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: Making Parallels|
I was given a large piece of 1/8 thick gauge plate,thin parallels are useful when setting small thin pieces of work up in the vice,I still work imperial, so if you have say piece of 1/4 square material and want to remove say 1/32 then what is required is a narrow parallel but with height 3/16 below the top of the jaws,so I made a series or pairs of narrow parallels where the height below the jaws was more important than width this allows me when dealing with standard stock to be able to set up this material with a good grip on the work with enough protruding above the jaws to allow machining,very useful fo machining parallel keys and similar work, A toolmaker friend used to use aluminium bar for parallels to save damaging small cutters,he just fly cut them in pairs,just make sure the vertical head is trammed truly vertical. Hardened and ground Industrial parallels were used as they maintain accurracy over years of use and withstand lots of beating down of jobs onto the parallels with a lead hammer,nothing wrong in using soft parallels.
|Thread: Lollipop maybe?|
When I bought my 2 inch M & W micrometer via the apprentice tool club,the boss took me down to his office and got out a stack of 1 inch dia gauge blocks ,which were about a 1/4 inch thick,a said I give every,one who buys a 2 inch mike one of these gauges to check the mikes accuracy until I run out of them,they were made to slip gauge accuracy,he made a point of making me pick up the block by the flat faces,with the instruction " always hold them on the flat and never hold them on the gauge faces ,fingerprints corrode gauge faces" I have never forgotten that and have always kept the gauge lightly oiled and still the wooden M & W mike box ,the mike and gauge are still in use 60 years later.
I expect a similar circular gauge came with the height gauge.
|Thread: R8 or morse taper 3?|
Before dowsizing I had an large Elloitt turret mill with 30 int spindle,which was totally inadequate for a large mill,particularly when boring,and with the tooling I had the 3 mt drill holder had to to be removed from the spindle to release a drlll, My other horizontal mill will with 40 int spindle the morse taper holder did allow access to the drift slot while it was still in the spindle but projected a long way out of the spindle,also int 30 tooling is not readily available second hand. So for drilling I bought a 3mt Meddings, now I only have a smaller Elliott omnimill with vertical and horizontal spindles both 3 mt ,the 3 mt does have a big advantage to me,my colchester,the meddings and the omimill all have the same spindles and tail stock. I have never used a Bridgeport ,though I can see the advantage of the R8 taper allowing collets to be so close to the spindle bearings,to improve rigitity of cutters. On my mill I use er 32 and 40 holders ,the big advantage of the ER system is thet each collet will grip over a 1mm range,ideal when holding drills. I have not had an ER collet slip yet,though I prefer to use a Clarkson on really tough materials. I suppose the ER system came about when plain shank solid carbide cutters became availble and they could not be gripped in a Clakson collet. On the big mill I had the Bristol Ericson collets, I found that these would slip,the ER system is far superior.
|Thread: Drilling HSS|
I also convert HSS hacksaw blades for my Rapidor,Requiring 14 inch blades,I found at one time there were numbers of 17 inch blades on the second hand market as there few customer needing 17 inch blades,so deals could be done buying job lots,I shortened the blade then drilled the blade ,I used drills with brazed carbide tips from the chap who went around the steam fairs selling these drills ,his demo of perforating large old mt drills and old files was impressive,he was not amused when I asked why would you want a hole in a file,was it for hanging the file on a nail,he did not have a sense of humour.
|Thread: Hermes Parcels|
DPD recently just lost a parcel of bird seed,supplier just resent a new supply, Placed an order fromScrewfix,courier is Parcelforce,parcel returned to depot "unable to locate address " parcel still on system as "back at depot" Local post office told me that Parcelforce changed distribution depot for our area and their drivers are not familiar with our area,its a business and they should be trained,or perhaps they cannot read as there is a house name on either side of the drive. Its all blamed on virus 19 but they are still charging the same for a poor service , I think I shall give up on ordering from the internet for a while. The snag is that all these type of services have no means of direct communication,only help on the website or automatic phone systems .
|Thread: Tailstock die holder|
For concentricity drill and ream the hole for the tailstock bar at the same time as the bore for the die. When I made my first die holder for the Myford I just copied the commercially made holder that was on a Boxford at work,,steel body with knurling ,1/2 inch hole through the centre ,the support rod was held in the tailstock chuck ,and cross hole for a tommy bar , the knurling was so that small BA theads could be threaded by just gripping the holder in your hand,olt quicker than using a tommy bar. After over 50 years I have a number of holders to hold dies from 10 BA to 3/4 BSP some are made from steel the rest from aluminium alloy bar (HE 30 ) they have withstood hobby and 25 years commercial use. things I have learnt, three equi spaced tommy bar holes are easier and quicker to use on a larger lathe, one of my tailstock support bars has hole down the centre so that long small threads dont foul on the end of the bar. Long threads can also foul on the tommy bar ,so one of my tommy bars is made from larger dia material than the bar hole in the die holder, the end of this larger bar is reduce in dia for a short length so that the tommy bar only enters the bar for a short distance and does not foul the workpiece. the die holders being alloy are lighter so can have thicker wall around the die and the tommy bar does not slip out. Do NOT allow the tommy bar to rest on the lathe bed , if you require a torque stop to stop the holder rotaing ,allow the tommy bar to rest on a length of steek bar held in a tool holder, necessary when cutting lots of course threads.Why a/alloy ?they are lighter,a quantity of material was/is available and if you should accidentaly drop one on the lathe bed they do not any damage, heavier Work is done on my Colchester which having forward/reverse clutches makes threading easy and quick,and the quantity of holders allows the most used dies to remain set in their holders.
|Thread: Using large dies|
Why not go back to the earliest lathe practice,screwcut the thread to just a little oversize and finish the thread with a high speed steel machine chaser ,do not use the very early type hand chasers ,their use was mainly on brass. When using a chaser under power the chaser has to be withdrawn very quickly at the same time as the half nuts otherwise your thread will turn into a number of parallel rings .
|Thread: Myford S7 Cutting Barrel Shaped Cylinders|
I have looked at the posts on here a number of times, lots of ideas but unless the right equipment is available its very difficults to measure wear and defects,two things I noted,from the lathe owner comments ,the sadle felt wiper was missing and there were scoremarks on the uderside of the saddle, perhaps showing the previous owner/s was not very careful.now particularly on flat guideways on machines that have spent a lot time maching cast iron,fine cast iron particle seem to get everywhere,and cause scoremarks in the direction of travel of the slide, My first boss bought a Kendal and Ghent plano mill ,a prewar machine with a two metre plus working traverse of the table,and three milling heads,the two flat bed slideways were so grooved and scored they looked like a piece of wood that a cat had scratched every time he walked past it,The boss said that was what continual use on cast iron machining will do unless the slides were kept clean and lubricated, the table was shipped out to be ground but the bed slideways were dealtwith in house by scraping using a large surface plate as a reference surface from memory the the slideways were about 10 ft or more long, I am still in contact with the fellow apprentice who did all the scraping ,I think if I had been given the job I think me and the boss would have fallen out,I hate scraping and you have to be a good tradesman to achieve true surfaces. This small plano mill looked out of place in shop making scientific instruments but it was needed to mill 2 meter optical benches which were true to within about a thou over length and doing a mainly inhouse rebuild of a near scrap machine was very economical .So if the Myford bed is reground then I think the saddle should be given the same treatment at the same time ,no point fitted a worn saddle to recn bed. Another thought ,I had a look at my S7 tonight,a 1973 machine with wide bed to saddle arrangement, on mine there is still in position in the saddle casting the rib where the earlier machines ran against the inside of the front shear, there is about 60 thou clearance this surface looks to be machined, now if a piece of steel is made fit in this gap and the surface which runs against the rear shear has some clearance,so temporarily converting the saddle back to guide system on earlier lathes ,the saddle should be guided by a relatively unworn inside surface of the rear shear,in fact there is probably no wear for some distance from the chuck as the tailstock rarely gets used this close to the chuck,might be worth giving it a try.
|Thread: Advice on lathe Threading tools|
Jim The work is held in the chuck with the spindle locked or if no lock the lathe is left in back gear, the apron is moved by HAND using the saddle hand wheel,, Where I first worked any keyways in gears and pulleys were cut in a 8 inch Willson lathe and it can be hard work,on smaller lathes care should be taken to avoid strain on the saddle gearing, a lever type attachment is far kinder to the small lathe. When cutting the keyway feed is put on with the cross slide,after taking the cut,wind the cross slide forward so that the keyway tool does not rub on the return stroke, on a big lathe with rigid tooling if you do not withdraw the tool on the return stroke it will take the edge off the tool right across. I was warned about this when I cut my first keyway ,after cutting a couple of keyways I forgot to withdraw the tool and took the front edge clean off,the work is not damaged but the tool needs a regrind. Hence the reason for clapper box toolholders on planers and shapers,but I was given an American book machine shop practice,in later years written by someone who knew his trade, he recomended when cutting internal keyways on a shaper to lock the clapper box tight to avoid tool chatter. Now this goes against what I was taught when cutting keys on the lathe,but when I aquired a 14 inch shaper I had trouble with cutter chatter and it worked and I did not damage the cutting edge of the tool,now both machines were not toys but I cannot see any reason why the tool edge breaks when using the lathe but is ok with the shaper box locked up,
|Thread: garden tractor wheel lug nuts and studs|
I have seen similar hub problems on 1950s steel "British Hubs" fitted to the back wheels of Dot and Greeves competition machines,where the sprocket bolts were forever coming loose.The previous owner no doubt had found that instead of the wheel nuts coming loose ,the action of the wheels over rough ground rattled the short end of the studs out of the hubs,the wheel nuts did not come loose .to cure the problem he reversed the studs and put a lock nut on the back of the hub, My solution would be to remove the hubs and drill and tap 3 new holes eqispaced between the old ones,as the back of the hub is possibly as cast ,a spotface should also machined around the hole, find some longer studs so that they can be screwed into the new holes and a nut to lock the stud fitted at the back of the hub,the spot face is essential to give a flat seating for the nut,its preferable that the nut is a Nyloc type nut, By drilling new holes you get a good thread,and you have a wider choice when looking for studs as they can be any thread and the holes tapped to suit, it does not matter if the thread is finer than unc, metric or BSF would be ok. Its just that the stud must remain really secure in the hub. I cured my Greeves hub by machining some 5/8 dia steel 1/2 inch long,brazing them in line with the worn threaded bolt holes in the flange then brazed them onto the inside of the spoke flange, It was quite difficult keeping the oxy torch away from the spokes i then used the sprocket as jig to drill through the brazed on bushes,then tapped the bushes and then had a long thread to secure the sprocket bolts, In more recent times I restored both a DOT and a Greeves trials bike though this time it was easier as I did it with bare hubs before I respoked the wheels. Happy days.
|Thread: How easy is it to make a chain sprocket?|
Try Tracy Tools,they stock gear cutters and they may have aquired some sprocket cutters,I have a sprocket cutter for 1/2 inch pitch I found that in a job lot of gear cutters I bought at auction. sprockets are quite thin so may vibrate during cutting,suggest make the blank thicker ,cut the teeth and then face to required thickness,
|Thread: Wyvern engine help!|
I have a ollection of engines,gas with hot tube ignition,gas or petrol with low tension ignition, petrol engines with HT magneto ignition, petrol engines with low tension ignition. they range from a 3/4 ton National to a Stuart 600. If you require good runnng and starting then go for petrol, Propane gas which is the best substitute for coal gas requires a lot of fiddling to get the engine running ,plus a rubber diaphram old type gas bag/regulator,I have 2 gas Gardeners with hot tube ignition,the gas setting is critical there is no rich or lean running with a gas engine,the mixture must correct.Regarding ignition,the normal type of ignition for the small vintage open crank engine was a battery powered trembler (buzz) coil with a wipe type contact mounted on the side shaft. Stuarts on their 600 (similar in style to the Wyverne) engine used coil and battery and offered at lot extra cost a magneto ,mounting bracket, and 2:1 chain and sprocket drive from the side shaft ,the magneto was geared up to engine speed to improve the spark but of course there was a "dead" spark after two of the four strokes,quite common practice at the time, the Stuart was offered as a gas or petrol engine.The buzz or trembler coil is a Ht coil with an attached pair of contacts,when electricity is supplied to the coil contacts they "buzz"and produce a shower of sparks all the time the electric is switched on,the wipe contact mounted on the sideshaft is simply a rotary switch to supply current to the coil for a short period to fire up the spark plug. The trembler coil has adjustable contacts with a built in condenser and is usually housed in a small wooden box mounted under the engine. The trembler coil is probably the most appropriate style of ignition for the Wyverne, As for fitting a modern system,its up to the owner ,its their engine and they can do what they like,though I feel its like fitting LED lights to an Austin Seven. Replica trembler coils are available.
|Thread: How big can I go with a machine vice?|
The old English Abwood vices had four bolting down slots,two in line with the jaws,two at the ends so they could be mounted on both x and y axies. the bigger the vice the heavier it gets,I dont know why the modern vices only have two slots.Perhaps the eastern suppliers copied the wrong vices.
|Thread: Drilling brass conumdrum|
Are you marking out ,then using a prick punch followed up with a centre punch and what size hole are you trying to drill,? or are you you trying to go straight in on a milling machine.
|Thread: Which slitting saws|
Keep within the recomended cutting speed and do not feed too fast,drip some high duty cutting oil eg Rocol on the saw teeth when cutting stainless.Remove the key from the arbour when using thin saws its better for the cutter to slip than shatter into lots of pieces.Make sure the collars on either side of the cutter are the same diameter to avoid distorting the saw.
|Thread: Lathe work|
I had a problem with Burnerd 3 jaw,same as the four jaw,bought new when I bought the Myford dividing head,this allowed me to hold work in the head and use the lathe 3 jaw to hold the cutters,.twenty years later the 3 jaw on the lathe was a little worn and the dividing head was not used as I had a universal dividing head for the mill.It was then that I found that the new chuck had a runout of around 1.5 thou, the one that I had used on the lathe initially had virtually zero runout. Too late to have a go at Burnerd so I mounted the new one on a back plate and got it dead true,and is still a good chuck. Manufacturers do make errors,quality is/was always a uk problem.Had a similar problem with a very expensive bore micrometer,this had two sets of jaws to cover the measuring range,this was a company purchase so it went to the standards room for calibration,one set of jaws gave a perfect reading,the second set had a serious error, and accordingly rejected. I dont know what happened as I moved on to another project.So if you buy precision tooling for your workshop ,check it over if you have the equipment to do it. Now there is a way to correct these jaws in the four jaw burnerd,find someone with a surface grinder find out the run out error on each jaw set up the jaw in the vice on the grinder with a dial gauge set the jaw with same amount of run out and grind the jaw true,do the jaws one at a time, I once trued up a 10 inch four jaw in this manner so that it could grip round material.I do not believe in using tool post grinders on a lathe,grinding dust and lathes do not mix no matter how careful you are, I once had to use a toolpost grinder at work to grind a long cylinder,and then found how grinding debris gets everywhere, being at work I used it as I was told to ,though it was never used again all the time I was there.
|Thread: Cross slide dial calibrations - opinions sought.|
All very interesting,My imperial Myford reads on radius and my Imperial Colchester fitted with dual dials reads off diameter,have got used to it,though my basic training years were on traditional english lathes . Mention is made of Henry Maudlay ,did his machines with dials indicating radius,stem from his work on screwcutting, where all threads were dimensioned by diameter ,thread pitch and thread depth, It is easier when screwcutting to have an index dial which indicates depth of cut ,rather than indicating diameter. Plus early lathes were put to many uses,eg boring and machining with work held on the crosslide,and carried on with Myford and Boxford(and others) where the dial indicating actual cross slide travel is far more useful. Apparently Maudslays lathe had an indexing dia,,but a lot of Victorian era machines only had crank type handles on the screws with no index dials,back in the 60s my neighbour still owned the engineering worskhop his father had set up to support his agricultural and thrashing buisiness in the 1880s,the buisiness closed before ww11 but mneighbour loved his steamers and retained them and the workshop until the end of the 60s. he had three lathes,two six inch and a rather large 12 inch lathe,plus small planer none of these machines had an index dial, I remember telling my boss about them,his comments were that most machines of that era had no dials,the turners worked with stiff joint calipers and steel rules and chalk marks on the handles,they never used spring type calipers,and only the foreman had micrometer.and apparently they produced good work though no doubt this is where the term for their trade was "fitter and turner".When I only had a Myford,with a vertical slide and index handwheel on the leadscrew,it would have a real pain if the crosslide did not have radius reading dials when milling .
|Thread: Firt time at indexing|
In every shop where I have worked or visited ,rotary tables are wound via the handle and worm from index to index,I think that any one found rotating the table and using the worm as an indexing plunger would soon be in trouble with their superiors.It certainly is not good practice to use a rotary table in this manner.
|Thread: Lathe work|
If it is essential to hold the bar the four jaw and the jaws are worn ,then either put some shim between the jaw and the work,on all four jaws try various thickness of shim until the the jaw grips at both ends. or hold in the four jaw chuck and support the outer end in the fixed steady,with the end of the bar running true ,centre drill the end, Then hold the work in the four jaw backed up with a rotating centre in the tailstock. Should you at some time aquire a new four jaw chuck,then use the new chuck for bar work which is gripped over the whole length of the jaw and other decent work,retain the old chuck and use it for gripping rough castings,bits of plate which have to be held a the very front of the jaws and where some abuse may be necessary.
|Thread: Spot Facing With Slot Drill?|
Pilot spotfacers or pin cutters were used on capstan lathes in the instrument trade for producing parts for microscopes and telescopes, eg the internals of eyepieces where there were bores with steps to take lenses and locking rings,material brass or nickel silver,being straight carbon steel they were run at a lot lower speed than HSS,with full soluble oil lubrication. and would make a thousand parts without sharpening,allwere made inhouse from Stubbs silver steel ,heating was a paraffin blowlamp,quenching was in a couple of gallons of hot water in a galvanised bucket,work at red heat was plunged vertically. tempering was a medium straw colour,no fancy oven just polish the buisiness end of the work with emery,heat the shank of the tool gently until the heat travels towards the cutter end ,the band of straw colour is followed by a blue band, wait until the straw reaches the tip and quench very quickly in tap water,thats how we did it.now some 60 years ago,it was crude but it worked and worked well.cutters up to one inch were made in this manner,they lasted for a long time,though they could be broken if the turret of the capstan was swung bound a bit too quick and colided with cross slide tooling. Stubbs silver steel was always marked with name at one end of the 13 inch bar,and the rule was, cut the the amount required off the other end so you knew it was silver steel,the cutter edges could be filed with very fine files,the preferred method was to use the Clarkson cutter grinder.We never used them on cast iron or steel. if it is acceptable for a spot face on cast iron to be produced by a hollow ground cutter,to prevent any digging in with cutter the lips of the cutter can be groundback to give zero rake.
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