Here is a list of all the postings Howard Lewis has made in our forums. Click on a thread name to jump to the thread.
|Thread: Dividing Head Handle|
A late friend made such a sleeve for his Rotary Table, and kindly, one for me.
Basically, he turned and bored a brass bush with the ID a few thou larger than the shank of the handle, and long enough to hold the handle back in the fully disengaged position.
He then milled away one side of the "bush" so that it would fit over the shank of the handle and hold the handle back to prevent the locating pin contacting the fingers.
Not very well described, but the finished product is a deep U shape in section.
You could even bend one from a strip of sheet steel, or aluminium, of the required width.
Just pull back the handle, drop the "sleeve" into place on the shank of the handle, and release the handle. The spring will hold the sleeve in place.
As the Haynes manuals say, "Removal is the reverse of the above"!
|Thread: Benson Vernier Height Gauge|
Yes, I would back the thread being BA, (I think that I have come across a BA thread on a Benson Height Gauge).
If its a British made measuring instrument, of a few years ago, I would expect to find, BSW, BSF or BA threads, rather than UNC or UNF.
My immediate reaction was "Make one". You can have the head whatever size seems/feels/looks reasonable.
Obviously don't have a 1" knurled head on a 6BA, to prevent shearing it off, but 5/16 to 7/16 would seem suitable to me.
|Thread: Plastic v bronze bushes/bearings|
Be aware of the corrosion problems that happen if a hygroscopic material is used with a shaft made from almost any material. A steel shaft in a nylon bush is guaranteed to rust if assembled dry. With lubrication, (I favour grease during assembly) life is much better, and friction is reduced.
Ideally, make provision to supply lubrication into the bush, whether grease or oil.
Also, if grit ,of any size, gets into the bearings, the bush being softer than the shaft will hold the grit, and act as a lap to grind away the shaft. "Plastic" bushes do not withstand shock loads too well, and will extrude.
On Leyland Leopard buses, the Glacier DU shackle pin bushes were good, with auto chassis lubrication, but the flanges extruded with the lateral loads, and had to be replaced to prevent horrendous wheel wobble and steering shake.
If in doubt, over engineer, as has been said on other threads, to "Fit and Forget"; unless you like replacing parts!
Edited By Howard Lewis on 01/04/2014 18:34:28
|Thread: Sherwood Jobber Drills - anything known?|
I have used Sherwood jobber drills for some time, without any real problems.
Cromwell supply Industry, so cannot afford to have major customers unhappy with their products.
If they relied on Model Engineers for their income, they would have ceased trading LONG ago.
(I am sure that Kennedy and Sherwood are the names for products exclusive to Cromwell, sourced, in all probability, from where they can get the best price/quality match)
I use drills with 0.1mm increments for as final tapping, having roughed out to the nearest 0.5mm with a coarser set.
Some Cromwell products seem pricey, but you almost always get what you pay for. Overall, I am not unhappy with what I have bought from them.
|Thread: Thread cutting problem|
Maybe it is the shock of the interrupted cut which causes the steel to twist. Barmy suggestion follows.
Why not make the part from round bar, to maximise strength and maintain a continuous cutting load, and cut the thread and then mill the workpiece back to 10 x 2mm (5 x 2mm for the section concerned).
This method may seem wasteful of material, but might save filling the scrap box, or a broken tool.
Hope that it works out O.K.
|Thread: Moving Machines|
A slow way of moving, or lifting machines is to "jack and pack". This is used a lot, or used to be, in mining.
If lifting in this way, DO make sure that the thing is not going to tip over, especially onto you (ANY doubts, make sure that you have an easy escape route. You can buy a new machine, but new limbs are harder to source)
My Mill/Drill was bolted to its bench(on an angle iron bearer/load spreader frame) inside the workshop door, and the whole thing prised up to fit some 1/2" round bars under neath. The bench and machine were then pushed to the far end of the shop (bear in mind mine is only about 10 feet long) using a car scissor jack and pieces of wooden packing, braced against a piece of 4" x 2" across the door way. It took a bit of time, but it placed the bench and machine, which I could not have pushed, where I wanted it. And then the rollers were removed.
The lathe had been lifted onto its bench using a folding 1 Ton crane. (The crane had to be folded to get it through the shop doorway)
The lathe had a convenient cast hole under the headstock, so the sling was placed round a piece of 1" bar through this, and under the Tailstock end, taking care not to crush the power shaft or leadscrew , and back round the inner end of the steel bar. This allowed the lathe to be moved into position as the crane legs went under the bench.
If moving a machine on a crane, only lift the machine just clear of the floor, to keep the centre of gravity as low as possible. Even then be careful, the load can swing quite badly on a sling, so it is possible to tip over the crane and the load!
Take time and be careful. Better to spend three hours moving the machine than three weeks in hospital, after trying to save a few minutes.
|Thread: Shed for a workshop - any advice?|
One thing that i forgot to say was that when it is cold outside, (below 5C, a 60W tubular heater under the bench is turned on. After 24 hours it feels quite bearable in there!
John your shop looks quite good, but set up the maximum space of shelving that you can. You'll fill it!
My shelves were once the inch thick barge boards on a neighbours house. They carry all my boxes of drills, Taps and Dies, vee Blocks, etc and need to be strong.
And I am still tight on storage space!
Don't use any form of combustion heater, they produce water vapour.
For what its worth, this is my experience.
First shed, some 50 years ago, was a 7 x 5 Baths Portable Building, with a corrugated asbestos roof. With the bench tied to the framework, it cost a fortune in replacing glass when the thing flexed as I heaved on things in the vice.
Second was supposedly 8 x 6 (It was externally, but the 50mm framing meant that the internal size was about the same as before)
Neither was insulated, and rust was a problem. The oil put on the bed of the Myford was often milky when I next went in.
As already said INSULATE!
Current workshop is ten, nearly eleven years old, 10'9" x 6'9" (largest that would fit between the fence and patio wall, one way, and the back door and a tree the other. S W M B O was not going to have either the wall or the tree relocated!)
Framing is 50mm, with 19mm T & G outer cladding, glass fibre insulation and 12mm ply inner cladding.
Only the 3/4" ply floor is uninsulated - BIG mistake, cold feet even with industrial plastic matting.
Sits on five 8" x 2" bearers sitting on slabs on sand/cement. Another mistake, should have been concrete, preferably reinforced, to prevent slight "heave" as humidity alters.
The lathe weighs about 6 cwt, (300Kg) the Mill/drill about 4 cwt (200 Kg) (and it sits on a bench of about the same weight). Then there is the weight of the steel bench from door to the mill bench, plus tools and material.
So there is a lot of weight in there.
Roof construction is 12mm ply on each side of 50mm frames, with glassfibre insulation, with under felt and topfelt, secured with bitumen, so no nail holes.
Pent roof, is 8' high at front to allow room for belt cover opening, and drawbar removal from Mill/Drill, 6'6" at rear, to drain into guttering. Water runs into a butt, used by Chief Horticulturist for the garden.
Must be due for refurbishment shortly
No windows, (security and I'd only have put shelves across them anyway)
Ventilation is by a 6" fan with a rainproof outlet., and fixed vents very near to floor level.
Cost for the basic building , in 2003, was £1600, having been sub assembled, transported some 50 miles, and finally insulated and fully erected on site.
Heating is provided by a thermostatically controlled 240V 2 Kw fan heater which runs for about 10% of the time, even with ambients of 5C outside. Location is U.K. - East Anglia.
As predicted, a lot of the time, I work with the door open, not needing the heater.
Over the ten and half years life, almost no problems experienced with rust (one very small patch on a drill chuck, and another similar on the three jaw chuck)
With regard to security, as already said, no windows; the door is a second hand fire door with a six lever lock.
It is set off centre in one end, to match the 18" wide fitting bench, and to allow a decent width aisle.
I made up my own hinge bolts by turning the head off some No10 wood screws and screwing them into the door using a drill chuck, to leave about 1/2" protruding. By half closing the door, the frame is marked to drill the holes.
Power comes from the utility room via a RCD, to a ring main with eleven dual metal clad sockets (The one supplying the inverter for the lathe is a suppressed type to minimise electrical noise being fed back into the mains).
A battery back up, mains drop out, emergency light is mounted high up at the end remote from the door, to provide light for safe exit in the event of power failure.
The radio is hardly ever used, but the digital clock is useful for keeping track of meal times; as is the intercom to the house!
Lighting is by two ceiling mounted independently switched 65W fluorescent tubes, with an ex industry worklight over the vice on the narrow fitting bench, similar ones, each side of the Mill/Drill. All now fitted with LED lamps.
The lathe came with a lamp which had an appetite for the 24V 50W Halogen bulbs. Filling a couple of slots into the reflector improved ventilation and GREATLY extended lamp life.
Hope that this is of some help to any readers who wish to build or update their workshops.
Edited By Howard Lewis on 28/03/2014 11:51:24
|Thread: Repton RT1 Ball Turning Tool|
I bought one recently (being tight fisted, it seemed expensive - but looked a good piece of kit).
It is nicely finished, with minimal clearance toolholder to toolslide. (Made a packer to bring the toolbit to centre height and bent the operating arm (tough material - silver steel?) upwards to clear the clamp arm on my four way toolpost; probably much easier for folk with with Quick Change Toolposts.
The tool carrier slide rotates on a pretty substantial sealed ball race.
Made up a fixture clamping in place of the tool holder, to allow me to use my centre finder to position the cross slide on the centre line of the work piece). I then set the toolbit against the workpiece, and applied the cut by means of the topslide, along the axis of the lathe.
The instructions seem to indicate zeroing the cross slide dial with the toolbit on the centreline, retracting the cross slide, and then putting on the cuts with the cross slide until the dial reads Zero again, to produce a pure spherical end.
This may be a completely needless exercise on my part, due to not understanding the correct way to set it up, but it works for me!
Having used it three or four times, it worked well, (0.010" cuts without any chatter), on some steel (50mm dia studding) that did not seem to like delivering a good finish with any tool, to produce a hemispherical end on the workpiece.
Aluminium was a doddle.
The minimum diameter will be whatever is smallest diameter of material that you are turning. Obviously, to prevent problems such as spring, dig ins (and resulting scrap) the cut needs to be matched to the size and hardness of the material being machined.
Just for the fun of it, tried making a concave (which was impossible with the previous tool because of chatter and dig ins. Maybe I did not grind/set the toolbit correctly?).
No problems, so am am pleased with it, although it will probably not see very much use.
Like all tools, when you need it, almost impossible to work without it, but indispensible if you have one.
|Thread: BOTTLE ROCKET|
At school we were persuaded to follow through the proof, that for maximum range of a projectile, the launch angle should be 45 degrees, (as has already been reported, so practice seems to confirm the maths).
As soon as you add wings, the lift / drag ratio intrudes into the maths and aerodynamics
The propulsive effort on is based on the pressure difference between the contents of the bottle and the atmosphere outside, so maximum range, I would suggest maintaining that force at as high a level as possible greater than the drag forces.
This seems to have happened already judged by the structural failures!
The optimum would seem to be just strong enough to withstand the drag and lift forces, so the aim should be to minimise drag from any source, whether shape, surface finish, aerofoil section or angle of incidence.
Less parasitic drag ought to allow a reduced angle of incidence, and so less drag from theat source. Could be a virtuous circle, but don't believe in perpetual motion or anything like that1
|Thread: Efficient Workshop Heating|
Was Russ B speaking (writing) in tongues? As a fully paid up Luddite, I did not understand his last post. maybe the language was computerese.
Seriously, ANYTHING that oxidises a compound containing hydrogen or even just plain hydrogen, will invite the rust fairy to take up residence.
Any oxidation of hydrogen results in water, and even in vapour form, in the presence of oxygen, ferrous material starts turning to rust, or one of the other oxides of Iron.
So woodburners, paraffin (kerosene), or gas or oil heaters, keeping pigs, or chickens in there as a source of heat is out. Even human beings should be excluded, (no good standing there waiting for the shop to warm up to working temperature) since they exhale water vapour and evaporate water as perspiration.
So now you will need additional power to run the dehumidifier!
How about combining wind turbines and photovoltaic panels, (or even wave or tidal power - if you are near the sea / hydroelectric if on the banks of a river) to get low cost energy (Low cost ignoring the capital input)?
Lots of insulation is a good starting point, to retain whatever heat you can input to the shop, including heat from the motors and lights.
To offset the energy costs, make and sell something for which people are prepared to pay a silly price, and then try not to laugh too loudly as you go to the bank! But keep an eye on the market, and think up the next wheeze!
|Thread: Lathe Tool Inserts|
For inserts , and holders, try J.B. Cutting Tools.
01246 - 4128110
As a customer, I have always found Jenny to be most helpful.
I used to have problems making telephone contact, having to leave a message on the answerphone.
Last time that I spoke to her, she said that the E mail was now up and running.
JB attend most of the shows, the next one, of which I know, will be at Spalding, 26/27th April, and then Harrogate in May. So if you can get there you can discuss your needs, face to face.
Also look at Chronos, Warco, Chester, or other major suppliers, as possible sources of inserts.
|Thread: Is it just me?|
Eye halve a spelling checker
It came with my pea sea
It marcs for my revue
Miss steaks eye kin not sea.
Eye strike a quay and type a word
And weight four it too say
Weather I am wrong oar write
It shows me strait a weigh.
As soon as a mist ache is maid
It nose bee four too long
And eye can putt the error rite
It’s rare lea ever wrong.
Eye have run this poem threw it
I am shore ewe are pleased two no
It’s letter perfect all the weigh.
My chequer tolled me sew.
|Thread: QCTP for Warco WM240 Lathe|
Interesting comments on QCTPs and their quality!
I keep wondering about one for my Engineers Tool Room BL12 -24 (Warco BH600/Chester Craftsman lookalike).
But having managed with three tools in the Front 4 way, and another three in my home made 4 way Back Toolpost, for ten years, maybe the need is not really that great, and a spend circa £250 is a bit off putting.
(I made a tool height setting gauge to speed/ease setting Front and rear mounted tools to centreline)
Also, my shop being compact/congested (take your choice) where would I store the spare holders?
The shelf above/behind the lathe already carries Drill Chucks, Running Centre, Faceplate, Catch Plate Steadies, and Collet Chucks, so no room there. And don't even think about the storage spaces beneath - already fully used!
So votes For, and who Against please.
|Thread: Spindle nose size|
For a table giving details of Morse, Jarno and Brown and Sharp Tapers look at
The suggestion to put a bar in the 3 Jaw chuck and turn a centre is a good one. The centre will be on the REAL centre line if the headstock. If it is marked in line with say, Jaw 1, before removal, it can be replaced with reasonable accuracy. Or clock the bar in a 4 Jaw as accurately as possible, turn the centre, and then reclock to centre it with a DTI on all subsequent uses.
BUT before aligning the Tailstock, do make sure that there is no twist in the bed, otherwise the Tailstock will only be accurately aligned at one point on the bed, and you will be unlikely to be able to turn parallel over any length.
To check and adjust, either :
1) Use a sensitive spirit level on the cross slide - assuming a flat machined top surface, and check at Headstock and Tailstock ends.
Or 2) Lay the level on the ways, (use parallels if your lathe has Vee/Flat ways, and work off the flat ways for the Saddle and Tailstock)
Be aware of the danger of wear on the bed affecting the results, so use the extreme ends, which, not being traversed by Saddle or Tailstock, are less likely to be worn, if possible!
The level does not have to be ABSOLUTELY level, the essential thing is adjust/shim the lathe feet, so that the same reading is obtained at both ends, on unworn areas of the ways, to ensure that there is no, or absolutely minimal, twist in the bed.
3) The Operator Manual for the Myford 7 Series tells how to check for, and to remove twist by machining and measuring a test piece held in the chuck.
Which method you use depends on the configuration of your lathe, and the facilities that you possess, or can borrow.
|Thread: THREAD IDENTIFICATION|
It was not unusual to "buy in" an engine from another, usually larger, manufacturer.
Morris used Hotchkiss engines, for instance.
In the late Thirties, the British Salmson was a bit of an All Spare Parts, using a Salmson engine, Morris gearbox, and Ford wheels, so threads could be a real mixture.
That sort of thing persisted even in the sixties, carrying over parts from earlier models.
The Leyland Leopard bus/coach chassis was to Unified standards, but the Leyland 0600 and 0680 engines fitted, and their gearboxes, and axles were to the previous BSF/BSW standards. Brake adjusters from the BSF/BSW standard Tiger Cubs were interchangeable, so onc avehicle was in fleet service, one side could be A.F, and BSF size hexagon on the other!
And when, in the late 60s, the Overhead Cam 500 Series engine to metric standards was fitted, some hardware could be to a third standard. It just depended on which "era" the part the part had been designed.
So don't be too surprised by what you find!
The engine is French, so metric threads could reasonably be expected.
To my mind, unlikely to be 9/16 SAE, which is an American standard. Did SAE standards even exist that long ago?
However, as already said, in the early days like the twenties, standards probably were not so rigorously followed, in the motor industry, so it is likely that it could be a bit of a special.
It is not a pipe thread is it?
The Austin designed 803cc A Series engine used in the A30 and the first OHV Morris Minors, during the 50s used 1/8 BSP ball ended screws, with a 7/16A/F locknut , as the adjusting thread on the Rocker levers, and this probably carried over onto the Mini.
1/4 BSP is Whit form, 0.518 (13.157mm) OD and is 19tpi, which might be a possibility.
The French STILL use BSP threads for plumbing fittings such as Taps (Faucets) , referring to them as "Half Gas" , or whatever, size fittings.
|Thread: Mercer Dial Indicator|
You have a useful piece of kit there.
The black rectangular bar, (with the 1/4 or 5/16" spindle attached) can be fitted onto a Height Gauge, for use on a Surface Plate or table. It can also be clamped (carefully, and preferably protected on both dises) in a toolpost on the lathe.
The clamp will allow it to be fitted in a variety of places, but as has already been said, not to Surface plate or table.
The DTI can be used as a normal Plunger Clock, or as others have said, to check run out, (or position) of bores, using the pivoting accessory.
Quite versatile, you will find it very useful as time goes on.
Well Done for a good find!
|Thread: Faceplate was the cause|
If Becky can find (Borrow? But keep swarf out of it!) a Ball Race (or even the inner track of a Taper Roller Bearing), of the right size, in good, or preferably new, condition, this would probably be a splendid spacer?
|Thread: Gear cutter help|
A while ago, I had to make a one off 1 Mod 15 tooth gear, but had only a 1.25 Mod cutter.
After completely messing up one blank, I reduced the depth of cut shown on the cutter by a factor of 1:1.25, and a useable gear resulted.
This is theoretically wrong, but it sufficed for that particular application.
So, if you can get a 14.5 PA cutter, even if it is 1.25 MOD, you MAY be able to bodge in a similar way.
"Where needs must" and all that!
|Thread: Faceplate was the cause|
For what my advice is worth, try the following.
Before fitting any Chuck or faceplate, or anything else, to the Mandrel, always ensure that the thread and register are clean. Don't forget the thread in the Chuck or backplate, also!
An old toothbrush is handy for cleaning threads, (or Taps) in this way.
1) Screw the Faceplate onto the Mandel, (it may be worth marking, after skimming, the Faceplate and the Mandrel - if possible, so that in the future you screw the Faceplate onto the same point each time), and then lightly skim the face of the plate until it cleans up all over.
2) Having done that, then lightly skim the Outer Diameter of the Faceplate, until that just cleans up all round.
Those operations should cure your Faceplate problems.
If the three jaw, or four jaw chucks wobble, I suggest that you remove the Backplate. If the backplate has been removed previously, there ought to be pop marks on Chuck Body and Backplate that are in alignment.
Are there? Or if they are away from each other, remove the Backplate, clean the plate and the register in the chuck body, and refit it with the marks aligned, and check if it still runs out or wobbles when fitted on to the Mandrel.
If the Chuck Body and Backplate have not been marked, BEFORE separating, pop mark each one with the marks close together, so that when refitting, they go back in the same relative position.
Screw the Backplate on to the Mandrel and again very lightly skim the face until it cleans up all over.
Do not skim the Outer Diameter, or you will lose the concentricity of the chuck.
Remove it from the Mandrel, wash or wipe it clean, and refit to the cleaned register in the Chuck Body.
Incidentally, do not expect a workpiece held in a three jaw chuck to run absolutely concentric. A good chuck will be within 0.005 inch, a bad/worn one may be anything up to 0.030 inch or more.
If there are diameters or bores that have to be concentric, machine them at the same time, without moving the workpiece.
If this is not possible, then for the second operation(s) the piece needs to be held in the four jaw chuck and the original diameter clocked to run true before starting to machine the later ones.
Sorry if this latter bit is what you already know, and do, not trying to teach you, or anyone else, to suck eggs!
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