Member postings for Martin W

Michael

Is that 34min 30sec east or west of the Greenwich Meridian as was.

Martin W

All the gibs tightened/snugged up, half nuts clean and locking firmly, gear train driving the lead screw clean with no swarf/muck in the gears? Can't think of anything else other than obvious problems like tool chatter/spring, spindle bearings, belts etc.

Thanks for that Michael, no wonder that jeweled chronometers were so expensive to produce in those days with so much manual input required just to produce the bearings let alone the rest of the instrument. All I can say is thank goodness we don't live in the same world today. What with naked flames, exposed moving parts on machines, toxic/corrosive chemicals, and no PPE modern day HSE would have had a fit.

That said it is always interesting to look back to see how things were done, especially in times of need. Workshops with banks of lathes and their operators are now a thing of the past with cnc machines each producing more output and to a far higher standard than those workshops, progress yes I think so. You only have to look at modern car engines that run for over 200,000 miles and other than having a regular service never needing to be worked on.

Thanks again Michael for another interesting look at the world.

Martin W

OOPS

Sorry for my digression from topic Bob but the memory flashback reminded me of the fun we had as kids. That said I am glad you were entertained by the diversion.

Mick B1 that just raises a lot more memories, but nuff said for now.

Martin W

Noel

Probably a blessing that I wasn't aware of the existence of rocket rook scarers when I was younger as my digit count might not be the same as it is now, a full set.

Martin W

Buffer

That takes me back 50-60 years to the wilds of Wiltshire and bangers, bird scarers, on a rope. They certainly had a lot more thrutch than any legal firework you could get your hands on. Different times with different rules but we had a lot more fun it would seem and didn't harm anybody except maybe ourselves occasionally.

Thanks for the memory.

Martin

Michael

Had a look at the drawings in the wheellock article you linked and the dimensions looked a little clumsy, 3 decimal places. Did a quick metric conversion of several of these measurements and they have all turned out to be extremely close to sensible metric dimensions. It looks as if this was originally drawn in metric and then converted to imperial for the article.

That said it looks interesting so thanks for that.

Martin W

Great, I think it is brilliant.

Cheers Martin.

How about using a plain nut with a low strength and slow acting/setting thread retainer such as Loctite; other thread locking fluids are available. This way you get the best of both worlds with a nut that can be tightened with minimum force and after 24hrs or so a nut that will be more secure than a bodged nyloc nut, probably better than a non bodged nut.

If this is a fit once installation and you don't plan to remove the nut then use a medium or high strength thread retainer. Horses for courses as they say .

Hope this helps.

Martin W

Martin - Now that I like so much better than the parts being recycled into mass of baked bean cans. However I think that the perpatrator of the subject recycled unit should have it chained to his leg as an example of how not to do something.

Martin W

I would have thought that the risk is minimum as all the terminal blocks that can be seen in the photo are marked 'N' and the live wires appear to be terminated in screened finger proof enclosures. It only becomes dangerous if some muppet wires up the mains three pin plug incorrectly.

Many of us live with and use bog standard toasters where the live mains is easily accessed with metal objects i.e. cutlery, skewers, etc. all of which are readily to hand and make tempting tools, especially for little hands, for prodding/poking the internal workings of said item. How many of us actually think that when these devices are working that parts of the bare metal element are actually at mains live potential and relatively easy to access.

Just a thought

Martin

It's a thread definition/specification for UNC type threads much as we have Whitworth, BSF, BA etc thread definitions. If you want details then google #5-40 threads and you can get the actual diameter and pitch for each number.

Martin

Thanks Martin it's good to remember these unsung pioneers in whatever field they achieve fame.

Martin

Although a very low volume user of metals I will not buy any metal unless the seller gives the basic specification for that product. Motto 'If they can't be bothered to supply this data then don't purchase' no ifs or buts.

Martin

edit: re-worded

Edited By Martin W on 25/04/2021 09:56:48

Found this article on the BBC news site earlier. It's worth a read if only to see who is looking at your data and responses.

Martin W

Edited By Martin W on 17/02/2021 10:19:43

Clive

I don't know how large the venturi is but is there any merit in attaching it to a vehicle, out of the vehicle's local airstream, and measuring the vacuum produced at a number of fixed speeds. A simple manometer could be used to measure the vacuum at the different speeds and then using the same manometer the reading of vacuum measured at each speed could be reproduced and applied to the indicator unit. The actual value of the vacuum won't necessarily be known as this method will only produce relative displacement levels for each speed point, unless of course you choose to calibrate the manometer.

Just a thought

Martin

PS

Assistant will be required to monitor the manometer.

Edited By Martin W on 31/01/2021 18:22:04

It's not unusual to find 'fully plastic' earth pins on double insulated products as their only purpose is to open the gate on UK style 13A sockets and clear plastic on 13A plugs have been around for quite some time though they are not my style.

Martin

Michael

That is absolutely brilliant, the way that the plates are formed and laid out look like the muscles of the real beast; then there's the head which takes it to another level.

Thanks for sharing it.

Martin

If the DB8VS has the same arrangement as the DB7VS then the pulleys are plain V section and don't have teeth. The only reason for using a toothed V belt would appear to be to give it the extra flexibility to accommodate the motor drive pulley diameter. If so then the number of teeth per unit length is irrelevant.

Martin

Michael

If I could do that leads or batteries or what I would be a very happy man !! Thanks for sharing and it really shows the progress of technology to date. I remember a James Bod film where there was a tracking system that displayed the target on a visual display system and I thought "Yeah really" yet a few years later along came GPS and map tracking. I really wonder what the future holds in the development of technology especially with the introduction of Ai etc,

Thanks and stay safe.

Martin