tools:lathe

Hafco Metalmaster AL-50GA Metal Lathe

al-50ga.jpg The metal lathe is the first tool purchased by communal funds at the Artifactory. Members are responsible for providing tooling and safety equipment for use with the lathe, there is currently a small selection of communal tooling with the lathe but regular users will want to acquire their own tooling.

The lathe is a very dangerous tool and is not to be used until you have had a safety induction and basic training by someone on the lathe trainers list below. This is true even if you have used lathes before and is non-negotiable.

Ben Connor

Steve
Ben Connor
Kamil
Narelle
Dave Madgewick
Spondy

Work within your capabilities and knowledge, and the machine’s capabilities. If in doubt, ask.

1. Don’t hurt yourself

• Long hair to be tied back. No loose clothing or jewellery
• Work to be rigidly mounted in the chuck or on the faceplate
• Tools / toolpost (and tailstock if in use) to be tight
• Operating the lathe requires the operator’s full attention. Minimise distractions and stop work if necessary
• Wear appropriate PPE. This includes eye protection and may include ear protection. The PPE light in the machine room should be activated when the lathe is in use.
• Do not turn materials that are hazardous when inhaled. If in doubt, consult the relevant MSDS.
• Don’t try to clear swarf with your hands. That stuff is sharp!
• Work with the chuck guard down
• Don’t leave the chuck key in the chuck
• Don’t spin the lathe with the chuck jaws un-tensioned.
• Unplug the lathe when changing speeds or any time the headstock guard is open
• Mind fingers with belts / pulleys when changing speeds
• Note that the chuck is screwed onto the spindle. Therefore, do not run the lathe in reverse without a good reason, and if you do, be careful.

2. Don’t hurt the lathe

• Keep the tool clear of the chuck
• Be very careful with power feeding, especially near the chuck
• Don’t run the lathe with the clutch disengaged, as this is likely to damage the belt
• Be conservative initially in your choice of feed rate and depth of cut. Work your way up.
• If you stall the lathe, back the tool out immediately. If it doesn’t start moving again do not spin it by hand. Hit the e-stop and start again.
• Use appropriate tooling for the job you are doing
• The metal lathe is only for use on metals or plastics. For hard materials (e.g. titanium or hardened steel) users must provide their own tooling.

3. Be a considerate tool user

• Clean up after yourself. Vacuum or sweep up swarf, including from on the floor
• Put away lathe tools / tooling you have finished with. Return anything you have borrowed from the general area
• Don’t remove lathe-specific tools from the machine room
• If you change chucks, ensure the chuck is done up tight on the spindle and the locking tab is tight.
• Chuck jaws for the 3-jaw chuck are a set. Do not mix them up with other sets.
• When changing jaws in the 3-jaw chuck, insert jaws in the correct order. If you don’t know what this means, ask: don’t try to change the jaws.
• Place damaged / worn out tooling in the receptacle provided.
• Notify #tools_and_fabrication on Slack of any problems.

4. Get good results (highly simplified!)

• Make sure your tool is at the correct height, i.e. at the centreline of the lathe
• Respect the limits of the machine – high speed means low torque and vice versa
• Lathes work best when making a decent-sized chip. It is possible to get a lousy cut by being too timid
• Understand the basic lathe operations – turning, facing, drilling, boring, parting off – and develop a strategy for your piece before you start
• Keep your work rigid. Minimise the amount sticking out of the chuck, and use the tail stock to support the work if possible.
• Remember everything bends under cutting forces. For precise work, take a final ‘finishing cut’. Measure as you go – don’t rely on the markings on the slides.
• Consider doing some research on cutting speeds, tool selection and tool geometry, as this is too large a topic to effectively summarise.

Reading this list is not a substitute for being trained.

The lathe takes 12mm tools. It has a quick-change toolpost to facilitate easy changing of tools and setting of tool height.

The Artifactory has a small selection of tooling sufficient for basic turning operations. However, long-term users may want to acquire their own tooling. There are a number of brazed-carbide tools of various kinds, but these are of generally poor quality and perform very badly on anything except soft materials. There is also a selection of tungsten carbide insert tooling, which works better most of the time.

Bar stock can be obtained in short lengths on the internet (ebay). However this is a relatively expensive way to buy it.

Local suppliers include:

  • For steel, Di Candilio Steel City have a wide range of sizes of CS1030 from 10mm dia up. CS1030 is a cold-drawn medium-strength steel that is highly machinable (without being strictly a 'free machining' grade). It's also relatively cheap: 20mm bar is $80 + GST for a full 6m length at the time of writing. Di Candilio will cut to any length you want for a small additional cutting charge.
  • Robert Cameron and Co have a variety of non-ferrous metals (e.g. brass and aluminium) and will cut to length. They don't really have any meaningful web presence at the time of writing but they respond to e-mails and answer the phone. Pricing as at mid-2020 is shown below.
  • Austral Wright seems to be the ultimate wholesale source of brass in WA. Their pricing is ~25/kg, which is not much more than half what you pay from ebay, excluding shipping. That translates as $93 for a 3.6m length of 1/2“ brass. The rub though is that up to ~25mm they only sell in full lengths. For larger sizes (say 50mm) they sell in 500mm increments.

The Blondihacks Lathe Skills series on Youtube is a great place to learn about working on a small lathe.

Tool Height 12mm
Distance Between Centres 500mm
Swing Over Bed 230mm
Swing Over Cross-Slide 130mm
Centre Height 115mm
Spindle Bore 20mm
Spindle Nose Type Threaded
Bed Width 115mm
Headstock Taper 3MT
Tailstock Taper 2MT
Cross-Slide Travel 115mm
Compound Slide Travel 50mm
Longitudinal Feed Range (Z Axis) 0.1 - 0.2 mm/rev
Metric Thread Steps & TPI Range 11 (0.5 - 3 mm)
Imperial Thread Steps & TPI Range 27 (8 - 56 tpi)
3 Jaw Chuck Diameter 100mm
4 Jaw Chuck Diameter 190mm
Spindle Speed Steps & RPM Range 6 (100 - 1800 rpm)

Replacement drive belts (the thin one that snaps from time to time) can be had from Machinery House for $31. It's a GATES 5M710 poly V-belt

Lots of useful info at http://bedair.org/9x20camlock/9x20project.html

The lathe appreciates some lubrication, but try to keep the oil off the belts!

  • tools/lathe.txt
  • Last modified: 2021/07/26 20:05
  • by ben