Member postings for Swarf, Mostly!

Hi there, David,

Regarding your lead-screw and auto feed, lubrication is your friend. Also, make sure your lead-screw is rust-free - rust is abrasive.

Regarding the auto feed, the precise value of the pitch is irrelevant, it just needs to be fine. Lay out all your change wheels on the bench in order of size, smallest on the left and largest on the right. Fit the largest on the lead-screw and fit the smallest on the intermediate stud. Fit the next largest on the intermediate stud keyed to the small one already there. Fit the next smallest on the tumbler, fit spacers where necessary and adjust stud and banjo until all the gears mesh. (feed a strip of paper between each pair of meshing gears while tightening the stud and then remove the paper.) If the combination you've chosen won't mesh, swap gears until you get a combination that does. For fine feed, you want small drivers and large drivens.

Check for free rotation, switch on and assess the feed-rate. If it's so slow you fear you'll die of boredom, swap gears to reduce the ratio of the meshing pairs and re-adjust the banjo and studs to restore correct mesh and test again.

It's quite easy to proceed by trial and error until you get a set-up that's OK for the job in hand but do be prepared to get your fingers greasy. (I lubricate my change wheels with spray-on chain oil.)

Best regards,

Swarf, Mostly!

Hi there, Maurice,

I went to my nearest Plumb Centre branch (Horndean, Hampshire) today - they didn't know anything about a special offer on pressure gauges! All I was offered was a gauge with hose for £13-ish.

The other end of the hose has a 3/4" BSP union nut made of plastic (similar to the end of a washing machine hose). Seems a bit on the big side for 'our' purposes!

Best regards,

Swarf, Mostly!

Pete,

You omitted to say:

"The guarantee expires when the van turns the corner at the end of the road" !!

Best regards,

Swarf, Mostly!

Mercury will amalgamate with many metals - aluminium among them. That's why it's not allowed on aeroplanes - aviators get twitchy at the thought of their airframe dissolving away in mid-air!! (I've expressed that in a humorous way but it's really far from funny!!! )

When I was working for an avionics company we bid to supply a helicopter-borne equipment - one of the contract conditions was that we had to warrant absolutely that our equipment would not contain mercury, however enclosed.

As a consequence, I wonder whether that's also why Royal Mail won't accept mail containing mercury - at one time they had a pan-UK aeroplane shuttle service to move mail around the UK overnight, I don't know if that's still operating under the new regime? Or whether Royal Mail's refusal is simply on environmental grounds.

Best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 14/09/2015 16:37:47

Hi there, all,

I hope you're successful in disposing of your Hydrofluoric Acid in an ecologically sound and inexpensive way.

What observations/advice/comments have folks got regarding metallic mercury? I seem to live just about as far from any/all of the barometer refurbishers as UK geography permits!!!

Best regards,

Swarf, Mostly!

Hi there, Jon,

Before I moved to sunny Hampshire, I did a stint on my local IEE Area committee. The committee members worked hard to arrange a programme of interesting lectures for the members. Nowadays I try to get to the monthly lectures arranged by the Solent Retired Members Section. That programme, too, is varied and interesting. Maybe you should have a look at the lecture programme in your area?

Best regards,

Swarf, Mostly!

It was really quite gentlemanly of the IEE to describe it as a merger. I'd describe it rather as a benign rescue takeover. The IEE had succeeded at recruiting University leavers and their distribution of membership numbers vs age was fairly flat. The corresponding graph for the IERE was a hump at the older end, inexorably moving to the right at a rate of 12 months per year - we were doomed, I tell you, doomed!!!

Best regards,

Swarf, Mostly!

Hi there, Roger,

I second what has been written about the balance difficulties - I had an un-tutored assistant to help me lift the lathe (at that stage with the motor still in-place) off its stand. It took us by surprise and we managed to bend one of the bolts in the raising blocks. Fortunately, Myfords (at Beeston then) had spares.

Last time I moved my ML7 I had to get it from the car (an estate ) to the bottom of the garden. I used a builder's wheelbarrow. The barrow has an inflatable tyre which made the bumpy ride an awful lot easier than it would have been with a solid tyre.

The lathe was lifted off the barrow on to a pile of railway sleepers (part of the garden 'landscaping' ) just opposite the shed door. We then rigged two scaffold boards, one on top of the other, as a bridge through the shed door and slid the lathe up on to the bench. That got it to the same level as the previously positioned stand. From there it was a manageable two-man lift on to the raising block bolts. It helps to position a few pieces of wood in the swarf tray to support the weight of the motor until the mounting bolts are secured.

An 'island' position for the lathe stand is much to be envied. In a workshop as small as mine, the lathe has its back close to the wall and attending to the motor wiring or motor mounting bolts is a pain in the derriere!

Best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 27/08/2015 12:30:07

Edited By Swarf, Mostly! on 27/08/2015 12:31:16

My first lathe was a quite old Carl Hurth, it was made in Germany but all the threads were Whitworth.

Best regards,

Swarf, Mostly!

Hi there, Robin,

Here, if I can make it work, is a link to a YouTube video by Tom Lipton (aka 'Oxtoolco' ) entitled 'Albrecht Chuck Rebuild'.  Be patient until the advert has finished - it only lasts a few seconds!!!!

I thought this might be of interest.

Best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 17/08/2015 13:35:23

Too subtle for me!!!!!!!!!!!!!!!

Would someone please PM me to explain?

Best regards,

Swarf, Mostly!

No, if I remember correctly, it was bought from an Amazon associate! The item concerned was the mains cable for the PSU for one of those caseless harnesses to connect a hard drive to a USB socket. We've actually had a few of them.

The pins broke off so easily that I could imagine a clumsy user ending up with a detached pin still in their wall socket. Caveat emptor indeed!!!

We also bought a KVM switch from another Amazon associate but had to return it because it came with a non-UK AC adaptor. (I tried a few Euro-to-13A adaptors but didn't consider any of them acceptable for 12/7 use!!! ) The associate concerned was operating from mainland Europe. The manufacturers of the KVM switch told us that all their UK agents supplied the equipment with an AC adaptor suitable for UK sockets. So we cancelled on Amazon's associate (goods not fit for purpose) and bought from a UK agent.

Best regards,

Swarf, Mostly!

Please excuse me if this is off-topic.

I recently removed a moulded-on pseudo-13A plug from an item of far-Eastern made computer equipment. (The plug did not have a fuse-holder so was illegal. ) I substituted a proper 13A plug. The pseudo-13A plug did, at least, have shrouded pins.

Thinking that I might as well salvage the pins to add to my scrap brass box, I applied a pair of pliers. To my surprise, the pins broke much more easily than I expected revealing that they were not brass but brass-plated die-casting alloy!

Best regards,

Swarf, Mostly!

Hi there, John,

Please could you add to your list whether the screws are RH or LH thread?

And whether they are square thread or Acme?

Best regards,

Swarf, Mostly!
 

Edited By Swarf, Mostly! on 09/08/2015 14:46:18

Hi there, Brian,

Why don't you make your own count wheel? If you have either 'Electrical Timekeeping' or 'Electric Clocks and how to make them' both by F. Hope-Jones, they each include a drawing of the count wheel.

One merit of the Synchronome is that the pitch accuracy of the count wheel isn't too demanding - it only has to be precise enough for the pawl to gather at least one but not more than one tooth at each swing of the pendulum. Subsequent action, i.e. release of the gravity arm, only occurs once per revolution of the count wheel.

I'll retreat to my dugout now!!!!!!!!!!!!!!!!!!

Best regards,

Swarf, Mostly!

Posted by Windy on 20/07/2015 13:06:15:

SNIP

This one (in front) rather reminds me of the Allard in which the Librarian used to arrive each morning at EMI's plant at Feltham, Middlesex. Back in the sixties, that is. (Naming no names!)

Her husband was a much-published motor sport photographer. (Still naming no names!)

Best regards,

Swarf, Mostly!

Hi there, John,

If you're going to make a large number all of the same size AND if you have collets for your lathe, it might be worth investing in a square collet.

Alternatively, four-jaw self-centering chucks do turn up on eBay now and again.

A tailstock turret and a sliding die holder will help with the bolts while a nut tap (standard length thread plus a long shank) will help with the nuts.

All of that assumes that you're going to use square stock of a standard size; if you have to machine standard square stock to a non-standard size, then I guess you'd need a mill or a shaper?

Best regards,

Swarf, Mostly!

Fire extinguisher, maybe even two!

Hi there, Alan,

Could you insert some packing under the rear of the machine and then insert the hose from a wallpaper steamer through the access holes?

Maybe do a test first to see if steam heat renders the 'gunge' fluid enough to drain to the front.

Best regards,

Swarf, Mostly!

In my amateur radio days, our club used to run its National Field Day stations from a single cylinder diesel generator. Although our usual site was fairly rural, there were houses within earshot, especially at night when the ambient sound level was otherwise low. We attempted to confine the diesel noise by 'circling the wagons' around the generator with three or four cars. It owed more to wishful thinking than to acoustics!

The diesel noise is predominantly low frequency, difficult to silence, and I used to wonder whether the noise from a gas turbine, being higher in frequency, might be easier to suppress. It would have been interesting to lay hands on an ex-aircraft APU but I had no idea whether such an item would have been available, from where and at what cost!

Drag racers seem to get quite large gas turbines from somewhere so it must be possible.

Another big unknown was the maintenance burden for an APU. Do they run for the whole duration of a flight or just until the main engines are running?

Oh, well, interesting but not on my project list anymore!!!

Best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 17/06/2015 13:20:18