Hi Alec

Sounds like your 4-way toolpost is off another machine and the metal under the tool is too thick,causing the toolbit to sit up too high. Pics of what you have there would help. The original Norman clamping type tool holder should hold 1/2" tool bits at centre height no problem. I would not chop the pillar off the topslide to fit a QC toolpost. Learn to use the others first and get to know the machine. Nothing wrong with using shims on a four way. It's all I do on my M-Type and my ML7.

From memory the oiler bolt is about 5/16 BSW, with the end machined to a point that fits into the bearing wedge. Bolt has a square head and a hole through the middle for the oil. I made adaptors and soldered them onto mine so I could screw drip oilers into the adaptor.

The C spanner fits onto the slots machined around the circumfrence of the round bronze rings that screw on to the front of the bearing.

Wobble couuld be caused by old hardened V belts that have "taken a set" from standing for years.

Colour, not sure. Drummonds were black originally. Myford may have changed that to war surplus battleship grey like the ML7 when they took over making the M-Type. I don't know.

There is a good drummondlathe group at groups.io with a lot of knowledgeable and helpful M-type owners there. The Files section has a lot of good info in it. Also a Facebook page on Drummond lathes I believe.

ML7 four jaw chuck could be adapted by bolting to an M-type back plate, which used to be available from lathes.co.uk some years back, but not sure these days.

ML7 cross slide and tumbler reverse and just about everything else will not fit on an M-type. Totally different design and the M-Type was a lot heavier built. Tumbler reverse castings and gears and other such accessory castings are available at times through the groups.io Drummondlathe group. But it is not something that is necessary. Myford vertical slide will fit. T slot spacing is different but you can use one T bolt and one clamp etc.

Have fun with your vintage lathe.

Hopper

Edited By Hopper on 25/06/2022 12:00:23

Your 4 way toolpost looks about the same as the one I made for mine. It takes 3/8 square tooling right on centre height. Works well. Although, I use a lot of 1/4 and 5/16 HSS anyway. Cheaper and quicker to grind up than the bigger stuff. I found carbide insert tooling does not work that well on my M-Type. Partly because the spindle seems a bit small and not rigid enough for the heavier cuts the carbide can take, and partly because mine is flat belt that slips under heavy cuts with carbide. Yet it will take 100 thou cuts with HSS no problem.

I think you will find all the Drummond/Myford M-Type chucks are mounted on backplates. The gap in the bed is longer than on an ML7 to accommodate this. And from memory the ML7 four jaw uses a backplate too. Only the 3 jaw has the internal thread in the body itself.

Beware that the ML7 spindle nose has a larger thread and register than the M-Type so ML7 chucks will not screw on to a M-type. You need the earler type 4-jaw with the backing plate and a M-type backing plate with the small thread. Not all those older 4-jaws had the bolts going all the way through to the front, but studs in the back. Another thing is the longer gap on on the M-Type. if you use a compact chuck without a backplate on it, you then have to have the carriage hanging off the end of the bed to get the tool up close to the chuck, so better to go with the backplate.

Your plan with the oiler screw sounds good. Should get you going. There is a small wedge that the screw bears on and sits in the slot in the bearing. It has an oil hole through it from memory.

Don't run the motor any more till you fix the bearing, the felt (if there is one) may be unable to soak up any oil.

You can use inserts for aluminium on steel at speeds suitable for for your lathe. Following the available industrial speeds and feeds charts for carbide on an old lathe is a mistake.

You may find that CCGT inserts are easier to source

The M type is an old machine, probably designed before carbide tips were produced. the bearings would probably be damaged if it were run at the speeds and feeds that optimise carbide tips.

For almost everything, except hardened materials, HSS will suffice. (That is where carbide comes into its own, with swarf coming off like red hot wire!. )

Possibly, for very fine cuts, HSS is the better.

Again, for most purposes, the exact clearance angle is not desperately critical. OK, the book may say 10 degrees, but probably you wouldn't notice if the clearance was actually 7 or 12 degrees.

For the cost of one carbide tip, you can but a 1/4" HSS toolbit that can be reground to sharpen for the equivalent life of several carbide tips. And HSS does not chip as easily as carbide with interrupted cuts, of if you bang it!

Probably, the ultimate in easily ground tools is a Tangential Turning Tool. You will meed a means of setting easily to centre height, but it only needs one face grinding, and you can buy the jig with the tool, or make one if you make your own. (At least two designs have been published in MEW for the home maker )

There is many a good tune played on an old fiddle!

Howard

Tangential Turning Tools and general ramblings.

If you can access earlier Issues of MEW, two designs for shop made Tangential Turning Tools have been published.

The first design was to take 1/8" toolbits. (I made up a lookalike for 5/16" and it works like a dream. )

Having a square shank, it involved milling at compound angles (Not impossible to file by hand, if you are careful ) And am not sure that all the angles are terribly critical

The second version made life easier, in some respects, because it entailed milling the 12 degree angle onto the shank, to change it from square to trapezoidal.

The jig for grinding to sharpen, is simple to make.

The Eccentric Engineering version uses a 33 degree angle rather than the 30 degrees shown for the sharpening jig in the MEW articles.

Once made, the advantage is (Apart from the fact that it performs well ) that there is only one face to grind.

Compared to carbide tips, a HSS toolbit can better withstand the occasional knock, and in cost terms provides a lot more tool life for the cost of one carbide tip.

You do need a Centre Height Gauge to set the tool easily. (Making one can be a useful learning experience for a beginner, and results in a tool which is always useful )

Making such tools (Tailstock sliding Die and Tap holders can also be a good means of gaining experience, confidence and familiarity with the machine, while finishing up with tools that can be used for years to come.

I cheated and bought the actual Die Holders, but made up the arbor and body for the tool.

You can make the main body of the tool as simple, or as complicated as you like.)

For the Tailstock sliding Tap holder, again I bought ER collets and had to screw cut the 1.5 mm pitch thread.

(A more daunting task for a beginner, probably left until more experienced )

Both these tools are particularly useful when producing fine threads, since the newly cut thread has minimal load imposed on it by pulling the tool along the arbor, rather than trying to [pull a tailstock along the lathe bed.

(I found out that the hard way trying to cut a 40 tpi Model Engineer thread!

But interrupted cuts will tend to hammer the toolbit down below centre height, so that it needs resetting.

And, HSS is no match for hardened steel, where carbide will cut it easily, with interesting, brown, blue or even red hot swarf!

Now, in addition to the ones for 1/8" toolbits, I use the Eccentric Engineering version, with the 1/4" toolbit for most of my turning work, especially for finishing.

A feshly ground tool will remove 0.0005", or less, a side for finishing mild steel.

HTH

Howard

I prefer inserts to HSS for exactly the reasons Alec gives: they potentially eliminate the need to buy a grinder and learn how to use it. Not everyone is good at grinding, so beware folk to whom it came naturally: they insist it's easy and just needs a bit of practice. Yeah right, so does learning Integral Calculus…

In practice I use both, 80% inserts, switching mainly to HSS when an unusual tool profile or very fine cuts are needed, or I'm having trouble getting a good finish.

Carbide is fussier than HSS about depth-of-cut, feed-rate and RPM. Works best when pushed hard at high-speed, removing metal 3 to 12 times faster than HSS. Though sharp Carbide inserts work well enough for most purposes, hobby lathes don't have the power, speed or rigidity needed to get industrial performance out of them.  I still prefer inserts!

Assuming the drive-train and cutter are both in good order and the gibs are adjusted, depth of cut depends mostly on the power of the motor and the material. Rule of thumb, 1HP will remove 1 cubic inch of mild-steel per minute.

I suppose maximising depth of cut might be useful when roughing out, but even though my lathe can do it I rarely take cuts more than 2mm deep (4mm off the diameter). Though there are exceptions, I find it more civilised to take cuts between 1 and 0.1mm deep, less for finishing.

Best thing to do is experiment. Get some free-cutting mild-steel bar, at least 25mm diameter. Set RPM to 10000/25 = 400 (this is about right for HSS, triple RPM for carbide if the machine can run that fast), and try taking various depths of cut over a 30mm length with a sharp tool, with minimum overhang in the tool-post.

Listen and observe. The machine should sound as if it's definitely working hard but not in distress. Nothing should be bending, lifting, twisting, or otherwise misbehaving mechanically.  Look for the best compromise between quick metal removal, controlled accuracy and good finish.

Once depth-of-cut is understood, experiment with feed-rate in the same way.

Friendly materials cut well over a wide range and are very forgiving. Difficult materials are much fussier about using the right shaped tool and getting all three parameter spot on. Some are impossible.

If you're a man in a hurry, beware of fitting a giant motor to remove metal extra-fast: the drive train will wear rapidly, and accuracy goes to pot when the frame is twisted by excessive torque. Damage done by a crash is much worse too!

By the way, don't expect to file HSS – it's too hard! Grinding is the answer.

Dave

Edited By SillyOldDuffer on 03/07/2022 13:41:51

I can sharpen HSS, but find carbide suits most things I need to do. As mentioned, it's useful for unusual shapes or form tools, but for the most part my pile of HSS cutting tools is gathering dust.

I'm sure most people could operate a treadle lathe rather than an electric motor, but who wants to do that if there is a better option?