Here is a list of all the postings An Other has made in our forums. Click on a thread name to jump to the thread.
|Thread: Which Laptop|
I had an Advent machine, running much the same software as you, but had to replace it because the screen failed (odd lines across the screen). I had used it for a long time, and it made more sense to change it than repair it.
Eventually, I bought an ASUS Vivobook. There are several models of this machine, at varying prices (lot seems to depend on where you buy it). Mine has a 512GB SSD, Intel I3. It is so much faster than the old Advent, which seemed attributable to the SSD, that I subsequently updated my 2 tower machines to make their boot drives SSDs, which confirmed that the SSDs booted very fast. The Vivobook with Mint is about 20 seconds max. I have no CD/DVD drive, but I believe some models are fitted with them.
The screen is comfortable to use - some reviews claim it has a narrow viewing angle - from my experience, I would say the reviewers had a narrow viewing angle, not the display. Good range of brightness/contrast, and easily adjustable, and colour acceptable.
I run the latest Linux Mint 20.1, with much of the software you are using (except I use VirtualBox instead of Wine). I do quite a lot of CPP and some RUST programming work, so I also have the required tools for that. I have never had any problems installing or running Linux Mint on this machine (or the Advent, come to that)
It is a vast improvement over the old machine in terms of speed, and also has a much improved keyboard (important when you sit key-bashing all day) - The old Advent used to get hot - working with it balanced on my knees was sometimes quite painful, but the Vivobook appears to run much cooler. As always, battery life depends on what you do with the machine, but I have no reason to complain. In fact, possibly the only 'complaint' I have is that the power unit makes an odd sound like an ambulance siren in the distance - I suspect it is a buck PSU, and when the battery is charged, it is switching on and off - very faint, but I can just hear it - no problems otherwise.
|Thread: help needed|
The incoming cable to the house often has 2 pairs of wires, but as several people have noted, only one pair is normally used. The easiest way I know to identify the correct pair is to simply find the two wires with a DC voltage across them - can be anything between 20 to 30 Volts DC. These are the two you should be using.
If you have a junction box, then simply connect the two incoming wires to two of the wires in the dropwire,which should go to the socket in the house. (usually the a/b pair). The other wires can be tucked out of the way and ignored.
We actually have a 20-pair cable coming onto our property (if I counted right), and I had to locate the correct pair when I re-routed my on-property connection - this worked for me.
|Thread: Non-renewable energy|
Some interesting figures, and for sure something will have to change, but just to put it in perspective:
Where we live, almost everyone uses wood to heat their houses and for water - I'm not talking about 'our village' - I'm referring to the entire country. Most of the wood is from ancient oak and ash forest, which cover large areas of the country, but are being cut at a tremendous rate by illegal loggers. Much of it is taken out of the country, in particular to Austria and Hungary.
The wood is not even burnt in efficient stoves, (if such things exist) - many people only have simple home-built brick and ceramic stoves. I have no idea how much pollution and carbon dioxide this produces - our government does not publish any figures.
Many villages don't have piped drinking water (ours is one) - we are lucky and have a borehole for water, but many people have a hole to collect surface water - not a well into the water table, but a simple hole collecting rainwater or surface water.
Nuclear power would be a dream, but the electricity mostly comes from coal burning power stations.
|Thread: Wood boat hull|
Why not have a browse around the Model Boats site for some ideas and inspiration - go to the ME home page, and scroll right down to the bottom, the link is in the gray box.
|Thread: The Raspberry Pi gets domesticated|
|Thread: Looking for recomendations.|
I was going to reply to the last post - but there really seems no point.
So far you only seem to have concentrated on the motor, and you seem to have confirmed that it is OK. You can test the control board by connecting a 100W filament type light bulb in place of the motor. When you you turn the speed control, the brilliance should change. If it remains at full brilliance, or is off, then the chances are that the output devices on the control board are defective (I call them devices, because no-one on this forum, as usual, seems to agree what they are - to me, they are power MOSFETS. On most of the FC250 boards I have repaired they have been either 2SK790's or IRLZ44N. The 2SK790 seems to be fitted to older boards, and the IRLZ44N to the newer boards - they can still be obtained. I am not sure which devices(s) are used on the board you have - there are many versions of these controllers, but in general the output devices have been the same whatever the board.
|Thread: Mini Lathe|
Godfrey - PM sent.
|Thread: Awstin or Ostin|
When we lived near Oxford many years ago (large BL factory), we all called them 'Rustins'
On that note, I always thought at the time that the Wover 2000 bonnets were made of aluminium, but I can clearly remember seeing hundreds of them stacked on end in the Pressed Steel Fisher yard, and every one was a beautiful delicate shade of reddish orange. At first we thought it was paint or some sort of treatment, but close up, it was a nice smooth coat of surface rust.
|Thread: Burgess BK3 MK2 capacitor|
+1 for NDIY - so long as the working voltage is high enough, it should be OK - assuming it is running on 230 VAC mains.
Capacitor value is a little more sticky - I took a quick look at some of my motors, and the capacitors seem to vary from 4uF up to 25uF, with no relation to motor size. I had to change a 1/2 HP pump motor capacitor that was unmarked, and simply fitted a 12.5uF one that I had available - the pump motor has been running for months now with no problems, so I would take the plunge and simply fit something like 5 or 10uF, and see what happens. If the motor runs smoothly and doesn't overheat - problem solved. These capacitors are by no means 'precise' in value.
Nigel has 4uF - as good a guess as any.
Edited By An Other on 18/09/2020 10:31:42
Bit confused - I guess I will be shot down in flames by one of the many experts in this forum, but I don't understand what you mean by mu factor. Do you mean the value of the capacitor in microFarads? The symbol commonly used for micro is the Greek mu.
|Thread: Mini lathe blown fuses and Motor overheating|
This seems to have wandered away from Davids Lathe Problem -
Just to re-iterate for Davids sake: The control board is a Pulse Width Modulation controller and DC power supply, providing something like 200VDC. The DC supply powers the motor, and is switched by the controller - varying pulse width controls the motor speed.
As mentioned by other members, the motor can be tested by connecting across a 12V car battery - it should turn fairly slowly - if it does, chances are it is OK.
Also as mentioned, the controller board can be tested with a 100 Watt incandescent filament bulb - connect it in place of the motor, and it should be possible to vary its brilliance using the motor speed potentiometer. If its on Full, and uncontrollable, chances are the output devices (there are various types) on the controller board are short - circuit - this is a common fault, but can be repaired relatively inexpensively with the appropriate skills. The alternative is a replacement board at about 120 Pounds. Arc Euro Trade is a good source (no connection) for spare boards and motors - look at their web-site.
Hope this helps a bit, David
|Thread: Home made cast Aluminium|
I've done lots of home ali casting, usually on the 'lost foam' principle using hard insulating foam (open cell packing foam is useless). The casting part is relatively easy, if you take care - (don't wear sandals ). I was advised to heat until it was thoroughly molten, scrape off as much dross as possible, then leave it to stand for a few moments before pouring to allow air to rise and disperse. This has worked well for me, and I have cast many bits and pieces, for example for a sanding disk machine, and for electric motor mounts. I have experimented with sand casting, but found it virtually impossible to get the various additives needed, despite many self-proclaimed experts telling me to use cat litter and so on.
As well as parts, I also cast slugs of ali to use for turning - usually OK, but do expect to find some blowholes sometimes, or very small pin-holes in the metal. There are many 'folk-lore' stories of what can be used as flux to help prevent this - most never seem to work, so the best way is to try it yourself. If it doesn't work, you can always remelt the ali and try again.
I used all sorts of stuff as raw material - cans are useless, they will burn to dross. Try old car engine bits, such as cylinder heads or pistons. My scrapyard lets me have them just for the scrap-metal weight.
Biggest 'don't' is don't spill the hot metal - it spits like hell on earth or cement - work on a sandbed is best.
There are many websites providing info, such as furnace builds and burners - mine is a stainless steel bread bin lined with a mix of fire-cement and some clay I found - works fine. The burner is home made according to J Reils ideas, and works equally well on Propane or (more slowly) on Butane (Propane is hard to get where I live).
|Thread: Who trains these ideots?|
Hi, Circlip (Ian)
Don't know about the various Harry Potter accessories, but I PMed you with a method how to cancel the Service Warning. I know there are several methods used, depending on the model/year. I think I have sent you the Sandero method, but let me know if not, and I'll try again.
There is nothing new in the world, I guess, and there have always been incompetent tradesman in all disciplines, but I'd like to play devils advocate for a while...
There is no excuse for a plumber advising buying a new, expensive boiler without even taking a look at the old one, but he is hardly responsible for the price: he hasn't made it, it has come from some manufacturing company somewhere, who supplies the plumber. True, he probably added his markup, but if the price is high anyway....
I mention this because I had a good friend who was a plumber all his life (and did an apprenticeship). His favourite moan was 'bl**dy customers'. As he said, his job was not an 8 to 5 thing - it was 24 hours, 7 days a week, public holidays included. It wasn't difficult to imagine a customer panicking when a leak developed late at night and calling the plumber, but as my mate said '...and I'd just got home after a 12 hour day' - the customer doesn't see it from the other side of the fence. He said he tried to help the customer if he could, and would often turn out late at night, or on a weekend, but often there was little he could do. Many times he complained about going to an emergency, finding (for example) a leak, then having to do several hours work to locate and close a rusted stop-valve. He said he had even found in some case the idiot home-owner had covered the valve with 'renovations' or 'updates'. Of course, as he said, he could just go home and leave it - not his problem if the house-owner was a fool, but he claimed he rarely did that.
He used to describe one call to find a leak, where he found a hole through a pipe: the customer had found it, apparently, prised up the floorboard, and taped up the leak using plastic electricians tape, then replaced the floorboard. Of course, it was only a matter of time before the leak started again. When my friend got there, the householder denied all knowledge of it, until it was located. When challenged, he finally admitted finding the nail he had driven through the pipe - and thats the plumbers fault???
And as he also pointed out - 'my wife isn't a plumber, so what do I tell her about working all hours, and having no home life'?
Of course, times have changed, but all my life I can remember people whinging about the incompetence of workmen. I don't believe they have changed that much - I think what has changed is peoples tolerance and understanding - everything has to be done now, for as low a cost as possible, with no regard to anyone or anything else.
Edited By An Other on 19/08/2020 12:01:58
Bit 'Off-Thread", but a bit of info for Circlip regarding his Sandero. I have had two new Dusters (last two models) with the same problem - up comes a warning with a very low mileage that "Service is Due'. Off to the garage, where I am told I must pay for an oil change, plug change + all filters changed - at less than 2000 kms. No use complaining, if I don't do it, then the guarantee may be 'affected'.
So the first time I paid up. A few hours online later, I found out that a simple keypress combination on the dashboard, or in some cases, pressing the pedals in a certain sequence, will reset the warning - and the garage is none the wiser - there is almost certainly a keypress solution for the Sandero similar to the Duster, since all Dacia cars have common design features. (I live in Romania, where these cars originated, and it is a well known issue here).
This design feature is a particularly bad move by Dacia Renault.
|Thread: Arduino Gear Hobber|
Very interesting thread - since Arduino is 'open-source', many companies market copies and developments. One such is Redboard (US I think), and they market an Arduino UNO compatible board which runs at 48 MHz (3X faster clock than the standard 16MHz UNO) - it can be programmed using the familiar Arduino IDE.
Redboard stuff seems to be marketed fairly widely. I haven't done the calculations, but this may be useful to those familiar with Arduinos, and get round the speed problems. (no connection with Arduino or Redboard).
|Thread: A beginners locomotive|
Sorry to put this here, folks - Del - can you contact me re drawings? - your inbox is full.
|Thread: Minilathe/Mill motors|
Thanks for the inputs - given me something to think about - just a few comments:
I have seen the operating voltage of these motors mentioned in many places, and frankly they seem totally contradictory - some sources say as low as 80VDC, others 120VDC, and yet others up to the 180VDC mentioned here by Pat, who also notes the boards are different. This may be the case, but as I said in my first post, the power supply for the motors is the same.
I know they use PWM for speed control, and that simply limiting the on/off ratio of the pulse would limit the average voltage to the motors, but as I said, I have the circuits, and the ones I have (UK and US) show no difference in the PWM control circuitry itself. There is a current feedback loop, which has a different sensing resistor for Europe (0.33 ohm) and for US (0.22 ohm) - and a startup compensation loop, which appears identical in both cases. So I agree with Andrew, and also with his comment that anything goes.
Roberts explanation is interesting - it also seems to explain why the European version suffers from damaged motors (I have three, all with internal shorts or open circuit (in the windings unfortunately). I appreciate the explanation of improved versions, but I want to remain with the existing system if possible - I have various spares, and a fixed pension
Joseph - I don't have the means to scan the circuits at the moment (and its a damn nuisance!), but I also have worked in electronics for many years, and can tell you the motor supply is definitely NOT run as a doubler. It has L&N connected to the inputs of a bridge (an S4VB as marked - also risky - its only rated at 4 amps). The positive output goes directly to the motor via the current sense resistor mentioned above (and a relay contact). The other side of the motor goes via the 2 parallel IGFTs to the negative rail. There are no large capacitors anywhere - none at all in the motor power supply - its a raw full-wave rectified supply.
The PWM switching IGFTS are switched by the PWM signal fed via two optoisolators to the IGFT gates. (I think one optoisolator turns the IGFTs on, and the other is used to speed up the turn-off - they are definitely NOT connected in parallel, or one to each IGFT). The 18V power for these IGFTs is also derived from the raw motor supply - just an R/C/Zener supply.
So as you see, a very simple circuit. It was the apparent lack of any obvious or failsafe method of limiting current through the motor/IGFT chain that prompted my question. Most of the failures I have had were shorts in the IGFTs, leading to the motors running flat-out with no speed control, or burned out motors - and now I am getting a better idea why. The IRFP450 has a continuous drain current of 14 amps, but its power dissipation is only 180Wmax. I believe the motor is rated at 3A (I stand to be corrected), so if a European motor is run at 180 volts, the power is going to be possibly over 500W (3 x180), which cannot be correct if the motors are rated at 250W, or even the newer 350 Watts - this suggests either a lower average operating voltage, or a higher current rating. It also accounts for the two IGFTs in parallel. It is not difficult to see that a stall condition could lead to high current, followed by IGFT failure, followed by motor failure - hence my questions about the motors.
Dave - you are quite right - I have a circuit for a motor controller which has the configuration you describe: the XMT 2335 fitted to Sieg C3 machines has this configuration - but as I noted above - I need to stay with the original configuration. The bridge rectifier in the FCXXJ series is just a simple silicon bridge - an S4VM in my case. I have seen a board with separate diodes fitted in place of the bridge.
Many thanks for the inputs - I'll go away and see what I can modify. (Been considering using an Arduino UNO to generate the PWM control, but its still a work in progress until I am happy with the motor power side.).
Edited By An Other on 28/03/2020 18:58:06
I have had a 7x12 'chinese' lathe and mill (X1 type) for many years now, and have had the usual trials of failing control boards and motors several times. I know there are many different motors/controllers fitted to these machines, but I refer to the older versions (I think 250W or 350W brushed motor)
While fixing these problems, I have collected various circuit diagrams and info relating to these machines, and as a result have a question:
The circuits for the European and American controller boards (for the lathe, for example) are very similar ( number is FC250J, but the same question probably applies to the uprated FC350J).
The DC voltage for the motor in these circuits is derived from a bridge connected directly to the incoming AC Mains - so in Europe this should be 230 x root(2) = 325 volts DC, and in America 120*root(2) = 170 volts DC. (I think).
There are some differences in resistor values in the control circuits from the two areas, presumably to compensate for this difference in voltage, but there appears to be no difference in the bridge DC supply for the motors, implying that a much higher voltage is fed to the European version. The drive circuit (via two IRFP450 IGFTs) is apparently identical in all the circuits I have.
Does anyone know if a different motor is fitted in the two areas? There seems to be no indication on the motors themselves. I ask because I think one of the motors I have came from the States, and I would like to use it.
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