Member postings for john fletcher 1

To capnahab, any chance of a copy of the circuit diagram and other information from Dean Smith and Grace here or via a personal message, as it could be very useful to others. I have a good explanation of how the motor connections are give two speeds all from a 1930 electrical magazine. John

Before dismantling the compressor, either replace or have the START capacitor tested. These capacitors are high value AC electrolytic and are only in use on start up, they give the motor more grunt on start up. Once started the motor continues to run on the run capacitor only, the run capacitors are usually very reliable. A friend had a similar but not the same make of compressor and his fault was the unloader valve.John

About twenty years ago I made myself power table feed to my Naerok 350 mill using a car window up/down motor. I made a dog clutch and used some small gear from an old phot copier. Using components from discarded washing machine speed board I made speed control, also fitted a double pole change over switch so that I have forward and reverse and a push button so that I fast traverse. For a power supply you can use a battery charger or make your own. The unit fits on the end of the table and is level with table. In the beginning I used to keep feeling the motor and it hardly got warm. Its still working OK and does a good job. Not all windscreen wiper motors are designed to work in both directions, up/down are so chose carefully.John

I've found that one can easily reconnect a coolant pump into Delta and run it one a single phase supply by connect a 4 micro farad across a pair of terminals and the 240 volt to the vacant terminal and any one of the already used terminals. Also the dust is unpleasant to say the least so coolant improve finish and controls the dust.John

I think the "oil" is in coming form the run capacitor, it's can is leaking. Maybe its time to replace both capacitors, especially if they are awkward to get at. I think the leaky one will be the run one which is in use all the time the motor is running. The other is only in use as the motor accelerates away, it will be high value special AC electrolytic type. The capacitance value will be on the can/container, both are available from RS or Farnell and RS and I'm told RS don't charge for postage, but do check.John

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I have a Super 7 fitted with a very early inverter with no read out, I followed an article in MEW several years back, it works a treat. I can't remember the issue number but no doubt Neil will have it. Since then, the device to which John Stevenson refers to has come on the market so I think I buy one of those, but I get satisfaction on making small electronic gadgets. John.

I made a power feed to my Naerok RDM 350 table top mill using an up down window motor. Unlike some wind screen wiper motor these are designed to go forward and reverse. I made a dog clutch so that I can wind from one end. The power supply is a 12 volt transformer rectifier NO smoothing as I used an ex washing machine Thyristor which requires rough DC. I have a variable resistor for speed control and a double pole change over switch for For/Rev, nearly forgot push button for fast traverse The small gears were ex photo copier.Took me a while to get every thing married together, cost wise maybe £1. That was 20 or more years ago.John

Back again, a book I can recommend is Electronic Devices 4thEd by Thomas L Floyd it's published by prentice Hall and has 960 pages. The comprehensive book take you through basic power supplies to Ic's using test meters and using an oscilloscope, it contains very good coloured illustrations and it shows you typical meter reading or what to expect on the CRO. There are good illustrations of little circuits to make and test, with enough theory for a beginner without being to mathematical on the way. My copy must be 20 years old so you may get a copy via ebay or your local library .Looking in the contents it start with Pn junctions, diodes and their applications ,zenners, transistors, thryristors,triacs,opamps regulators, all very good..John

I will also go along with Dave and Michael, not over excited about the book. There is a lot of useful information on Rod's place, its worth while printing it out for a good read, several times over letting you digest it. Modern electronics ain't what it you to be. I'm Ok with single discreet devices but not with complicated chips. One of the best way is to start making some thing/gadget useful in the workshop, following a circuit diagram from one of the many magazines, then you will learn the resistor colour code, capacitor values and transistors details. There used to be two good magazine one called Electronics International Today, the other Every day Electronics, you may pick up back copies of those two. John

Before you lash out and place an order ,I have a used bet in working order 1 K ohm you can have for the postage, wire wound slightly smaller diameter and you will have to extend the shaft is little. not a big job for some one with a lathe. Send me a PM with your address. John. PS.For any vintage component you may like to join Vintage Radio where you will find some very knowledgeable persons

Still on rust but slightly different.vane. I have a 1950's motor bike petrol tank which was very rusty inside. I put in some paraffin and stainless steel screws shook it around, kept replacing the paraffin until it came out clear. I bought proprietary resin suitable for lining petrol tanks, the leaflet said I might need to apply another product before the resin, but didn't say what or where to obtain the product. A friend suggested the same product plumbers use to flush out heating systems. Suggestions and ideas most welcome.. John

Having the article again, sand paper wasn't mentioned. In the distant past when refurbishing motors which had a "weld spike" on the centrifugal switch we used a needle file to reshape the contacts and polished them up using Crocus paper. I don't think many home workshop will have such a thing, but may have fine wet and dry as used on there cars. John

My friend has a "comeup" DV9000 12 volt battery powered winch. Some one has removed all the very large heavy duty cables and the copper links. The control of the 4.6 hp motor is via two cylindrical solenoids together with a remote controller. I have contacted an agent they site H&S etc so no joy there and nothing on the inter net either.This winch appears to be capable of haul up the beach a small fishing boat, not a trawler. The motor is in as new condition, 4 pole and two sets of brushes and 3 terminals. I would like to know how connect the wiring loom without forcing things. Has any one any knowledge of this winch, if so please contact me.John

To SillyoldDuffer. If you venture onto Vintage Radio forum you will find out your AVO is a relatively new one, plenty of pre 1939 one available and plenty made during WW 11. They were made for all the armed forces. My AVO test Bridge was made in February 1944 and still going strong. To identify the date of manufacture look on the top right of the scale and you will see the code, in my case 2-44.John

Regarding the lawn mower which wouldn't run, could it be a two stroke engine. 50 or more years ago we had a lawn mower with a Villiers two stroke engine which wouldn't start. Dad replace the points and condenser. Now called a capacitor, as he though the spark was weak. He had the cylinder block re bored, still it wouldn't run. Some time later a friend called round and said is the silencer blocked and when dad removed the silencer it was almost solid. One kick and the engine fired up. It took a lot of ingenuity to remove all the carbon.John

Rusty petrol tank. I have a petrol tank of about 1 gallon capacity as fitted to 1950's two strokes which was very rusty inside, I put some paraffin in the tank and stainless steel screws and shook the lot around for maybe an hour, that was two years ago. I recently bought some resin petrol tank sealer and it says give the tank a pre sealer application of what ?? . A friend suggested the same substance which plumbers use to flush out heating systems. Comments and idea most welcome.John

Well I had a strange experience, phone rang the caller said he was the tax inspector,and said I was due for tax refund. Would I like my tax code adjusted or would I prefer a cheque, I thought he was joking, anyway he convinced me he was genuine, so I said what about the interest, he said that would be calculated and that it would be added.I opted for a cheque as I thought the Venture Capitalist would soon send the country bankrupt, a short time later a cheque arrived. Poor old tax employees often get ridiculed, but I'm pleased to say they do good job under adverse conditions. For those moaners try living in a tax free country and see what the locals have to put up with .John

There is a short very informative video on youtbe on setting up Huanyang VFD. My friend bought one on ebay £90.40 and it's very good, easy to set up and the deliver was so quick. How do they do it ?. I have an elderly Yaskawa VS mini series VFD and would like advice on altering the settings, it is running at the moment. I have what I think is the important part of the manual, but some of the settings don't register with me.John

Be careful which wind screen wiper motor you buy, as not all are designed to be reversed. An down window wiper motor is more than adequate and all are designed to go up and down. David Machin did an article in an early MEW on such a project, he included a circuit diagram of a speed controller which is very easy to construct. John

Reconnect the motor into Delta, often by moving the brass links. Being dual voltage your motor will have 6 terminals, one group of 3 will be linked together, move those links so that they will each link each row front to rear not along. All that is often on a label within the terminal box. Then you will need several MOTOR RUN capacitors if you are to run the motor that way. Obtain two contactors each fitted with a 240 volt operating coil and a bunch of old fluorescent light fitting capacitors. You need two groups of capacitors each group controlled by its own contactor . One group is the run group the other, which is start group, both are connected in parallel for start up . Once the motor is up and running the start group are disconnected. With a LOT of CARE this is not difficult to achieve and it works well. The down side is getting the current in each phase equal to the next,some careful adjustment is required. I made a sheet steel chassis to fit into a large metal box I already had. I then mounted every thing on the chassis. I had a RED and GREEN pushes mounted on the box. The sequence of operation, press the green button and count 3, both contactor will be energised. On releasing the button the start one drops out and so its capacitors are disconnected, the run one continues to be energised.Motor purrs away.I f you need any more details send me a PM. John