Member postings for Hopper

Carbide tooling does not have as sharp an edge as HSS, so it requires more force to cut, which puts more pressure on the job. This causes the job to deflect and give poor cutting and poor finish. Your test piece is a bit too long and too thin at 20 x 200mm. Usual standard is 25mm x 100mm, or maybe 150mm maximum. Also stainless steel is often problematic to machine nicely because of work hardening on light cuts where the tool rubs.

It looks like you have achieved a good result in the end. Good stuff!

Edited By Hopper on 19/03/2023 01:06:43

There was such an explosion of a brand new boiler in Tasmania in the 1970s. Newly installed steam boiler in the laundry of a convent was hydostatically tested late in the day and the gags left on the safety valves, pressure gauge and high pressure cut out switch. Next day it was fired up by someone who did not know this, and left to come up to pressure. It exploded killing 8 people and injuring dozens, wiping the laundry off the face of the Earth. Estimated pressure at explosion was 600 to 800 psi. Story here LINK

Although, I am guilty of having a good squiz at other people's workshop in the background of pics just to see what they have and how it is all set up. Fascinating to see different workshops. So that is part of it, but certainly not for every shot.

The best I have found is large squares of coloured craft paper/thin cardboard from the stationery supply section of the local newsagent shop. But they are not quite as big as I would like them to be. I tried some old bed sheets I keep in the shed for motorbike covers etc, but as Neil pointed out in his article, they tend to show up every wrinkle and ruffle and inevitably have oil stains etc on them so not much of a success.

A large sheet of thin MDF board with white melamine surface on one side works ok too, but a point-and-shoot camera's automatic controls try to expose everything to come out a 50 per cent mid grey colour, including that white background surface. Resulting in the whole pic being underexposed. So you either have to adjust the camera ISO setting to compensate, or be careful to set the camera to auto-expose for the small area in the square in the middle then make sure that square is containing only the job in hand, not large chunks of the white background. Much easier to use a mid-tone background like the coloured cardboard sheets.

Well he would have been able to fit the crutch up spindle hole on a Chinese lathe, which would make the job easier than moving the fixed steady up the bed every time you turned a few inches of the crutch into swarf on the trusty Myford.

Well, Jason has already provided the info on how to find it, but here is the specific link REQUESTED LINK

Type in your thous per inch at the left and the answer will appear on the right in microns per metre. Easy peasy.

Edited By Hopper on 18/03/2023 09:05:22

I agree completely. A glance at a picture of a completed tool will tell the experienced operator most of what he needs to know about how to make it. Sitting through minute after minute of talking head intro then as you say, every hole being drilled, is a painfully slow way of learning anything new. Magazine articles with good pics have the massive advantage of showing the overall finished item first up, then pics of how the trickier bits were done, then if you want specific detail you can scan through the text to find the relevant paragraphs.

Seems to be about the same ratio of text to photos as most other magazines these days. Fact of the matter is that today's readers will not look at large solid walls of text. Eye-tracking research shows readers mostly look first at pictures, then headlines and photo captions, then maybe the main text, if you are lucky.

And a photo really is worth a thousand words when trying to describe a mechanism or how to do a machining operation or to set up some tooling. It is obvious at a glance very often. Not always when hundreds of words are spent trying to describe the same thing. I often look through old copies I have of ME from the 1920s through 70s when photographs were a luxury. Some of the written descriptions of how to do a job leave me beaten. I simply can not follow them. A pic or two would have made it all instantly clear. Let's not go back to the bad old days!

That would be Australia, over-regulated to the max. "Leading the world in safety" -- and red tape.

I made the traditional threaded "bobbin"-cut-in-half repair piece for my M-Type out of plain brass. It seems to have lasted well with no signs of wear yet. It was my only lathe for about five years used regularly for hobby work, including making my fabricated GHT versatile dividing head before I got the ML7 and shared the love around. So quite happy with the brass, plus it is supposed to be gentler on the leadscrew. Soft solder seems to have stood up well too, no doubt due to the shoulders at each end of the "bobbin" taking the load.

Tim, it was the T150's same "elephant foot" tappet adjuster holding the ball bearing with flat ground on it that flummoxed me. I was convinced I had done exactly what you had done and rotated one of the balls inadvertently and that was coming around and rattling. But no sign of it on checking so concluded something terrible was amiss.

So I learned at a tender age to always check the simple stuff first when troubleshooting. Could have saved days of anguish and permanent oil leaks if I had looked at that tappet cover the way the old man did -- instantly.

Had a good run out of that Trident otherwise. Other than wearing out top ends in about 15,000 miles. But it only had one speed in the hands of an 18 year old, including wheelstands off the stop lights regularly and being revved out to 8500rpm every Friday night trying to keep up with the Kawa 900s at the front of the pack. So it may not have been the bike's fault! Traded it in on a Harley Sportster in 1977 and still have that bike today. Agricultural enough to be resilient in the hands of the ham-fisted.

Edited By Hopper on 17/03/2023 12:20:39

Would it be any more complex or regulated than using a gas bottle on a barbecue or workshop blowtorch or camping stove. IE no regs other than pertaining to the gas bottle itself?

Those disposable gas torch bottles would seem to be about the right size for mounting in a loco tender etc and would get around having to make your own bottle and get it tested etc.

EDIT Or as Noel posted simultanously, one the small 4.7kg barbecue gas bottles in the larger locos.

And is coal going to disappear completely? It may be allowed for such small "heritage" applications. At a price of course!

Edited By Hopper on 17/03/2023 10:27:06

Edited By Hopper on 17/03/2023 10:28:40

In 1975, at the extremely knowledgeable age of about 18, I bought a brand new Triumph Trident 750cc three-cylinder motorbike. Being a typically smart 18 year old and now a third year apprentice I decided to do my own service after the first two free services by the dealer. This including adjusting the tappet clearances via the usual threaded adjusters on the ends of the rocker arms. These were located under a long narrow flat alloy cast rocker box cover secured by a small bolt at each end and two larger bolts in the middle.

Started the bike up to hear a loud clattering noise. OH OH! Must have set a tappet wrong. Took the rocker covers off and checked. All good. Nothing wrong. Put the covers back on. Started it up. Same result. OH DEAR. Must have stuffed something up. So, off with the rocker boxes. Nothing to see here. So off with the head. Nothing to see here. Off to the dealer to buy new gaskets and then I put it all back together a day or two later. Managed to snap one of the small rocker box studs by tightening it up to the same torque setting as the main head studs. Got it out, off to the dealer for a new stud. Reassembled a few more days later. Started it up. Same result. Clatter clatter clatter. WHAT THE ???

Good old Dad comes down the shed after hearing days of swearing emanating thence. I pull the rocker covers off. He takes one look at them and says "What's that mark there?", on the inside of the long flat rocker cover, right above the centre exhaust tapped adjuster screw.

I had only over-tightened the centre bolt in the cover, bowing the whole thing down far enough to contact the tappet adjuster on the end of the rocker arm. Hence loud clattering every time the tappet adjuster hit it. A five minute job to lay the cover on the concrete floor and belt it out flat with a soft hammer and restore the required bee's whisker of clearance. Reinstalled and hey presto! Clatter all gone. Doh!

But once I had broken the factory seal on those rocker box bases, cylinder head gasket and pushrod tube seals, I never ever could get them oil-tight for any length of time again.

Briggs and Stratton for one example. Nonetheless, you don't see the old sidevalve design referred to much in modern DIY literature. More likely to see reference to double overhead cam, which was the province of racing engines only in Geometer's day, ie post-WW2 but written by experts trained pre-WW2.

Those were the days, as they say, when the Owners Manual for a new motorbike came with instructions on how to while away an idyllic Sunday afternoon grinding the valves and decoking the piston top on one's new machine. These days, the owner's manual tells you not to drink the contents of the battery and to take it to a dealership for all service work.

If you Google Ball Turning Tool you will find a variety of attachments available for most lathes. Basically a tool bit mounted on an adjustable pivot and operated directly by a hand lever. They used to be a favourite DIY project of MEW types but these days are available cheap to buy from the usual suppliers. Many can be adjusted to turn large and small balls, or half balls, and concave as well as convex curves.

Not familiar with the Warco but if that three pulley set up is like most of them, that middle pulley should be mounted on a pivoting arm. So if you can move the motor a bit towards the centre pulley it should then be able to move enough toward the headstock spindle to roll the belt off the middle pulley as it is rotated. Then the middle pulley should be free to move toward the motor and allow belt removal. That's my theory, anyway.

Edited By Hopper on 16/03/2023 06:12:19

There is a lot of good info on M-Types at the Drummond Lathes group here **LINK**

Check out the FILES section in the group homepage. Lots of good stuff there, including the essential how to adjust the rather unusual headstock bearings.

Check the condition of the thread in your lower half-nut. There is a repair procedure involving making a threaded "bobbin", cutting it in half and soldering it into a recess machined in the old half nut lever. It is a bit involved so unless the old one is completely stripped, not worth the bother. A bit of backlash there does not affect its operation at all.

Edited By Hopper on 15/03/2023 22:58:03

At some point in the future at the editor's leisure, there will be an article in MEW on making your own quite simple resettable top and cross slide dials for the ML7. Absolutely worth their weight in gold. The best mod I have done on the ML7.

As for setting top slide and measuring lateral distances etc, I am big fan of the graduated carriage leadscrew handwheel. The drawback on the ML7 is disengaging the change gears to use the handwheel. So a lead screw dog clutch is in the works too, at some point when i get around to it. There was a handy design reprinted in MEW last month too, disengaging the gear on the end of the leadscrew which is good too.

Meanwhile, another way of doing it is set your topslide as best you can by lining up the machined straight front edge on it with the edge of the cross slide. Use the topslide to take the first roughing cut or two, but accurately up to the shoulder where you want it. Then take the finishing cut/s up to that shoulder using the carriage feed to ensure the diameter is parallel along the job.

I looked at drilling and reaming a dowel pin hole to keep the top slide set parallel when wanted but there is not a lot of meat there where it is easy to access so have not bothered.

I think you are on safe ground. No more racist than talking about old British motorbikes tend to leak oil more than Japanese ones. Just a fact of life. Country of origin is a bona fide factor in the equation and a legitimate topic for discussion. No reflection on the individuals or general populace of those countries, just on the manufactured products thereof.

Edited By Hopper on 14/03/2023 02:32:53

The link you posted appears to be the Starrett Store on Amazon. Presumably run by Starrett, or their UK agent on the Amazon platform?

Disappointing and not a good sign that it arrived damaged. Is this another great brand name peddling junk at the low end of their price range? Terribly disappointing if so.

Martin Cleeve's inexpensive book Screwcutting in the Lathe includes all the charts for cutting metric threads on an Imperial Myford, using the standard set of gears (20 to 75 in steps of 5, I think, plus the 38), using compound gearing. Accuracy is about one thou in 3 inches up to one thou in 8 inches. IE, more accurate than the lathe's mass produced leadscrew. He includes the BA gear charts too. And no need for oddball and expensive gears.

A very handy book, well worth buying.