Member postings for AdrianR

All depending how much of the board is missing and what the circuit is, but you can just use thin wires soldered on to replace the missing parts. Solderable enamelled wire is an easy way to go, as the enamel comes off with the soldering iron and flux. No stripping needed. Tack it to the board with super glue or hot melt.

Also there are pcb repair pens that use a silver loaded glue, all you have to do is draw the new track.

Only time this could be a problem is if the board is carrying high frequencies where the board itself becomes part of the circuit due to its inductance and capacitance.

Of course it does not work so well for multi layer boards, I assume yours is either single or double sided, not a multi-layer one.

Edited By AdrianR on 14/08/2019 14:13:33

Dont let it get too hot and then quench, the sudden cooling can cause micro cracks that weaken the tool. So if you are quenching, quench often before it gets too hot.

The skin effect is true, but applies to each conductor, so a multi stranded cable has more surface area and therefor has lower resistance at high frequencies.

Audiophile speaker cable has multiple very fine strands for this reason. Even better if it is gold plated.

Incidentally on a different subject, If you have ever wondered why power lines have more than one cable on each arm it is to combat the corona effect. This effect is where electrons gather at sharp points, e.g. sparks start at the point of things. A high voltage cable in cross section looks like a point, so will bleed electrons into the surrounding air. By having more than one cable closely spaced they tend to cancel the electrostatic field. This means to the electrons they look like much fatter (blunter points) cables.

Adrian

I do believe that unless the clock was three phase this is an Old Wifes Marts tale!

Opps, I expect it is Ofgen that worry more about the mains supply than Ofcom. Maybe I should get all my posts checked by Ofof before posting.

Hi Tony,

Unless that is a throw away phone or you like scammers etc. I would not publish it's number on the internet.

Either delete the post or ask Neil or one of the other moderators to delete it. You can send private messages to members using Message Member under their post.

If you have added the photos to an album you can insert them into posts using the camera icon on the edit box. They will then be shown inline in the post.

I just looked at all your pictures, looks like a good idea, could be a perfect use for the worn out old ML2 I inherited. I wonder if it would be possible to do the side flutes on the lathe too. Mount the cutter between centres, Fix the finger to the cross slide, dremel to top slide, then move the saddle to grind the flute.

Adrian

Edited By AdrianR on 13/08/2019 13:03:28

The news story is correct, mains frequency is important.

This is one of those counter intuitive things and is all to do with AC power theory.

Generators are basically synchronous motors that are driven rather than driving. If you don't know what a synchronous motor is see here

The important thing to know about synchronous motors/generators is in the name, they are synchronous with the mains frequency. That is with no load they run with the rotor spinning so that the rotor and stator magnetic fields coincide. N-S, S-N

As a motor is loaded, the angle between the rotor field and the rotating stator field increases and the rotor lags behind the stator field, so it is dragged along by the magnetic field. As the fields are not aligned, part of the stators field is cancelled by the the rotors other pole. ie A North stator sees mostly a South rotor pole plus a little bit of North rotor pole, and the magnetic circuit is slightly blocked. To keep it simple, less magnetic field, the more current flows in the stator, so more power is consumed and this power is converted into torque.

As the load increases eventually the rotor and stator break out of synchronisation and the motor stalls.

Now if we take the same motor but start to drive the shaft around., then the rotor will start to lead the stator field and the process is reversed. The torque is converted into power transferred to the grid, the amount generated is proportional to the difference between the grid frequency and the rotational frequency.

As you drive the shaft harder and harder, eventually the synchronisation will be lost and very nasty things possibly involving bright flashes and smoke happen. This is why they have automatic trips that drop out when the supply is out of tolerance and they say "it is to protect the rest of the system"

When more power is added to the grid with each generator leading the grid slightly, it has the tendency to increase the frequency. As more power is taken from the grid the reverse happens and the frequency drops.

To ensure the grid stays in balance we use 50Hz as the target frequency, each generator is synchronous and running with a leading angle so that the most efficient power transfer happens.

There is also a link between voltage generated and frequence, the higher the frequency (rotational speed) the higher the voltage. So at 50Hkz we will end up with the correct voltage on the grid.

As there is no way to store power in the grid and the load is varying, we have tolerances on the frequency and voltage. The national grid predict what power is needed at any time, and ensure generators come on and go off line to meet the load. However we have transitory loads, i.e. Advert breaks on the TV, every rushes out and puts the kettle on. Most of those are adsorbed in the tolerances, but some times it is necessary to increase the frequency just before a big spike, say an advert break in Coronation Street Xmas cliffhanger special.

So you can see Ofcom are correct in getting a little upset that the frequency has been bouncing around near the lower limit. It means the grid is running close to collapse. The loss of those two power sources resulted in the automatic protection tripping and the power cuts. If parts of the grid were not turned off we would have a cascade failure. Every power station in rapid sequence would drop off the grid as the remaining load was spread across fewer and fewer power stations.

The switch to wind an solar only make the situation worse, too much or too little wind and night time all mean the power going into the grid is reduced. So we need other sources, at the moment that is gas powered, eventually it will have to be battery storage. Nuclear is OK for base load, but it takes a while to warm up and cool down a reactor so it cant be used for transients.

We are already short of generating capacity, add in electric cars and houses switching to electric heating and we have a very real electricity crisis looming.

Adrian

It will be worth more if you can find the missing blocks.

You can advertise in the classifieds on this site, or there are people who clear whole workshops. All depends how much effort you want to put in.

Would be good if you can list a few more of the larger parts and/or take photos. Even a photo of the workshop would give us a better idea of what sort of tools you are talking about.

Adrian

Those symbols look so familiar, I am sure I have seen them before, just cant remember where.

I have looked through astrology and elements none of those, very frustrating.

Adrian

This is quite a good breakdown of how it works YouTube

Well today my rural broadband is really bad, my normal 2.5Mb over the last week or so has dropped to 1Mb.

Even talktalk's online tester says it is not working right, but I really could not be bothered to contact talktalk's customer services so went to look at switching to Zen.

Zen checker said I could get fibre, so I checked BT, it also says fibre, oddly talktalk says adsl.

I just rang Zen to double check, they are sure I can get fibre so I have just signed up. The monthly fibre price is the same as my current adsl broadband.

Looks like the villages fibre cabinet has been provisioned and no one has been told.

Adrian

Might I suggest you post pictures of your tool holder so the myford guys can tell you if it is the right type for your lathe.

Also this video is very good and explains how to set tool heights **LINK**

I clean up with a file, it is not a waste of time as it means I don't have to do it when I cut the next bit. Plus of course I like my blood on the inside of my body. I leave enough of it around the workshop as is, without adding to it.

Oh and there is far worse than a cut, darn metal splinters. Always hurt, always jagged like harpoons so have to be dug out and always seem to get infected.

Adrian

Yeup, the 50% was for deep discharge batteries. Yes you can discharge them more but it drastically reduces their lifetime. 50% is a compromise between capacity and lifetime.

I note that one of those electric lawn mowers has a 3yr warranty and a 1yr limited warranty on the battery. What a confident manufacturer.

I think the conversion to an electric motor is easy, the hard bit is getting the batteries.

The energy density of batteries is very low compared to fuel and to have a decent run time you need huge batteries. Which if are lead acid are also very heavy.

Your 12HP engine would need to be replaced with a motor would draw 11KW assuming 80% efficiency of the controllers etc. At 48V that would be 229A, so for 1hr at full power you would need about 500AH of battery (lead acid max discharge 50%).

If you want to be green, buy biofuel.

I live in rural Lincolnshire, 2 years ago OpenReach installed the fibre cabinets, still waiting for them to be connected. Useless bunch of ....

I am on TalkTalk, customer support is a not great, but no worse than others I have used. Reason I went with them is they were the cheapest, so why pay more for the same product from others.

The one exception to that was Zen, customer service was great and the contention was low.

I am approx 6 miles from the exchange, and the TalkTalk router gives about 1.5Mb/s. I bought a Billion router and now get 2.6Mb/s

I would say the OP should just stick with ADSL, fibre is really only of use to customers who are further away from the exchange. Fibre is just a way of extending the exchange termination so it is closer to the customer, no magic.

The only possible reason to switch would be to get a lower price, but you really have to inspect the cost after the contract period.

Adrian

Yeup, it is for oiling the pulley spindle.

The best manual for our lathes is from Grizzly for the G9249 it is how a manual should be for a £2500 lathe.

Hi,

I find the videos made by Joe Pieczynski well worth watching. Lots of information about using the Mill and Lathe. Well worth subscribing.

Adrian

This is a good video about parting tools, **LINK**

I find all Joe's videos worth watching

Here is an image of my Warco BH600G which is the same as the Craftsman.

As you say the drive comes in on the pulley which is free to rotate on the spindle. The small gear to the left of the pulley is attached to the pulley. The small gear drives the large back gear which is fixed to the lay shaft. The lay shaft drives the small back gear which is engaged with the spindle bull wheel. The bull wheel is fixed to the spindle.

Hope that helps,

Adrian

Edited By AdrianR on 30/07/2019 14:15:28