Member postings for Colin LLoyd

Hey guys, thanks for all the input. Everything posted has great merit and a lot of information that doesn't appear in books. As a complete novice lathe and mill operator, it has provided me with both engineering and empirical advice which will be consolidated into a single laminated page that will hang by the lathe. Such is the power of forums and I am pleased that unlike some other forums, especially those dealing with computer problems, there was not a single "go and RTFM" reply for which I thank you. You will be hearing from this novice again.

Michael - I'm not sure I know what you you were trying to point out. My question was regarding the necessary precision for cutting speeds. The revolution values in the table provided by Neil were precise calculations from the table's cutting or revolving distances (e.g. carbon steel = 15m/min) - which in themselves were probably gained from empirical experience rather than any theoretical or experimental work. From a practical point of view, I questioned whether the table entries could have been rounded up to the nearest 10, 50 or 100 revs/min without serious consequences to the overall finished product. I said to round up because many mini lathes/milling machines cutting speeds are based on reducing the electric motor power supply rather than on gear changes. Such motor power reduction also reduces the torque of the motor and so rounding up will help to preserve the torque.

The topic appears to be, in general, somewhat personal in that many books on lathes etc have cutting revolutions that differ to the table provided by Neil. Some books lump together cast iron, steel and stainless steel in one column and brass, bronze, mild steel in another column. So the science is definitely not that precise - so the cutting revolutions should not express a precision that is not justified. I would not tell a cook to use a kitchen measuring jug marked in 50ml divisions to add 37.25ml of vegetable stock to a recipe when there was no appreciable difference to the meal if he just added 50ml.

If there are any engineering or scientific papers regarding the basis for the different cutting speeds for different materials, I would be interested to have a link to these or pdf downloads.

Novice lathe/mill operator here. I note the cutting speeds from the indicated pdf - but how crucial are the speeds? Surely rounding to the nearest 10 up to 100, 50 up to 1000, and 100 beyond that is sufficiently precise and more easily set with variable speed lathes lacking rev counters. But as I said - I'm just a novice - I expect to be corrected

Thanks Nick for the information about accessories for the Chester Mini-Multi. Looking at the Standard Accessories for the lathe/mill model, it seems that I managed to gain all of those with the purchase of the Chester on Ebay. Luckily - mine's faded red and not the bilious yellow on your picture.

Hi Carl - please explain your curious comment?

Hi Tony,

I have no idea what accessories might be available for the Mini-Multi lath/mill unless you are just talking about lathe and mill cutters. Is there a 4-jaw headstock available? Is there an alternative tool post - possibly a "boat" or "rocker" tool post.

I will start on the manual right away.

OK -with the recommendations so far and the old adage "you get what you pay for" I will buy some good mill tool bits. Now the problem is: is there a basic set of tool bits that will cover a reasonable majority of the work I initially plan to do?

Bear in mind that time is not of the essence - I'm quite prepared to do many passes with a narrow tool bit that could be performed with one pass of a wider tool bit. Most of what I intend to do at present is small scale - cutting region of 2-5 mm in both width and depth; both edge and channel cuts with flat and rounded bottoms. In materials brass, copper, mild steel and probably stainless steel.

I'm guessing an HSS set comprising 2mm end mill, 4mm end mill, 2mm ball end mill, 4mm ball end mill. Beyond that - I'm all at sea: no. of flutes and type of flutes? length of mill itself? No idea.

This is specifically to Neil about the Red Special: Brian's first electric guitar was one similar to an Egmond. a guitar that George Harrison had. And Brian and his Dad were already aware of the Fender and Gibson guitars and amplifiers being played by Buddy Holly, Hank Marvin, Eric Clapton and others of the late 50's and early 60's (The Red Special was planned and built over 2 years beginning in 1963 and made its first public appearance in 1966) . Brian's dad was an electronics engineer. From the recently published book about the Red Special it's clear that they both put in a lot of work into planning the instrument, creating test beds for the tremolo arm, made their own pickup wiring apparatus, etc. as well as acquainting themselves with the theory behind fret positioning for different scale lengths, etc. They knew about truss rod tensioning because they put their own home-made truss rod into the neck and Brian made his own fretboard curvature template and fret-curving clamp - things that any modern amateur guitar builder will make but was probably novel back then. The drawings and notebook entries shown in the book indicate that they had a thoroughly scientific/engineering approach to the design and manufacture of the guitar.

Hi Guys,

I seem to have produced a bit of confusion. I already have a lathe/milling machine - a Chester Mini-Multi. The reference to Chinese lathes was by way of introduction to the request for information about the quality of Chinese and Hong Kong supplied lathe and mill bits for my machine. They are generally much cheaper than those supplied from UK, Europe or US. Cheaper normally means lower quality.

However, I'm an amateur electric guitar maker and have found guitar parts supplied from China and the Far East to be of good quality - mainly because the vast majority of middle priced guitars are made in China and Korea.

The Chester machine is just a benchtop unit but seems well made and sturdy (I got it on Ebay a couple of days ago). I specifically got it because I am making an exact replica of Brian Mays Red Special guitar (The Queen guitarist for those who don't know) and need to make the bridge and tremolo units exactly as Brian and his Dad made them. So this gives the hint as to the size of the items to be made. Lathe and milling work will be of the order of millimetre grooves and working on items no larger than about 6 x 4 cm, mainly in aluminium, brass, copper but also some mild steel and stainless steel for the bridge string rollers. So the mill tool bits will be no more than a couple of mm in diameter - need ball end and end mill cutters.

I think between you - you have indicated that the Chinese tool bits may do the job but probably won't last as long as more expensive items. I would appreciate the web addresses of some recommended UK tool bit suppliers - as alluded to by Ian.

While I appreciate that Chinese made lathes are not regarded with much favour, is this also true of lathe and mill tools produced in China that are for sale on Ebay etc?. Is there a quality distinction between HSS and carbide tools from China?

Hi Neil,

After posting my question, I thought I'd start to download the manuals to see if any fitted the bill - luckily the Chester Mini-Multi was not too far down the page. The manual's photo's are not very good either on screen or printed out - so I wondered if I retook the photos using my mini-multi and inserted them into a re-vamped pdf manual for the Mini-Multi whether it would be acceptable as a replacement on the "manuals" list - or is there some legal copyright gotcha to doing this.

But anyway thanks for the quick reply and information. Do you have any more information as to when they were produced and for how long?

Colin

I've just got a second-hand Chester mini lathe/mill unit. No model name on the lathe - just a serial number 70092. Without knowing what model it is - it will be difficult to get the correct spares. Does anyone recognise this lathe/mill?