Milling machine tooling

[Jeremy Smith 2Participant @jeremysmith2]

I purchased an rf30 mill about 6 months ago, and got some cheap chinese bits off of amazon to practice on. I have only one 3/8” collet currently (the morse taper 3 one). I have broken every bit as of now, and am ready to commit on new quality bits, now that I finally know what I am doing

What sizes should i purchase to get started? There is a guy in the classifieds getting rid of a ton of machine shop tooling and bits, so I have a unique opportunity here to get a bundles worth. It’s time to outfit the mill.

[Jeremy Smith 2Participant @jeremysmith2]

Milling machine tools

[Pete.Participant @pete-2]

Do you have a tool a cutter grinder to sharpen all those used cutters?

Might as well buy 3mm to 12mm in mm increments, they're not expensive, if you've broken every single one you've used, might be worth watching lots of free videos on YouTube, plenty of videos showing the basics, enough to to get you past breaking everything you use.

[noel shelleyParticipant @noelshelley55608]

The first thing is to decide what system of holding you are going to use. Clarkson autolok style, in which case you will may be need both metric and imperial collets. Or metric ER collets which will cover both imp and metric sizes or some other type ? Second hand cutters will be be useless unless their sharp. Getting them reground may well prove exspensive. Learning with blunt cutters is a hiding to nowhere. Noel

[Thor 🇳🇴Participant @thor]

Hi Jeremy,

I assume you already have a milling vice and clamping kit for your milling machine. As Pete says, buy some more collets or a collet chuck, I use ER collets since I can use them both on the milling machine and on the lathe to hold round work. The collet sizes I use most are from 3mm to 16mm. The sizes you need depends on what kind of work you do. Harold Hall's website has a section about grinding, cutters must be sharp.

Thor

[SillyOldDufferModerator @sillyoldduffer]

+1 to Thor's comment 'The sizes you need depends on what kind of work you do'. And not only the sizes; the metals being cut and the capability of the mill make a difference too.

I'm not an ideal role model for many reasons, but an outline of what I do and why with a ER32 equipped WM18 may help.

• Type of work: smallish and metric. I'm not fixing motor-bikes or building a ⅓rd scale Traction Engine. I'm mostly inside a 120x120x120mm envelope cutting mild-steel, aluminium, brass and cast-iron. Apart from gears and precision drilling, most of my milling could be done with a file. Eventually.
• A single 4-flute 10mm diameter carbide cutter is favourite for roughly hogging metal out quickly, dealing with hard metal, and punching through the outer skin of cast-iron. All my other milling cutters, apart from boring bars, are HSS.
• For cutting slots, a selection of 2-flute cutters. These range from 2mm to 20mm in diameter (but see comment on sets below.)
• For general purpose metal removal, 2mm to 20mm 4-flute cutters bought as a set with my 2-flute cutters.
• For flattening larger areas, a fly-cutter. (If I did a lot more area flattening I'd look at a multi-head carbide holder because they're faster.)
• For boring holes, carbide inserts boring bars to fit my boring heads. Carbide inserts save bother with sharpening.

Uncertain of what sized cutters I would need, I bought a boxed set. I haven't regretted it, but some sizes are used a lot more than others! Chaps who know what they're doing rarely buy sets, but I think sets are very helpful when learning and before tuning into to a particular interest. 12 & 10mm 4-flute cutters are most popular in my workshop but 8, 6, 4 and 2mm also get good airing. 20mm 4-flute is used often, but the 18, 16, & 14mm sizes are almost pristine. Up to 6mm diameter in the 2-flute range see plenty of action but I don't recall using the larger sizes at all.

I don't recommend starting off with second-hand cutters unless certain they're in good condition. At the outset, things will go wrong, and it's difficult to decide what the fault is when a learner driver is operating a machine that might be wonky, and might be using blunt tools on a difficult metal. (Avoid learning with unknown scrap – many metals absolutely do not machine well!) Second reason, milling cutters are hard to sharpen – you can't simply touch them up like a woodwork chisel. Later on, maybe: second-hand tools are a good option when you know what to look for.

Getting started with machine tools I found it invaluable to build a few simple model engines. Not because I'm particularly interested in model engines, but because they put me through my paces. The tools and techniques needed to turn lumps of brass, steel and aluminium into engine parts that fit well enough together together to run are useful later, whether interest takes you towards clocks or railway wagon axles. Making parts involves choosing tools: what's best for this particular problem? Your brain's the most important tool in the workshop, and it needs educating. The answers also tend to build up the tools you need: certain sizes 2, 3, and 4 flute cutters, twist drills (in tap sizes as well as ordinary), maybe countersink cutters, involute gear cutters, welders, brazing and an air-brushing outfit etc.

Metric vs imperial is worth a little thought too. Metric is almost certainly the best bet unless you live in the US, or are going to build scale models from imperial plans or work on older British machinery. In the UK metric is gradually pushing out imperial, making it ever more tricky and expensive to source certain items. (The internet is your friend.) What's done in your workshop is the decider.

Dave

[Jeremy Smith 2Participant @jeremysmith2]

All this information has been fantastic. Thank you all. I will be having him send me closeups of the cutters, as He is a few hours away. I will post the photos here shortly.

I am actually located in Canada, so I will stick with imperial.

Edited By Jeremy Smith 2 on 28/12/2020 03:04:11

[not done it yetParticipant @notdoneityet]

I am actually located in Canada, so I will stick with imperial.

I thought that Ca. was much more progressive than the UK in respect to going metric! Not much that is not metric in Canadian Tire, etc. Also, with a proportion of french speaking population, metric must be far more prevalent.🙂

Likely a requirement, even, in Quebec?😈🙂😆

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