Posted by Daniel Bird 1 on 14/06/2020 21:16:26:
I would like to buy a new set of ER32 collets … i'm really looking for information about what is available on the market
I use a bolt on chuck bought from arceurotrade, it has 0.01mm runout in the taper.
inclined to go for a precision set because apart from price i can see no other downsides…
I like to buy tools of good brand name but …
…
Any other suggestions to consider would be gratefully received.
Thanks
If money is no object, approach an Industrial supplier and buy top-end collets. As the best are about £40 each, all the sets listed by Daniel are "cheap", but that doesn't mean they're rubbish. Look closely at what a £40 collet delivers. They're costly because they're balanced to run at CNC/Carbide speeds, about 40,000 rpm. Is it worth buying one for an ArcEuro chuck in a GH600 lathe? No – waste of money!
If precision is essential, necessary to consider the whole tool-chain. A precision chuck is needed to get the best out of precision collets, and a precision machine is needed to get the best out of a precision chuck. The cost rises rapidly, is it justified?
As Model Engineering is a hobby, chaps are free to spend their dosh as they wish. Nothing wrong with filling a workshop with 'quality' tools and enjoying them. It's not what real engineers do though! To them 'quality' is a red-rag to a bull, because it too often means buying on hearsay and emotion rather than cold logic. Adverts, history and personal opinion are inferior to taking a balanced view. Real engineers satisfy requirements; choices aren't based on quality, rather they target 'Fit for Purpose' and 'Value for Money'. Buying by Brand comes unstuck for two reasons: it wastes money whenever cheaper would do the job and it fails when better is needed. Nuts and bolts are an example; DIY Store fasteners are OK for domestic purposes but a poor choice for weight bearing, car brakes, maritime and – god forbid – aircraft. And only a dingbat would buy aerospace fasteners to patch up an old garden gate! Best to engage brain and ask what tools are for!
Hobby lathes are what they are. Buying a GH600 means a choice has already been made. It's a general purpose lathe good for work in the 0.02mm (1 thou) region. With care the operator can do better, but it takes time and effort. For what I do, 0.02mm is almost always good enough. I have a lathe collet chuck and a budget ER32 collet set (about £120) bought from Warco. I've not bothered measuring collet run-out; instead I cut the chuck's register slightly loose so work can be centred more-or-less exactly by tapping the backplate with a mallet before nipping up the bolts. Works well, but precision gear would save lots of time if I did a lot of high accuracy collet work. I don't!
In practice, 75% of turning in my workshop is done with an inexpensive 3-jaw chuck (0.05mm run-out 50mm out from the jaws.) 4-jaw about 20% of the time because work can be re-centred accurately in it. Collets rarely when jobs benefit from quick resetting, and/or is transferred between lathe and mill. That's just me – a clockmaker would favour collets much more highly.
Bear in mind that the old guys did excellent work on worn or indifferent machines without calibrated dials & micrometers. Spring calipers, chalk, wobblers and fitting are effective down to about a thou, the disadvantage being the time and skill required. Bees knees tools save time rather than enable new marvels. There's a good chance an ordinary hobbyist doesn't need top-end tools unless making something special like one of Barrie Lever's high-performance engines. Wanting to own nice tools is a different matter, but be honest: is the money spent for engineering or emotional reasons!
Arc Euro are good at matching value for money tools to value for money machines. Buying from them (and other thoughtful suppliers) avoids the worst of ebay and filters out the tempting expensive stuff. Owners of ex-industrial machines might be justified in going up-market, but so much depends on how their machine is used. Pootling in sheds and my breed of light hobby engineering is a world apart from a professional 'time is money' jobbing workshop. An advantage of buying upmarket products is they should be reliably specificied; but eyes wide open – they won't be cheap. Always consider if money can be spent more effectively elsewhere.
Newcomers often jump into the deep-end by stripping down machines and measuring stuff like run-out. Both risky and confusing without a certain level of experience, not least because operator error causes much grief early on. I suggest finding problems by cutting metal at first. Put the machine through it's paces. If it performs 'well-enough', don't fret! Look for causes and ask for advice only if it misbehaves. At the moment Daniel proposes spending up to £332 replacing collets when it's possible his cheap set is good enough. My advice, get used to the lathe and it's accessories and decide what it's for before parting with cash.
Dave