Member postings for mgnbuk

use Firefox as your browser and install adblock plus

I use Firefox and Adblock Plus, but still get the adverts either side of the text & have the overlapping problems. How do you configure Adblock Plus to get rid of the adverts on this site, please ?

Maybe doing away with them would speed up the page load times - I have 30Mb cable broadband, but this site is always sluggish & un-responsive.

Regards,

Nigel B.

A method I have used sucessfully on my Super 7 was described in this thread

http://www.model-engineer.co.uk/forums/postings.asp?th=64457

HTH

Nigel B.

TS Harrison are still in business - have you tried them ?

For all enquiries, please contact 600UK

600 UK
PO Box 20
Union Street
Heckmondwike
West Yorkshire
WF16 0HN
UK

Tel: +44 (0) 1924 415000
Fax: +44 (0) 1924 415006
Email: [email protected]

Being industrial machinery suppliers, parts (if available) will not be cheap. But they should fit !

Regards,

Nigel B.

our cars are propane - I did some research and uk autogas is almost pure propane all year round

Not so. Autogas is a predominatly a propane/butane blend & the proportions vary according to season. Winter is around 70% propane, summer around 70% butane. Plus "other stuff" gets added in varying amounts depending what is available & the "mix" varies by manufacturer.

I ran an lpg converted Kia Carens for 4 years / 70k miles & my current Toyota Avensis is in the workshop being converted at the moment, so have a bit of experience of the stuff. Through experience, I try to avoid Calor & Shell, as both of those gave poorer consumption than other brands - a bit more of the "other stuff" in the mix, maybe ?.

German pumps show the fuel composition seasons on a sticker on the pumps, so you know what you are getting when you fill up. Much like "Winter diesel".

Nigel B.

I have checked a couple of sets of Lidl / Aldi digital calipers against slip blocks & found there to be no difference in readout accuracy to more expensive brands used at work.

I find it amazing that these devices can be retailed so cheaply - the quantities manufactured must be incredible. I paid more for a Polish vernier caliper 15 years or so ago than the digitals sell for today. Mind you, the vernier caliper continues to work when it is cold - the downside is the need these days to require a magnifying glass to read it !

Nigel B.

If your leadscrew is worn & your lathe is long enough to traverse the thread length, you could re-cut the thread slightly thinner to get it even along the length & screwcut a nut to suit. That was the method employed during lathe refubishment by a company I was seconded to as an apprentice to widen my experience - I was paid car mileage rates to deliver the worn screw & nut to the machine shop & collect the refubished screw / new nut on my motorcyle. I had the screw (the cross slide screw from a Herbert lathe IIRC) strapped length-wise along the bike.

Regards,

Nigel B.

IIRC the "normal" centre height for a Boxford was nominally 4 1/2" (I seem to recall the actual centre height was 1/16" or 1/8" over 4 1/2" ). but 5" versions were also made. You would appear to have the latter. Have you tried contacting Boxford with the serial number ? They are still trading, having moved recently to a new factory in Elland, about 6 miles or so from the original Boxtrees Mill site in Halifax.

http://www.boxford.co.uk/boxford/

how are internal splines cut?

Broached

Apparently it's a very good lubricant.

Some years ago I commissioned a CNC convereted Keller horizontal milling machine. The Keller originally used an electrical copying system - feed to the axes via electric motors and clutches, controlled by a fancy switch arrangement at the stylus. I have seen pictures of these machine producing aircraft propeller blades during the last war.

The machine had been converted to a CNC gun drill, with the original spindle axis being replaced with a Mollart gun drilling slide assembly on a rotatable mounting. The Keller specified slideway lubricant was Sperm whale oil - apparently nothing else would do, as the sperm whale oil gave very little stiction & produced a much better surface finish. At the time (probably early '90s) the originally specified oil was stil available from Mobil, though I seem to recall that it was very expensive.

The machine was supplied to an automotive toolmaker on the south coast, used to put cooling & plastic injection channels into large injection mould tools (i.e. car bumper mouldings). I particularly remember this machine due to the failure of a part of the coolant system during initial drilling trials - the gun drill used high pressure coolant & the MTB had replaced the original coolant hoses with high pressure items. But he had retained a swivelling cast iron block mounted on the machine column, used to allow for the movement of the head up & down the column.. I was stood in front of the machine during the first cut when the casting burst - covering me from head to foot in neat cutting oil.

Nigel B.

The saddle stop can be a simple block that you clamp to the lathe bed, or a more complex arrangement with a turret that allows several independantly adjusted stops to be rotated into position. This would allow several positions to be repeatably attained rather than just one.

Some lathes have a slipping clutch built in to the feed drive - others don't. We had a large-ish Colchester at work (Mastiff, I think) that could be left to run up to the stop un-attended. When the saddle contacted the stop the clutch slipped. The Harrison VS330, though, does not have a clutch - when one of my collegues who was used to the Colchester used it, he broke a roll pin on one of the apron drive gears by letting the machine run to the stop under power feed.

I am not familiar with manual Weilers (I retrofitted a CNC one many years ago - quality machines), so I suggest it would be prudent to try and ascertain whether or not the saddle feed drive has a clutch fitted not before trying running up to a stop under power.

HTH

Nigel B.

You beat me to it, Steve !

I got an e-mail notification of this sale at work today & had intended to post it tonight. The sale is "The Estate of Mr W J Stacey" according to the sale details.

Regards,

Nigel B.

There are two tapped holes at the end of the Y axis shears on the front of the knee - I am pretty certain I have seen this type of machine fitted with a brace like that from the overarm to the knee to minimise deflection (of knee or overarm) under heavy cutting conditions. The large slot would appear to be to clear the Y axis screw boss.

I would expect the overarm to be brough further foward than it is shown in the picture, with the bracket fitted to the overarm dovetail - the large slot passing over the Y axis screw boss & secured to the knee via bolts into the two tapped holes.

£0.02

Nigel B.

Only use grease in rolling element bearings - an appropriate grade of oil for everything else.

Using grease on the slideways is a guaranteed way of reducing the life of your machine - the grease holds fine swarf, mill scale, rust etc. & forms a very effective grinding paste. Regularly applied oil flushes these normal products of using the machine out of the slideways.

Look to industrial practice - CNC machines with conventional slideways use automatic systems to regularly apply slideway oil directly to the moving elements. Grease is only used in machines with linear bearing guides - even then, most machines so equipped tend to use oil in my experience.

Regards,

Nigel B.

Good quality SKF were only £30 ish last year.

They may be "good quality", but I doubt that they were precison (P6, P5 or P4) at that price.

And there is a very good chance that the "quality" brand was made in China as well.

Not directly relevant to the question asked, but I have run an LPG converted car & all the advice for operating on LPG (variable propane / butane mix according to season) is that LPG takes more igniting than petrol. Spark plug change intervals are reduced - even with Iridium plugs - to maintain ignition efficiency.

Nigel B.

I pull mine up pretty hard (Emco FB2 clone with 2MT spindle), but the machine has a captive drawbar so it also jacks the tool out with no hammering required. The spindle nose has two flats & the machine was supplied with a spanner to suit - the drawbar has a 6mm AF hexagon socket. The two combined offer a good grip to tighten or release the drawbar without stressing the bearings.

I made a face mill holder that, when inserted by hand, is around 2 thou clear of the spindle nose - tightening the drawbar brings the back face of the holder into firm contact with the end of the spindle nose. This is similar in principle to HSK or Capto tooling & makes for a stiffer connection, but also requires a good pull on the drawbar to accomplish..

I have not had any problems with tooling coming adrift in operation - likewise no problems extracting tooling after use, though it sometimes releases with a bit of a crack !

I also have an RF30 mill drill (3 MT taper) that has yet to be used in anger. That will require the drawbar to be made captive to remove the need to pound on the bearings while removing tooling.

Nigel B.

If you discount machines with round columns, tilting slides & swivelling heads you will not find a lot of choice !

I noticed a small ad in the latest issue of MEW for an Axminster 6 speed milling machine (in Derby, I think) - IIRC, these are Taiwanese clones of the Emco FB2 & Axminster marketed them as the "VHM", as the head can be swivelled to place the spindle horizontal for more machining options - the column also rotates in the base to give even more options. It has a 24" by 6" table, with 15" by 5 1/2" travels - 2MT spindle in a quill with 1 5/8" stroke and 6 geared speeds - around 14" maximum clearance between spindle & table - these are compact machines but with a reasonable capacity. Look up the FB2 on the lathes.co.uk site - the clones are all but identical.

While this is a round column mill, it has a full length key to maintain head alignment. It is also swivelling head (as above), but my similar machine is no great problem to align & it doesn't seem move out of position under reasonable machining loads. If I could find any shortcoming, it is the lack of fine feed to the quill. I have an Emco brochure for their original machine which gives the weight as 110kg - the column & head removes easily from the base as a unit, and I could move each part on my own (with a bit of puffing & grunting !).

Get in quick while it's still available !

Nigel B.

These laser point and read devices are particular about the type of surface you point at

Be aware also that the alignment between the point that the measurement is taken from may not be accurately aligned with the laser dot.

We came across this during attempts to accurately measure temperatures across a flat heating element at work for a development project - the readings from the hand-held meter did not seem "right", judged from readings given from other areas of similar colour (the element was glowing dull red).

Experimentally rotating the meter while keeping the laser spot on the same point gave different readings, suggesting that the actual reading was being taken from one side of the laser spot. In our case, when attempting to take a reading from the LH edge of the element the actual reading was being taken off the side of the element in fresh air & hence gave a much lower result.

This may not matter for large areas, but is something to bear in mind if an accurate spot reading is required.

Nigel B.

Best candidate for jointless flat belts is PolyVee turned over.

It will probably offer more grip that way round as well !

Flat belts should be available from any good bearing / transmission supplier.