Product category:
CNC automatic lathes
News Release from: Geo Kingsbury Machine Tools | Subject: Index MS32B CNC multi-spindle automatic
Edited by the Manufacturingtalk Editorial
Team on 26 June 2002
Tradional cam automatic user invests in
CNC
Traditionally a cam-type multi-spindle lathe user, a subcontractor has started to invest in modern CNC six-spindle automatics, with very positive results.
Traditionally a cam-type multi-spindle lathe user, Eastleigh subcontractor GW Martin has started to invest in modern CNC six-spindle automatics, with very positive results The company installed an Index MS32B in June 2000 and, notwithstanding its relatively high capital cost, the increased production output justified the purchase of a second Index CNC multi within six months
This article was originally published on Manufacturingtalk on 26 Aug 2003 at 8.00am (UK)
Related stories
Foundry's mill-turning investment ups exports
Coventry-based foundry has upheld and expanded exports by adding on high-tech mill-turning centre facilities to machine turbocharger impellers supplied to Italian and US customers.
Pick-up spindle lathe has hexapod features
A new, hanging-spindle, vertical turning lathe (VTL) has been introduced by Index on which the spindle head is able to move freely in three dimensional space.
Both were supplied through UK agent, Geo Kingsbury Machine Tools.
The initial investment followed an enquiry from an existing GW Martin customer who wanted to double production volumes of a particular part to two million a year.
The mild steel vehicle component is 32 mm in diameter and manufactured in three different lengths.
Further reading
Vertical turning lathe takes on complex production
New from Index is the option to fit a four-axis CNC tool turret in addition to a standard two-axis turret on the German manufacturer's V300 vertical turning lathe (VTL), allowing the production of mor
Brass turning on CNC lathes
Leipold (UK) uses eight Index 6-axis CNC lathes supplied by Geo Kingsbury, the latest two installed during May and June 2000
Bigger envelope vertical-spindle machining centre
The new, Spanish-built Kondia ZM-99 vertical-spindle machining centre from Geo Kingsbury MHP has a working envelope more than 50 per cent larger than the CM60-MA model which it replaces.
Says Paul Skelton, production manager, "We would have needed four or five manned cam multi's to cope with the increased throughput.
This was not the answer, however, as to retain the business we needed to reduce unit price by a few per cent and this would have cut our margin to the point where it would have been uneconomic.
"We used the contract as a way into CNC multi-spindle turning, mindful that the automotive industry in particular sources parts globally so we are in fierce competition with subcontractors not only in the UK but also from overseas, especially in Germany, France, Italy and the USA.
We knew that the way forward was to invest in CNC multi's owing to their high productivity and low manning requirement.
In our view, companies that do not embrace this technology will find it increasingly difficult to compete in mass production of precision turned parts." Even though the vehicle component requires relatively simple drilling, boring and threading operations, the first Index multi allowed GW Martin to quote a competitive price that won the contact.
Paul Skelton says that despite the component's simplicity, the CNC multi is three and a half times faster on this job than a cam machine.
To fulfil the contract, the Index machine operates 100 hours per week with minimal attendance.
The reason for the high productivity of the MS32B is that, unlike conventional cam-type multi's on which all the spindles have to run at the same speed, all six spindles on the CNC machine may be controlled independently.
Each may therefore be run at different, infinitely-variable speeds, allowing the cutting conditions to be optimised at each station.
This was the main reason for Paul Skelton selecting this machine rather than other CNC multi's on the market.
He continues, "The automotive industry these days demands zero defect production.
Whilst the vehicle component is relatively simple and the tolerances do not even begin to tax the MS32B's capabilities, the fact that it is made from 070M20 mild steel bar means that a consistent result is difficult to achieve on a conventional multi.
"This is because the parameters can be optimised at only one spindle and are almost certainly compromised at all the others.
So when 070M20 is machined, the swarf often comes off in long strings on a cam-type multi because we cannot create the right conditions for the cutting insert's chip-breaking geometry to work effectively.
Another drawback is that we frequently have to use a conventional tool such as a tap where what we really want to do is single-point cut the internal thread.
"Also, we cannot use carbide tooling efficiently on the cam machines because the 2,000 rpm spindle speed is not high enough, whereas the 6,300 rpm of the Index spindles solves this problem, so we use carbide at every position." The second Index multi, another MS32B, is equipped with extra X/Z compound slides.
All but two stations on the latest machine are thus equipped, facilitating complex work involving in-cycle milling / drilling.
As the subcontractor's experience of the Index multi's progresses, it may consider retrofitting further equipment for such operations as eccentric drilling and polygon turning.
While this type of work is still high volume, it nevertheless requires the machine to be reset, say, every month.
A further advantage here is that changeover for a repeat job is much faster than on a cam-type multi, and set-up for a new part provides even greater time savings.
Established in 1959, G W Martin is well qualified to comment on the application and performance of automatic lathes, having operated about 30 Index single-spindle machines throughout the 60s and 70s, all bought through Geo Kingsbury.
Eight Wickman cam-type multi's were installed during the late 80s and early 90s for bar sizes from 1 inch to 21/4 inches.
A continuing programme of capacity upgrade saw the introduction of five Index ABC mill-turning centres in a 12 month period during the mid 90s.
The company now operates 36 lathes as well as 12 machines for prismatic metalcutting plus sundry other plant.
Today the ISO 9002 / QS 9000 approved subcontractor boasts an impressive production facility that provides a one stop machining and assembly service.
Turning is currently predominant with prismatic machining a current focus of expansion.
All types of material are machined in medium to large quantities.
Some 55 per cent of the company's turnover is in the automotive sector, with the remainder mainly in the aerospace and electric motor industries.
• Geo Kingsbury Machine Tools: contact details and other news
• Email this article to a colleague
• Register for the free Manufacturingtalk email newsletter
• Manufacturingtalk Home Page
Search the Pro-Talk network of sites
