Member postings for john fletcher 1

Vacuum cleaners are the carpet manufacturers best friend, the more powerful the suction the more they like them. Have a look at the cylinder of a Dyson and see just how much fabric is in the cylinder when its full. I think we are obsessed about the need to clean our homes, with all the chemicals and sprays around Gramma never needed them and she lived to a good old age and rarely visited a doctor. Also I notice that in the US and Canada and some European countries they have cold water detergents for use in washing machine, not the UK why? Ted

The start winding will have the highest resistance, much higher than the run winding which should be around 4 ohms. As some one has already stated, the start winding, the capacitor, together with the centrifugal switch form a series winding, which are then connected in parallel with run winding. Once the motor is up and running the centrifugal switch opens, leaving just the run winding connected to the mains electricity. If the capacitor is connected to terminals Z & S Ok, As I see from your picture(photo) one side of the centrifugal switch is also connected to terminal S OK there. So, from terminal S to the lower Lucar connection on the Bakelite centrifugal switch board, through the switch, checking that the contacts are clean and that they do close up, then to the upper Lucar connection, that forms the start circuit. At this stage you should, using a multi meter on the ohms range, be able to measure the start winding circuit resistance. Its not easy to test the capacitor as they are special AC electrolytic, not the ordinary paper type although they will be OK.

It would appear that you need two short links one between Z & AZ, the other between A & T. The mains is connected to A & AZ either way round. To reverse the motor move T to AZ and Z to A. The most important wire is the EARTH. SO ENSURE YOU HAVE A GOOD CLEAN EARTH CONNECTION, and if your motor is mounted on resilient rubber mounts check there is a link between the base mounting plate and the motor the motor casing. Let me know how you get on.Ted

I have done this quite a few times. As stated, it the capacitor value you have to juggle around with.

You need a large capacitor value to get the motor up to speed, I use two distinctive groups ,in parallel for starting, then one group (the start group larger in value ) is disconnected, leaving the smaller group (the run group) in circuit. I use two contactors to do the switching. Pressing the start push, count five or pause brings in both contactors and connects both lots of capacitors to the mains and the motor, then release the push and the motor runs. The contactors are so wired as to give no volt release should there be a mains failure and there is a local stop push. Ex fluorescent light capacitors are OK for this application as are ex power factor correction capacitors. Please be extra cautious when handling capacitors of this quality, they can store charge of energy for a time if not fitted with a discharge resistor. I suggest you switch off, wait a while, then short out the terminal of the capacitors with an old screw driver before working on or connecting them. Belts and braces. For coolant pumps I found one small capacitor to be enough as it starts off load in effect. Actually it best to test all three phases with a volt meter and that way one can adjust the capacitor value to get near balance, also put your hand on the motor after its been running for a while, bearing in mind that modern motors run very hot. Ted

Back again, I forgot to mention have you tested the diodes, could be one or more are short circuited, which not unknown.Ted

Regarding the wire wound resistor, it may be possible to connect the two broken ends together then measure the resistance with an ohmmeter to establish some idea of its original value, then obtain a replacement from RS or Farnell. As stated, it maybe some sort of soft start resistor in series with the transformer input to limit the initial inrush current to the diodes. The two large capacitors would initially, for a brief moment in time, take very large charging current. That inrush current could blow the rectifier diodes unless limited, it does happen.. Also have you contact the manufacturer or even the Polish commercial section of their Embassy in UK. I once did (not Polish Embassy) and was pleasantly surprised by the reply, very helpful. Ted

We did a tour of Kerala and Tamil Nadir in a Ambassador fitted with a Nissan diesel engine and dynamo, the taxi driver topped up the radiator at every possible opportunity. We "negotiated" as you do in India, with a taxi driver ( a grand chap) who spoke little English, he didn't have a map or knew how to read one, he relied on us. The engine struggle up in the mountains but go there, had a great time in spite of the engine noise. Flew in to Trivandrum £300 each return. We can recommend South West India, wonderful scenery, beaches and food. Ted

Not in the summer, but make my own battery powered loco speed controllers during the cold winter months. I would like to link up with others who do the same, to possible exchange ideas.

There is an ALLEN screw in the hub (axle) on the wheel nearest you when operating the saw. This screw needs adjustment to alter the tracking on that wheel, then every thing should be OK. I have the details some where but I've put it safe and can't find it. I seem to remember that you have to slacken the large nut which is in the centre, then tweak the ALLEN screw which is on the inside just a little bit. I'll get back to you later today.Ted

Hello Ian and other readers, you say you connected two low ESR capacitors across the terminals, what type of capacitors and what were the values please. I'm thinking of fitting DRO to my mill and that information would save time and avoid frustration to know how others have over come problems.Ted

If you need a copy of the wiring I have one and can send you to you but I would need an address. I'm not very good on the computer but might be able to get my neighbour to send you an attachment but would need your email details. There was quite a discussion on here some time ago about the Tri-lever so you might be able to locate it.Ted

To eliminate the possibility of a faulty capacitor simply disconnect the capacitor altogether and put a piece of wire in its place, the motor should run. Your local motor re winder will have a replacement capacitor should you need one or maybe a member of the local club will have a spare hanging about doing nothing. I seem to remember all sorts of dangerous practices taking place in the 1950/60 from people who should have known better, good sense now prevails in most cases.Ted

Dewhurst switches are not really up to the job as Eric has said, they should be used in conjunction with a direct on line starter which has overloads and no volt release. The Dewhurst should be used for altering the direction of rotation of the motor only. Select D.O.R of the motor then press the GREEN button. There are spare un used contacts on a Dewhurst which you may be able to utilise as replacements. Note how the links are positioned before dismantling, but how often do you or me want to run your lathe in reverse. If you have much trouble you may wish to consider obtaining a 3 phase motor and inverter, there are plenty of pre owned ones around, no need to buy an expensive new one. Like there are plenty of pre owned starter available .Ted

I have a Vertex rotary table bought about 20 years ago. I soon modified the spring loaded handle for the same reasons others have mentioned. Before removing the handle from the rotary table I marked the plunger shaft in two positions. 1, when it was in location position (fully extended into a hole). 2, when it was fully clear of the dividing plate and scissors legs. I then removed the handle and dismantled it, carefully driving out the pin at the end of the knurled handle, as I intended to use the pin again. This released the spring loaded plunger and clearly exposed the marks which I had previously made. I next drilled a hole on the mark towards the end from where I had removed the pin and tapped it 3mm. I mounted the knurled handle in the milling a machine and made two 3mm longitude slots in it, about 90˚ from one another. One slot long enough for the sprung loaded plunger to fully enter a plate hole, the other to restrict the plunger so that when rotating the handle the plunger pin is clear of the scissor legs. When I re assembled the handle I screwed in a 3mm cap head allen screw into the tapped hole and its worked well over the years. In use I pull out the knurl handle against spring tension and twist it one way or the other left for fully in. right for clearance

I haven’t a photo but hope my description is understandable.Ted

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I f the motor has a commutator and is fitted with carbon brushes then the capacitors, as others have said, are for interference suppression and the motor should run with out them, for test perposes only !. The capacitors should be X type as the adverts says.Ted

Hello Ian and others. Before spending any money try Julians idea, but be very careful.Wrap a piece of string around the motor pulley give it a good pull and then switch on the power.This way you are eliminating the start circuit,as the weak parts are the start capacitor and the centrifugal switch. I have replaced start capacitors with ones with a higher working voltage 400 volts, the original ones were 240 volt and I haven't had any come back.I'm not familiar with your lathe or motor but the next thing is to get an electrician with his Megger to carry out an insulation test both between winding and to earth.Not often do you get a short between windings or open circuit. I have had several Chinese motors to pieces and they are well designed and well constructed, inspite of what the advert says in Model Engineer,but having aluminum cooling fins around their outer can be a bit noisy, ringing sound. One good thing is you only have to take the drive end off to gain access to the switch and the windings, very easy to dismantle and re assemble.I'm not in business fixing motors, but help out my friends as and when they need it.Keep us posted.Ted

Why not look in back numbers of MEW and make your self several Eccentric type tool holders, together with the grinding jig. Then it is so easy to grind lathe tools.Cheap, cheerful and they work.Ted

I suggest you get a copy of each of the following, "Workshop Technology" author W A J Chapman, Publisher Arnold parts 1 & 2 only.First published in 1942 when I was a lad.I don't know if there is modern version but these books are very good. To stimulate your brain when not in the workshop you might also like a copy of his "Applied Workshop Calculations" and use Log tables to anwers the problems. Also very good are the EITB manual given out to the lads on the training board courses in the 1960's/70's.You might get the books on Amazon.Ted

To help Chris along, has a reader got a copy of the lathe circuit diagram and who can publish it here, which will help. Chris have you a tradesman friend with a YELLOW 110 volt power tool transformer? If you have, then you can disconnect your 110 volt one and feed the circuit via your friends, which will eliminate the transformer. Alternatively if you have a friend with a MEGGER he will be able to test your transformer in situ. The same friend could check out the motor for earth faults. I’m not familiar with your lathe Chris, what electronic controls does it have? TedTo help Chris along, has a reader got a copy of the lathe circuit diagram and who can publish it here, which will help. Chris have you a tradesman friend with a YELLOW 110 volt power tool transformer? If you have, then you can disconnect your 110 volt one and feed the circuit via your friends, which will eliminate the transformer. Alternatively if you have a friend with a MEGGER he will be able to test your transformer in situ. The same friend could check out the motor for earth faults. I’m not familiar with your lathe Chris, what electronic controls does it have? Ted

Edited By John Stevenson on 12/03/2014 21:53:21

Back again Alister re your lathe bed. Colin sent me the following.http//gb.kompass.com/c/robert-skinner/gb92053664.I hope you uinderstand all that as I'm no expert on the computer.Ted

A friend of mine recently had two lathe beds re ground by a firm in Huddersfield. After reading your request I emailed him for the address and phone number of the firm. I will get back to you as soon as I get a reply from him.Ted