Member postings for Graham Meek

The pockets were milled using a Boring Head and a tool similar to a parting tool, slow and steady wins the day. A large Tee-slot cutter could be used but this depends on the milling facilities and it is not for the faint hearted.

Regards

Gray,

Hi Emgee,

The original Emco collet attachment that I had, gave me the dimension that I had to beat as regards overhang. From memory my attachment is something like 8mm shorter. This may not seem a lot but it does make a difference.

Regards

Gray,

Having owned and used the Emco collet holder for the Compact 5. I was not happy with the amount of overhang that the factory original had. Nor was I taken by the wasting needed to get the bolts into place.

I therefore set about designing something which has less overhang, is more rigid due to the cut-outs for the capscrews and uses a smaller collet closing nut. The result is one more compact unit which uses the same ESX 25 collets.

Regards

Gray,

Hi Alex,

Your last statement gives a clue as to where some of the error lies. The loading of the belts on the U3 is quite high and this is taking up some of the play in the spindle bearings.

I would also want to check that the Quill is parallel to the column. Shimming the Column you say has little or no effect. This I would expect and leads me to think the Quill is pointing either towards, or away from the Column, (you did not say where the largest error was in this plane)

Resting the Column, and Mill Head, less motor on your larger mill table. Place vee blocks under the column if you have them or two good parallels and place clamps over the Column, but do not tighten. Adjust the mill head to be parallel to the table. Juggling the sizes of the parallels to be the difference in radii of the Column and Quill will make this a quick and easy set-up. Then clock the Column to be parallel with the X-axis and clamp. Move over and clock the Quill above and below the milling head. The Quill will need to be clamped and you will need to raise and lower your Z-axis. One, to get the high spot over the Quill and two, to clear the mill head casting when you traverse the X-axis.

Don't be tempted to clock a Silver steel bar in the collet or drill chuck for the above test. This will introduce further errors due to the type of work holding used.

While at this setting put a clock on the Spindle, at the Spindle nose and wiggle it to and fro. This will tell you what play is present. From what I remember this spindle runs in one long Oilite bush.

Regards

Gray,

For those following this post John has added the gear teeth to the 3D view. For readers who would like further details in the form of drawings, I am currently preparing an article for MEW to be published shortly.

Regards

Gray,

I had a similar problem many years ago when I first had my Emco F3. My solution was to cut holes in the floor using a hole saw at the machine hold down bolt locations. The concrete beneath was drilled to take an M10 Rawl bolt anchor. Studding of the correct length was then inserted and a large nut and washer tightened onto the concrete. Using a couple of layers of damp proof membrane between the concrete and the washer, and being sufficiently large enough for what comes next.

A piece of steel tube was then inserted into the hole in the floor and level with the floor surface. This was filled with some concrete and troweled flat. Silicone sealant around the tube floor joint made everything neat and tidy.

Due time was allowed for the concrete to cure and then the machine was installed and levelled.

When I moved from the shed into my current workshop, the steel tubes were rotated using a chain pipe wrench and this undid the nuts, with hindsight I would use wing nuts now. After removing the steel concrete distance pieces, and tapping the M10 anchors after inserting a bolt, this allowed the Rawl bolt anchor to be removed and the holes were then filled with some grout mix.

Regards

Gray,

Yesterday was a good day, I managed to cut the Tufnol gears as well as some Delrin ones. When I started out to do this project I did not know I had the Delrin, so when I chanced upon a billet yesterday, I thought why not make a couple more spares.

Above is the finished assembly and some spares, note the M3 Grub screw to lock the Ring Nut at 12 o'clock. I find clicking on the photo gives a better view.

For comparison the new Spare part on the left and the Original taken from my FB2.

Lastly machining the Keyways in the Delrin gears. The Spare Gear assembly is driving the machine and the Emco Original. Just to show the gears work and to remove any doubt about suitability.

While the gear produced yesterday is not a true Helical Gear, the FB2 is not grumbling about the fact. There is certainly no difference in the noise levels or the backlash between the motor gear and the Spare. If anything it may be very slightly less.

Regards

Gray,

Edited By Graham Meek on 07/07/2021 13:25:18

The first operation today was to clock the Test Mandrel parallel to the table.

After which the Column of the milling machine is rotated through 90 degrees and the Test Mandrel clocked parallel to the Y-Axis movement. The Mandrel was again clocked over the top to ensure that it was still parallel with the table.

This view shows the Dividing head repositioned to the other end of the table nearest the table feed motor. The Over-arm support for the arbor has been added as well as the Centre support bar on the Dividing Head. The cutter was set using the scribed lines from yesterday and a trial cut taken to see if the cutter was equally disposed about them.

Lastly a close-up of the witness mark. Tomorrow I hope to cut the gears in earnest.

Regards

Gray,

It has been a while since I posted details about the FB2 Tufnol Gear 47. John Slater has kindly produced a 3D view of the proposed design which I am currently working on.

Emco press their Tufnol gear onto the arbor over a coarse knurled diameter. The gear is retained with what I presume to be Epoxy glue from what I can see. I would expect the gear teeth are then machined after the parts are assembled.

Trying to make the gear separate and pressing this onto a knurled arbor did nothing to inspire my confidence in maintaining any form of concentricity.

To this end it was decided after quite some debate between John and myself to drive the gear with two face keys and retain the parts together with a Ring Nut. This type of construction lends itself to the use of other materials for the gear, such as Delrin. Which might present problems if the assembly was just glued together. Without that is resorting to some form of exotic glue. The Ring Nut will be locked on assembly by drilling an tapping M3 through one of the Peg spanner holes, (one that is not over the drive keys, hence the need for 4 spanner holes) and inserting an M3 Allen grub screw.

The Dividing head has been rotated through 8 degrees and the DTI is being used to check the angle over 30 mm of cross-slide travel.

The Mandrel to mount the gears is next checked for concentricity and adjusted using the GHT, Versatile Dividing Head method.

Once the gear is assembled with its black Delrin backing piece, (to stop the Tufnol delaminating during cutting of the Gear) two lines are scribed 0.2 mm above and below the centreline. Similar lines are already marked on the width of the gear blank. After which the gear blank is rotated trough 90 degrees to get the marks at TDC.

These will be used to centralise the cutter over the blank. The cutter needs to make contact in the 0.4 mm square. Once that is, the FB2 has been configured for Horizontal work which will have to wait until tomorrow.

Below is the double side Peg Spanner to fit the Gear and the FB2 Quill Assembly,

Regards

Gray,

Hi Robin,

Glad to hear my few words have shed some light on the problem.

From your photograph above the Main Body of your QC system is the full width of the topslide. A 4 tool Turret, (usually supplied these days) usually overhangs the width of the topslide by a small margin. On my Maximat it is about 2 mm.

The Tool Holder length on your system sits outside the Main Block, and the cutting tool extends beyond the Tool Holder. From this, and because of all these projections, the topslide has to sit nearer the operator on larger work. Nearer than the Lathe manufacturer intended for that particular diameter of work when using the standard equipment.

When working on smaller diameter work all the cutting forces are working between the bedways, where they should be.

As a rough rule of thumb the tool holder length should be the same as the standard 4 tool Turret.

Above is the Hardened & Ground Tool holding system I made for my Maximat back in the 1980's.

Before I went over to the 4 tool Turret, (the Dark Side)

You will see the tool projection or overhang if anything is less with my QC system, as the length of the QC block is less than the width of the 4 tool Turret.

Regards

Gray,

Going back to the original post. I would like to see a photograph of the toolpost set-up.

My reason for asking is as follows.

I have seen in the past where some folk in their pursuit to have interchangeable tooling, have gone for a unit which is far too big for the lathe in question.

Such set-ups mean the main cutting forces on larger diameter work are not taken by the top surfaces of the bedways front and back, but by the front shear and the rear under-bed shear. The top rear bed surface taking no load at all. In this situation the carriage floats, which induces chatter. This effect would be reduced on smaller diameter work, ie 2.5" work as stated, because the geometry of the lathe tool is then working where the manufacturer intended.

Generally,

Light cuts and carbides do not usually go together, unless it is a tip specifically designed for it. I use Sumitomo T12A inserts which have a ground profile and a small tip radius. They work well on light cuts and leave an almost ground surface finish, especially on EN1A.

Geared Headstocks struggle in the surface finish department. That is why most high end lathes use belt drives. My own Emco Maximat Super 11 which has ground tooth profiles on the headstock gears will produce the type of surface finish shown in the opening caption. Over the years I have learned how to overcome this. Nine times out of ten I go to a lower speed and it disappears.

Regards

Gray,

Edited By Graham Meek on 02/07/2021 11:55:18

From my days of owning a Myford ML10 this hole needs to be either bored or reamed 5/8" or 15.87mm, (15.90mm is top limit on a H7 hole). The finish left by a drill will hardly be good enough. There is also an Oilite bush present in the original Myford assembly for the threaded part of the leadscrew to rotate in. Remember the clutch continues to rotate when the leadscrew is disengaged, or stationary. Without the clutch the normal leadscrew rotates in two Oilite bushed pressed into the Bed. Thus the free end of the leadscrew needs some sort of bearing to support it, as the clutch body rotates. Steel on Mild steel is not a good mix without plenty of lubrication.

Regards

Gray,

Thanks Neil for adding the PDF's

Regards

Gray,

There is one Quirk that has plagued me with the FB2 over the past 35 years or so. That is a growling noise in the 1100 RPM range. I must add that my machines have always been Single phase, so I cannot say if this happens on the 3 Phase machines.

One machine I had early on would also exhibit this characteristic in the 680 RPM range. In all cases the noise would disappear as soon as some cutting forces were present, only to reappear when the machine was running light. I have postulated an umpteen theories over the years as to why this happens. None of the remedial fixes tried for each theory, had no or little effect. On one machine the growl would only start when the machine was warm. My current machine would growl what ever the temperature of the machine, or the workshop.

Changing the viscosity of the oil and the oil type, have had little or no effect. A recent overhaul showed the Sliding Gear, (Part No E3A 010 060) and the Gear Bank (Part No E3A 010 070) had signs of wear due to the misalignment of the selector arm. All of the other gears were in perfect condition. Even showing signs of the original grinding marks on the gear form. Replacement gears made no effect to the growl once the machine was reassembled.

A couple of weeks ago at long last the Penny finally dropped. The FB2 uses a Helical spring around the upper part of the Spindle to return the Quill. One end of the spring rests on the splined drive gear, the other rotates with the spindle via a spring seat on the spindle. There is some play between the splines but as my machine parts are with-in drawing limits it cannot be from wear.

What I believe is happening is that the spring being a torsional member is allowing the spindle to oscillate on the splines due to the design clearances. When the spindle is loaded the clearance is taken up. I also believe the Cyclic nature of the Single phase motor adds to this, in the 1100 range.

Having postulated one more theory I thought I would add the splined spring seat above to the spindle. The splines on this seat are a nice sliding fit over the spindle splines but with hardly any play. The machine has been used quite a lot over the past couple of weeks and so far there has been no growl. If anything the machine seems quieter throughout the range, but I may be suffering the placebo effect on that one. One can hear a cyclic variation in the tone of the machine which could not be heard before in the 1100 range.

Regards

Gray,

There is one omission in the GHT plans with regards to the Retracting Topslide. An Erratum appeared some time during the articles publication in ME, but it never was included in his book. At least not the First Edition.

Myford provide a cast recess in the topslide casting to clear their adjustment collar. On some castings this recess is not long enough to allow the fully designed retraction. I do not know if Myford altered this when they remodelled the topslide. This may have been accommodated by Myford's, as there were very close links between George and Chris Moore.

Regards

Gray,

Hi Greensands,

Please find attached the drawing of the FB2 Dividing plate as promised.

Regards

Gray,

(I have provided PDF's on both the above drawings, and hopefully they will be loaded later.)

Edited By Graham Meek on 13/06/2021 13:07:10

Hello Chiz,

Please find above the details you need, I have managed to get the drawing done a bit earlier than I expected.

Regards

Gray,

Hello Chiz,

Sorry for the delay in getting back to you and welcome to the Forum.

You are going to have your work cut-out on restoring the FB2, but it will be worth the effort.

I am due to take another FB2 apart next week. I will make a drawing of the part and post it on here sometime next week. From memory the part has two Left Hand threads and quite a large hexagon for such a small thread.

Regards

Gray,

In the photograph above.

In the hold down slot which is supporting the Sector Arms is the head of a slotted grubscrew. This grubscrew limits the rotation of the eccentric. This is used to adjust the depth of engagement of the worm. Once set, it will last for years. It also allows the worm to be swung out of the way when the table is used for direct indexing.

It also retains the eccentric bush endwise. If you can pull the worm assembly out when the M6 capscrew is released then the grubscrew is not there.

Regards

Gray,

Hopper,

You just about summed it up in your last sentence.

Gray,

Generally this joint was doomed to failure right from the start. Anyone who has made a glued joint will know that the contact area is the key to a successful joint. In other words there needs to be a lap joint, or flange, to increase the surface area for the glue.

An internal flange on the spout, combined with an electrically conductive glue to act only as a sealer. Would have made it possible with the open design of the spout to internally spot weld in 3 places. Problem solved and the job will last for ever. Thermal conductivity from the kettle body to the spout would be possible through the spot welds. Plus the electrically conductive sealer would more than likely conduct heat equally as well.

On the reverse of this design is the possibility that the joint was designed to fail, but only after the element had expired. In which case it would have been a perfect design. If you cannot boil water, you cannot be scalded when the spout falls off.

Our kettle being a very rare exception in Jug Kettles, in that the body failed before the element.

Regards

Gray.

Michael,

It is not surprising if you live in Gloucestershire, and I would have been disappointed if they had found in my favour. The outcome was entirely what I was expecting.

As I see it today, the public have no redress in the UK for any faulty goods, other than when they are under a guarantee. The chance of injury from this item is very high should the spout eventually drop off. Even worse if the spout becomes partially dislodged as this will redirect the hot water back towards the holder of the kettle.

I am considering writing to my MP on the subject of faulty goods. I also think there ought to be a time limit for manufacturers to respond. This multi-national manufacturer was blaming staff shortages due to Covid, and only responded after the Trading Standards were involved, some 4 months later.

They were also saying that they did not make the kettle, and I would have to take this matter up with the manufacturer of the kettle. It appears the name on the Kettle has no bearing in this instance on who made it. Yet in the same paragraph they said they extensively test their products.

Regards

Gray,