Lathe arriving – source some practice materials

[starjumpParticipant @starjump]

Hello,

I am buying a second hand lathe and will need some practice material. Are there sources that you’d recommend please.

I’ve two Hemingway kits, simple ones that will be my first projects. However, practice stock has to be useful for checking technique, mounting set-ups, tool selection etc – I guess?

And so what would you buy for a start-up selection please?

With thanks, Starjump.

[JasonBModerator @jasonb]

M-Machine have a good range. For steel get EN1A or EN1Apb, Stainless grade 303 and aluminium 6082 (HE30) as they ar eall free cutting.

 

machine-metals.co.uk/downloads/Metals catalogue.pdf

[Dave HalfordParticipant @davehalford22513]

Nothing steel from B&Q metals stock.

EN3 will disappoint you unless the cutting tool is very sharp.

Old ball cock levers are good for 6mm / 1/4″ brass rod if it’s not been bent.

If you live near either Redditch or Coventry Rapid Metals keep cheap off cuts at the counter.

[Howard LewisParticipant @howardlewis46836]

You might be able to cadge some off cuts from your local steel stockholder, for the price of a contribution to the tea fund!

Just practice turning them down to become familiar with the machine, tool grinding – if HSS, and cutting metal. Getting to know what speeds and fees to use will stand you in good stead.

Make your mistakes on relatively cheap metal, rather than material from a kit. There will be very little excess material in a kit!

Haste can be expensive

If you take a chance on what the material is, you could get a bit of mild steel from the local scrapyard.

A Quorn is unlikely to be a suitable early project. Stick to simple things until you have more experience.

As you are reducing the diameter of a bit of mild steel, you will be gaining experience of what speeds and feeds, and possibly tool angle will be best.

For a first project, I would suggest a Centre Height Gauge. You will gain a little experience of turning facing, drilling and tapping, and end up with a tool that you will probably use every time that you regrind, or change a tool.

Howard

[Mike HurleyParticipant @mikehurley60381]

Don’t get too upright about materials in the early days. While the previous replies are perfectly valid, sometimes working your way through an unknown assortment of (primarily) steels is a very useful learning exercise for newcomers (and a lot cheaper these days). When I first started out I simply couldn’t afford to buy pucca materials, just odd bits found around and about.

It helps you to learn how to identify core issues and stop to THINK –  Is it my technique? Tool type? Speed/feed? Etc. However, when doing a ‘proper’ project, yes take advice and use the best, identified materials where you can.

Just my humble opinion based on many years experience.

Note: Howard beat me to it in some respects!

[jon hill 3Participant @jonhill3]

 

You could try your local metal fabricator and ask if you can buy / donate to the tea fund for raiding their scrap bin.

 

Find out where they get their metal from and only select colour coded steel or labelled metals so you can work out what you have picked up.  Most metal dealers hace colour codes on extrusions and sheet / slabe.

If you know their metal merchant you can obtain a free brochure or booklet to identify what you have.

Scrapyards can be good if you can identify the metal, again colour coded or clearly labeled offcuts.  Watch out for laser or other heat cut metal, this will form a hard unmachinable skin, however a metal bandsaw or chopsaw will remove this if you take say 5-6mm off the edge.

If you turn up in a hard hat, boots and high vise the scrapyard chargehand might be more amenable to allow you to wonder round.

 

Best of luck

Jon

[old martParticipant @oldmart]

I recommend that you start with aluminium, a scrapyard may have some short offcuts about 20-40mm diameter. The cutting tool top edge should be set or shimmed to as close to centre height, easily judged by the height of a centre in the tailstock. A very small amount of lubricant such as WD40 or oil will be required for use with aluminium to prevent it sticking to the cutting edge.

There are several books on the subject which members will be able to recommend to help get you started.

[Roderick JenkinsParticipant @roderickjenkins93242]

I would do as Jason recommends.  Fabricators tend to have sheet and angle that is good for welding-not necessarily good for turning.  I have been pleased with the materials I have purchased from Metal Bar Ends on ebay but there are other ebay sellers who are worth a search.

Metal Bar Ends

Rod

[HollowpointParticipant @hollowpoint]

I use Macc models for most of my materials.

I am reluctant to use scrap nowadays, the unknown grades can cause all sorts of problems. There’s nothing worse in my opinion than being excited for a new project or idea and then that bit of scrap you thought would be ideal is actually as hard as all hell and completely unusable.

As said, stick with EN1A. It really isn’t all that expensive. Especially rounds in the smaller sizes. Its a pleasure to machine and once you have learnt how it behaves you can just keep on ordering the same.

[PeteParticipant @pete41194]

There’s usually lots of short plastic round stock on places like Ebay etc. For an entry level person, getting used to the lathe and controls well enough first is more important than what material you might be practicing with. And generally most of the machinable plastics will be easy on your cutting tools. It’s also a good material to practice single point threading.

It’s also not if, but only how long before you make a mistake and touch the chuck while it’s under power, usually with the top / compound slide. I can warn you, but almost for sure you’ll still do it by mistake. It’s best to then remember what not to do from those.

[old martParticipant @oldmart]

Plastic bar stock as Pete mentions is an excellent practice material, even a serious mistake will not damage the machinery. One of the nylon types or PVC would do.

Tell us more about the lathe you have bought.

[Nigel Graham 2Participant @nigelgraham2]

Plastics can be right so-and-sos to machine though. Some, including ‘Nylon’, are certainly machineable but produce long strings of swarf that can wrap round everything and obscure the progress of the cut.

Dave Halford recommends avoiding the steel rod sold by B&Q and the like. It’s not free-cutting, and often of questionable surface and dimensional quality. It’s fine for buildings components, garden gate parts and the like. It is not intended for precision engineering components. I have used some in model-engineering where its limitations were allowable and the prototype components may have been forged wrought-iron; but it was awful stuff to turn and thread.

Colour codes on bar ends are not infallible. There is no industry-wide standard and the colours tend to be specific to manufacturer.

[Mike Hurley]

On Mike Hurley Said:

Don’t get too upright about materials in the early days. While the previous replies are perfectly valid, sometimes working your way through an unknown assortment of (primarily) steels is a very useful learning exercise for newcomers (and a lot cheaper these days). When I first started out I simply couldn’t afford to buy pucca materials, just odd bits found around and about.

It helps you to learn how to identify core issues and stop to THINK –  Is it my technique? Tool type? Speed/feed? Etc. However, when doing a ‘proper’ project, yes take advice and use the best, identified materials where you can.

Just my humble opinion based on many years experience.

Note: Howard beat me to it in some respects!

Sorry mate but you’re plain wrong here.  This is terrible advice for a beginner.

The early days are precisely when you need to be uptight about material selection.

A beginner using random mystery metal will be bombarded with unanswerable questions.  Is it my speeds or feeds? Am I taking too big a DOC?  Is my DOC too shallow?  Is it the tool I’m using? Is it my workholding setup? Is there a problem with my lathe?

Because that beginner cannot know the properties of the material they’re cutting, there’s no answer to “What the hell is going wrong here?”

Free cutting low carbon steel (EN1A or EN1A Pb), free cutting brass (CZ121, IIRC), and free cutting aluminium (6082) are absolutely what any beginner should start with.

That way they’ll be giving themselves the best chance of learning without frustration.

[Howard LewisParticipant @howardlewis46836]

Increasing the DOC is part of the learning process, to find out when too much is too much, either for the tool, or the machine

The same is true of speds and feeds.

An unknown material might be difficult to machine, but that is how you learn how to deal with difficult materials. You will come across them eventually.

(Try turning rebar! Not a nice material, but it can be done).

Just change one factor at a time, otherwise you won’t know what improved matters, or made them worse. In that way you learn.

My turning instructor, who had made his living on piece work, tolerated us taking very light cuts until we gained the confidence, and the skill in tool grinding. In the first weeks we were taking 0.010″ cuts. At the end of the year, we weren’t frightened by 3/8″ cuts!

Howard

[Mark EasingwoodParticipant @markeasingwood33578]

I have found the following to be reliable, amongst others, Macc Models (who also have an Ebay shop), M-Machine, Noggin End Metals, Rapid metals and streamlinemetals on Ebay.

[starjumpParticipant @starjump]

Hello Everyone, A massive thank you. You all make thought provoking points. So many kindly answered that some advice was repeated to an extent that it made a real impact.

Experience and recommendations mean there are a good few retailers I could safely go with. After a quick look at some of the web sites, I have decided that Mac Models is user friendly enough for material selection for me as a starting point.

This quote from @southernchap seemed to echo many’s thoughts: “Free cutting low carbon steel (EN1A or EN1A Pb), free cutting brass (CZ121, IIRC), and free cutting aluminium (6082) are absolutely what any beginner should start with.”

I’ll order some of this, any thoughts about rounds vs hex or other shapes? Thank you in advance.

Starjump

[BazyleParticipant @bazyle]

Round of course – that’s what lathes do. If you were taking about a milling machine then some square might be in order. Hex would just waste material as you turned it to round.

[starjumpParticipant @starjump]

Ok!  🙂

Thank you

[JasonBModerator @jasonb]

Though if taking the advice of some here to make simple tools square and hex would be useful. For a start square will let you learn how to set work to run true in a 4-jaw. Hex can make nuts and bolts so turning to a shoulder and threading can make something more useful than a round headed bolt.

This may make the old blokes fall over but these days metric size material is often cheaper than imperial. Also if you can commit to it quantity is often a lot cheaper. For example M-machine want £3 per 300mm but someone like Ringwood who I also use want £15 for 3m which is half the price but sometimes it’s better to get form M-machine if you want several different items as it’s one postage cost.

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