Member postings for john fletcher 1

If you look on More latest post you will see some one has a similar problem to what you have and there is the answer. I think Boxford fitted a Santon, not sure of the part number.john

On the Dewhurst switch there are contacts at the lower part which are not used normally, you maybe able to swop your burnt contacts for them, I have done it for my friends in the past. When taking switches to pieces, do it a large clear plastic bag, that way you don't lose that important clip, spring or contact. As others have said, you should use a proper motor starter for the On/Off, and use the Dewhirst for direction only. The starter from Toolstation look to be a good buy with free delivery. John

I made one from bits and pieces at the Model Engineering class about 25 years ago. I later sold it when space in the workshop became a problem. Regarding the reamer, why not take the bits to your local machine shop, they will do it for you, or if there is a Model Engineering club close by get in contact with them, as I'm sure a member will have a 3/4" reamer or know some one who has. As Clive has already said, make a jig for the number punches, nothing looks worse than screw wiff numbers, spoils a good job. john

Bill, The instructions which Clive has given you are correct. You have to take the cover off the inverter front and see the rows of small terminals,( usually several  all marked up as Clive has said, they tiny and not easily read Fs, Fc and Fr. If there isn't wires in those position, then put three wires into those terminals Write down which colours you use.The other ends of those same coloured wire connect the speed control potentiometer get the colour RIGHT. Next locate in the inverter terminals Sc, S1 and S2 and as before connect the remaining three wires into those same three terminals. Finally connect the same three wires into the correct terminals in the forward and reverse switch. Look out for a PM. John

Before doing any thing more get your 3 phase motor sorted out. Having proper starter won't make any difference to your motor running and resilient mounting will make your motor run slightly quieter. First, have you got access to an insulation tester and multimeter ? if not, seek an electrician who has, then carry out insulation test on all three winding to earth, which is the motor frame, then between each winding. To do this your need to disconnect the Star point, it will have three connections on one terminal post. Whilst the Star point is available, check the resistance of each of the three windings, using a multi meter, set on the lowest ohms range,all should be almost the same resistance. Don't use the Insulation tester on the insulation resistance range, as that should be 500 Volts DC and will confuse the issue. If all those test are OK you don't need a motor, Check your wiring. It doesn't really matter from whom you buy your inverter they are much the same, programming is easier on some that is about all. There is a man, on, dare I say here, Home Workshop who often has ones for sale and also look on the net. I've fitted a few of this make "Huanyang " for my Model Engineering friends, bought via ebay and they are all OK, one was £90. 40. Should you decide to buy one.I have made a simplifier program which you could have a copy of. I hope that is of some help.John

That switch as shown on your circuit diagram is for single phase only. Also the picture of your motor terminal box shows it is wired in Star, I can see 3 wires on the N terminal, that is OK for 415 volts.You say you have a 3 phase supply, so why not obtain a proper motor starter fitted with No-Volt release and run it that way. .You would need a triple pole change over switch to get reverse. But if you do, ensure that you inter lock the starter and 3 pole switch so that you don't inadvertently try to go instantly from forward to reverse.Alternatively, as others have suggested connect the motor in Delta and get an inverter, which in my opinion is the way to go. I/we fitted a Huanyang inverter to my friend lathe and he is over the moon. John

I hadn't saw request until today, anyway you have sorted it yourself, I bet you feel 10 feet tall now. If you need forward and reverse you need to exchange the positions of R & S, leaving U1 & U2 where they are. Pleased to see that important Green and Yellow cable John

Regarding moving lathes and other machines, a friend uses a firm known as Pallet Ways. A Colchester Bantam was moved for about £85 including VAT. The article has to be on a pallet, the driver was very helpful and the lorry has a tail lift. I think value for money. I'm not sure where Pallet Ways are, maybe Middleborough. John

Hello Phil, there was a lot of split phase around Cloughton and Ravenscar. and on the farms up in the Whitby direction The Duchy of Lancaster saw mill was split phase. You could see the small unusual pole mounted transformer, with 11KV input, that was in the days of YEB and NEEB of course. OK about Andrew's, motor bike shop, we have bought several Honda 90 from them when Nick was the owner. Changed hands about 5 years ago when you bought your lathe from, can't remember his name, Dave Whittaker! . The lathe saga has been very interesting. Its good when people help each other out and share experiences.John

Hello Phil and many others. This has been a very interesting read regarding both lathe and the motor. You are correct Phil re the 440/480 volt motors, there were quite a few in the Scarborough area. I think the pole mounted transformer were know as the Scott connected type. 11KV input and 440/480 two or single phase or call what you will out. If you have access to JOHNSON & PHILLIPS transformer book there is an explanation on the transformer side of things.John

I recently fitted a Huanyang inverter to my friends, I think Harrison 170 lathe. I changed the two pole motor connections from STAR to DELTA, that took ten minutes or less. I fitted a 4 uF capacitor to the coolant pump and reconnected it into delta as well, so it now runs independently from 240 volts 13 amp socket outlet. I wired the lathe so that all the original control are still used, For/rev etc.The inverter bought from E...y for less than £100. Like other readers, I suggest you change the motor and fit an inverter. If you do buy a Huanyang 2.2KW inverter I have made a simplified programing sheet which I could let you have a copy, forget the book. John my friend is a very happy man, programing was easy and I'm no computer expert nor is my friend John. John

Hello Andy I think you should take the motor to a rewind shop and ask for their opinion and help. The motor is not a run of the mill motor. I think it will have a total of 6 connection which must be configured in the correct manner to ensure NO burner out. If you connect in Delta the 415 volt windings will, via an inverter receive 240 volts. Apparently there are modified inverters which do give out 415 volts. There was a discussion on Home workshop some time ago about modifying inverters apparently its a simple connection. Never need to try it out and haven't got a spare inverter to play with. Anyway,how is your Naerok ? John

From my experience, I think you need more capacitance, just how much I don't exactly know. I have done the same prior to inverters, fortunately I had a lot of high voltage capacitors to play around with. When the voltages were much closer than yours and when the motor sounded right, every thing was OK. I connected an ammeter and a voltmeter into the circuit and initially found one phase was drawing a lot more current and the motor obviously getting hot until I got the capacitance values right. Connect capacitors in parallel to increase capacitance and in series to reduce the value. Ex fluorescent light fitting capacitors are suitable source of capacitors. John

If you have over bent a piece of copper tube using a spring, useually if you wind up the spring in the correct direction the spring will come out, but it does take a lot of effort. In former times the heating and ventilation people who used 3 or maybe 5 inch steel heating pipe would fill the pipe with very dry sand with a cap either end and using Oxy/acetylene bottles to heat the pipe would make expansion loops on long runs. Now days they will have a hydraulic bender with a digital readout and key board. I think kiln dry sand as used by block pavers would be OK but make sure it is definitely dry. When I have used sand I always put it in the oven before use to drive out any moisture, ensuring I didn't generate steam and maybe blow the sealing caps off, ruining the job. Primitive but it works.John

Many thanks to Ken, Ian, Andy and any others who may have contacted me. It was item 31, once adjusted it works like a dream. I was given the inverter 10/15 years ago, its was part of a printing machine being scrapped and at the time I was very happy to be able to run a 3 phase motor with some speed control. I didn't dare to fiddle with the program, obviously not much better now. Great to know that helpful people are still around.John

I am not familiar with your make of switch, but if you form a truth table of open and closed pairs of terminal then you are part the way there. zero and one, open/closed . Mark each terminal some way or other dobs of paint or coloured nail varnish. With an ohmmeter or a buzzer continuity tester you can sort it out. The switch is 4 positons type so you are looking for vertical OFF, left forward and to the right reverse, I know its easier with a bit of experience. There looks to be sufficient number of terminals and once you have it sorted then follow the Dewhirst/Myford wiring arrangement. One thing I would like to point out ,that the switch on its own doesn't give any No-Volt release which is a good safety feature, a proper motor starter fitted with RED and GREEN pushes do.John

To all readers, my inverter is up and running as has been for several years. At the moment I have variable speed from around 950 rpm to about 2500. I would like to have around zero rpm upwards. Reader Quill ,has already come to my rescue and suggested looking at setting 42 which I have done and no change. I have been through the setting and written them up but cannot publish them here. If any one would like to check them out for me, please send me your details via a PM with your email address and then I'll forward you a copy.John

I have a Yaskawa VS J7 mini series inverter it is in working order. I would like to communicate with other Yaskawa users as I have a problem with altering the program. Please send me a PM and I will reply with our phone number and email address.John

If you Google Ravenscar you will find out more regarding the use of urine and the Alum mine works at Ravenscar. Part of the works is still visible and the National Trust have installed informative plaques around the site. Nicolas Crane and Coast programme did a documentary about making Alum at the site. Plenty of free car parking near by and a wonderful view of Robin Hood Bay also the afternoon tea at the Hotel have to be experienced to be appreciated. Just a satisfied customer.John

I had a bench top Alpine and the front pulley was on a taper, I used a bit of heat to release it. Following an article in ME several years ago, I took the machine to pieces as the there was a lot of slop in the spindle /rack. I made two eccentric bushes and Loctite them in place, transformed a cheap modest machine. I also have one of their band saw for cutting steel, must be more than 30 years old, it just keeps rolling along. John