bertiedog

Whow! ... don't jump the gun, the lathe should work from the box, stripping should not be required, you will need spirit and paraffin to clean all the protective grease off, and lots of cloths!! The first thing is to find a table that is strong, and plug it in! but first check over for loose screws etc, and turn the chuck by hand to check it's free, then put on lowspeed and run themotor for a whil at increasing sppeed, both way, leave running at medium for a few minutes and that's it The Gib strips can be adjusted, see manual, or ask here, and you are ready. The main bearing will be OK , you can check it though, after the running in. Apart from the cleaning there is little to do. The main gear could be changed to metal as per ARC, but why if the original works, something to think about later. The surfaces are hand lapped by the Chinese so leave well alone unless you are convinced the work is wrong. But you can tidy up any scratches on the parts that are raised burrs, or decide to alter the tailstock nut lock to something better, the first job. But it works fine with the nut anyway, but the option of a cam lock with a lever is there if you want it. Lubricate with light machine oil, or car oil, rub down paint with a mix of oil and paraffin.......and find something to make. The only item I would say is vital is a saddle lock, they are described in all the websites and book, you will need a block of aluminium or steel and a couple of bolts to make it, an afternoons work, or a day if you paint or polish it. any queries just ask!!! Stephen.

For all other readers, who may rarely see a dividing head, it is a device used in machining gears and similar items with radially spaced teeth, or holes etc.. The work is located super accurately on the two centres, suspended by them, and the drive from the gearbox end locked in to zero position. A "dog" engages the work to turn it without backlash etc. The handle is geared to the driven centre, and holed drilled plates allow sub division of each turn or part of a turn. With a normal worm drive any normal division to 1000 is quite easy. Obviously some common ones like 48 can be done direct from the plates, or sub divided or multiplied from others. The whole thing would be set up on the bed of a vertical or horizontal milling machine or precision column drill, to suit the work to be done. The whole idea came from watch making, where the devices date from the dawn of machinery, where clocks demand complex accurate gears in many tooth forms. A rotary table is almost the same, but designed to take chucks and collets for single sided holding during division. It can act as a dividing head as well though, with a tailstock added, and a full set of division plates. Most home machinists go for a rotary table with plate division, Vertex specialise in 6 inch ones that suit a lot of home workshop users. It is convertible to horizontal for dividing duties, or vertical for milling divisions like round rows of holes in steam engines covers. Stephen.

This gives the detials of the tapers the B&S is a constant 1/2 in taper , and the No 7 is very close to a No 2 morse. I have asked around and few collet chucks are made to fit B&S as standard, Bridgeport did them, and Schaublin list them, but you are talking a lot of money. Now do not take this the wrong way, but why do you need to mount a collet chuck on a dividing head, when most work on dividing heads is held between centres? I know it depends on the work, and all the alternatives, but usually a collet chuck would be added to a rotary table with dividing drive where it is impossible to mount between centres. This is why so many Rotary dividing tables have common morse or R3 taper mounts. A dividing head like the B&S may be able to sub divide further, to about 1000, than a simple rotary table, but the Vertex can divide to 1000 or more with the same precision, a morse centre is popped in and it acts as a dividing head. I have 10 sets of plates to do any common division to 2000, some custom to save counting the jumps!!! My own tailstock for the vertex is home made, cast for me in iron, and machined to look like the B&S type. Stephen.

The problem is B&S do not make them any more and current Chinese made Vertex clones are fitted with Morse, so the call for adaptors is very small. If it is the model O B&S then there is another problem, the two tapers are very close and a sleeve would be a bit impractical, it might work, but it would need a bit of trial and error. It appears the B&S is shallower than morse and the sleeve would make the centre stick out a long way. It may be the collet holder has an inserted tang, which might be removable, and you could interchange the tangs as needed. The only other way is to source anothe collet body already on a B&S taper, and that is going to be difficult now that the head use Morse so much. Stephen

See Ebay for Morse No one machinable morse arbors if you make a tiny ball raced centre......... http://cgi.ebay.co.uk/1-MORSE-TAPER-BLANK-END-ARBOR-NEW-1MT-/350108109911?cmd=ViewItem&pt=UK_BOI_Metalworking_Milling_Welding_Metalworking_Supplies_ET&hash=item518411cc57 Plenty of other suppliers exist, but make sure the end is machinable, in a soft state, the listing is for UK made Picador type not made any more, but he has a few in stock. No1 Morse is a popular size for smaller lathes, but bigger may take two or three in the tailstck. Myford use No2, and No3 on bigger versions. The Seig has a No2 morse, the Proxxon No1. An exception to all of this is Unimat 1/2/3..... and they have no taper in the tailstock, but a parallel plug fit, very easy to adapt the tiny live centre design to.

Ozzyo, ........further to the query on the dividing head, it sounds as if it is a Brown and Sharp,(B&S), and if like the standard B&S units it is fitted with a B&S taper number 7 or 8 for B&S number 0 and 1 and number 10 for the B&S model 2 This would have to come from B&S or a outside supplier, and by the look of the combination a Morse conversion may not be practical, the tapers are very close. It looks like the collet set will need a new number 10 taper tang to fit. I may be able to provide the taper details for the number 10, but I cannot in any way g/tee what is actually fitted. However there is another approach, and that is to strip the entire rotary dividing head, the core with the number 7 or whatever version the model has, it could be re-machined or bored out and a sleeve inserted, but this is a task for a machine shop with decent boring and grinding to maintain the B&S accuracy, which is extremely high. http://www.hexagonmetrology.co.uk/ are the name B&S trade under these days and might be able to help. Stephen.

What's the model of the rotary table/dividing head? (O&B?)if it is a standard taper in there, usually they are short form morse, but others are used, I have full lists in Machinery handbooks which may identify, but you may have to turn a sleeve as the tapers are different, and not many makers do converters from one taper to another from stock, unless a popular conversion from MT types. Most dividing heads come with an un-machined blank to fit the taper, and maybe the original supplier can help with the blank. The smaller Vertex rotary table has a number 3 morse, but the Schaublin dividing head with plates uses a Brown and Sharp. The angle can be measured by the diameter at the base and throat, measure the distance apart and trig provides the angle to identify it. I assume this is the type, I have similar, and the taper in these is morse on most, as it is used mainly for between centre work. The morse is often a half length morse and a full tang will not fit some times giving the impression that the taper is different. I assume you may know this already, and the comments are for all readers as well. Stephen.

An oft quoted objection to these methods is "I don't have a live ball raced centre" or the centre I have is awkward and too big, so lets make one in the lathe, it should take about two hours at most, given scrap materials to hand. First you need a blank morse taper, in soft steel for turning, if you have a hard one then heat as hot as possible in a propane flame ad then cool slowly, it will now be soft enough to turn. The size morse should match the tailstock of the lathe Take the chuck of the lathe off and fit the morse into the headstock, most headstock tapers are bigger than the tailstock and a sleeve can be used to convert, they are easily sourced and useful items to have, (It allows the tailstock drill chuck to be mounted in the headstock). Some small lathes already have the tailstock and headstock the same size, like Toyo, Proxxon, and Unimat, but it varies with model. Find two ball races that can take side thrust, or at least one that can, of a suitable size, say 6/8mm bore, and a case of say 10/15mm, it is not important, any diameters can be used in proportion to the final small size. Two ordinary ball races will work, after all, the side pressure for this use, is relatively light. The morse shank blank end is then turned down to leave a stub that can take the bearings, a nice push fit, not too tight, and loctite them onto the shaft as in the drawing. The lot is removed from the headstock and the three jaw returned to position. Find a scrap large steel bolt or a piece of steel about 3/4 inch, in proportion to the outer diameter of the ball races, and turn to shape the whole out sleeve, the hole will have to be bored to size, and then turn the work around and turn the cone end. This should really be done in a four jaw, but a good condition 3 jaw will do. The sleeve is then slipped over the bearing and tested that the centre runs true as the body turns, if you have used a three jaw to turn the point you might have to try again if it has a wobble on the point, but as long as it seems true to within a thou or less it will work. If the sleeve is set with a dial gauge in the 4 jaw it should be true full stop!! After testing pull the sleeve off the races and then loctite them back one, and that's it, you have a custom tiny ball raced centre. You can make this type as tiny as you want, you are saving many pounds making one, and they don't sell them this small unless very expensive clockmaker's types. For day to day work a normal larger live centre can be bought cheaply these days, the FE ones are quite accurate, but, with say a Sherline, it needs the very smallest size to not get in the way of the smaller workpieces. Stephen.

The best way with Romfords is to copy the basis of the Gibson type,(drawings posted), with a recess in the mandrel face, and the washer, to grip the rim edge. The centre of the mandrel can be drilled with a centre drill, and then drilled and reamed 1/8 inch and an axle inserted and epoxied into place, with the square end far enough out to enter the back of the wheel, the screwed part is then turned off. The wheel just slips on to the square and the disk pressed home with the ball raced centre. The mandrel should be mounted in a collet or in a marked three jaw to be able to set it up without to much hassle, but it could also be set in a four jaw. The raised edges should be sized to touch the outer rim of the wheel to grip the nickel silver tyre, not the mazak centre. Stephen.

Written both ways in Machine handbooks, but I will correct it for you......

Working with any small lathe and wheels in smaller scales up to about gauge one. The methods are well known, but act as introduction to newcomers as well to lathe uses. One of the main jobs that a small lathe is used for is producing wheels or modifying the existing wheel, taking a commercial product that can be made to conform to a tighter standard etc., or replacement of tyres on mazak cast wheels with a more suitable tyre. You can also mass produce wagon and coach wheels from scratch, maybe for P4 or less used standards like S scale. Any of the small lathes from the Sherline upwards can handle these jobs, it needs a bit of planning on holding the wheels for machining, mostly out of the chuck on a mandrel or spur point. The most common request is reduction of the flange, taking a Lima wheel as an example, the flange is about twice as high as it could be reduced to. Most of the older Lima wheels were brass, chrome plated, but it will work with the mazak chromed as well. The wheel, removed from its axle is not able to be simply gripped and the flange removed, so the first job is to chuck a bar of steel, say 3/8th inch(8/9mm metric in the three jaw, and turn a matching end on it to fit the Lima axle size,(or other). As the mandrel will be used many times it is worth reverse chucking first and putting a flange that will consistently rest against the chuck every time the mandrill is used. The stub for the axle should stick through about half way, and have the end drilled with a centre drill to allow space for the point of the ball raced centre to fit without touching the stub when the wheel is fitted. The mandrel should be marked to match jaw number one to allow return to and accurate position for each use, and the concentricity should be checked before use. Most three jaws are accurate enough, but if you want on larger wheels the mandrill could be set in a four jaw chuck for complete accuracy. The mandrel is readied and the wheel slipped on to it, now comes the hard part, getting it to be turned by the lathe, and the easiest way is a live centre fitted in the tailstock, and to simply press the wheel onto the mandrel back, with sufficient pressure to hold. The centre revolves with the work, and the wheel is very accurately held. All small lathes come with, have available, or it's an accessory from any independent supplier, a ball raced live centre, (or you can make your own in the lathe should you wish.) The flange can then be reduced and the shape of the tip filed or turned and finished with abrasive papers. When abrasives are used , cover the slideways with paper, or cloth, and remove any dust made. Only use a file if you are experienced in such work, it is classed as somewhat dangerous, but is an accepted Jewellers and clockmaker's method. The whole wheel can have the tyre removed till it is flangeless, or reduced further to take a new tyre, on for example a mazak chrome finished wheel, which lots of modern ones are. A non insulated wheel is easy it presses against the mandrill, but an insulted one should have a washer added at the back to allow the pressure to bear on the metal parts. Some Bachmann wheels have only a cast back, and some have raised surfaces and pips, so prior to re turning they would go in the three jaw, or a collet to have the back trued up first. All of this covers metal centred wheels, including Romfords, which can be turned on one of their own axles if needs be. With plastic wheels and scale wheels being returned, like Gibson, then a large mandrel face is made to match the diameter of the wheel so that the force is taken by the steel tyre, and the live centre bears on a washer made with a rim to press on the tyre, this removes all risk to the plastic, which on a spoked wheel cannot take the forces of turning. All so far is accurate flange reduction or removal, the new tyre would have to be turned and a profiled tyre shape turned to continue the process. None of the above should be beyond any small lathe, or a newcomer to turning. You can use such mandrels to hold blank wheels of your own for mass production, but usually a form tool and parting off a finished wheel is done from stock bar material, to be described later. Next part, making a profile tool or using a commercial profile for re-turning or tyre replacement.

NO, the correct/normal/every day/usual/ accepted way is the front and right way up, the others are alternatives and only shown to show what they do...it is horses for courses. If it is a Colchester 20 inch lathe it ain't going to notice anybody messing up parting off, but if you do it wrong on a Sherline it is going to protest in no uncertain terms!!!!! The Myford is an exception in some ways, it is a very fine lathe, but parting off can be troublesome to people who only have half the story, it needs to be well adjusted to part off well. This is very well documented, it has been addressed by Myfords with redesigns within the design of the lathes bed,...... the final word is parting off is OK on a good condition machine with a good operator, too often I see a badly adjusted Myford with a newcomer to lathes, and Yes, I have seen half a broken parting off tool buried in the ceiling!!! it juddered, dug in, and before he could operate the clutch the tool shattered, but it was that operator, and it might have happened on any small lathe. I was trained in engineering with Post Office Telephones(BT), STC, and Cable and Wireless, and worked later in model engineering and model manufacture, and then in optical instrument making and making lenses and scientific instrument making....and I started on lathes with my father at the age of six, on a Drummond round bed I still have, and that's fifty four years ago. Stephen. Stephen.

One other point I had in mind to mention on parting off and it involves insert tips as well, it that upside down tools clear the chips of swarf better than the right way up, .......it's gravity you know!!,... and also for parting off the geometry of the carbide insert tips breaks up the swarf finer than the conventional HSS blade grind, again combined with up side down there is liiitle chance of the swarf causing drag and inducing judder or jams. George Thomas, who designed his famous rear tool post holder for the Myford,* said a top rake of 7 seven degrees was best for general work with steel, both front mounted or rear mounted. This ties in with Sanvik inserts. The other vital point I did not mention is that the blade must be at right angles to the work, plus or minus nothing!!! Check both sides with a good miniature try square against the turned work, or a test bar in the chuck, a fraction of a degree either way, and friction builds up and the tool tip is deflected. The carbide insert parting tools are kinder in this respect, they are are only a small side length, then a thinner holder, so out of right angles does not how too much, but it still counts on finish and safety, so still check with the square. Stephen. * George Thomas's books and ME articles cover the design of the Myford saddle and its limits etc., in great detail. He was a deeply respected author and expert tool designer. I use one of his toolposts in the Warco lathe, expanded to the bigger size from the Myford series 7 type.

Your jumping to the wrong conclusion if you are thinking I am complaining about Myford, the Myford 7 series is good, very good, but it does have a flaw that I and others have commented on,, shared by lots of other makes to the same design, the upward force on the back of the saddle is taken by a plain flat surface, not a self locking V surface. If you get good parting on a Myford it is because you are working well within the limits of the machine and you are just very good at it. The Myford judder only occurs when the saddle is not locked, or the gib adjustments are poor, but well adjusted, and locked, a Myford will part 4 inch steel bar with ease. Old hands like Terry Walshaw of "The Model Engineer" advised using the rear post to drive down the saddle to sit tight on both the front and the back of the bed slides equally, a movement so small you need a good dial gauge to read it. This is because he did parting without full locking, as he was using multiple tools and did not want to lock and unlock the saddle repeatedly. I have never had a Myford I was using judder in any way, but in helping out setting up lathes for other model engineers, often came across the saddle too loose or not locked, and people would comment that they did not get on with parting off, but a few adjustments, and using the saddle lock, and all of them worked 100%. I have re-built several Myfords, from the ground up, including hand scraping the bed flat and total strip, and know every detail on them, and would have one of the machines if Myford had been able to deliver one in under 15 months in 1987, as I needed a big lathe for work the next week I opted for the larger Myford 13 inch centre equivalent from Warco. Often the problems with any lathe is the user not being completely used to using a lathe, and passing on tips like the details of parting off is not attacking a particular lathe, but providing the knowledge and tips to be able to understand why something is advised. Now it could be an annoyance to any lathe owner that has a lathe with high quality roller bearings to hear that a well adjusted Myford beats it hollow on surface finish, because even the best taper races cause harmonic vibrations than result in patterns on the cut surface. The reason I know about it was producing British Standard test peices, yes, the ones that test others!, and the surface had to be perfect, no marks, even at the reflection of laser light. It showed that you could tell from the reflection pattern whether a roller or ball races was used, and the beat frequency even told you the number of rollers fitted in the bearings. But a Myford and a Schuablin, with plain bearings, produced little or no patterns, and the Schaublin none at all when really tightly adjusted. The Myford was the next best, so do not say I do not know what work a Myford will or won't do. Stephen.

B are C are the same in effect, the resultant opposition force is towards the saddle in both cases, the "correct" way to do it. In normal front cutting by parting the force is the wrong way, but barely matters as the weight of the saddle resists it, dependant on lathe design, and the Myford/ Southbend/Colchester etc., saddle at the front is heavy. In D the same applies, and the "wrong" upward force is applied to the back of the crosslide and is less desirable. However all is academic, if the work demands multiple tools, as on a manual Brittain or Ward , where 4 to five tools may be mounted at the front, and another four at the back, just to get enough tools for a regime of cuts. You just have to place some to work in reverse. It's a very much simpler world with an Emco or Sieg etc., or the tiny US Sherline, where front parting is the normal position. As lathe size increases back parting is usual, especially for the Myford, which has the same style of saddle as the classic Southbend lathe, and suffers with front parting, due to judder, not all the time but it can happen with bigger diameter workpeices. I worked with Myford for 20 years, and my current Warco has the same saddle, but it is so heavy that it does not judder, (and locks as well.) The Colchester Student, Boxford, and larger Colchester do not judder on parting, different type of lathe bed, and my small Toolroom Lorch simply does not judder, as the whole bed is flat and it grips with V beds facing front and rear, and has a clasp lock that clamps totally for parting off, virtually making the whole cross slide part of the bed. Denham used this type of bed on many of their medium size lathes, as did Cardiff, and Brown and Sharp. You don't worry too much about judder on a Denham, the saddle weighs as much as a whole Myford!! You may notice I have had about 48 years experience on lathes of all types, I had to learn on the job, you never told the foreman you had never seen a particular lathe before, you were expected to be able to use it. Many a time I have been presented with an "unknown", and I know the manager is thinking....I bet this stumps him, but I have never been "had" except on a Holzpeffel fitted with a machine engine pattern generating head, which TD Walshaw, "Tubal Cain", of the Model Engineer magazine conservatively thought it took about 10 years to learn to use properly. I barely learnt how to do elliptical cutting let alone complex patterns to order!!! This is all why I like the Sieg, especially in the form the Warco uses, with the new tailstock, it is essentially a small Southbend in miniature, and no worst for that. Stephen.

Just had a talk with one of the suppliers whilst ordering some bits, and there are two reasons the other brand had failures, one.... The screw was done up far too tight, it needs to be secure but people were adding leverage to the bolt head, and two.... They were over extending the whole tool, one of the keys to parting is the minimum amount possible and no more should be extended to do the work,.... grip at the back, with an extended front and great force is applied to an already over stressed clamp down bolt and it can shear the body blade groove where the blade sits or even strip the bolt. These are FE made and usually OK. The full clamp type do no suffer in the same way, but again only use as much blade as strictly needed. It was not so much the small size, but inexperienced use that brought problems to light. Stephen.

Well I have used this type and they work, but they may have had makers troubles, but there is the g/tee... or going for a more expensive Glanz insert type in 6 mm size.. There are also the 6mm full clamp, where the holding force is provided by the clamping screws, should work fine, there is nothing to go wrong !!! Stephen

I hope this is clearer, and explains why B and C are in fact the same, as it is just a mirror image and still results in a down force to act on the saddle, albeit with the pivot point moved...indeed A and D are mirror as well. So front mounted in reverse will work the same as back the right way round.....to a degree, and less force than B.......phew! Stephen.

And by the way the Sieg is quite good at parting off, the troubles reported would apply to many smaller lathes, it's the method, not the lathe. A saddle lock is vital for a decent parting off experience, and the Sieg does not have one at all, only the gib adjustment. A saddle lock can be added in an afternoon, there are kits or home brewed versions. To part on any lathe the tips are:- ........ a firmly mounted tool, a locked saddle, and a slow speed, and the tool tip must be below the centre line by a few thou. The appears to leave a pip, but one side of the tool tip face can be set to leave no pip, but the bulk of the face should be shy of the centre line. On, or above the centre line, causes or risks judder as the tip alternatively skates and then digs in. For most cut off work the rake should be near zero, or slight for steel in small lathes. With normal rakes the tool digs and then relieves and again judder sets in. For amateur home machinist the other golden rule is that the parting off is not the finishing cut, many pros take pride in production work to use it as the finishing cut, but do not aim for this at first, part off and then face the work with a round nose tool, much better finish, and no pip. Also with smaller lathes, do not expect to part plain mild steel easily, it needs lubricant like Rocal, and some steel is really quite rough and tough. You would find silver steel or stainless actually easier. With Aluminium, the parting should be easy at low speed, but aluminium swarth has a tendency to weld itself to the tip at higher speeds, so use paraffin to act as cutting oil. Brass should part off dry, and cleanly, the speed can be a bit higher. Stephen.

He is right about the upside down and reverse as the object is to throw the cutting force down on the saddle when the rearpost is used and the reversed front does the same in a more limited way. (It does not seem to logically, but the bed/slide acts as a fulcrum/lever). I have used this on the small Ward turret lathes where the saddle was full of tools both front and rear all set on stops and motion regimes to do a sequence of pre-set cuts on complex items, and the parting worked better in reverse. The Myford, despite its renown, has the design flaw of a "loose saddle", you cannot adjust it tight enough to part off, without locking all the gibs tight, but you can leave them unlocked if the rear post is used, or the front in reverse, to apply down force to the saddle, preventing lift and judder.

A further web search shows the Emco 8 and 5 share the mounting system and it is like the Hobbymat, three or four nuts secure the chuck to the nose on studs. These are not the bolts at the front of the chuck, they are behind the flange which remains on the lathe.

Yes just checked the Emco has a standard number two Morse Taper mount in the head stock, how the chuck is held on it does not say, but the three bolts seem to hold the chuck to a backplate screwed to the flange surrounding the morse taper, so I assume the whole chuck is unscrewed, the retaining bolts are not meant to be removed. The other way they mount chucks on lathes is the other way round, the flange remains with the nose and the chuck has three studs out of the back to do the retaining with nuts in the way of Hobbymat. With the nuts removed the chuck comes away and you can get at the morse taper, leaving the surrounding flange in place. So it seems that the collet on the mill will fit easily, it should be number two morse, if it is number one, then a sleeve converter will be needed, ( easily sourced). Should the collet chuck have number three morse, then you are out of luck, unless the number three removes from the back of the chuck. Any adaptors can be made on the lathe and miller. Stephen.

If the lathe has no morse, (unlikely), the nose which has the three bolts should come off and a morse will be there in the headstock, if there is none an adaptor can be added on the nose and use the bolts to secure in place, but would be bulky due to the existing morse on the back of the collet being out side the head stock. It may be possible to remove the morse tang or change it to one which will fit the Emco morse ( I am sure there is one there). Stephen.

Stephen.

There's also an Alan Gibson kit of a GWR county 4.4.2 loco that appears to have parts of a pannier added to it and 060 wheels ....... http://cgi.ebay.co.uk/OO-GWR-4-4-2T-COUNTY-TANK-LOCO-BRASS-NICKEL-SILVER-KIT-/380245569129?cmd=ViewItem&pt=UK_Trains_Railway_Models&hash=item Stephen