Here is a list of all the postings Nigel McBurney 1 has made in our forums. Click on a thread name to jump to the thread.
|Thread: Endmill smear of metal|
why spend cash on new end mills and carbide bits,when a simple home made flycutter with a hss toolbit or broken centre drill ground up to shape costs next to nothing and will produce a better finish as the tool tip rad,cutting clearances,rake etc can be chosen to suit the job by using a bench grinder.The burr is manly caused by blunt tooling.
|Thread: Boxford max useable Chuck size|
I have a 5 inch Burnerd 3 jaw for occasional use on my myford,and I have a european Bison brand 6 inch 3 jaw chuck on my Colchester,this chuck is heavy far too heavy for a Boxford,. I last worked seriously on a Boxford many years ago. Now although I can see no problem with occasional use with the Myford,I would not like to run a six inch chuck on the Boxford especially as you only have one set of jaws for your current 3 jaw and you will be tempted to use a larger chuck all of the time,I would get a good 5 inch chuck,with both sets of jaws and if that runs out of capacity then use the four jaw.
|Thread: Identifying brass?|
An friend who worked for a company that did a lot of work machining bronze and got me a lot of off cuts,once told me that one way of identifying bronze/brass was that brass can be annealed ,bronze cannot be annealed, I did try annealing a piece of bronze and it would not anneal like brass or copper does,though I do not know if this applies to all type of bronze. Aluminium bronze is slightly magnetic,our local scrap merchant keeps a magnet handy for testing.
|Thread: Bandsaw overhang|
Garys holding method goes way back,the Rapidor power hacksaw in the factory where I first worked, had an accessory for holding short lengths of material ,it consisted of two malleable iron cast plates each one having two V s of differing size, plus a long threaded bolt, the two vees allowed various diameters of short stock to be held securely without tilting ,plus short lengths of flat stock could also be held,the bolt took up the gap at the other end.The Rapidor came new to the factoy so the accessories were looked after,I have seen many of these saws in dealers and at auctions ,none had the special grippers for short material.I made some of these plates for my saw using 4 x 1/2 in flat bar with angle iron welded to them to form the vees. I have often thought of making a similar vee jawed gripper for my DO ALL band saw but like a lot of things it does not get done until there is an urgent need.
|Thread: Undoing a castellated nut!|
a simple pin spanner will work in round holes as well a square cut outs,the advantage of square cut outs is the pins do not have to be very accurate regarding pitch. For the butcherand bodgers a square cut out is a lot easier to hit with a punch than trying to punch a round hole.
|Thread: Ball Races and 'Brinelling' (whatever that is).|
Hard drive bearings,disc spindle and actuator arm, in my day spindle bearing ball races had more than standard clearance and had preload via a spring,the lubricant and the quantity was to a special spec as a min 5 yr life was specified,I would not bother to re use these bearings in another application. I have seen severe brinelling on motor cycle head races particularly on competition bikes, I had a new Greeves trials bike back in 1961,which one of the first bikes to have timpken taper roller, after a couple of years use I removed the forks to check the bearing condition and lubrication as there was no greasing nipple,the bearing outer race surface had bright spaces,separated by black line of corrosion as the steering lock limits the travel of the rollers,very slight wear could be detected on the bright areas,in those days Timkens were expensive,so the old bearing continued in use and still being an apprentice with limited funds,replacement of chains and wheel bearings was deemed more important,after the overhaul when riding the bike on the road there was a very slight shimmy felt through the handlebars. Back then a lot of trials competitors rode their bike in competions at the weekend and it used it for road use during the week, summer holidays would be spent giving the bike an annual overhaul,,One thing I read about recently was that some road racers still prefer the cycle cup and ball bearing assembly compared to taper bearings as they reckon the bikes steer better.
|Thread: source of bronze|
I wonder how our ancestors got on in the broze age,they had no books or forums,but they found out how to mix and melt tin and copper.
|Thread: lathe knurling tool|
The way I was taught was to set the knurl at the depth required and feed the tool from left to right,flooded with soluble oil to wash swarf away. To finish a knurl a 45 degree chamfer was turned at each end of the knurl with a form tool. ref the end feed knurl I have used a similar type of knurl that one had two opposed jaws which could be adjusted in or out to suit the work dia and each one could be rotated to adjust the knurl pattern from parallel to 45 degrees, work well on most non ferrous and mild steel once set it did not need adjustment ,used on Ward 2A capstan lathe and end fed via the turret ,those knurls did thousands of parts ,mainly microscope fittings.
|Thread: Piston Ring Grooves and Rings|
I have restored a lot of stationary engines, from 1.5 to 5 inch bores,the earler engines 1895 to 1930 tend to have very wide rings a few 4 stroke were pegged .when I started 50 yrs ago no spares were available so it was relatively common to find engines which had a number of narrow car type rings fitted into the wide grooves on the older engines,so for a time i followed suit and fitted a stack of rings in the groove nearest the piston ,the remaining old rings were left in place,as I felt that too many modern rings would cause too much friction. This practice worked and improved compression in worn bores,after all the Clupet ring is like two rings joined together in a spiral and they work .Then for a long period we restorers found a company that made rings in small batches similar to the old style rings,they closed and since then I have made some rings from spun cast iron,on the last engine which had a worn bore I made two narrow rings to fit in one groove ,as I thought a narrower ring would flex a bit more and help with the sealing ,the next groovee had a full width ring and the last groove had one original ring, why leave an original ring,well a Hornsby instruction booklet stated when replacing piston rings always leave one original ring in place so thats what I did,so now I have a magnificent 1910 4hp Hornsby petrol o/c engine which runs very well.
|Thread: Help needed, can't release cast iron wheel|
I have restored and worked on many stationary engines ,with flywheels from a foot to 4 1/2 ft in dia,the most difficult are those with well rusted jib head keys,the key causes more problems than the flywheel.I had a customer bring me a 5hp lister CS diesel with spoked fly wheels 30 inches dia.keys came out ok but the flywheels were a tight fit on the shaft .I use the 15 ton ram removed from my press and with a mome made puller,a split steel disc behind the hub,pumped up ram to 15 tons and nothing ,then my wife came to see how I was getting on,she suggested giving the ram a few more pumps until the gauge was into to the red,then at nearly 20 tons there was an almighty bang and the wheel came free. I suspect that there may have been a problem with the flywheels coming loose in service and thewheel was made a tight fit as I had seen one of these engines shake a key loose when running.As it alwys happens a visitor came round and saw the Lister with it flywheel nearl removed, he had served his time at Listers and he told me that one way of shocking a flywheel free was to get a hydraulic puller really tight then hit the flywheel hub with a really big hammer with blows 90 degrees to the crankshaft axis. He agreed with me that hydraulic pullers should not be hit with a hammer only hit screw type pullers, plus I do not believe in heating spoked flywheel hubs,any expansion on the hub puts an outward force on the spokes and so puts a stress on the rim.Taper fits can get really tight ,an easy check to see if the fit is tapered is measure the shaft diameter at each end of the hub,then get an oversized mechanical puller which does not deform or bend and really hit the end of the puller,taper fits really do need a violent shock.
|Thread: Junior hacksaw blades|
my first genuine eclipse junior hack saw frame ,new in 1958 and still has my clock number stamped on it,seems to have more spring in it than later ones from unknown sources,and holds the blade tight,still works ok ,I have always cut in the push direction,never tried to pull.The quickest way to ruin a blade is to cut "unbrako" socket screws. In more recent times i tend to cut toughened bolts and socket screws with a 1 mm disc in an angle grinder,then this yearI purchased a Dewalt cordless angle grinder and that tool is useful saves the need for long cables when using it around the sheds and yard.
|Thread: Dividing head for lathe - Myford vs BS0/1?|
Apart from high speed cutting of clock wheels,I never did see any point in using a lathe spindle as the dividing element and cutting with another attachment, A lathe spindle is designed to be used for driving work and cutters so why waste the spindle,far better to have a separate index device,I have a Myford dividing head,and found it useful,the only snag as I see it is that the main workholding device is the chuck which being threaded could under intermittent cuts become loose. though this can be overcome by using the 2MT spindle socket,and make up a mandrel to suit the socket and secure the gear to be cut,support the outer end of the mandrel with the centre. There are a lot of illustrations in tearly technical books of workpieces secured via the M/Taper. the mandrel should be secured in the taper by a stud and nut, and idealy the gear held firm by a nut and a keyway in the gear locating in a key way in the mandrel. The book "a practical treatice on milling "by Brown and Sharpe who were one of the most famous machine tool makers in years gone by is a good read I got mine via ABE books for a few pounds those published in the 1930s are very good though it shows industrial use not model work,though there is a good chapter on gear cutting.
My Colchester Triumph came with both bronze and roller fingers, though I never used the rollers. Industrially all i ever saw was lubrication by lots of oil from the oil can or flood lurication of soluble oil. In order to concentrate on the turning rather than continuously using the oil can, I used a drip feed stationary engine oiler mounted on a bracket and attached to the fixed steady,this kept a regular flow of oil. When working on stationary engine crankshafts which usually have a keyway at each end to drive flywheels or pulleys,I would make up a bush which was a good fit on the shaft and secured by a grubscrew which located in the keyway,this gave a continuous bearing surface for the steady fingers and spanned the keyway.Though I have never had any problems with steadies marking the work,we were told it was more important to make sure the steady was dead in line with the centreline of the lathe,as an out of centre steady will cause the workpiece to "walk" out of the chuck jaws.when using a steady keep an eye on the temperature of the work,if it gets too warm it will expand and put pressure on the steady bearing pads and this expansion can mark the work,
|Thread: Crowning a pulley for a flat belt Question|
General practice with belt drives ,in our sphere of vintage steam and oil engine belt drives ,was if the motive power runs at a higher speed than driven machine ,the large pulley on the machine would be crowned and the small pulley on the engine would be parallel, where it was the other way round ie a traction engine driving a faster rotating small pulley on sat a threshing machine then the T/E flywheel would be crowned and the small pulley would be parallel and very often with raised sides to stop the belt slpping off as the threshing machine was never in perfect alignment as it was on rough ground, Now on oil engines as they very often ran faster than the driven machine the engine belt pulley was parallel and I have not come across any genuine manufacturers pulley that was crowned,with the exception where they had to drive a generator or thrashing machine and these would be vey large pulleys. Where it was common in steam practice for portable and traction engine to have crowned flywheels ,oil engines tended to have flat face flywheels only one of my oil/lgas engines has a crowned flywheel, So for a small pulley is crowning essential,?
|Thread: Machining phosphor bronzes|
There is a comment in the initial post that phos bronze is good for bearings,phos bronze is not a god bearing material,the only time phos bronze can be used a bearing for shafts,is when the shaft is very hard and ground and there is a lot of lubricant,leaded bronze is a far superior bearing material. One use is where steel or iron pivoting levers with limited motion are bushed with phos bronze to make the motion easier and to prevent seizure from corrosion in exposed situations,
|Thread: RCD Tripping|
If your S7 motor has ventilation slots to help motor cooling,a known problem is swarf falling or thrown into the slots a,resulting in various electrical faults including power tripping and motor shorts leading to motor burn out, this can cured by fitting an aluminium or steel shield over the motor ,allow some space for airflow and do not foget a shield will cover motor bearing lubrication points if fitted. Another fault,which arised in my workshop is long damp periods due to the rain, insects can get into swichgear,or 13 amp skts, spiders are worst with their webs,the insect or the web gets damp and thrws the trips. My solution a long time ago was to seal all the cable entries and any unused mounting holes with mastic,no more problems until a month ago,lighting circuits were ok it was just the ring main around the shed,9 sockets to check,so it was a case of checking each socket in turn it was the 8th one that had the spiders web.All cleaned now and tripping stopped, it was so long ago that I sealed the sockets that the mastic had hardened a shrunk and let insects in,another job to do. Then I had a thought ,last year we put the freezer in the garage and that has its own ring main with trips,so those sockets need checking I have also placed a red neon warning light visible through the garage window so that I can check the electrics are on,Could cause a lot of domestic upset if the freezer circuit tripped and was not noticed.
|Thread: Cutting Oil Fumes|
Why use cutting oil,lot less problems with soluble oil, years ago there were where i once worked over a hundred auto lathes going llke mad all day,there was no real objectional smell or much in the way of fumes,as the lubrication was cutting oil and lots of it in full flood and did not get hot ,plus very little if any carbide in those days.Its not a good idea to use cutting oil in small quantities on red hot chips.
|Thread: Stuart D10 Metric Plans|
When I started, dwgs used fractions and decimals, the fractions indicated that the dimension could be made to a wider tolerance,the decimal dimensions indicated that lot closer tolerance was required, it was quite common for many companies not to have dwg tolerances in a indicated box at the bottom of the dwg,sometimes tight tolerances would be specified against individual dimensions.In earlier times dwgs would have notes "make to shop practice" or " "Bore to suit" ,"drill and ream "to a fraction dimension just indicated to the skilled man that a nice round ,smooth hole was required no tolerance given. These practices were ok when long established UK companies made everything in house, When companies started to use subcontract suppliers,or make items for or assemblies for say a government contract ,start to mass produce products where spares were required regularly then dwgs had to be specific regards tolerancing ,finish,material etc. Where I was first employed we were expected to turn the brass fittings of a microscope using fractional dims to within plus minus .005 of an inch or better using a steel rule.Diameters which were theaded were measured with a micrometer,When I went to my second job they used imperial decimal dwgs with tolerances specified and that did take some getting used to dont know why but I found that working to decimal imp and using a rule with tenth and 1/20 ths of an inch was awkward and slower.At a third company ,a USA based multinational ,they used decimal /imperial ,here I was an engineer involved in procuring subcontracted parts so never got really involved actually making parts,so did not find any problems,Metrication came along and again no real problem,as most of the scientific instruction at grammar school was in metric units,the science masters scornful comment one day on imperial units was "only engineers and plumbers use imperial units" In 30 years of retirement ,topping up the pension I took on any work both to imperial or metric units,despite having a fully metric lathe and another lathe with dual dials plus imp and metric mills I found that I was far quicker using imperial dimensions because my initial training was in imperial units and spent my first 6 years using them,and I just cannot see any need to convert a dwg from fractions to decimal, the conversion factor is just in my memory if I see say 3/16 ins I just know that its .1875 ins.
|Thread: Replacement lathe lamp suggestions?|
Long LED conventional double strip light screwed to shed ceiling,I have the original makers lo volt lamp on my Colchester ,I never use it .
|Thread: Magnetic v-blocks - how useful these are?|
I have had a Mitutoyo magnetic vee block for 30 years,I rarely use it,the snag I found was that if you want to drill a cross hole in a shaft on a drilling machine,a centre pop on the shaft is set central by eye,then the mag "on" lever is operated,thats ok it holds the work resonably securely but the magnetism in the base stops the block being slid around on the drill table to get the centre pop under the drill point,I prefer an ordinary vee block,if precision is required then its either use a vee centre in the lathe tailstock or on larger round bar work its a machine vice on the vert mill set up central using a wobler tool.I have three sets of paired vee blocks ,plus a very precise Bilton single block and an Eclipse toolmakers vee vise. Though they all suffer with the snag of the drill chuck can hit the clamp on occasions. I do have a pair of old Verdict v blocks which have the an arrangement of slots on the sides of the block which contain the clamp so if the block is laid on its side the clamps do not foul the surface plate or drill table,My mag vee block came "free" I would certainly not buy one.My pair of Eclipse hardened steel vee blocks,are now 60 years old very expensive in those days bought at a small discount via the company apprentice tool scheme,though still in excellent condition.
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