|2645 forum posts|
I read a short piece some time ago by a guy who worked in China, that they like to save money whenever possible and will not replace measuring equipment like temperature probes etc as often as they should. As a result basic materials like steel and iron may not be up to specification. Obviously if the material is for critical engine components etc then hopefully it will be properly tested before too many components are made from it. I somehow doubt this happens for things like hobby machines though.
|Neil Wyatt||21/10/2020 18:31:29|
18325 forum posts
Deflection of a beam varies as the third power with length.
Taking the ratio of centre distance to the power of 3 to overall weight makes the differences much less dramatic:
OK that's a crude measure, but a first approximation it's reasonable - especially as I haven't made any reduction for centre height. Note also that these machines are not intended to perform the same duties (and also that a large part of the weight in the colchester is in its stand).
Edited By Neil Wyatt on 21/10/2020 18:32:20
|Alan Ambrose||22/10/2020 13:26:17|
|8 forum posts|
Nice Just for grins, I've been calculating cost/Kg of various lathes & mills I'm getting numbers generally between 10 & 20 £/Kg.
Maybe cost / specific stiffness next (never mind the quality)?
|Michael Gilligan||22/10/2020 16:31:59|
16674 forum posts
Today’s scrap value for Iron is about nine pence per Kg
... so now you can work our what manufacture and distribution are worth, and guess the profit margins
I would like to think that the skilled labour and/or high precision machining centres represent a significant portion of the purchase price ... but who knows ?
|Dave Wootton||22/10/2020 17:17:04|
|86 forum posts|
I didn't really want to get involved in any arguments, but, as a long time user of Colchester and similar industrial sized lathes, both at home and at work, I thought I would add just a few comments based on experience of using a Warco GH1322 lathe in an industrial setting over a period of over five years. probably 15-25 hours a week on all manner of work, most of which would equate in model terms to that involved in a large scale traction engine.
I reacted in horror when told that I was to be put in a satellite workshop newly equipped and on turning up found a Warco lathe and Bridgeportish clone mill. Despite my protestations I found after a couple of weeks I liked both machines, they were capable, accurate and rigid. Lots of screwcutting, press fits, intermittent cuts on fairly lumpy castings and fabrications the Warco coped with it all. the three jaw chuck was as accurate as any and was still good when the place closed down in April. So despite not being as well finished as some, it did the job under difficult conditions, always someone asking how soon can we have.....
Not wanting to start any rows but I did want to point out that these imported machines, may be lighter built and not as well finished, in my experience of this machine it actually did the job, which in industry is what matters.
I worked at a firm in the early 1980's that took my war finish big old Holbrook lathe and replaced it with a new Colchester Triumph, The Colchester could never achieve the finish of the Holbrook, I missed that lathe terribly.
I think I'm reasonably unbiased I've got a Bantam 2000 at home.
I'll go and put me tin hat on!
Edited By Dave Wootton on 22/10/2020 17:20:08
Edited By Dave Wootton on 22/10/2020 17:20:42
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