Member postings for John Doe 2

Surely a 5mm diameter hole in 1/4" plate could have its corners opened out with a square file in not too much time. Although I agree; 80 corners would be a bit of a b*ll ache to do !

Alternatively, think laterally: I would be inclined to find a company to laser cut a series of 5mm square holes in a sheet of metal, spaced appropriately so you can cut them out and fabricate the rest of the device around each hole.

Or maybe there is a tool or widgit available with a 5mm sq hole that you could buy in then attach to the devices you are making?

For example, a quick look around my tools found this Knipex cabinet key tool, which has a 5mm square hole in the centre there. But a laser cut sheet would be cheaper and easier probably.

Edited By John Doe 2 on 12/05/2023 10:14:27

No offence, but I think you would probably be much better off using an actual battery drill to drive your lathe carriage.

You can sometimes buy second-hand DeWalt, Bosch, Makita battery drills from those high street shops. All the electrical supply, gearbox, speed control and reversing switch would be there as part of the drill. And they have high torque. You would simply need to fabricate a mounting to secure the drill onto your wood turning lathe carriage drive.

Without understanding electricity, you might spend a lot of time and money otherwise.

PS, Note : Domestic light fittings are still live even when the light they feed is switched off.

Edited By John Doe 2 on 12/05/2023 09:28:06

Slightly nervous about Dave's last bulleted statement - perhaps I am reading it wrong :

240V mains IS a widow-maker potentially, (no pun intended). Any "electrical newbie" needs to be 100% aware of how dangerous the mains supply can be in the hands of someone who clearly knows nothing about electricity. Much lower voltages than 240 V can kill - hence why building sites, where it can obviously rain, use a centre tapped 110V supply for their power tools, resulting in only 55V between either conductor and earth.

UK mains can kill. Be under no doubt. Please be extremely careful. Better still, don't dabble with it.

PS, the wire you are proposing for the motor sounds much too thin. You need at least 10 Amp wire, which, (from memory, so please look it up), would be 1.5mm Sq cross section per conductor.

Edited By John Doe 2 on 11/05/2023 23:08:31

Very impressive engineering.

Dave, your investigations are fascinating, but I forget now what you are aiming to achieve - a near perfect pendulum, or a near perfect way of measuring a pendulum's performance?

One thought: How do you know if the bob is swinging exactly beneath the suspension? i.e. you have securely fixed the razor blade element at both ends, but how do you measure that the bob is hanging exactly below that point and not held very very slightly off to one side? Ditto, how do you know that the razor blade will flex along a line exactly 90° across and not throw the pendulum bob slightly off to one side?

Do you not need one fixing to the razor blade arranged to allow sideways movement as well as movement in the plane of the pendulum swing? Otherwise the pendulum might be slightly skew, which would affect it's swing? Apologies if this has been mentioned - there are a lot of pages to read through now !

The two main things are :

mix with other people, and

mix with young people.

Both are essential to keep your brain alive and active. Without such stimulation the brain will atrophy, with very bad results.

For those with a workshop who have fallen out of love with making models, I suggest advertising to make things in metal for people.

You might not know or believe how difficult it is to get a metal widget or piece of channel etc made up. Somebody offering such a service would be most welcome, I am sure.

Salut Emmanuel ! Bienvenue.

Je ne parle pas bien Francais - seulement les mots simple.

Mais, nous avons Google translate !

For what it's worth, I very rarely give out my actual phone number on electronic forms, and my email address does not contain an obvious person's name. The number 0123456789 usually is accepted by software as your phone number.

If a delivery company need to contact me they will email me. Nothing is so urgent that they need my actual number - if they can't deliver, they will have to come back another day, that's their job.

Too many times, after I have given my email address to a company or supplier for work related reasons, I get a lot of unsolicited spam. And these are companies who supposedly adhere to the GDPR rules, but clearly their systems are unprotected or riddled with viruses, allowing hackers to trawl their contact lists.

Regarding emails, they are best thought of as an electronic postcard. Any body who handles them can read them. So don't send personal details, photos or data over unencrypted email. One such GDPR company, (above), sent my bank account details back to me in an unencrypted email...........Another, sent my full home address, and this was after I had told them I didn't want to give out my email address but they insisted. A doctor really had a problem understanding why I did not want personal medical data sent over email.

So be very careful with your data, especially anything relating to your identity. Many people and companies who should know better, are very cavalier with sensitive data in emails. Some are just lazy and cannot be bothered sending things via the Royal Mail. Apple iMessage is encrypted, and I believe What'sApp is too, although I do not use the latter.

Edited By John Doe 2 on 01/05/2023 10:51:57

Bituminous panels stuck on all the internal surfaces, then thick carpet stuck onto the bitumen.

Be careful about heat build-up in the box, although it might help if printing nylon for example.

The CAD twist function is fantastic, but why would you need to manufacture this item with a twist - would that be stronger than simply designing it so the shaft with the single eye was kept straight but attached to the U piece 90° further round ?

.......I'll get my coat.

That's a fair comment.

My beef is telling even trained and qualified electronics engineers, that we may not legally work on a control board.

If there is a minor fault on a board, the "Gas" technician puts in a whole new board at enormous cost, when the fault might have only been a £4 relay or a 40p capacitor for example. Fine, the Gas technician does not have the time or the skills and knowledge to fault find a PCB and solder in new components, but those of us who do are prevented by the manufacturers not releasing the information and forcing us to pay huge sums.

My other beef is that in my experience of the last three houses we have owned; the central heating systems have been installed in a very slap-dash way, with very poor pipe runs, in the sense of restricted flow, and components thrown in as quickly as possible, rather than being logically laid out, and no thought given to maintenance of, or replacing components. Floor joists weakened by installers cutting them in the wrong places for pipes. Also the use of push-fit water pipe couplings, which only have a life of around 20 years owing to the O rings failing. Very quick to install but when they start to leak and water comes through your lounge or kitchen ceiling, meaning you have to tear out the plaster board, fix the leak, and then replace, re-plaster and redecorate............

I don't mind paying high prices for good quality, but I object to high prices for terrible quality or terrible work.

I just know that had I been a little old lady with no technical knowledge when our boiler failed; the gas technician would have pretty much forced me to have a new boiler supplied and fitted for about £2,000 because "the old one was beyond repair".......They typically add a 60% surcharge on new items they supply too.

Nope, it is all working beautifully now - much better than when we moved in, and the cost of components was about £85.

In my experience, Bosch have gone right off the boil in recent years. They used to be high quality, but now some of their products are very poor. They seem to have decided to make a down-market, cheaply made range of "toy tools" for the people who think that cheapest means best !

Having said that, I have a couple of good quality Bosch electric drills, and we had a very good Bosch mains lawn mower, can't remember the model number now. You just have to be careful and examine any Bosch product carefully before buying.

When using corded hedge trimmers, put the lead over your shoulder.

When using corded lawn mowers, always place the lead away to the side of the strip you are cutting, never cut walking towards the lead, and constantly look to check where the lead is before moving or changing direction or turning etc.

Edited By John Doe 2 on 26/04/2023 09:41:16

By the way, only move or clean the pots etc with the power switched off - never with the circuit live.

Personally, I doubt that the VFD has gone bang - unless you shorted its output while it was still switched on. It sounds to me that when going through the settings, you accidentally changed a parameter somewhere. For example; output frequency range?

Or disturbed the motor brushes or reassembled the motor incorrectly maybe? Does the shaft spin freely by hand?

Does C101 have a bulging end? Hard to tell. I might also very carefully mark, then gently exercise those five blue pots; "Min Max" etc. It is possible that one of them has a dodgy contact with its track - especially if they might have been damp over time.

Put pairs of dots somewhere on each moving white part and the body with a permanent marker as a reference to get them exactly back to where they were. Probably not too critical.

Edited By John Doe 2 on 24/04/2023 17:07:25

EGO lawnmowers are very good and use 56V batteries. I have two and each one lasts about 30mins

One is in the mower, the other on the charger. When one runs out swap them over and finish the job.

Hint: when using an electric mower try not to stop and start it all the time - spinning up the rotor uses extra power. keep it going constantly where possible.

PS, if your battery does not last, is it really such a problem? Good excuse for a cup of tea !

Well presumably the half round piece stops the piece being drilled from being pushed down under the force of a drill or mill bit?

Making 30-40 larger oil cups with adjustable restrictors would be a much bigger task than routing and cutting thin black plastic pipe - each run of which would only take a minute or so to install. And once installed the pipe system will not need every lube point to be individually checked daily, which I think was part of the brief.

Edited By John Doe 2 on 19/04/2023 09:34:08

+1 for an HGV chassis auto lube system - all the design and development has already been done. Don't know if those systems use grease or oil though.

You might be able to get one from a breakers yard, and rescue all the lube injectors from around the chassis, and then buy a reel of the plastic hose to plumb in your workshop.

Edited By John Doe 2 on 18/04/2023 10:17:36

Looking at the bulb demonstration, that looks very much like a dry joint or bad joint somewhere, as you suspect.

Doesn't seem to be an output stage problem, because the brightness is only varying very slightly - if an output stage was faulty, I would expect the bulb to be going to half brightness or off. i.e. a major difference. What we are seeing seems to be a minor difference, so I suspect a fault in the drive to the output stages, and would look around the speed control area of the board - start with the speed potentiometer itself, it might have a dirty or damaged track.

First thing to do is clean all connections with switch cleaner spray; so any wires held in terminal blocks, or ribbon cables or plugs joining the PCB. Then get some spray into the speed pot and exercise the pot over its full range, backwards and forwards. Allow to fully dry before testing. Then any integrated circuits held in sockets - be extremely careful if you have not removed ICs before, and earth yourself to avoid static discharge. Then resolder the solder side of the whole PCB in case of dry joints.

And then change all the electrolytic capacitors - they can dry out and stop being capacitors, which prevents the circuits they are in from working properly. If none of that helps, you will have to start fault finding the PCB at component level.

Apologies if I am teaching you to suck eggs !

Edited By John Doe 2 on 18/04/2023 10:06:53