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Line 4: <div id="level1"></div> == Level-1 induction == This is the most basic induction and provides only the absolute essentials. This is the most basic induction and provides only the absolute essentials. With the new card-based access control system coming soon then we may have a lot of people who suddenly need induction despite being already familiar with lathe work. That means this induction needs to be short enough we can do it quickly and in bulk cause we don't want people getting pissed off and skipping it or trying to bypass the control system. This plan for induction is fairly stable now and all trainers should be working from this plan, suggestions for improvements are still welcomed though! {\| class="wikitable" Line 11: \|- \| Proper Clothing \|\| * 'Workshop appropriate' clothing - you're going to get dirty and probably splashed with coolant etc * Sleeves tied back, no loose or flowing clothing, long hair tied back, risks of rings, proper footware. ▼ * No open-toed shoes or sandals. ▲* Sleeves tied back, no loose or flowing clothing, long hair tied back, risks of rings~~, proper footware~~. * Mention the catch points of the chuck and the 2 powerfeed screws. * Mention the main slide handle can catch things, mention loose clothing can catch the handwheels and upset work. Line 49 ⟶ 51: * Ceramics & Glass * GRP & Carbon Fibre * Hardened & chromed Steels (but see level 3) \|} Line 81 ⟶ 83: * Approximate truing and even tightening * The 3-jaw is not accurately concentric, so don't take workpiece out till you're finished * '''Not leaving the key in the chuck!''' This is the most common source of accidents on lathes and can cause serious injury \|\| Holding the work securely but only on a basic level for induction. Line 94 ⟶ 96: \|The Lamp \|\| * Positioning the mag-base lamp properly, taking care that it won't foul over the full range of motion intended. Beware of stroboscopic effects. * Main light doesn't work but if it gets fixed it will give non-stroboscopic light \|\| Getting a clear view, and not being fooled by strobe effect Line 190 ⟶ 191: \|Use of cutting fluids and other lubricants \|\| * Using the 3 types of cutting lubricant, the ~~spray~~liquid, the ~~liquid~~gel, and the ~~gel,~~flood and when each is used, Avoiding fling and mess using the gelled lubricant, using the ~~spray and~~ liquid when deeper penetration is needed to reach cutting faces. Use of proper lubricants for aluminium (the CT-90 is "Universal" and can be used) Using the flood coolant system~~, how it affects cutting speeds, avoiding spray, cleaning machine after use.~~ * Checking coolant level and topping up if needed, the warning light only reads accurately on start-up * How it affects cutting speeds * Avoiding spray * Cleaning machine after use. \|\| Proper cooling extends tool life, allows deeper faster cuts and helps keep machine clean Line 268 ⟶ 273: \|Tool Inspection \|\| * Checking the tools with ~~magnifying glass and~~ the inspection microscope ~~upstairs~~, what good and bad looks like on each of the 3 tool types. * Recognising wear and polishing on HSS tools and when it's OK and when the edge had been lost. * Looking for wear or more likely chipping on brazed carbide, the procedure for getting them re-ground if they need it. Line 455 ⟶ 460: \|General oiling \|\| * Which grade of oil to use ( ISO 68220 ) and where on the slideways the oil should be put. * Oiling the chuck but keeping the oil off the gripping surfaces, oiling the power-feed and leadscrew. * Leaving slides covered by the toolpost to reduce lube loss \|\|The more people helping with this the better \|- \|Refilling apron oil \|\|Checking the sight glass for level, where the fill and drain plugs are, using the proper grade of oil (ISO 68) and when to fill it up., how much to use \|\|With the one-shot in use this will need to be done often \|} Line 511 ⟶ 517: * Very large workpeices, faceplates and speed limits * Using fixed and travelling steadies for very long workpeices Why to use steadies How the 2 types grip and stabilise your work When to use Fixed Steady * Choosing location, have to make a flat to rest on * Installing * Tightening and lubricating * Keeping chips out with shields When to use travelling steady * Positioning Ahead - Stable but risk of transferring out-of-roundness and wearing brass blocks Co-incident - Strongest but hard to do and risk of chips getting dragged in Trailing - Roundness is stable but risk of longitudinal oscillations forming Burning in the brass blocks *** It's going to happen anyway, might as well make it happen when and where you choose * Using the dial indicator to maintain position on complex cuts * Calculating feeds&speeds for other materials not on the standard table Line 558 ⟶ 578: * Checking the workpeice hardness using the ultrasonic tester * Hard material turning is normally done without coolant * Swarf will come off HOT, depending on circumstances maybe up to red-hot * Rigidity of set-up it vital, pay special attention to stick-out and tool position relative to the slides ** Lock any slides you're not using * Examine the toolholder carefully when fitting a hard-turning insert, all parts must be in excellent condition or be replaced. * Hard turning requires relatively high spindle powers, be sure not to overload and stall the lathe Line 572 ⟶ 594: CBN Inserts are expensive and delicate, they must be treated with extreme care Maximum hardness ranges up to about 65HRC but values above 55HRC will cause rapid tool wear Swarf will come off '''~~RED~~up ~~HOT~~to 450C''' - take suitable safety precautions, consider how you're going to stop the machine if ~~red~~ burning-hot swarf is spraying over the controls Breaking a chip is unlikely, expect birds-nesting Depths of cut and feed rates should be low, ideally <0.1mm Surface speeds around 7550-~~150~~75 m/min, the harder the material the slower the cut but go as fast as possible for any given job, CNC machines can run faster than this but our set-up won't allow it. * Diamond tooling exists for use in hard non-ferrous materials and highly abrasive materials * Advanced tooling that exists but we don't have. I.E. CBN/Diamond (We don't carry this tooling but if inductee provides them this module can be run) ** Diamond tooling comes in PolyCrystaline Diamond (PCD) which is very expensive - more so than CBN, and MonoCrystaline Diamond (MCD) which is eye-wateringly expensive. PCD is very, very hard, MCD is the hardest tooling material known to exist. Diamond tooling cannot be used on ferrous metals as the carbon from the diamond will dissolve into the iron Diamond can be used to turn exotic materials such as aluminium superalloys, nickle superalloys, precious metals, tungsten carbide and carbon fiber Maximum work hardness for diamond tools can go as high as 70HRC although wear increases above 60HRC Cutting speeds can range up as high as 1000m/min or as low as 10m/min depending on the hardness of the work ** Depths of cut and feed rates should be low, ideally <0.1mm, however the very high surface speeds used with PCD tooling will still result in rapid material removal rates * Workholding using all chuck types and recovering concentricity * Using reamers * Turning between centres Why you might do it * Improved concentrically and repeatability * Holding awkward shapes * Reusing centers on existing parts or that someone else cut ** Recutting a center if you need to (toolpost support trick) Setting up a center and a catch plate * Installing a center in the headstock * Installing the catch plate * Picking a suitable dog size, setting it up so it won't slap Caution about over or undertightening * Alternatively making a center on stock held in a 3/4 jaw chuck * Live or Dead center at the tailstock? * Might require the use of steadies if the part is long Turning between centers * The dog and catch plate will cause imbalance so watch speed * Parts may be very long so watch out for flex Use support if needed Take shallow cuts Tailstock offset turning * Regular centers only for the smallest of offsets * Using ball-bearing centers▼ ** Part distortion if used too much ▲* Using ball-bearing centers for larger offsets ~~<div id="level4"></div>~~ *** Resetting the tailstock alignment when done, high precision required * Making and shaping brazed carbide cutters ~~== Level 4 induction ==~~ ~~We welcome suggestions for what should be covered in an advanced course if we're able to run one~~ == Maintenance == Line 605 ⟶ 651: \| Checking oil tanks and draining/refilling \|\| Location of the sight-glasses, fill point and drain points for all 3 oil tanks, which grade of oil goes in which and how much. Main tank takes 1L of ISO68, screwcutting gearbox takes 0.5L of ISO220, Apron takes 0.3L of ISO68. Disposal of used oil ( How do we handle this? ) \|- \| Oiling points \|\| Applying oil using the ~~small~~high ~~red~~pressure oil can to all the oiling points listed in the manual, including the ones under the changegear case \|- \| Oiling the changegears \|\| Opening the case, oiling them, do not bypass safety to run the gears while oiling