Member postings for JA

Michael's suggestion of machine tools is worthwhile but I believe the block making machinery has returned to Portsmouth. From distant memories the clock gallery was excellent.

What is worth visiting is the Science Museum store at Wroughton, near Swindon, but it is closed at present. Twenty five years or so ago they used to have open days but now they don't seem to welcome visitors at all which is a pity since some items, such as large aircraft, cannot be moved elsewhere without great difficulty.

JA

For a strobe effect with flourescent tubes the light flashes have to be at the same frequency, inverse of speed, as the chuck or a direct multiple. In theory this could happen but in practice it is unlikely. I light my workshop with low Wattage flourscent tubes for general lighting and low Voltage halogen lights over machinery and have never seen a strobe effect.

Just to worry you, I recall an article written by someone who had looked at the strobe effect of incandescent lights. Surprisingly some effect was present with most lights and it could be significant. I think it was in The Model Engineer about ten years ago.

Before I retired at the end of 2007 we were using a powdered metal process. A bed of powdered metal was scanned by a high power laser which melted the powder. After each scan the unused powder was removed and replaced by a slightly deeper bed of powder. Items over 2 feet diameter and 10 inches high could be produced from any metal including high temperature alloys. OK, it was very expensive to produce a large item but the cost dropped rapidly if one was making a lot of small parts.

During my working life I only ever met first angle projection once. I had to produce a sketch modifying a complex flange and did not realise the original drawing produced by a German firm was first angle projection. Fortunately when the flange was set-up on the jig borer nothing made sense and I was called for.

Never assume a drawing is third angle projection. If it is not you can produce an awful mess.

Hi

First forum posting

If the steel swarf is on an iron/steel plate, lathe, vice, etc you will only pick-up about half of the swarf each time you use the stick.

Also sooner or later you will use it to pick-up a dropped tool which will then become magnetised. Don't worry, small pocket demagnetisers are starting to come onto the market, selling for about £10.

JA