Member postings for mgnbuk

That looks like the Warco equivalent of the Clarke CL500M lathe, for which the manual can be downloaded here

Page 17 discusses changing & tensioning the spindle drive belts.

HTH

Nigel B

A 0.001mm dial indicates high sensitivity, not that the instrument performs just as well as a micrometer! I've never used a DTI to measure anything. Am I wrong?

I still have the Mitutoyo 0.001m resolution dial gauge that I used to use for demonstrating to customers that alignments were within spec. on rebuilt machine tools. For its intended use, it was regularly sent out to an independant test establishment & came back with a certificate that detailed the errors thoughout its working envelope (1 mm in this case) - it read within 0.001mm over the full travel with an uncertainty of measurement of +/- 0.001mm, so either dead on or 0.002mm error over 1mm. Having sat in a cabinet in my garage for around 20 years, it is out of calibaration at the moment.

The readings taken with this gauge were used to measure the machine alignments when compared to precision artifacts i.e. large lumps of calibrated granite. So there are instances where a direct measurement is useful. Obviously care had to be taken to ensure that the gauge was set perpendicular to the artifact, but when looking for small errors, care has to be taken period !

I do note that Dave's comment refers to DTI rather than dial gauge, but Neil's comments were WRT plunger clocks. DTIs can be accurate, but IIRC they only read "correctly" when the stylus is in certain positions relative to the body. I have a recollection of a DTI coming with an instruction leaflet that showed the effect that having the stylus set at an angle would have on absolute readings - not an issue if looking to adjust the setting of something to show zero deflection.

Nigel B.

As for costs, don't know. Probably not that expensive as its a common enough process these days.

The machine tool rebuild / retrofit company I used to work for used the grind / hard chrome / grind to size method to sort out worn ailstock barrels & worn bearing seats on spindles. The parts were larger than model engineering friendly machinery, but 20 years ago the costs were significant & the process slow - an initial grind to remove wear and impart a very good finish to the part before sending out to the platers for the actual plating, then return to the grinder to finish grind. One issue that frequently occurred was the plating not adhering to the component, something that did not reveal itself until the finish grinding operation when the plating would flake off. This required the entire surface to be ground back to the parent metal & then replating. On one component (a Crawford Swift spindle with worn bearing seats) this happened four times before the part was completed - a process that took several weeks.

The last part I had repaired this way was the tailstock barrel on a CNC lathe that the operator crashed the tool turret into at rapid traverse This bent the 100 mm diameter barrel by 0.05mm - not a lot, but enough to sieze it in the housing. This was ground on the OD to remove the bend, plated oversize, ground back to original size and the 5MT taper reground true to the OD - IIRC this cost £400 + Vat around 10 years ago.

We used to use a company in LIversedge, West Yorks - Brian Kemp Grinders - for this type of work & usually sent both the component to be plated + the component it ran in to them. They honed the bore & ground the plated part to give the required fit. Brian passed away many years ago, but his wife continued to run the company. They still have a current website.

I suspect that Taf's solution will be a lot cheaper + produces a full length bore..

Nigel B.

Over 2 1/2 years since Steven Van der Watt posted the last update above, which was also his last post.

A lot has happened since then, so an update may not be forthcoming.

Nigel B.

Continuing to stir the pot, does anyone think this is an industrial tool? They're widely used in manufacturing...

I don't think so - doesn't appear to be well-used enough to be an industrial teaspoon. More like a domestic market item IMO.

Nigel B

No-one doubts Myfords were used in industrial settings, but they are not, repeat not, designed for production work. By production work, I mean lathes performing the same operation thousands of times per shift, usually on a production line.

In your opinion, Dave.

Seems strange that Myford made capstan attachments then. Bed and cross-slide units + cut-off slide, multi-stop unit & lever tailstock all still in the price list in 1992, though I can't see those items being of much interest to most model engineers. These items come up on Ebay quite often, so someone must have used them.

Mind you the con rod reboring fixture had disappeared from the price list by then - another item that probably didn't sell well to model engineers, though that would probably have been a sought after attachment at one point in time for motor garages.

I mentioned before that one of my former employers customers had several ML-7Rs used in the production of taps and dies in the mid '90s. If half a dozen ML-7Rs operated by ladies can produce the parts you make, in the quantities you want to make them, at a price (and level of investment) that keeps the accountants happy, why would you want a different (probably more expensive) solution ? Not all manufacturing is large parts, and not all batch sizes demand mass production specific machinery.

A Myford brochure about buying a used machines (and selling their rebuilding services) says in the intro that, at their peak, Myford was producing 500 lathes a month - I rather doubt that the bulk of them were going to hobby users.

Nigel B.

This sounds like the problem on all round column mills. You have to take very light cuts or work at right angles to the bed.

Page 34 of the manual Thor linked to shows that there is a full length key mounted to the column that constrains the head casting, which has an "adjusting gib" and a "clamping gib". Difficult to see how the head could swivel on the column with that arrangement, so is the column rotating in the base due to inadequate clamping here ?

Nigel B.

This sounds like the problem on all round column mills. You have to take very light cuts or work at right angles to the bed.

Page 34 of the manual Thor linked to shows that there is a full length key mounted to the column that constrains the head casting, which has an "adjusting gib" and a "clamping gib". Difficult to see how the head could swivel on the column with that arrangement, so is the column rotating in the base due to inadequate clamping here ?

Nigel B.

Watching TouTube mini lathe improvement videos (amongst others) while recovering from recent hand surgery - preferable to day-time TV ! - has motivated me to do some "upgrades" to a Chester Conquest. I got this (complete mechanically but no electrics other than the motor) from a Chester open day many years ago with a view to using it a a basis for a CNC conversion, but have decided to use it as-is with some of the "improvements" detailed on the likes of "We can do that better" , "Artisan Makes" , "Hammerland" and others.

My modified thumb is sort-of working again, so parts have been ordered & started to arrive - taper roller bearings, steel headstock gears, aluminium timing belt pulleys & some electrical components so far. Modified cross & compound slide gibs, saddle keep strips, feed screw thrust bearings & some form of rigid base (I am thinking of using a 50mm thick pressed concrete paving slab) are all on the "to do" list. Also have ideas to replace the permenant magnet DC motor (not a great solution for this application IMO) with a multi-step pulley & AC motor arrangement to get more torque at lower speeds than the DC arrangement can provide - but that is a way off.

I'm under no illusions that this will produce a "Myford or Boxford beater", but I spent a large part of my working life modifying and upgrading machine tools & would prefer to play along those lines now I have retired, rather than get involved with more traditional model engineering subjects. Well to start with anyway.

I can't say I am surprised that a 40kg-ish small lathe not bolted to a rigid base shows signs of deflection at low force inputs & improves noticably with a foundation - full size machine tools do so also & the manufacturers recommendation for all I have been involved with is to bolt them to a substantial concrete foundation. Some need this more than others, being little more than a hard facing that get most of their rigidity from the foundations (Binns & Berry lathes & Butler Elagmills come to mind here) & others (like Asquith gantry machining centres) rely upon the foundations to hold several separate machine elements in the correct location relative to each other - there is no machine without the foundation.

Nigel B.

Nigel B.

What machine are you refering to ? Knowing the machine would give more targetted replies.

Your initial query was for a lubricant for sliding surfaces, but now there is mention of "refreshing three oil baths" ?

Many machine tool gearboxes use hydraulic oils - 32 or 46 viscosity mostly. These should be obtainable from agricultural suppliers as well as industrial suppliers. Slideways are best lubricated with slideway oils, typically 68 viscosity, though I have come across machines that pass hydraulic oil from a gearbox to lubricate the slideways. Using an oil with a higher viscosity than recommended may lead to diminished performance from the machine - absorbing more power to turn gearboxes, for example.

If toxicity is particularly important to you, then AFAIK there are "food grade" hydraulic oils available. I don't have any recollection that hydraulic or slideway oils are are any more or any less toxic than other lubricating oils & didn't take any special precautions when using either type for work.

160 visocity oil would be way too thick for the size of lathe used in most home workshops. At my last employment we had only one milling machine that specified 160 slideway oil & that had a 10 tonne table loading !

"WD" products are great for displacing moisture & applying a light rust preventative layer - they are not serious lubricants.

Nigel B.

Is there a good way of calibrating one's filament, and a good test piece to use to refine the settings?

Have a search online for a "temperature tower". There are several on Thingiverse - I can't recall exactly which one I use as my computer crashed since I downloaded it. The file is resident on my printer SD card, so I have not had a need to find it again.

This short program builds a tower comprising 2 blocks a short distance apart with an unsupported bridge between them. Each level prints at an increasing temperature (IIRC 5 degree increments from 180 to 225 C). For easy reference, the temperature each layer printed at is embossed in one of the blocks. When cooled, inspect the tower for the layer that looks to have printed the best. Run this program whenever you change to a fresh reel of filament to see how the new stuff works compared to the reel just run off - IIRC mine takes around 45 minutes & doesn't use much filament.

I am currently running Anycubics own brand PLA at 205 C extrusion temp on a 60 C bed. Bed grip on Anycubic's textured surface is tenacious until it has fully cooled, when the part just lifts off. Minimal stringing & good layer adhesion.

I have been using Gyroid infill recently - some suggestions online (through testing) that this has the best strength in all axes. Latest Cura version is 5.2.2

Nigel B.

I have an English "handbook" for my FV-320T clone of the FB2

I don't know how well it would copy, as it appears to be based on a poor photocopy of the original Emco manual with the Emco logos "redacted" & a basic English text added in place of the German. Of the 14 A4 pages, only 6 are instructional, the rest being exploded parts diagrams.

There are no great pearls of wisdom contained in the sparse text accompanying the diagrams & there is less content overall than the German text manual available to download here.

Google Translate does a pretty good job but, unfortunately, I don't seem to be able to copy text directly from the German .pdf manual & appreciate that typing passages in long-hand is a PITA

From a servicing POV these are pretty basic manual machines - what in particular are you looking for guidance on ?

Nigel B.

There is an English manual on John F's link, but you need to join the group to be able to download it. First English manual I have seen for the FB2 - thanks John !

Richard - drop me a personal message with your e-mail address & I'll send you copy of the English 'pdf I just downloaded.

Edited By mgnbuk on 28/02/2023 13:33:14

Edited By mgnbuk on 28/02/2023 13:35:05

Not a great picture, but hopefully you can make out the recess for the PTFE tube in the top of the heatbreak & see that the hole through the heatbreak & the entrance to the nozzle is only big enough for the filament - no room for an internal PTFE guide to bridge the gap.

Ebay is my go-to source for items like small fans. The fans are sized by their outer (square) case dimensions & operating voltage. 40mm square 12V fans start at £2.29 posted.

Nigel B.

Journeyman's sketch didn't ring true for my Mega, so I dug out my spares to check and it is different to that shown.

The sketch does not show theAnycubic heatbreak arrangement correctly - on the Anycubic print head the PTFE tube fits into a recess at the top of the heatbreak & the filament path through the heatbreak to the nozzle is not via a section of PTFE tube. The heatbreak screws into the top of the heater block part way & nozzle screws into the underside of the heatblock as the sketch shows. The amount of insertion of the heatbreak has to be such that the nozzle firmly abuts the end of the heatbreak within the heater block when it is tightened - it is this abutment that makes the seal - there is no PTFE tube section between the heatbreak and the nozzle. Final tightening has to be made at operating temperature !

Anycubic have a basic video covering nozzle replacement here.

I don't think the Mega series printers are that old - IIRC I bought mine around 3 years ago and they were still available until quite recently. The operater interface appears to be their own and it is what it is. While it would be nice to have a few "bells and whistles" such as the abilty to easily add features like auto bed levelling sensors, mine has required little intervetion after a bit of initial fiddling to get it set up.

Nigel B.

Z-height adjustment will definitely be in software and available from a menu.

I don't recall such a software adjustment in the menus on my Anycubic Mega & the factory instructions only refer to using the heated bed levelling screws for setting the initial clearances / nozzle height. I also had to tweak the Z axis reference switch actuating screws to get the cross rail to reference parallel to the heated bed surface.

Could you provide a link to show where the software seting may be ?

Nigel B.

Myford would appear to disagree with your assesment of their customer base, Dave - the opening paragraph for the Super 7 brochure reads :

"Established thorughout the world as a symbol of precision & performance, the Lathes of the Myford Series 7 range are used in production, repair and maintenance workshops, technical schools, scientific laboratories, also by serious model makers and hobbyists".

Note "serious model makers and hobbyists" being the last stated audience. Even a "cheap" Myford would have been a serious investment by most "normal" people's standpoint in the '50 & '60s, so I would not expect that that market was large. Strangely I felt that I had gained in capability (if not in capacity) when I swapped my Boxford CUD for a Super 7, but each to their own !

Hopefully the OP will get many years of enjoyment from his new aquisition.

Nigel B.

I managed to get my 3D printed Dremel holder on to the lathe & succesfully reground the 3 jaw SC chuck jaws.

My initial design of Dremel holder fit the Dickson toolpost securely, but I hadn't got to grips with the "Thread design workbench" in Freecad to accurately model the thread for the Dremel nose - variously described as M19x2 or 3/4"-12. M19x2 taps are rare and expensive & the only standard 3/4"-12 thread seems to be 3/4" BSF. Zoro put up a new 3/4" BSF tap for less than most used ones were being listed at on Ebay & the M18x2 hole I had modelled opened out easily with the new tap held in the chuck & the holder mounted on the toolpost. The Dremel screwed into the resultant hole nicely. Turns out I should have allowed a couple of millimetres more for the Dremel body to clear the toolpost as it interferes slightly, but it does just fit.

I didn't make up a grinding jig a-la-Hopper, but chose the "centrifugal force" method of running the lathe spindle at maximum speed (2200 rpm on the Super 7 IIRC) to hold the jaws against the scroll. Top slide set at round 10 degrees to give fine outfeed capability & I proceeded slowly to lightly touch the clamping face of the jaws, which had been marked up with a marker pen to judge progress. I had treated the chuck to a strip down & clean last week before starting the regrind.

It was apparent straight away that only 2 jaws were being ground initially, but after several light passes all were cleaned up. The small marks visible in the "light" jaw show the remains of the original surface.

This has made an improvement to runout. Checks carried out on a length of 25mm silver steel using a 0.1mm resolution dial gauge showed 0.08mm TIR close to the jaws and 0.13mm around 100 mm out before the grind improved to 0.03 mm TIR and 0.08mm respectively afterwards - a worthwhile improvement, I think & not bad for a 60-ish year old chuck.

I'll have another try at the 3D printed mount, both to give a bit more clearance to the Dremel & get to grips with the thread before moving on to the main reason I wanted a toolpost grinder in the first place - sorting out a Soba brand (short for "SO BAd" ? ) direct spindle nose mounting ER25 collet chuck that I made the mistake of buying at an ME Ex. It was sometime after the purchase that I found it wouldn't screw onto the spindle nose, which took at lot of lapping using a 2MT Myford nose adapter to get it to fit the spindle only to find that the ER taper runout was so far out as to make the item useless. A regrind of the collet seating taper with the chuck mounted on the spindle should (hopefully) make the thing useful.

Nigel B.

they are not industrial production machines, that is not what they were designed for.

One of my former customers would disagree with that assertion - they had several ML-7Rs operated by women used in the production of taps & dies. Another started his business in his shed with a Super 7 and grew substantially from there, and it was quite common to find a Super7 or ML7 in tool rooms in large enterprises.

I would hazard a guess that light industrial, tool rooms, repair workshops & education was exactly what the Myfords were designed for - that they happened to be suitable for hobby users & that their "designed for mass production using the methods of the time" made the costs pallatable for that market was a happy coincidence.

I guess that when Myfords became dependant upon model engineers was when they decided to call it a day.

Nigel B.

You must be very lucky, inhalation of fine carbon particles can inflict serious damage to your lungs leading to COPD, leading to a shorter lfe.

Never saw anyone wear a mask when machining CI anywhere that I worked. The machine shop at Broadbents was covered in fine CI dust & one of my holiday shutdown jobs was to clean all the fluorescent lamp fittings for accumulations of talcum-powder fine CI dust. No special protection advised or provided for what was a filthy job & no long term ill effects.

The last 16+ years I worked in a graphite machine shop. While there was dust extraction, there was still fine graphite dust pretty well everywhere. Dirty hankerchiefs normal & you got grubby, but no long term effects. My employer had had an HSE inspection where they took dust samples & did extensive tests, but came back with no special recommendations as they found no special health hazards, explosion risks etc.

I don't belive that it is good to breath fine dusts of any persuasion, but have not seen anywhere that CI dust poses a particularly serious risk ?

Nigel B.

and anyone without internet access......

...... in 2023 is at a definate disadvantage !

Nigel B.