. This used a Herbert (No. 4 Pre-optive IIRC) as it's base with a Hepworth plugboard control. The control had a couple of dozen TTL logic circuit boards, which were frequently "iffy" - many boring hours sat waiting for an intermittent fault to appear to use signal injectors, heat gun, freezing sprays etc. to try & identify where the problem was. Usually though (& this was the profitable bit for me) I had to take the suspect board to Hepworth's works outside Holmfirth (our works was in Brighouse) to have it run through the test rigs there. I ran a sub-250cc motorcycle & got the small car mileage rate, so a nice run out in the middle of the day paid for my fuel for the week.
In the late '80s I comissioned & trained on a couple of new CNC VMCs installed in Czechoslokvakia (pre the end of Communism). One of the milling machines there used 35mm movie film as the "tape" - a very basic control moved the axes in sequence to limit switches, the relevant switches being punched onto the "tape", which was then spliced to be an endless loop. The programmers I was working with brought out the reel of film that they had been given to use and, holding it up to the light to see a few frames, it was obviously an old propoganda film, with an actor made up as Lenin on a podium giving an animated speech.
but they were a plumbers nightmare, blowing seals and leaking and then the concensus was to concentrate on servo and stepper controls
And hot and noisey, as well as taking up a large amount of room for the oil tanks, coolers etc. And very, very finicky about cleanliness - machines were shipped with "flushing blocks", which were used to replace the servo valves to allow the system to be flushed for several hours if the hydaulics had to be worked on.
But before reliable, high power electronic switching devices, there was little option if you wanted a high torque servo drive. Mostly hydraulic motors driving ballscrews, but some (certainly some Newall borers, probably others) used hydraulic cylinders. Taken plenty off & replaced them with modern electric servo drives (and managed to interface a modern control to the old servo valves on a Newall cylinder driven jig borer) in my last job.
Mylar tapes were only used for the Diagnostic and Parameter tapes on the machines I was set on to learn the maintenance of in 1977 - much too expensive to use for day-to-day operation. BTW, if you come across any unused rolls of 1" tape, don't bin it - it hasn't been made for ages & there are still a few die-hard users who will pay whatever you want to ask to get hold of it !
Through holes to bolt it to the desk to stop it growing legs ?
|Thread: How do I adjust the quill?|
Is it this one ?
This came from the link on this page : **LINK**
|Thread: Bridgeport EZtrack|
as the feed screws will need changing to standard acme.
Ballscrews are quite useable manually with handwheels - some ballscrew companies (Hiwin for one) did conversion kits to bolt-on to manual Bridgeports to replace the acmes.
|Thread: DIY hearth|
My employer is currently making wood fired pizza ovens using a perlite or vermiculite & Portland cement mix. The cured shells have proven to be quite weak, prone to cracking & appear to be hygroscopic - the initial experimental attempts that didn't crack during production have failed after a few firing cycles, possibly due to getting damp during periods of non-use & then heating up too quickly when next used. IIRC he did try adding ground-up oil-absorbent clay granules as a binder at one point, but I think the recent builds have been without. The shell wall for these items is around 40 -50 mm thick. I think he is on Mark 5 or 6 at the moment - the latest "mod" being to tile & grout the outer surface to try & improve rain resistance (earlier versions had several coats of masonary paint). The earlier variations were experiments with the mix to get better consistency after failures either during manufacture or after a few uses. He is using a Belle cement mixer to mix the stuff & allows it several days to dry out before removing the forms & an intial gentle firing.
Don't know if that will help or not - but may point towards having to experiment with mixes etc. to get an acceptable result.
'2 keys', why 2 keys?
Easier / quicker to set with a key in each of the opposing jaws - you can only push with a jaw, so using one key means having to spin the chuck 180 degrees to get to the other side if that is where the push is required. Using 2 keys allows you to push from either side as required without having to rotate the chuck.
Nigel B (another who was taught to use a 4 jaw independant in an apprentice training school)
|Thread: The diesel controversy|
They can and do, but they aren't supposed to.
HMG say otherwise - look at the column "Goods vehicles (not more than 7.5 tonnes maximum laden weight)" which shows motorway speed limt as 70 mph. This is the same as "Cars, motorcycles, car-derived vans and dual-purpose vehicles", "Motorhomes or motor caravans (not more than 3.05 tonnes maximum unladen weight)" , "Motorhomes or motor caravans (more than 3.05 tonnes maximum unladen weight)" and "Buses, coaches and minibuses (not more than 12 metres overall length)" - all are 70 mph on motorways.
Dual carriage ways & single carriage ways are another matter, but for motorhomes "not more than 3.05 tonnes maximum unladen weight" sets the limits, not maximum permitted weight.
Once done you can drive at 70mph on the motorway, instead of 60.
Vans can drive at 70 mph on motorways anyway, so no change there ?
|Thread: Engineers blue alternatives|
Or Cromwell Industrial Supplies if there is one near you
|Thread: Truing up chucks|
Of course there must be many exceptions, but to me the need for a fitter either indicates small-run production or a firm vulnerable to competition.
I would put many machine tool builders in the "small run" category. Machine tools are not consumer durables like printers in terms of volumes produced & the market is too small to justify the substantial investment required to produce say, a mini lathe or mill in a robotised factory. If Joe Public bought a new mini lathe at Currys every couple of years like they do printers, things may be different !
My former employer was of the opinion that fitters should be unnecessary if the machine shop did their job properly - but also complained about the cost of having parts precision machined. I understand that some volume builders ( Haas springs to mind) do machine to tolerances that require the machines to be "assembled" to the required accuracies from a kit or parts, rather than being "fitted". They do this by using linear guides that bolt-on, rather than require precision fitting like plain bearing machines - which is fine if a linear guide machine does what you want. If it doesn't, then it's back to a "hand fitted" plain bearing machine. They have also invested very heavily in the plant to produce the parts to the required standards.
Michael, fabrications where you suggest would probably cost more than a casting. The 7 series lathes were designed to be mass produced & (initially) sold at a competitive price. I guess that as their volumes declined, they started to believe the hype about the "higher quality than an import" & adjusted the pricing accordingly, rather than investing in more modern methods to produce the same (or better) quality product cheaper. An affordable British lathe - rough edges or not - is not likely anytime soon, I think. Though if you know why it isn't rocket science to do so, please demonstrate how !
I presume what lathe manufacturers did (or maybe still do) was to temporarily fix the tailstock and head stock body together and bore/ machine all the mating surfaces at the same time. so that everything lines up on the bed.
You presume incorrectly, Michael.
Parts are made indvidually to tolerances & then "adjusted" on assembly to the required accuracy - that is what machine tool fitters are for !
|Thread: Aircraft General Discussion|
3/4 scale ?
1:1 scale - the real thing.
|Thread: Doncaster show|
I Agree regarding comments about Doncaster being better than Harrogate.
Maybe better than Harrogate as you remember it from the last ME Show, but not now after it has been redeveloped. I was there last weekend for the Northern Shooting Show & can see why the cost of hiring the venue has increased - the replacement for the rather dingy hall that used to house the model boat pond & most club stands is bright, airy & about 4 times the size it used to be. And there is another cafe at the far end of the new hall as well as the "between the halls" original, as well as extensive outdoor catering on a piazza that I don't recall being there before. Still no easier to get in though - 2 mile que at 8.15 for a show that opened the doors at 8.30.
After seeing the exhibitor list for Doncaster, I chose the NSS instead this year - maybe reconsider next year, depending on who (trade-wise) can be enticed to attend.
|Thread: The diesel controversy|
the emission test passed no problems
The MoT test for diesels is a visible smoke test, not "emissions" such as Nitrogen Dioxide. I am pretty sure I have seen something about proper emissions tests being developed for MoTs, as the current test is acknowledged as being inadequate. As well as being illegal, tampering with emissions control equipment is downright antisocial IMO.
The "problem" of older diesels will work it's way out in reasonably short order due to attrition. Euro 4 limits came in in Jan 2005 & Euro 5 in Sept 2009 - I pass a vehicle breakers on my way home & most cars there are post 2000 (many post 2004), so it won't be long before many of the Euro 4 cars are getting recycled naturally. The costs of basic repairs are such that even a relatively minor failure in a 10+ year old car makes it unviable to repair - even if you can get the parts. I have shifted 2 out of my last 3 cars because of actual or potential repair costs, the last being a 5 1/2 year old Toyota Avensis with 85000 showing that was eating money. It had 1 front wheel bearing under the 5 year warranty (just within & done with bad grace), another front bearing failed 3 months later & Toyota wanted £500 to replace it (Independant did it for £275). A rear bearing was noisy 2 months later + the CVT gearbox ws getting noisy & Toyota didn't supply parts, only a brand new gearbox for £4500 ! I got £4500 in P/X for another car instead - pointless pumping money into an older car.
The bigger problem with older diesels would appear to be busses, taxis & large commercial vehicles, which have a much longer operating life than cars and light commercials. Legislation to mandate retrofitting of emission control equipment or re-engining with compliant equipment of these vehicles would appear to me to be a more sensible option if faster air quality improvement results are required than car scrappage schemes would provide.
|Thread: warco lathes.|
Various Colchester Student 1800s, Chipmaster, Triumph 2000 + Harrison M300s at this auction, ending this week **LINK**
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